[Quantitative evaluation of Vibrio cholerae colonization and lymphocyte count in small intestine villi of rabbits immunized with vibrio and cholera toxin].

The influence of parenteral immunization with live virulent vibrios and lipopolysaccharide-containing choleragen toxoid and oral immunization with liver avirulent vibrios on the interaction of V. eltor and the mucous membrane was studied on the ligated loops of the small intestine in 164 rabbits. Protection from enterotoxigenicity (the accumulation of fluid) was compared with the suppressive effect on the adhesion and colonization of vibrios. The coefficient of immunization efficacy was determined microbiologically, as the ratio of the adhesion index (i. e. the percentage of the number of vibrios in the media inoculated with the homogenized matter of the washed intestinal wall from the sum of this number and the amount of vibrios in the contents) in the control rabbits to the adhesion index in the immunized ones, and histologically, as the ratio of the average number of vibrios attached to the epithelial number of vibrios attached to the epithelial cells of one intestinal villus in the control rabbits to the corresponding number in the immunized animals. Protection from the enterotoxigenicity of vibrios resulted from the suppression of their adhesion and colonization, lipopolysaccharide being, probably, the factor of adhesiveness. Effective protection was accompanied by an increase in the number of lymphocytes (especially "granular" lymphocytes with lysosome-like granules) between intestinal villi and the number of lymphoid and plasmic cells in the lamina propria of the villi, which indicates the role of lymphocytes in cholera-induced immunity.