Immune response to the oral administration of a new meningococcal preparation, serogroup A, under experiment

In the experiment on rabbits immune response to the oral administration of a new Neisseria meningitidis whole culture preparation, serogroup A, was demonstrated. The preparation was based on the acetone fixed culture, grown by the continuous flow method under a computer-controlled constant level of oxygen. The immunological activity of the preparation was demonstrated. In the blood sera of rabbits examined by immunoenzyme assay and the passive hemagglutination test, a multiple increase in the content of hemagglutinating and IgG antibodies to polysaccharide, outer membrane proteins and lipooligosaccharide was noted, their content remaining at a high level for 303 days (the term of observation). The oral immunization with the preparation protected mice infected with N. meningitidis live culture, serogroup A.