Chemiluminescence response of peritoneal exudate cells from mice infected with virulent and avirulent strains of Toxoplasma gondii.

The zymosan-triggered chemiluminescence response of peritoneal exudate cells from mice infected with relatively virulent or avirulent Toxoplasma gondii strains was examined at various intervals after infection. Toxoplasma infections increased the background chemiluminescence compared with controls, but higher values were attained earlier in virulent than avirulent infection. A phase of transient unresponsiveness to zymosan was observed with both types of toxoplasma strains. Chemiluminescence continued to decline even after the addition of zymosan on day 3 of infection with the virulent strain but only on day 10 with the avirulent strain. Generation of chemiluminescence was enhanced in mice which had been infected with either strain for 1 month.