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Registration to attend in person is now closed. The event can be followed online by Zoom (see link below).
University of São Paulo-Faculty of Medicine Theater
Address: Avenida Doutor Arnaldo, 455, Cerqueira César, 01246-904, São Paulo, SP
Venue information and location: https://www.fm.usp.br/en/contact/location
To join the meeting and attend online on the 16th and 17th September, please follow the Zoom Webinar link below:
https://Universityofexeter.zoom.us/j/99443904404?pwd=dReshUYjNtPpqnYgSod2UWIPe3HD52.1
Please note that all times within the agenda below are displayed in local time in Sao Paulo. You can check your local time here.
For booking local hotels to the venue, we have set up a dedicated website with Mello Faro, however, you may wish to book via other websites directly as they may provide cheaper rates.
Website for bookings: https://mellofaro.com.br/_eventos/cmm-latam-unit-launch/
The following hotels are recommended for in-person attendees:
International airport: São Paulo/Guarulhos International Airport – Website: https://www.gru.com.br/en
Local airport: São Paulo/Congonhas Airport – Website: https://www.aeroportocongonhas.net/
Local bus station: Tiete Bus Terminal Sao Paulo, Terminal Rodoviário do Tietê – Vila Guilherme, São Paulo – SP, 01142-300, Brazil
For those arriving in to GRU Airport, GRARUCOOP is the official taxi provider for this airport and have a large fleet of taxis.
Prices are set according to each destination in São Paulo: just go to their both on arrival to pay (credit card accepted)
The GRARUCOOP taxi station is located on the side walk.
For those arriving into Congonhas Airport the recommended taxi company is RADIO TAXI VERMELHO E BRANCO for this company you will need to call in advance. The details are below:
Mello Faro is able to provide private services on demand. They are able to provide individual or small group services in executive vehicles, cars/vans, including English or Portuguese speaking drivers. They have representatives waiting at the arrival gate or please get in touch in advance using the below contact details:
Whatsapp (+55) 11 94718.4852
Email: marcelle@mellofaro.com.br
We will provide a shuttle service from the International airport to hotels on the Sunday 15th September but places will be very limited.
Timetable for Airport transport can be seen in the following table:
Date | Pick up Time | Pick up location | Drop off location | Van Number |
15th September | 07:00/07:15 | GRU terminal 3 | Radisson Oscar Freire Hotel | #1 |
15th September | 13:00/13:15 | GRU terminal 3 | Radisson Oscar Freire Hotel | #2 |
15th September | 19:30/19:45 | GRU terminal 3 | Radisson Oscar Freire Hotel | #3 |
16th September | 07:00/07:15 | GRU terminal 3 | FMUSP (Avenida Doutor Arnaldo, 455) | #4 |
Below is the timetable for services between the local hotels to the venue and return on 16-17 Sept. Please note that the spaces are very limited and we have tried to accommodate all those that are registered to stay at the hotel, so please only join this service if you are staying at the hotel.
Date | Time | Pick up location | Drop off location | Bus Number |
16th September | 08:45 | Radisson Oscar Freire | FMUSP (Avenida Doutor Arnaldo, 455) | #1 |
16th September | 08:45 | Radisson Oscar Freire and Mercure Pinheiros | FMUSP (Avenida Doutor Arnaldo, 455) | #2 |
16th September | 08:45 | Ibis Budget Paulista | FMUSP (Avenida Doutor Arnaldo, 455) | #3 |
Date | Time | Pick up location | Drop off location | Bus Number |
16th September | 20:15 | FMUSP (Avenida Doutor Arnaldo, 455) | Radisson Oscar Freire | #1 |
16th September | 20:15 | FMUSP (Avenida Doutor Arnaldo, 455) | Radisson Oscar Freire and Mercure Pinheiros | #2 |
16th September | 20:15 | FMUSP (Avenida Doutor Arnaldo, 455) | Ibis Budget Paulista | #3 |
Date | Time | Pick up location | Drop off location | Bus Number |
17th September | 08:15 | Radisson Oscar Freire | FMUSP (Avenida Doutor Arnaldo, 455) | #1 |
17th September | 08:15 | Radisson Oscar Freire and Mercure Pinheiros | FMUSP (Avenida Doutor Arnaldo, 455) | #2 |
17th September | 08:15 | Ibis Budget Paulista | FMUSP (Avenida Doutor Arnaldo, 455) | #3 |
Date | Time | Pick up location | Drop off location | Bus Number |
17th September | 20:15 | FMUSP (Avenida Doutor Arnaldo, 455) | Radisson Oscar Freire | #1 |
17th September | 20:15 | FMUSP (Avenida Doutor Arnaldo, 455) | Radisson Oscar Freire and Mercure Pinheiros | #2 |
17th September | 20:15 | FMUSP (Avenida Doutor Arnaldo, 455) | Ibis Budget Paulista | #3 |
1. What are the event dates and location?
The event will take place on Monday, September 16, and Tuesday, September 17, 2024, at the Lecture Theatre, Faculdade de Medicina, Universidade de São Paulo, Avenida Doutor Arnaldo, 455, Cerqueira César, São Paulo, Brazil (01246-904).
2. Can I attend online?
Yes! To join the event online please ensure that you have registered to attend online. you will be sent full joining details. The Zoom Webinar link below is in the webpage and listed below.
https://Universityofexeter.zoom.us/j/99443904404?pwd=dReshUYjNtPpqnYgSod2UWIPe3HD52.1.
3. Where should I go when I arrive at the venue?
Please proceed to the main entrance. A team member will greet you, provide your name badge, and a QR code for entry to the university for both days. Be sure to keep the badge and QR code secure.
4. What language will the event be in?
The event will be held in English. If you’re attending online, you can enable automatically generated captions in other languages via Zoom.
5. Who are the keynote speakers or panelists?
For a full list of speakers, please refer to the agenda available on this webpage.
6. Who can I contact for more information?
If you have any questions or need support, please contact the FAILSAFE team at FAILSAFE@exeter.ac.uk.
7. Will I need to arrange my own transport to the venue?
Yes, we recommend arranging transportation in advance. A bus timetable and travel information are available on this webpage, but spaces on the provided buses are limited and reserved for those staying at the designated hotels. Information on local taxi services are on this page.
8. Will refreshments be provided?
Yes, refreshments, lunch, and dinner will be provided for in-person attendees. If you have specific dietary needs, please inform us in advance, or bring any necessary items if the catering may not meet your requirements.
9. How can I stay updated on event changes?
Check this webpage for the latest updates. Any announcements or changes will be posted here.
10. Do I need any special software to attend online?
Yes, the event will be broadcast via Zoom. We recommend downloading the Zoom software before the event. You can download it here: Zoom Download.
11. I am a poster presenter; where should I set up my poster?
You can set up your poster upon arrival in the designated poster area. Check your allocated board number in the agenda. Posters will be displayed throughout the event and can be taken down after the last session on Day 2.
