[The molecular parameters of a meningococcal serogroup B protein-polysaccharide vaccine]

Methods for the evaluation of the molecular parameters of B polysaccharide (B-PS) in meningococcal protein-polysaccharide vaccine of group B are proposed. The comparison of two proposed methods, the passive hemagglutination inhibition test and rocket immunoelectrophoresis (RIEP), has shown that the latter method has the highest degree of correlation with the chemical method of the detection of B-PS, which is often hindered by lactose added as a bulking agent. RIEP may be recommended for the standardization and control of the commercial preparations of group B meningococcal vaccine. B-PS contained in the vaccine is known to be in a highly polymeric state: its yield is 66.4 +/- 1.7% to Kd = 0.25 and 85.3 +/- 1.2% to Kd = 0.5. B-PS contained in the prepared vaccine has been found to be highly stable. Outer membrane proteins of meningococci, forming a noncovalent complex with capsular B-PS, seem to stabilize its structure and prevent the depolymerization of molecules.