Coccidioides immitis vaccine: potential of an alkali-soluble, water-soluble cell wall antigen.

C-ASWS-M, the alkali-soluble, water-soluble cell wall antigen of Coccidioides immitis mycelia, was evaluated for its vaccine potential in mice. Vaccination with 0.5-, 1.5-, or 3-mg doses of C-ASWS-M in complete Freund adjuvant provided a significant level of protection against intraperitoneal challenge with 1,500 arthroconidia (P < 0.0001 with each dose). Vaccination with 1 mg of C-ASWS-M protected mice against intranasal challenge with 50 (P < 0.05) and 500 (P < 0.01) arthroconidia, but not against intranasal challenge with 1,500 arthroconidia (P > 0.05).