16th September PROGRAMME: Centre of Medical Mycology Latin America (CMM LATAM) Unit Launch event
8:45 | Shuttle buses leaving from hotels to venue |
9:00 – 10:30 | Registration and Arrival Coffee/tea |
10:30 – 12:00 | Welcome and introduction to the CMM LATAM Unit
Chaired by Prof. Gordon Brown [MRC Centre of Medical Mycology Director & FAILSAFE Project lead, University of Exeter, UK] · Prof. Arnaldo Lopes Colombo: Fungal infection burden and challenges faced in LATAM [CMM LATAM Local Director, Federal University of São Paulo (UNIFESP), Brazil] · Prof. Elaine Bignell: CMM LATAM Unit as a global hub for tackling fungal disease [CMM LATAM Exeter Director & FAILSAFE Project lead at the University of Exeter, UK] · Prof. Carlos Gilberto Carlotti Junior: CMM LATAM Unit and Medical Mycology at USP [President of the University of São Paulo, Brazil] · Prof. Richard Follet: Working in partnership to tackle global challenges [Vice President for Global Engagement at the University of Exeter, UK] · Sarah Clegg: Strengthening ties: the role of the UK-Brazil partnership for a healthier world [UK’s Minister Counsellor and Deputy Consul General in Sao Paulo] · Dr. J. Claire Hoving: Fungal infection burden and challenges faced in Africa [Associate Professor, AFRICA CMM Unit, University of Cape Town, South Africa] · Prof. Thuy Le: Fungal infection burden and challenges faced in Asia [Co-Director, Tropical Medicine Research Center for Talaromycosis, Pham Ngoc Thach University of Medicine, Vietnam] |
12:00 – 13:30 | Lunch break |
13:30 – 15:10 | Fungal infections in Latin America: Challenges & synergies
Chaired by Prof. Sandro Almeida [Faculdade de Ciências Farmacêuticas, University of São Paulo (USP), Brazil] · Prof. Helena Nader: Addressing Infectious Diseases Through a One Health Approach: Perspectives from the Brazilian Academy of Sciences [President Brazilian Academy of Sciences, UNIFESP, Brazil] · Dr. Marcio Rodrigues: Fostering innovation in public health: the Inova Program of Fiocruz [Inova Program Fundação Oswaldo Cruz (Fiocruz), Brazil] · Prof. Pilar Ramon-Pardo (online): Supply chain for antifungal diagnostics and treatments in LATAM [Pan American Health Organization (PAHO)] · Oddi Aasheim: Building on GAFFI’s LatAm Experience: Why an NGO is Essential in Combating Fungal Disease Worldwide [Board Chair, Global Action for Fungal Infections (GAFFI)] · Dr. Tom Chiller: Fungal Infections in the Americas: Working together in Public Health [Chief of the Mycotic Diseases Branch, Centers for Disease Control and Prevention (CDC), USA] |
15:10 – 16:00 | Coffee/tea break with pastries and fruit |
16:00 – 18:00 | Workshop & Panel discussion: Tackling Endemic LATAM Mycoses
Chaired by Prof. Carlos Pelleschi Taborda [Institute of Biomedical Sciences (ICB), USP, Brazil] · Prof. Beatriz Gomez Giraldo: Histoplasmosis in LATAM [School of Medicine and Health Sciences, Del Rosario University, Colombia] · Prof. Arnaldo Colombo: Systematic Review of Candidemia & drug resistance in Brazil [CMM LATAM Local Director, Federal University of São Paulo (UNIFESP), Brazil] · Prof. Josh Nosanchuk: Cryptococcal melanin- from virulence factor to drug target [Professor and Senior Associate Dean, Albert Einstein College of Medicine, USA] · Dr. Dallas Smith: Implantation mycoses in LATAM [Epidemiologist, Centers for Disease Control and Prevention (CDC), USA] · Dr. Ricardo de Souza Cavalcante: The burden of Paracoccidioides and Coccidioides in LATAM [Assistant Professor, Department of Infectious Diseases, Dermatology, Diagnostic Imaging and Radiotherapy, Botucatu School of Medicine – UNESP, Brazil] |
18:00 – 18:30 | ‘A musical tribute to the CMM LATAM’ by Rosana Puccia (lyricist & singer), David Pasqua (piano), Marcelo Rocha (bass), Edson Ghilardi (drums) |
18:30 – 20.00 | Poster session and Networking (buffet dinner) |
20:15 | Shuttle buses leaving to hotels |
17th September PROGRAMME: FAILSAFE inaugural network scientific meeting
8:15 | Shuttle bus leaving from hotels to venue |
8:30 – 9:15 | Arrival Coffee/Tea |
9:15 – 10:00 | Welcome – FAILSAFE project and network
Chaired by Prof. Neil Gow [MRC Centre of Medical Mycology, University of Exeter, UK & President ECMM] · Dr. Shahida Syed: The Global AMR Innovation Fund (GAMRIF) [Project lead, The Global AMR Innovation Fund (GAMRIF), UK] · Prof. Dame Sally Davies (online): Antimicrobial drug resistance [UK Special Envoy for AMR, UK Government] · Prof. Charlotte Watts: TBC [FCDO Chief Scientific Advisor, UK Foreign Commonwealth and Development Office (FCDO), UK] · Profs. Gordon Brown and Elaine Bignell: Strategic vision, needs and objectives of FAILSAFE [FAILSAFE Project leads at the University of Exeter, UK] |
10:00 –10:30 | Coffee break with pastries |
10:30 – 12:10 | Antifungal drug resistance: The scale of the problem
Chaired by Dr. Tom Chiller [Chief of the Mycotic Diseases Branch, Centers for Disease Control and Prevention (CDC), USA] · Dr. Andre Luiz de Abreu (online): Antifungal drug resistance and the NAP on AMR [Technical Team for Antifungal Resistance, Ministry of Health in Brazil] · Dr. Alexandra Meagan Cameron (online): Fungal Priority Pathogens List and follow on activities [Head of the Department – AMR Division, World Health Organisation (WHO)] · Prof. Dr. rer. nat. Wieland Meyer: Azole drug resistance in A. fumigatus – The environmental situation in Latin America [Westerdijk Fungal Biodiversity Institute of the KNAW, Netherlands] · Dr. Anuradha Chowdary: Drug resistant dermatophytoses [Director, Department for Medical Mycology, Vallabhbhai Patel Chest Institute, India] · Prof. Tom Harrison: The Potential of Combination Treatments to Mitigate Antifungal Resistance [Professor of Infectious Diseases and Medicine, St George’s University of London, UK] |
12:10 – 13:10 | Lunch & networking |
13:10 – 14:30 | Tackling antifungal drug resistance
Chaired by Prof. Beatriz Lucia Gomez Giraldo [Professor, School of Medicine and Health Sciences, Universidad del Rosario, Colombia] · Prof. Arturo Casadevall (online): One Health and climate change, the future of fungal diseases [Professor and Chair, Molecular Microbiology & Immunology, Johns Hopkins Bloomberg School of Public Health, USA] · Dr. Manu De Rycker: Drug Discovery in Academic-industry partnership [Head of Translational Parasitology and Portfolio Leader for Kinetoplastid Drug Discovery at the Drug Discovery Unit (DDU), University of Dundee, UK] · Prof. Ashraf Ibrahim: Antifungal vaccine development from bench to bedside [David Geffen School of Medicine, UCLA, USA] · Dr. Leila Lopes Bezerra: Sweet Medicine Chemistry and innovative solutions for immunodiagnosis of emergent mycosis [CEO & Founder of BIDiagnostics, Brazil] |
14:30 – 15:00 | Coffee/tea break with pastries and fruit |
15:00 – 16:20 | Industry, R&D and Capacity Development
Chaired by Prof. Adilia Warris [MRC Centre of Medical Mycology, University of Exeter, UK] · Prof. Chris Thornton: Development and marketing of novel diagnostics and gaps to close [Director, ISCA Diagnostics Limited, K] · Dr. Obidiah Plante: mRNA technology for anti-infective vaccine development [Senior Director, Infectious Disease Research, Moderna, USA] · Dr. Mark Jones: Lead development (manogepix series) into clinical trials and beyond [Head of Development, Basilea Pharmaceutica International Ltd] · Prof. William Horsnell: Building capacity through mycology training programmes and Q&A session [MRC Centre of Medical Mycology, University of Exeter, UK]
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16:20 – 18:00 | Funding Opportunities
Chaired by Prof. Fausto Almeida [Ribeirao Preto Medical School, University of São Paulo, Brazil] · Dr. Ioanna Kostaki: Funding opportunities [Medical Research Council, UKRI] · Holly Wright: FAILSAFE Application process, remit, upcoming calls and Q&A [FAILSAFE Project Manager, University of Exeter, UK]
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Speed networking | |
18:00 – 20.00 | Poster session and Networking (buffet dinner) |
20.00 | End of meeting |
20:15 | Shuttle buses leaving to hotels |
Please direct any questions to failsafe@exeter.ac.uk
We are looking forward to welcoming those that are presenting posters and invite all attendees to please visit the poster station during the event.
