Some biological and immunological properties of extracellular slime from Pseudomonas aeruginosa.

Extracellular slime from 8 different Pseudomonas aeruginosa strains was extracted and purified. All slime-preparations exhibited immunogenic properties in rabbits vaccinated with detoxified or not detoxified slime. The antisera of both groups of immunized animals possessed strong hemagglutination activity against homologous slime. Immune hemagglutinins were present in the IgM and IgG fractions of serum globulins. The high value of these antibodies was found in rabbit's sera short after injection of slime-extract. The hemagglutinins quickly reached the peak value and maintained in serum over 60-70 days. Biological properties of lyophilized slime-preparations were defined in rabbit-skin test, local Shwartzman test, pyrogenic reaction and measured as LD50 for mouse. Intravenous injection of slime elicited marked changes in the number of leukocytes in the peripheral blood of rabbit. The animals responded to slime either with leukopenia passing into leukocytosis or with leukocytosis without leukopenia.