Immunological Mechanisms in Vulvovaginal Candidiasis

Vulvovaginal candidiasis (VVC) arises when commensal Candida species, most often Candida albicans, breach the mucosal barrier and provoke a local immune reaction. The vaginal epithelium acts as a first line of defence, deploying antimicrobial peptides and maintaining tight junction integrity. Upon fungal contact, innate immune cells—including neutrophils, macrophages and dendritic cells—are recruited, sensing fungal cell wall ligands and releasing pro-inflammatory cytokines such as interleukin-1β. Activation of the NLRP3 inflammasome in resident leukocytes amplifies this response, yet excessive inflammasome activity can drive symptomatic inflammation without clearing the fungus. Adaptive immunity, notably Th17 cells secreting interleukin-17 and interleukin-22, contributes to mucosal resistance by enhancing epithelial barrier function and antimicrobial peptide production. A delicate balance between resistance (pathogen elimination) and tolerance (inflammation control) is essential; disruption of this equilibrium underpins recurrent or chronic disease. Genetic variants affecting cytokine pathways, coupled with shifts in the vaginal microbiome, further modulate host susceptibility and the clinical outcome of VVC.

Research from Nature Portfolio

Clinical analysis of symptomatic versus asymptomatic women has identified overexpression of NLRP3 and caspase-1 inflammasome components as a key discriminator of disease. In affected individuals, heightened inflammasome assembly correlates with increased neutrophil influx and elevated levels of interleukin-1β and interleukin-8 in vaginal fluid. Concurrent upregulation of fungal virulence determinants—such as secreted aspartyl proteases and hypha-associated proteins—suggests that inflammasome activation not only marks but also drives pathological inflammation. These findings position the inflammasome as both a mechanistic linchpin in symptom generation and a potential target for immunomodulatory therapy in VVC.

Immunological Mechanisms in Vulvovaginal Candidiasis publication trend

The graph below shows the total number of articles in immunological mechanisms in vulvovaginal candidiasis across all publications each year (not limited to Nature Index journals).

Technical terms

Inflammasome: A multiprotein complex in innate immune cells that, once assembled, activates inflammatory cytokines and initiates pathogen clearance or symptomatic inflammation.

Th17 cells: A subset of CD4+ T lymphocytes that produce interleukin-17 and interleukin-22, pivotal for mucosal defence and epithelial barrier reinforcement.

Cytokine: A small secreted protein released by immune cells that orchestrates communication, cell recruitment and activation during immune responses.

Neutrophil: A short-lived innate immune cell that rapidly migrates to infection sites to engulf pathogens and release antimicrobial mediators, sometimes contributing to tissue inflammation.

References

1. Vulvovaginal Candidiasis: A Current Understanding and Burning Questions. Journal of Fungi (2020).
2. Impact of interkingdom microbial interactions in the vaginal tract. PLOS Pathogens (2024).
3. NLRP3 inflammasome is a key player in human vulvovaginal disease caused by Candida albicans. Scientific Reports (2017).
4. Th17 Cells and IL-17 in Protective Immunity to Vaginal Candidiasis. PLOS ONE (2011).
5. IL-22 and IDO1 Affect Immunity and Tolerance to Murine and Human Vaginal Candidiasis. PLOS Pathogens (2013).
6. Vaginal Heparan Sulfate Linked to Neutrophil Dysfunction in the Acute Inflammatory Response Associated with Experimental Vulvovaginal Candidiasis. mBio (2017).
7. Immune Sensing of Candida albicans. Journal of Fungi (2021).
8. It Takes Two to Tango: How a Dysregulation of the Innate Immunity, Coupled With Candida Virulence, Triggers VVC Onset. Frontiers in Microbiology (2021).