Characterization of the Antibody for Vibrio Fetus Endotoxin in Sera of Normal and V. Fetus Infected Cattle

Abstract

Antibody for Vibrio fetus endotoxin has been demonstrated in sera from normal cattle of different ages. The V. fetus antibody resembles the “natural antibodies” described for other endotoxins in its specificity and in the uniformity of its distribution and concentration in serum. Antibody active in a passive hemagglutination reaction with lipopolysaccharide sensitized cells was associated almost exclusively with the γ1-macroglobulin component. Precipitating activity was localized mainly in the lower molecular weight globulins. Certain characteristics of the precipitins suggest that they may be γ1A-globulins. The presence of the venereal variety of V. fetus in bulls brought about no detectable change in quality or quantity of antibody. Venereal vibriosis in heifers led to the formation of serum precipitins more heat-stable than those in normal sera. In one animal which had aborted from vibriosis in the 6th month of gestation, precipitating and hemagglutinating activities were divided between the γ2- and γ1-macroglobulins.