C57BL/6J mice rendered hypersensitive to Blastomyces dermatitidis were protected from the lethal effects of a blastomyces infection. This protection was observed following a lethal intraperitoneal challenge with viable cells 15 days after subcutaneous inoculation with 3.9 X 104 viable cells. Delayed hypersensitivity was induced in C57 mice by two injections of Merthiolate-killed cells in adjuvant or by a single injection of viable cells. Development of hypersensitivity was determined at appropriate intervals by footpad injection with killed yeast cells.

This study further characterized the delayed hypersensitivity state induced in animals by Blastomyces dermatitidis exposure. Passive transfer of delayed hypersensitivity by transfer of cells and inhibition of migration of peritoneal exudate cells were studied, using sensitized mice of two inbred strains. Donor