Oral Presentation 14th Lorne Infection and Immunity 2024

Exploring the female genital tract mycobiome in young South African women using metaproteomics (#54)

Tamlyn K Gangiah 1 , Arghavan Alisoltani 1 , Matthys Potgieter 1 , Liam Bell 2 , Elizabeth Ross 2 , Arash Iranzadeh 1 , Zac McDonald 2 , Imane Allali 1 3 , Smritee Dabee 1 4 , Shaun Barnabas 1 , Jonathan M Blackburn 1 , David L Tabb 1 5 6 , Linda-Gail Bekker 1 7 , Heather B Jaspan 1 4 , Jo-Ann S Passmore 1 8 9 , Nicola Mulder 1 10 , Lindi Masson 1 8 11 12
  1. Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
  2. Centre for Proteomic and Genomic Research, Cape Town, South Africa
  3. Laboratory of Human Pathologies Biology, Department of Biology and Genomic Center of Human Pathologies, Mohammed V University, Rabat, Morocco
  4. Seattle Children's Research Institute, Seattle, USA
  5. Bioinformatics Unit, South African Tuberculosis Bioinformatics Initiative, Stellenbosch University, Stellenbosch, South Africa
  6. DST–NRF Centre of Excellence for Biomedical Tuberculosis Research, Stellenbosch University, Stellenbosch, South Africa
  7. Desmond Tutu HIV Centre, Cape Town, South Africa
  8. Centre for the AIDS Programme of Research in South Africa, Durban, South Africa
  9. National Health Laboratory Service, Cape Town, South Africa
  10. Centre for Infectious Diseases Research (CIDRI) in Africa Wellcome Trust Centre, University of Cape Town, Cape Town, South Africa
  11. Central Clinical School, Monash University, Melbourne, Australia
  12. Burnet Institute, Melbourne, VIC, Australia

Female genital tract (FGT) diseases such as bacterial vaginosis (BV) and sexually transmitted infections are prevalent in South Africa, with young women being at an increased risk. Since imbalances in the FGT microbiome are associated with FGT diseases, it is vital to investigate the factors that influence FGT health. The mycobiome plays an important role in regulating mucosal health, especially when the bacterial component is disturbed. However, we have a limited understanding of the FGT mycobiome since many studies have focused on bacterial communities and have neglected low abundance taxonomic groups, such as fungi. To reduce this knowledge deficit, we present the first large-scale metaproteomic study to define the taxonomic composition and potential functional processes of the FGT mycobiome in South African reproductive-age women. We examined FGT fungal communities present in 123 women by collecting lateral vaginal wall swabs for liquid chromatography-tandem mass spectrometry. From this, 39 different fungal genera were identified, with Candida dominating the mycobiome (53.2% relative abundance). We observed changes in differential abundance at the protein, genus, and functional (gene ontology biological processes) level between BV states. In women with BV, Malassezia and Conidiobolus proteins were more abundant, while Candida proteins were less abundant compared to BV negative women. Correspondingly, Nugent score was negatively associated with total fungal protein abundance. The clinical variables, Nugent score, pro-inflammatory cytokines, chemokines, vaginal pH, Chlamydia trachomatis, and the presence of clue cells were associated with fungal community composition. The results of this study reveal the diversity of FGT fungal communities, setting the groundwork for understanding the FGT mycobiome.