Ref
|
Presenter | Title and Abstract |
P1 | Prof. Alexandre Bailão
[Universidade Federal de Goiás] |
Histoplasma capsulatum ACE1 plays a role in fungal virulence and adaptation to high copper levels. Histoplasma capsulatum is a fungal microorganism that causes histoplasmosis. During infection by Histoplasma, the immune cells use many defense mechanisms to hamper infection progress. For instance, phagocytes change the availability of metallic micronutrients, such as iron, zinc and copper, as a fungistatic strategy. On the other hand, microorganisms reprogram gene expression to control the capture or detoxification of a specific micronutrient to subvert the hostile space inside the phagocytic cells. Generally, the expression of genes that participate in copper homeostasis is controlled by the transcription factors Ace1 and Mac1. Ace1 governs the fungal adaptation to copper excess, while Mac1 promotes the adaptation to metal scarcity. This work aims to analyze the roles of Ace1 in maintaining copper homeostasis in Histoplasma. ACE1 gene expression was induced in conditions of copper excess. Data obtained with reporter strains have shown that ACE1 induction occurs in a dose-dependent fashion. MAC1 gene expression was upregulated in a copper-deprived environment. During macrophage infection using cell lines and BMDM cells, a time-dependent change in the expression levels of these regulators was observed. ACE1 was induced in the first 24 hours and MAC1 was positively regulated 48 hours post-infection, suggesting a temporal change in copper availability in the time course of macrophage infection. ACE1-knockdown strains were sensitive to high copper and slightly sensitive to copper deprivation, as well as showed hampered virulence in macrophages. As expected, Ace1 activates fungal detoxification machinery, Crp1 and Crd2. Intriguingly Ace1 represses Mac1 and copper transporters Ctr1 and Ctr2. These results demonstrate that H. capsulatum undergoes a transient copper excess in phagosomes and relies on a copper detoxification pathway regulated by Ace1 to fight host-imposed copper poisoning. |
P2 | Prof. Ana Marisa Fusco Almeida
[São Paulo State University] |
Efficacy of Nitrofuran and Indole derivatives against Histoplasma capsulatum biofilm and pharmacological safety in three-dimensional cultures and in vivo.
Histoplasmosis is a systemic mycosis caused by the dimorphic fungus Histoplasma capsulatum of cosmopolitan distribution. In 2022, the World Health Organization (WHO) classified this fungus as a high priority. Histoplasmosis therapy is long and complex, as the antifungal agents used cause many toxic effects, relapses, and refractory cases. Nitrofuran and indole derivatives have already demonstrated efficacy against fungi. Additionally, there is evidence that the fungus H. capsulatum can form biofilms, which are sessile communities that allow microorganisms to survive in hostile environments. This study aimed to assess the efficacy of nitrofuran derivatives against biofilms formed by H. capsulatum. Additionally, the toxicity of these derivatives was evaluated in alternative models such as Caenorhabditis elegans, Galleria mellonella, and Zebrafish, as well as in three-dimensional (3D) cultures. The metabolic activity of biofilms was evaluated using the tetrazole salt reduction (XTT) method after treatment. The study utilized scanning electron microscopy (SEM) and confocal microscopy to visualize damage to mature biofilms. The cytotoxicity index (CC50) was calculated using GraphPad Prism 5.0 software, and the animal survival curve was plotted. The compounds were highly effective against both early-stage and mature biofilms at concentrations equal to or twice those required to kill planktonic fungal cells (7,81 at 31,25μg/mL). The micrographs show a reduction in biofilm metabolic activity, thickness, and extracellular matrix. The compounds exhibited low toxicity in 3D cultures, with a CC50 of 13.22 μg/mL at concentrations of ≥ 250 μg/mL. Furthermore, low toxicity or no toxicity was observed in alternative models of C. elegans, G. mellonella, and zebrafish, even at high concentrations. These results are important in the quest for new potent alternatives, especially against fungal biofilms. |
P3 | Dr. Beatriz Andrade
[Hospital Pequeno Príncipe]
|
Use of Antifungals Provided by the Endemic Mycoses Program in a Tertiary Paediatric Hospital: Analysis of Cost Avoidance. Introduction: Invasive fungal infections (IFIs) are a critical concern in paediatrics, associated with high mortality rates. The most common pathogens include Candida spp. and Aspergillus spp. Within the Unified Health System (UHS) context, access to systemic antifungals is limited due to their high cost, exacerbated by increasing demand. The Ministry of Health (MS), through SCTIE/MS ordinances Nº 55 and 59/2022 and Information Note Nº 09/2023, provides antifungals for confirmed infections, enhancing access to timely treatments. Given the economic impact of systemic antifungals on the UHS, evidenced by their classification in category A of the hospital’s ABC analysis, requests to the MH represent a strategy for cost avoidance and improved treatment access. Objectives: To describe the profile of antifungals provided by the MH and the cost avoidance from these requests from the hospital’s perspective. |
P4 | Carolina Melchior do Prado
[Federal University of Paraná]
|
Sporotrichosis treatment failure in cats with initial antifungal susceptible Sporothrix brasiliensis. Cat-transmitted sporotrichosis is an emerging zoonosis, mainly caused by the thermo-dimorphic fungus Sporothrix brasiliensis. In the last 30 years, this disease has become a major public health concern in Brazil and other Latin American countries. While in vitro antifungal resistance is increasingly reported, the impact on treatment outcome is unknown. A total of 108 S. brasiliensis feline isolates from the Triple Border region between Brazil, Paraguay, and Argentina were collected upon treatment initiation and cats were subsequently treated with itraconazole and potassium iodide. Each cat was evaluated and classified according to the clinical form of their lesions in three groups: 1) cutaneous disseminated; 2) fixed cutaneous and 3) extracutaneous. To determine the clinical outcome, they were monitored for the whole treatment duration. Genetic relatedness of isolates was assessed using short tandem repeat (STR) genotyping. In vitro antifungal susceptibility of nine antifungal compounds was evaluated using Clinical and Laboratory Standards Institute (CLSI) reference standards M38 and M27 for the mycelial and yeast phases, respectively. Microscopy was used to confirm a homogenous yeast or mycelial phase prior to inoculation. Among the 108 S. brasiliensis isolates, 100 were from Foz do Iguaçu, 4 were from Ciudad del Este, Paraguay and 4 were from Hernandarias, Paraguay. Clinical forms and outcomes of cats are displayed in Table 1. From our preliminary data, the mortality rate of cats with disseminated sporotrichosis was 61% (Table 1). Interestingly, there was no mortality of cats with the fixed cutaneous or extracutaneous form, while both groups received the same treatment. Additionally, treatment duration, ranging between 2 and 15 months, did not correlate with a clinical form. By applying STR genotyping, all S. brasiliensis isolates displayed several highly related genotypes, indicating widespread clonal transmission. Subsequent, antifungal susceptibility testing showed higher minimum inhibitory concentrations (MICs) against most antifungals for the mycelial phase, when compared to the yeast phase. Based on tentative epidemiological cutoff values (ECVs), 12 and 9 isolates were classified as non-wild-type for amphotericin B and terbinafine, respectively. For the other tested antifungal, all the isolates were classified as wild-type when ECVs were available. Clinical breakpoints that require information about MIC distribution, PK/PD studies, and outcome data are also not available for cat-transmitted sporotrichosis. In conclusion, the varying clinical presentations with differences in mortality is not caused by initial in vitro resistance or a more virulent genetic background. We also did not find an explanation for the prolonged treatment duration of cats with fixed cutaneous form and no apparent comorbidities. Possibly, erratic itraconazole pharmacokinetics/pharmacodynamic (PK/PD) is involved, however this was not investigated as this is currently not available for cats. |
