[Characteristics of the low molecular antigens of pertussis bacteria].

The authors elaborated a method of obtaining pertussis soluble antigenic complex by dialysis through the cellophane membrane against the physiological saline at a temperature of 4 degrees C. An antigen which was active in the passive hemagglutination and neutralization of antibodies tests was revealed in the dialyzate. The amount of this antigen in the dialyzate increased gradually up to the 7th day and then became stabilized. The serological activity of the antigen after evaportation increased 4-16 times. The results of the antibody neutralization test pointed to the presence in the dialysate of substances common to those contained in the 1a and 1Da fractions isolated from the pertussis bacteria with the aid of ammounium sulfate.