Candida parapsilosis complex induces local inflammatory cytokines in immunocompetent mice

Area of Science:

• Mycology
• Immunology
• Infectious Diseases

Background:

• The Candida parapsilosis complex, including C. parapsilosis sensu stricto, C. orthopsilosis, and C. metapsilosis, is increasingly prevalent in clinical settings.
• Disseminated infections by this fungal complex are associated with high mortality rates.
• Host-fungus interactions within the Candida parapsilosis complex remain poorly understood.

Purpose of the Study:

• To investigate host-fungus interactions in mice infected with the Candida parapsilosis complex.
• To analyze inflammatory cytokine profiles, histopathology, and fungal burden in key organs.
• To determine the role of different enzymatic profiles within the 'psilosis' group.

Main Methods:

• Infection of mice with six strains from the Candida parapsilosis 'psilosis' group.
• Analysis of inflammatory cytokine levels (IL-22, TNF-α) in spleen, kidney, and lung.
• Histopathological examination of infected organs and quantification of fungal burden.

Main Results:

• A robust interleukin 22 (IL-22) and tumor necrosis factor α (TNF-α) response was observed in all infected organs, irrespective of species or enzymatic profile.
• Elevated TNF-α and IL-22 levels correlated with spleen inflammation and fungal load.
• Fungal cells were primarily detected in the spleen and kidney by day 2 post-infection, with observed kidney damage including glomerular retraction and tubular destruction.

Conclusions:

• A strong inflammatory response, particularly involving IL-22 and TNF-α, is characteristic of Candida parapsilosis complex infections in mice.
• These cytokines may play a significant role in the host's defense mechanisms against fungal dissemination.
• The study highlights the importance of the innate immune response in controlling Candida parapsilosis complex infections.