P5 | Prof. Cesar Mota
[Federal University of Minas Gerais (UFMG)] |
Surveillance of resistant Candida in community wastewater in Brazil’s third largest city. Antifungal resistance (AFR) is an increasing global health threat that necessitates coordinated action to prevent its spread across the One Health sectors (environment, humans, animals). Environmental surveillance of AFR is currently lagging in One Health programs, but the recent establishment of infrastructure for monitoring SARS-CoV-2 in wastewater offers an opportunity for similar AFR monitoring efforts. However, AFR surveillance via wastewater is still in its infancy, and adequate methodologies have yet to be tested, standardized, and made accessible to LMICs, which could help optimise global AFR policies, particularly in LMICs. In this study, we will present data from the surveillance of Candida auris and other resistant Candida species in Belo Horizonte (Brazil’s third-largest capital), over a period of six months. |
P6 | Dr. Chibuike Ibe
[University of the Free State] |
The epidemiology and drug resistance among Candida pathogens in Africa: Candida auris now may be leading the pack Background: Invasive candidiasis (IC) has become more prevalent in the last 2 decades now killing about a million persons annually. Despite the threat, our antifungal arsenal has not changed in more than 3 decades. In Africa, the overuse of the available antifungal has led to widespread resistance to fluconazole and increasing breakthrough infections with echinocandin-resistant Candida auris. Method: We conducted a systematic search of databases to include reports on the epidemiology and drug resistance of Candida pathogens in Africa. The search only included reports in English that have sequenced resistance genes associated with resistance to cell membrane and cell all active drugs. Results: Data from 17 reports with resistance genes sequenced in 7 African countries show 2 812 strains of identified Candida species from patient samples, including blood and 64 unspeciated Candida strains. Data also show 24 Candida strains – C. auris (11), C. parapsilosis (9), C. glabrata (2), C. dublinenesis and C. orthopsilosis) – isolated from high-touch areas and hands of staff. Candida isolates obtained from patients include 1 436 susceptible and 1 376 resistant strains. Among the resistant strains, 1 339 were resistant to majorly azoles while only 37 were echinocandin-resistant. C. auris was the most common (743 drug resistant strains of 1 036 isolates), followed by C. parapsilosis (464 resistant strains of 622 isolates) while C. dublinenesis was the least common species (a resistant strain of 6 isolates). Forty-five C. auris strains were multidrug- and 5, pandrug-resistant. C. auris Clade III is predominant in Africa while clade 1 is more drug resistant. In Nigeria, C. auris clade I and IV strains were isolated and, clade I strains harboured Erg11:Y132F substitution with 100% mortality. Similarly, in South Africa clade I isolates are more resistant to fluconazole and echinocandin than clades III and IV and, high fluconazole-resistant isolates from clades I, III and IV harboured a high number of clade-specific substitutions (i.e., Erg11:Y132F, VF125AL and K177A/R/N335S/E343D). In echinocandin-resistant clades I and III isolates, Fks1:S639P and D642Y substitutions were predominant. Conclusion: From our results, there is paucity of data to understand the epidemiology of IC in Africa and put the disease in proper perspective. More research is needed to improve the diagnosis of IC and understand the mechanisms of evasion of antifungal therapies by Candida pathogens. Echinocandins remain the most potent antifungal for treating IC. Adopting a One Health approach and implementing the Nairobi declaration will improve the disease management and patient outcome in Africa. |
P7 | Dr. Claudia Banda Flores
[Instituto de Medicina Tropical Alexander von Humboldt (IMTAvH)] |
The INKA program (Improving National Knowledge and Awareness of fungal infections in Peru).
Background: In Peru, there is a significant gap in the training and education related to diagnosing and treating fungal diseases, particularly outside the capital, Lima. Online courses offer a practical solution to bridge this gap. This study evaluates the outcomes of online courses focused on fungal diseases in HIV patients, specifically Cryptococcosis and Histoplasmosis, targeting a diverse group of health professionals across Peru’s 24 regions. The courses were developed by the Improving National Knowledge and Awareness of Fungal Infections in Peru (INKA) program, funded by the Centers for Disease Control and Prevention (CDC).
|
P8 | Dr. Cristina de Castro Spadari
[University of São Paulo (USP)] |
Effect of miltefosine unloaded or loaded in alginate nanoparticles on interaction with Cryptococcus neoformans in the blood-brain barrier and macrophages
Cryptococcosis is an opportunistic disease that causes meningitis, with ~223,100 cases/year. The therapeutic arsenal for fungal diseases is limited and is even more difficult in cryptococcal meningitis due to the difficulty in crossing the blood-brain barrier (BBB). In addition, Cryptococcus yeasts are considered ideal intracellular parasites, surviving in macrophages and using them as a “Trojan horse” to penetrate the BBB. Previous studies indicate that a potential alternative is the use of alginate nanoparticles as a carrier for miltefosine (MFS), since they reduce toxicity and promote sustained release of the drug, increase animal survival, and decrease fungal burden in tissues using the model of fungal infections in vertebrates and invertebrates. Thus, this study aimed to understand the interaction of alginate nanoparticles and MFS with the BBB and macrophages. Our results confirm that the use of nanoparticles reduces the toxicity of MFS in both BBB and macrophage models tested. Furthermore, free MFS (2 μg/mL) and carried-in nanoparticles (100 μg/mL) are efficient in reducing the passage of yeasts through the BBB. Likewise, treatments with free MFS (2, 12 or 24 μg/mL) and nanoparticles (25 or 50 μg/mL) help in the macrophage-yeast interaction, increasing the association index and decreasing fungal viability when compared to the untreated control. The data obtained demonstrate that the use of alginate nanoparticles as a carrier for MFS and free MFS showed potential as an alternative for the treatment of cryptococcal meningitis, showing activity in important processes of the infection.
