Delayed hypersensitivity to syngeneic testicular cells induced by intratesticular bacterial infection in guinea-pigs.

Guinea-pigs were inoculated into the testis with viable Listeria monocytogenes, Escherichia coli, Pseudomonas aeruginosa or Staphylococcus aureus and elicitation of skin reactions was carried out with 5 x 10(6) syngeneic testicular cells 1 week later. Delayed-in-onset erythematous skin reactions against testicular cells were detected only when guinea-pigs were inoculated into the testis with L. monocytogenes. However, erythematous skin reactions were not detected when guinea-pigs were inoculated with E. coli, P. aeruginosa or S. aureus. Histological examination showed many infiltrating basophils in the erythematous skin reaction sites, and erythema was not accompanied by induration. Accordingly, the type of delayed skin reaction elicited with testicular cells 1 week after the inoculation of L. monocytogenes was considered as Jones-Mote type. These reactions were specific for testicular cells since the erythema or infiltrating basophils could not be detected after elicitation with sheep blood cells. Histological examination showed many infiltrating basophils at the skin reaction sites when guinea-pigs were inoculated with E. coli or P. aeruginosa. Dissociation between erythematous skin reactions and basophil infiltration was observed. Erythematous skin reactions were not detected when guinea-pigs with L. monocytogenes intravenously or subcutaneously.