[Changes in the surface structures of bacteria as a cause of weak immunogenicity of vaccines from several strains of Citrobacter]. / Izmenenie poverkhnostnykh struktur bakterii kak prichina slaboi immunogennosti vaktsin iz nekotorykh shtammov Citrobacter

The authors present the results of studying the weakly immunogenic Citrobacter strains; some O-antigens of Citrobacter (11, 14, 19, 21a, 21b, 26) caused in immunization of rabbits a weak immune response (antibody titre--1:400-1:800). An electron microscopic study of the vaccines (obtained from these strains) and their fragments showed that a partial desquamation and denaturing of the antigenic material occurred in the process of preparation of heated vaccines. Formalin-treated vaccine subjected to preliminary deflaggelation for 2 min at 3000 cps was used for obtaining the O-sera against the mentioned antigens.