Experimental murine candidiasis: cell-mediated immunity after cutaneous challenge

Area of Science:

• Immunology
• Mycology
• Biochemistry

Background:

• Candida albicans is a common fungal pathogen.
• Detecting hypersensitivity is crucial for understanding candidiasis.
• Identifying specific antigens is key for diagnostic development.

Purpose of the Study:

• To isolate and characterize Candida albicans antigens for detecting hypersensitivity in a murine model.
• To compare the efficacy of different C. albicans preparations in eliciting immune responses.

Main Methods:

• Comparison of commercial extracts, cell wall, cytoplasmic, membrane, and glycoprotein fractions from C. albicans.
• Assay using footpad reactivity in cutaneously infected mice.
• Biochemical analysis including periodate oxidation and enzymatic digestion.
• Cell-mediated transfer of hypersensitivity.

Main Results:

• A cell wall glycoprotein (GP) fraction and a membrane extract (ppt-HEX) were most effective in demonstrating delayed hypersensitivity.
• GP fraction activity was reduced by oxidation and abrogated by proteolysis.
• ppt-HEX, a protein-carbohydrate extract, elicited footpad reactivity transferable by cells, not serum.

Conclusions:

• Membrane and GP fractions of C. albicans appear to elicit true delayed hypersensitivity reactions in mice.
• These fractions show promise as diagnostic tools for candidiasis.
• Further investigation into the specificity and biochemistry of these antigens is recommended.