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P9
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Dr. Ganeshkumar Arumugam
[University of São Paulo, UNESP-ICT, Sao Jose Dos Campos]
|
Sclareolide exhibits antifungal activity against Cryptococcus neoformans through increase in production of reactive oxygen species
Cryptococcus species are recognized as significant opportunistic fungal pathogens. They are the causative agents of cryptococcal meningitis, a condition associated with high mortality due to limited treatment options and the virulence of pathogens. Current treatment regimens typically involve fluconazole, amphotericin B, and flucytosine. However, the incidence of life-threatening invasive fungal infections has risen dramatically, underscoring the need for improved or novel therapeutic approaches for managing cryptococcal infections.
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P10 | Dr. Guillermo Garcia-Effron
[Universidad Nacional del Litoral (CONICET)] |
Enhancing Access to Fungal Disease Diagnostics in Argentina: The Impact of a Centralized Fungal Disease Response Center and Referral Network. Access to fungal disease diagnosis is essential to reduce mortality rates. In Argentina, access varies widely, particularly outside the Buenos Aires metropolitan area. Most healthcare facilities in these regions are small, with under 150 beds, making it challenging to maintain specialized mycology labs. To address this, a centralized Fungal Disease Response Center (FDRC) and a referral network were established to serve the Santa Fe and Paraná metropolitan areas, covering about 1 million inhabitants. A survey of 18 microbiology labs in the Santa Fe region identified significant gaps in diagnostic capabilities. Starting in October 2022, the FDRC offered a range of mycology tests, including those from the WHO’s essential in-vitro diagnostics list, such as microscopy, culture, molecular diagnostics, and detection of fungal biomarkers. A referral network, including a courier service, was established, supported by a website and mobile app for service requests and result reporting. Training and technical assistance were also provided. In 2023, the FDRC’s first full year, we received samples from 878 patients across 22 institutions, performing 1,151 tests on 891 samples. The most common tests included Aspergillus galactomannan quantification and molecular diagnostics. The FDRC diagnosed 101 fungal infections (62 proven and 39 probable) including fungemias (n=38), histoplasmosis (22), aspergillosis (13), deep-seated candidiasis (11), Pneumocystis pneumonia (5), and others (12), and detected antifungal resistance. Average diagnosis turnaround times were 6.2 hours for antigen-based and 21.5 hours for molecular-based biomarkers from sample dispatch. Another point to consider is that our FDRC covers all institutions in the region. This comprehensive coverage has enabled us to initiate population-based studies, as we have the necessary population denominators and can ensure we receive nearly all samples from patients with suspected mycoses of a known region. This is crucial because such data with reliable denominators are scarce. Currently, we are conducting population-based studies on candidemia, Pneumocystis pneumonia, histoplasmosis in transplant patients, tuberculosis-histoplasmosis coinfections in HIV patients, and more. Initial data on histoplasmosis prevalence show that the incidence of this mycoses is higher than suspected, even exceeding known hyperendemic areas as Ohio and Mississippi, reaching 4% in kidney-transplant recipients (4 cases in the first 100 analyzed patients) and 6% in people living with HIV (3 histoplasmosis cases and 4 genXcan positive results per 50 sputum samples from patients suspected of having tuberculosis. One was a coinfection). The FDRC’s first-year results demonstrated that regionally centralized services can provide high-quality diagnostics, overcoming the limitations of smaller, less-equipped labs and the challenges of using distant referral laboratories. This initiative significantly improved the timely diagnosis of fungal infections, which is crucial for patient outcomes. Moreover, it´s provide comprehensive data on mycoses prevalence based on reliable denominators. |
P11 | Dr. Jéssica Chechi
[Institute of Biomedical Sciences, University of São Paulo] |
Investigation of the Zinc-Responsive HcZrt2 Gene in the Survival Mechanisms of Histoplasma capsulatum. Histoplasmosis is one of the most important systemic and endemic mycoses in the Americas and the world. The infection is acquired by inhalation of Histoplasma capsulatum propagules, such as microconidia and small mycelial fragments, mostly found in soil contaminated with droppings of certain bird species or bat guano. After inhalation, these propagules convert into yeasts in the lung. The disease may also develop through the reactivation of a quiescent focus of a past infection. Histoplasma spp. is an intracellular pathogen and yeasts are highly adapted to the host, using macrophages as a proliferative niche while avoiding the microbicidal mechanisms inside these cells. As a result, innate immune cells are unable to control H. capsulatum on their own. Within the intracellular compartment, yeast replication requires the acquisition of several essential nutrients, including metal ions. Studies show that, although iron and zinc are sufficiently abundant in resting macrophages, once these phagocytic cells are activated by pro-inflammatory cytokines causes restriction of these metals to yeast within macrophages as a form of nutritional immunity. Thus, the objective of this study is to elucidate and characterize genes involved in the acquisition of zinc metal for a better understanding of the mechanisms of virulence, survival, and intracellular replication of the fungal pathogen H. capsulatum. Expression analyzes of genes related to the acquisition of zinc (ZAP1, ZRC1, ZRC2, ZRT1 and ZRT2 genes) were performed. After analyzing the genes, previously reported in the databases of sequences and genomes of H. capsulatum and other related fungi, the gene ZRT2, associated with the acquisition of zinc was selected to obtain mutants of H. capsulatum using the CRISPR-Cas9 methodology. The design of guide RNAs for the ZRT2 gene was performed using CRISPOR software and inserted into the plasmid. E. coli were used for plasmid expansion and concentration. Then, Agrobacterium tumefaciens (LBA 1100 and AGL-1 strains) were electroporated to receive the plasmids and co-cultivation with H. capsulatum was performed. Under dilution conditions of 1:1 and 1:3 (bacteria: fungus) and a time of 48 hours, we achieved successful transformation. However, mixed transformed and non-transformed yeasts were present even in the selection medium. We are currently working with cocultivation of A. tumefaciens and H. capsulatum strains in higher hygromycin B concentrations to better select the transformed yeasts. Microscopic and bioinformatics analysis showed that mutant cells had distinct morphologies compared to wild-type yeasts, such as smaller and standard size, as well as absence of pseudohyphae. |
P12 | Jessica Paulette Segovia Mota
[Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE)] |
