Effect of slime extract from Pseudomonas aeruginosa on cell mediated immunity induced in mice by Salmonella typhimurium.

Immunity of mice intraperitoneally treated with slime extract and 24 h later intravenously immunized with live Salmonella typhimurium cells, was studied. The induced immunity was evaluated by determining the number of bacteria in the spleens and mortality of the animals. Slime extract in the dose of 200 micrograms/mice was found to suppress the immunity which manifested itself by enhanced proliferation of bacterial in the spleens and increased mortality as compared to control animals. The experiments on passive transfer of immunity against Salmonella typhimurium infection by splenocytes of slime extract-treated animals and then immunized, with those bacteria, revealed suppressive effect of the extract on transfer of the immunity. Similar results were obtained when splenocytes of mice sensitized with Salmonella typhimurium were given to animals pretreated with slime extract. The results obtained suggest the possibility of transfer of suppressive activity of splenocytes from slime extract-treated mice, to normal animals.