Kinetics of cellular and humoral response of rabbits immunized with Mycoplasma pneumoniae

The cellular and humoral responses of rabbits immunized with Mycoplasma pneumoniae antigen in saline or incorporated in Freund's complete adjuvant were examined. Peripheral blood leucocytes were used for the leukocyte migration inhibition (LMI) test. Both groups of animals showed significant LMI activity in the presence of M. pneumoniae as well as crossreacting M. salivarium antigens but response to M. pneumoniae antigen was more pronounced. In the humoral response no such cross-reactivity was observed. Although some of the animals (3/8) demonstrated antibodies to M. salivarium prior to immunization the titers were not influenced by the immunization with M. pneumoniae antigen. Both groups of animals produced antibodies to M. pneumoniae antigen only, but significantly higher titers were observed in the adjuvant group. Cold hemagglutinins in both groups appeared earlier than the specific antibodies to mycoplasma. The adjuvant had no effect on the production of the cold agglutinins.