Analysis of the current distribution of Coccidioides spp. in soil samples from Valle de las Palmas, Baja California. Coccidioidomycosis, known as valley fever, is a re-emerging infectious disease in the American continent, caused by two species of ascomycetous fungi of the genus Coccidioides. The causal agent of this disease has been identified in arid and semiarid regions, mainly in California, in the southwestern United States, Central America and South America, as well as in various parts of northern Mexico, including Sonora, Coahuila, Nuevo León and Baja California. Despite the high incidence rates of this disease, few positive isolates have been obtained from environmental samples. This may be due to the non-uniform distribution of Coccidioides spp. in soils, the presence of inhibitors, the low amount of environmental DNA and the fact that current methods require sequencing techniques and long time. For this reason, the use of the Droplet Digital PCR (ddPCR) technique was proposed as a detection method from a small soil sample. 20 soil samples were taken from active burrows in Valle de las Palmas, where the presence of Coccidioides spp had previously been demonstrated, and 55 from Rancho Carrizo, Golondrinas and San José de la Zorra; DNA was extracted, and a nested PCR was performed to check the presence of Coccidioides. Physicochemical parameters such as organic matter, humidity, granulometry, electrical conductivity and pH were determined to evaluate if there is a correlation between these variables and the presence or absence of the fungus. Finally, biogeographic maps were developed with points from previous sampling and those obtained recently, in order to generally know the current distribution of the fungus in areas close to a positive area. 5 positive samples were obtained by Nested PCR. ddPCR detected a greater number of positive samples, suggesting that this technique is much more sensitive and effective than nested PCR. |
P13 | Dr. Jonatas Erick Maimoni Campanella
[Universidade Federal de São Carlos] |
Exploring the function and the biochemistry of the Δ9-desaturase SdeA in Aspergillus fumigatus. Aspergillus fumigatus is a human pathogenic mold that causes life-threatening deep mycoses in immunocompromised patients, such as Invasive Pulmonary Aspergillosis, leading to elevated healthcare costs and high morbimortality rates. Thermotolerance is a key virulence determinant for A. fumigatus. However, the effects of heat shock (HS) on the fungal cell membrane are poorly understood despite the importance of this organelle in sensing and adapting to temperature fluctuations. HS triggers an adaptive response involving the heat shock transcription factor (HsfA) and molecular chaperones. Simultaneously, membrane adaptation to keep fluidity occurs via the alteration of lipid composition dictated by the balance between saturated and unsaturated fatty acids. In A. fumigatus, HS reduces the levels of unsaturated phospholipids, impacting membrane composition and stress responses. The Δ9-fatty acid desaturase SdeA is an essential enzyme partially regulated by HsfA, which plays a crucial role in unsaturated fatty acid synthesis and links the HS response to membrane lipid composition. A. fumigatus SdeA is an Hsp90 client protein and localizes to the endoplasmic reticulum. Depletion of sdeA reduced the expression of Psi-producing oxygenase genes involved in oxylipin synthesis and increased mycelial sensitivity to caspofungin. We report that SdeA tridimensional structure harbors two domains essential for catalysis: an N-terminal conserved fatty acid desaturase domain (FADS) and a C-terminal Cytb5 domain, the latter virtually absent in mammalian Stearoyl CoA Desaturases, such as SDC1. We demonstrated that the Cytb5 domain is essential for viability and cannot be functionally complemented by any other Cytb5-like proteins in the fungal cell. Additionally, we found that these two domains are separated by a rigid alfa-helix hinge, which is also crucial for the structural architecture of the enzyme. The presence of the hinge between the protein domains prevents direct interaction between the FADS and Cytb5 domains within the same protomer, leading to the hypothesis that SdeA functions as a dimer, where the FADS domain of one protomer interacts with the Cytb5 domain of the other to provide reducing power for the desaturation reaction. To validate this hypothesis, we conducted a co-immunoprecipitation (co-IP) experiment, confirming that SdeA exists as a dimer in vivo. We also demonstrate that the hinge is a critical link between the protomers, stabilizing the predicted dimeric structure. We argue that the unique structural features and functional roles of the Δ9-fatty acid desaturase SdeA in A. fumigatus underscore its potential as a promising target for antifungal drug development. The organization of SdeA in a Cytb5 domain fusion protein may represent a sophisticated adaptation mechanism, enabling the fungus to thrive under diverse environmental conditions, including HS. |
P14 | Julia Figueiredo
[University of São Paulo]
|
PRMs and its O-linked fractions of Sporothrix spp. markedly induce chemokine release by immune cells
Fungi are known to have a cell wall composed of a high carbohydrate content (>80%) and, among them, there are common structural polysaccharides (chitin and β-glucans), mainly distributed in the inner cell wall layer. The outer cell wall layers vary depending on the fungus species and, can be considered as a carbohydrate fingerprint for host recognition. The cell walls of Sporothrix schenckii and Sporothrix brasiliensis posses a peptidorhamnomannan (PRM) in their outer layer with N- and O-glycosidically linked chains. Previous studies had demonstrated that the N-linked and O-linked rhamnose epitopes of PRM are important for patient’s antibody recognition. Further studies also demonstrated that PRM from S. brasiliensis has some unknown structures and it induces a strong inflammatory response. In this work we have studied the role of PRMs purified from the two main zoonotic species, S. schenckii (PRM Ss21) and S. brasiliensis (PRM Ss23), in the human monocyte response and host recognition. We also isolated an enriched PRM O-linked fractions, denominated here as O-linked Ss21 and O-linked Ss23, to challenge human PBMCs. Blood samples from seven donors were used for PBMCs isolation through Ficoll method. Then, cells were resuspended in RPMI 1640 supplemented with 10% NHS, counted, 2.106 cells were distributed in 48-well plates, and incubated at 37ºC and 5% CO2. Following, the PBMCs were stimulated with PRM Ss21, PRM Ss23, O-linked Ss21 and O-linked Ss23 at 40 µg/well. The positive control was stimulated with 1 µg/mL of LPS and the negative control was incubated only with RPMI with 10% NHS. The supernatants were collected after 1 day and 5 days and evaluated through ELISA assay for cytokines and chemokines (TNF-α, IL-6, IL-1β, IL-10, IL-8, CXCL1 and CCL5). Supernatants recovered after 1-day stimulation were pooled for proteome profiler assay. RESULTS: After 1 day, PBMCs stimulated with O-linked fractions showed a stronger chemokine secretion, with no significant cytokine release. On the other hand, PRM Ss21 stimulated Th1/Th2/Th17 cytokines while PRM Ss23 stimulated Th1/Th17 cytokines, the latter being interestingly able to stimulate the inflammasome pathway as indicated by IL-1β secretion (Figure 1). After 5-days stimulation, the O-linked fractions were able to induce a Th1 response, with chemokine profile being maintained; cytokine profiles were Th1/Th2/Th17 for either PRM Ss21 or PRM Ss23, (Figure 2). The cytokine array proteome profiler demonstrated higher signals for chemokines (CXCL10, CXCL1, CCL5, MIP-1α/MIP-1β, CCL2 and IL-8) related to all PRM fractions studied (Figure 3). PRMs and its enriched O-linked fractions are associated mainly with cell recruitment through chemokines, indicating an essential role of phagocytes, such as neutrophils and macrophages, in the response against sporotrichosis. The inflammasome activation with no IL-10 response in cells stimulated with PRM Ss23 may relate to a disorganized granuloma usually seen in specimens of animals infected with S. brasiliensis. S. schenckii infection is always related to a well controlled granuloma formation and a benign disease. Since the enriched O-linked PRMs showed a decreased cytokine profiles when compared to PRMs, we hypothesize that important immunogenic residues associated with N-linked chains can paly a key role in the cytokine response. Together, our data suggests that Sporothrix spp PRMs and their correspondent O-linked fractions are associated with immune cells activation, but for each species playing distinct roles that may have impact in the disease outcome. S. brasiliensis is know to be a highly pathogenic species, causing a severe disease mainly in domestic animals. We highlight a strong CXCL10 signal in response to PRM Ss23. CXCL10 is associated with the CXCR3 receptor, which is related to skin diseases.
