[Immunologic characteristics of protein antigens of the Neiseriaceae family. III. Study of delayed hypersensitivity cross reactions between different species of Neisseria].

The immunological interrelations between the protein complexes of 34 strains of 12 species belonging to the family Neisseriaceae were studied with the use of delayed hypersensitivity reactions in specifically sensitized guinea pigs. No statistically significant differences between the nonpathogenic species of the family Neisseriaceae and the strains of N. haemolysans, n. cuniculi, N. lactamicus, N. ovis, N. elongata, N. cinerea were revealed. The preparations of Branhamella catarrhalis and N. caviae gave weak cross reactions with each other, as well as with other Neisseria. The probability and intensity of delayed hypersensitivity cross reactions depended on the degree of the immunological affinity of the preparations. The immunological similarity of protein complexes in most of the representatives of the family Neisseriaceae presents great possibilities for the development of sensitization to this group of microorganisms.