FUNGISORT · Sorting out host recognition of fungal infection
FP7 — People (Marie Curie Actions)
- Duration
- 2014-06-01 → 2016-05-31
- EU contribution
- €183,470
- Participants
- 1
- Scheme
- MC-IIF
Lines connect the coordinator with its partners.
Results in brief
Sorting out host recognition of fungal infection
The fungus Candida albicans is a common cause of human infections with serious morbidity, but is also a commensal that is part of the normal intestinal microbiota. Innate immune cells must tolerate commensal colonization of C. albicans, yet deal effectively with opportunistic mucosal and systemic invasion. The interplay between the immune system and fungi occurs predominantly at the level of the fungal cell wall, where fungal pathogen-associated molecular patterns (PAMPs) are recognized by Pattern Recognition Receptors (PRRs) of innate immune cells. The cell wall composition of virulent C. albicans hyphae differs from C. albicans yeasts, resulting in differential immune recognition and signalling. The goal of the FungiSort project was to study PRR interactions with fungal PAMPs and to develop new tools that can be applied to determine commensal and pathogenic states of C. albicans. Sortagging is a site-specific protein-labeling technique that can be used for the flexible attachment of affinity handles like biotin or fluorophores. The sortagging technique can be used to label purified proteins or to perform immunoprecipitation experiments with proteins expressed on the surface of living cells. For the FungiSort project, the sortagging technique was introduced in the host laboratory and applied to the C-type lectin receptor DC-SIGN that plays an important role in innate immune recognition of C. albicans. The carbohydrate recognition domain (CRD) of DC-SIGN was expressed with a sortase tag and labeled with biotin of TAMRA and used in pull down and confocal microscopy experiments, respectively. A stable THP1 macrophage cell line expressing DC-SIGN with a sortase tag was used for live cell sortagging and phagocytosis experiments. We identified glycoproteins that are secreted by C. albicans and that interact with DC-SIGN. We are currently investigating if these secreted glycoproteins occur in vivo and whether they have DC-SIGN-mediated immunomodulatory functions. The results of the FungiSort project contribute to our understanding of innate immune recognition of fungal infections and provide new avenues for the development of new diagnostic tools to distinguish commensal and pathogenic fungi.
Data: CORDIS, © European Union
Project objective
The fungus Candida albicans is a common cause of human infection with serious morbidity, but the organism is also a commensal yeast that is part of the normal gut microbiota. It is becoming increasingly clear that the composition of the microbiome plays an important role in health and disease. For instance, recently it was shown that commensal fungi in the gut can contribute to the severity of colitis (inflammation of the gut). Immune recognition of C. albicans is mediated by Pattern Recognition Receptors (PRRs) of innate immune cells. The major PRRs involved in fungal immune responses are C-type lectin receptors Dectin-1, DC-SIGN, Dectin-2, Mincle, Galectin-3 and Mannose Receptor. Signaling by C-type lectin receptors depends on the formation of signaling protein complexes, but these complexes are poorly characterized. We need to understand C-type lectin-mediated immune responses to fungi to improve diagnostics and generate new anti-fungal drugs and vaccines. My approach to increase our understanding of fungal immune recognition is to (1) Characterize C-type lectin receptor complexes that drive innate recognition of C. albicans using sortase technology (2) Study immune recognition of commensal and pathogenic Candida strains and isolates with fluorescent PRR binding domains and (3) Investigate the contribution of fungi to the development and/or severity of human inflammatory bowel disease (IBD) by quantitative proteomics. Fungal infections are on the rise so we need to understand how the immune system detects pathogenic behavior of commensal fungi. My expertise in the fungal host-pathogen field and the advanced technologies that I have developed put me in a unique position to advance our understanding of immune-fungal interactions. The results of this IIF project will offer a clear perspective on future clinical applications.
Original text from CORDIS.
Participants
- UNIVERSITEIT UTRECHT · UtrechtCoordinatorNetherlands
Links
Data: CORDIS, © European Union