|
P15 | Prof. Karen Ferreira
[Universidade Federal de São Paulo – UNIFESP] |
EVs from different yeast strains of Sporothrix brasiliensis seem to exhibit varying levels of dependency on dectin-1 and dectin-2 in the response of BMDCs, macrophages, and neutrophils to the vesicles. Introduction: Sporotrichosis is a subcutaneous mycosis that affects the skin and lymphatic system of humans and animals. The disease is caused by at least four pathogenic species, including Sporothrix brasiliensis. The immune response against these species is not yet fully understood, but EVs could carry important components that could help clarify the infection mechanism. Results: EVs from the 5110 strain could enhance fungal survival and the production of TNF-α, but this effect was lost in dectin-1 and dectin-2 knockout cells. To test this assumption, we used a binding assay with dectin-1 and dectin-2 chimeras (an “antibody-like” protein composed of the binding portion of the receptor fused to a human Fc body). Next, we investigated whether these results were limited to DCs. Interestingly, compared to DCs, macrophages were less permissive to yeast, and EV treatment did not affect yeast survival. EVs alone could also stimulate macrophages, but unlike DCs, dectin-1 and dectin-2 were not essential for the response. The same experiments were performed for the M1168 strain, and we observed a higher dependency on dectin-1 and dectin-2 than in the 5110 strain. When we analyzed the 1168 strain with a Hog1 knockdown, we found that regardless of the phagocytes, CFU levels were higher, and the strain showed increased resistance to neutrophils. On the other hand, EVs from primed DCs were able to decrease the fungal load of this strain and induced more CD4+ T cells. Conclusion: In summary, EVs from the 5110 strain show a higher dependency on dectin-1 and dectin-2 in the response of DCs to the vesicles. However, the M1168Δhog1 strain might display higher virulence. The resistance to neutrophils is particularly interesting in sporotrichosis, and DCs are essential for controlling the infection by S. brasiliensis. |
P16 | Dr. Neil McCarthy
[Queen Mary University of London (QMUL)]
|
Tissue invasion dynamics of human gut-resident C. albicans strains in Crohn’s disease. Introduction: The human intestine is routinely colonised by fungal species including Candida albicans, which has been strongly implicated in the pathogenesis of inflammatory bowel disease. In healthy hosts, C. albicans adopts a commensal yeast lifestyle, but change in local conditions can trigger the formation of tissue-invasive filaments that secrete Candidalysin (CLYS) toxin and disrupt the gut barrier. Dynamics of this morphological switch are influenced by genotypic and phenotypic variation among C. albicans strains, but also by epithelial contact and the physical forces encountered, yet it remains unclear how these factors impact host response and mucosal inflammation. Methods & Results: Clinical isolates of C. albicans were obtained by primary culture of mucosal biopsy tissue from healthy controls (HC) and patients with Crohn’s disease (CD). Phenotypic, genomic, and proteomic analyses revealed that CD-derived isolates more readily formed filaments and expressed key adhesion-associated genes including IHD1. When exposed to CD-derived C. albicans strains, blood neutrophils from healthy donors displayed increased swarming and NETosis, whereas monocyte-derived macrophages released greater amounts of pro-inflammatory cytokine IL-1β. To investigate host-microbial interactions in a more physiologically relevant setting, a human ‘gut-on-a-chip’ system was developed to assess tissue invasion potential in vitro. These assays confirmed that CD-derived strains display increased epithelial adhesion and translocation under conditions that mimic flow and stretch forces within the human intestine. Conclusion: Gut-adapted C. albicans strains from HC and CD donors exhibit distinct biological profiles that impact on host immune responses and shape interactions with the gut barrier in a novel organ chip model. |
P17 | Patrícia Lima
[ICT-UNESP] |
Optimizing Photodynamic Therapy Against Candida albicans Using Functionalized Porphyrins with Peripheral Pt(II) Complexes. Current treatments for candidiasis are increasingly limited by the rise of antifungal resistance, highlighting the need for alternative approaches such as antimicrobial photodynamic therapy (aPDT). This study aimed to assess the efficacy of platinum(II) tetra-cationic porphyrins (3Pt and 4Pt) as photosensitizers in aPDT against Candida albicans. For this, we conducted several evaluations, including: 1) the impact of porphyrin-mediated aPDT on planktonic cultures, filamentation, and biofilms of C. albicans; 2) the toxicity of 3Pt and 4Pt to human keratinocytes; 3) the production of reactive oxygen species (ROS) in fungal cells; 4) the effects of aPDT on patient-derived microcosm biofilms with denture stomatitis; and 5) the in vivo effect of aPDT on burn infection in Galleria mellonella. Statistical analysis (p < 0.05) revealed that both porphyrins had a Minimum Inhibitory Concentration (MIC) of 16 µM, with 3-Pt demonstrating superior performance in killing curve assays and biofilm reduction. Notably, 3-Pt achieved complete inhibition of planktonic cultures within 40 seconds of irradiation and resulted in a 4 Log10 (CFU) reduction in biofilms. Both porphyrins effectively inhibited filamentation and exhibited no toxicity to keratinocytes. Furthermore, 3-Pt facilitated ROS production and significantly reduced yeast, streptococci, and staphylococci in microcosm biofilms. In the In vivo study, 3-Pt aPDT improved the survival of G. mellonella larvae and prevented systemic infections. These findings suggest that 3-Pt porphyrin holds considerable promise as a photosensitizer for aPDT in treating Candida infections. |
P18 | Samanta de Matos Silva
[Sao Paulo State University (UNESP)] |
Deciphering the Mechanisms Underlying Host-Pathogen Interaction in Biofilms Formed by Histoplasma capsulatum within a 3D Small Airway Epithelial Tissue Model. Dimorphic fungi, exemplified by genera Histoplasma, exhibit a unique ability to undergo morphological changes, a mycelial form in soil and a yeast form in the host. This facultative intracellular pathogen is known to initiate respiratory infections in mammals, which can progress to systemic infections. Moreover, their capacity to form biofilms is of particular concern due to the inherent difficulty in controlling biofilm-related infections. While research efforts have predominantly focused on host-pathogen interactions using two-dimensional (2D) cell models, the literature extensively covers a spectrum of three-dimensional (3D) models elucidating host-pathogen interactions in various microorganisms, including bacteria, viruses, and scarce fungi, including Candida albicans and Aspergillus spp. However, research on dimorphic fungi remains limited in this context. Among the molecular biology techniques employed to overcome existing barriers, CRISPR/Cas9 technology stands out as a gene-editing tool capable of conducting gene screening to unveil the signaling pathways involved in host-pathogen interactions during infection. In this context, our research aimed to elucidate the mechanism of host-pathogen interaction of H. capsulatum biofilms within a 3D small airway epithelium tissue model using CRISPR knockout (CRISPRko). To achieve this, we developed a 3D small airway epithelium tissue model through the co-cultivation of differentiated lung epithelial cells (Calu-3), lung fibroblast cells (MRC-5), and macrophage-like cells (THP-1) at an Air-Liquid Interface (ALI) in a proportion of 3:3:1 and collagen type I hydrogels as the scaffold material. The model’s viability was assessed using the XTT assay and quantification of total carbohydrates over 28 to 30 days post-ALI differentiation. The standardization of the 3D small airway epithelium tissue was visualized using Fluorescence Microscopy (FM), Transmission Electron Microscopy (TEM), Multiphoton Multiparametric Microscopy (MMM), and the infection using FM and MMM. Among bovine, rat tail, and human collagen type I sources, both rat tail and human collagen type I demonstrated the capability to form hydrogels after 40 min. of polymerization. Subsequent validation of our model, assessed through cell viability using the XTT method and total carbohydrate quantification, revealed an intriguing pattern. We observed an increase in metabolic activity and higher sugar consumption between the 7th and 14th days, as well as between the 9th and 19th days of model development. Significantly, this phenomenon coincided with the period of ALI differentiation of lung epithelial cells. Examining infection results through FM and MMM images unveiled notable filamentation of H. capsulatum in planktonic and biofilm-derived cells. FM and MMM showed a transition from the yeast phase to the fungus’s mycelial phase. Remarkably, the biofilm-derived infection visually demonstrated more extensive filamentation than the planktonic yeast infection. Our results suggest that these factors, coupled with the physical barrier presented by the 3D model, could contribute to hyphae formation. In summary, our research showcases so far the potential of a 3D small airway epithelium tissue model combined with CRISPRko screening to elucidate the intricate mechanisms underlying host-pathogen interactions in Histoplasma biofilms. |
P19 | Dr. Thaila Reis
[University of Sao Paulo – FCFRP] |
Aspergillus fumigatus conidial surface-associated proteome reveals factors for fungal evasion and host immunity modulation. The section Fumigati is composed by Aspergillus fungal strains presenting variable pathogenicity levels. Within this section, Aspergillus fumigatus, an opportunistic pathogen, is responsible for approximately 70% of cases of invasive pulmonary aspergillosis (IPA) presenting the highest pathogenicity rates. Some data have demonstrated that for A. fumigatus, the ability to grow at high temperatures and under nutrient-limiting conditions, in addition to the ability to produce secondary metabolites, favor its pathogenicity and help the survival inside the human host. API is established following inhalation of infectious fungal propagules produced asexually by Aspergillus and called conidia. These propagules are found dispersed in the environment and can eventually be inhaled by the human host, initiating infection. Thus, conidia are the first point of contact between the fungus and human cells (of the lung epithelium and the immune system) and, therefore, are extremely important for the progression (or not) of the disease. Despite the importance of conidia in the initial steps of API, there is scarce information about the surface proteins of A. fumigatus conidia involved in fungal evasion and host immunity modulation. Here, we analysed the conidial surface proteome of A. fumigatus, two closely related non-pathogenic species, Aspergillus fischeri and Aspergillus oerlinghausenensis, as well as pathogenic Aspergillus lentulus, to identify such proteins. After identifying 62 proteins exclusively detected on the A. fumigatus conidial surface, we assessed null mutants for 42 genes encoding these proteins. Deletion of 33 of these genes altered susceptibility to macrophage, epithelial cells, and cytokine production. Notably, a gene that encodes a putative glycosylasparaginase, modulating levels of the host pro-inflammatory cytokine IL-1?, is important for infection in an immunocompetent murine model of fungal disease. These results suggest that A. fumigatus conidial surface proteins are important for evasion and modulation of the immune response at the onset of fungal infection. |
P20 | Prof. Vanice Poester
[Universidade Federal do Rio Grande (FURG)] |
Antifungal susceptibility of Candida spp. from blood culture in Southern Brazil. Introduction: Candidemia is a continuous challenge for public health, having a significant impact on hospital costs and high morbi-mortality to patients, especially when involving Candida sp. multidrug-resistant strains. Thus, studies focusing in the antifungal susceptibility of Candida sp. are essential for aiding in the control and treatment of candidemia. We aimed to report the identification and susceptibility pattern of Candida species isolated from candidemia cases at a tertiary hospital in southern Brazil. Materials and Methods: A retrospective study was conducted including 38 Candida strains isolated through blood cultures collected from hospitalized patients with candidemia between January 2020 and December 2023 at the University Hospital of Rio Grande (HU-FURG/EBSERH). Isolates were identified by chromogenic agar, followed by confirmation through MALDI-TOF (Matrix-Assisted Laser Desorption/Ionization Time-of-Flight). Antifungal susceptibility to fluconazole and amphotericin B was evaluated by microdilution assay according to the Clinical and Laboratory Standards Institute (CLSI) protocol (M27-A2). Results: Around a half of the candidemia cases (52.7%; 20/38) were caused by C. albicans. Candida non-albicans corresponded to 47.3% (n=18), being the majority of them identified as C. parapsilosis (n=12), followed by C. tropicalis (n=2) and one case each of C. krusei, C. guillermondii, C. glabrata and C. haemulonii. Among the C. albicans strains, the resistance rate to fluconazole was 40% (n=8) and all isolates (n=20) were susceptible to amphotericin B. Fluconazole resistance was also observed in one isolate of C. parapsilosis (8%; 1/12) as well as in the C. krusei isolate. C. glabrata was dose-dependent susceptible, and other strains showed susceptibility to fluconazole. Resistance to amphotericin B was observed only in the isolate identified as C. haemulonii. Conclusion: C. albicans and C. parapsilosis were the most prevalent species causing candidemia in our hospital in Southern Rio Grande do Sul, as reported in other regions of Brazil. Although the rate of resistance to amphotericin B reported here is low, the high rate of fluconazole resistance showed, especially among our C. albicans isolates, brings an alert for physicians to be aware. Therefore, our study besides adding important data to the local surveillance of the emergence of Candida sp. resistant, instigates future studies focusing in molecular targets to elucidate the mechanisms involved in this resistance. |
P21 | Dr. Gabriel Davi, Marena
[ICB-University of Sao Paulo]
|
Analysis of virulence and pathogenicity of different clades of Candida auris in an in vivo model of Galleria mellonella. Introduction: Candida auris is an emerging yeasts that causes bloodstream infections, especially in immunocompromised patients, and presents high resistance and virulence rates. To date, five clades have been established worldwide and the number of outbreaks caused by this microorganism has been increasing every year, causing concern in the medical community. Therefore, this study investigated the heterogeneity among clades of C. auris by evaluating the virulence profile and mechanism of infection using an in vivo model of Galleria mellonella. Methods: G. mellonella was infected with different clades of C. auris, C. albicans ATCC 5341 and C. parapsilosis ATCC 22019 for virulence and histopathologic evaluation. Results: Aggregative strains of C. auris InP13 and VEN C6 had a greater rate of melanization and larval mortality among the C. auris isolates. C. albicans caused the most melanization among all strains at the highest inoculum concentration (106 cells/mL). Histopathologic examination showed a greater number of granulomas in the lower and upper extremities of G. mellonella. The granulomas ranged from 0.07 to 0.11 nm in diameter. All strains showed biofilms adhering to larval tissue, which was more evident for InP13, VEN C6 and C. albicans Infiltration of yeasts in tissues, pseudohyphae and chlamydospores, a resistance structure formed by C. albicans in stress environments, were observed. In conclusion, the aggregative strains were more virulent and had a greater ability to form biofilms and granulomas, showing heterogeneity among C. auris. |