How major fungal infections can initiate severe autoimmune diseases

Area of Science:

• Immunology
• Microbiology
• Autoimmunity

Background:

• Autoimmune diseases are commonly linked to viral and bacterial infections.
• The role of fungal infections in autoimmune disease pathogenesis is largely unexplored.
• Antibiotic use disrupts microbial balance, potentially favoring fungal growth.

Purpose of the Study:

• To investigate the potential role of fungal infections in causing severe autoimmune diseases.
• To elucidate the immunological mechanisms linking fungal infections to autoimmunity.
• To propose a hypothesis for fungal-driven autoimmune disease development.

Main Methods:

• Review of existing literature on fungal infections and immune responses.
• Analysis of immunological pathways involving T regulatory cells, T helper 17 cells, and key cytokines.
• Hypothesis generation based on observed correlations between fungal prevalence and autoimmune disease incidence.

Main Results:

• Major fungal infections can decrease regulatory T (T_REG) cells.
• Fungal infections increase the production of interleukin-23 (IL-23), CD4 T_H17 T-cells, IL-17, and IL-22.
• Disruption of the microbiome by antibiotics favors fungal expansion.

Conclusions:

• Fungal infections represent a potential, underappreciated cause of severe autoimmune diseases.
• The shift in immune response, characterized by reduced T_REG cells and increased T_H17 cells and associated cytokines, is a key pathogenic pathway.
• Increased incidence of autoimmune diseases may be linked to susceptible individuals experiencing fungal overgrowth.