Combinatorial actions of IL-22 and IL-17 drive optimal immunity to oral candidiasis through SPRRs

PLoS Pathog. 2024 Jul 1;20(7):e1012302. doi: 10.1371/journal.ppat.1012302. eCollection 2024 Jul.

Abstract

Oropharyngeal candidiasis (OPC) is the most common human fungal infection, arising typically from T cell immune impairments. IL-17 and IL-22 contribute individually to OPC responses, but here we demonstrate that the combined actions of both cytokines are essential for resistance to OPC. Mice lacking IL-17RA and IL-22RA1 exhibited high fungal loads in esophagus- and intestinal tract, severe weight loss, and symptoms of colitis. Ultimately, mice succumbed to infection. Dual loss of IL-17RA and IL-22RA impaired expression of small proline rich proteins (SPRRs), a class of antimicrobial effectors not previously linked to fungal immunity. Sprr2a1 exhibited direct candidacidal activity in vitro, and Sprr1-3a-/- mice were susceptible to OPC. Thus, cooperative actions of Type 17 cytokines mediate oral mucosal anti-Candida defenses and reveal a role for SPRRs.

MeSH terms

  • Animals
  • Candida albicans / immunology
  • Candidiasis, Oral* / immunology
  • Candidiasis, Oral* / microbiology
  • Interleukin-17* / immunology
  • Interleukin-17* / metabolism
  • Interleukin-22*
  • Interleukins* / immunology
  • Interleukins* / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout*
  • Receptors, Interleukin / immunology
  • Receptors, Interleukin / metabolism
  • Receptors, Interleukin-17 / immunology
  • Receptors, Interleukin-17 / metabolism

Substances

  • Interleukin-17
  • Interleukin-22
  • interleukin-22 receptor
  • Interleukins
  • Receptors, Interleukin
  • Receptors, Interleukin-17
  • interleukin-22, mouse
  • Il17a protein, mouse

Grants and funding

Research including salary support was provided by National Institutes of Health grants to SLG (R37-DE022550) and TCT (T32-AI089443). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.