Abstract: | The humoral immune response of Balb/c mice to live infective larvae or adult worm extract of Dipetalonema viteae is composed of two antibody populations either with or without specificity for phosphorylcholine. Absorption of immune serum on phosphorylcholine-Sepharose and separation of the antibody population demonstrated that anti-larvae serum contains a larger ratio of phosphorylcholine versus non-phosphorylcholine antibodies as compared to anti-adult serum. Immunofluorescence on crossections of female worms revealed that antigen expressing phosphorylcholine determinants were mainly found on certain internal structures, like egg, uterine, and intestinal membranes, but not on the cuticle. Immunoblotting using an adult worm extract demonstrated that protein bands reacted with either one or both populations of antibodies. The patterns were heterogeneous and moreover differed between the anti-larvae serum and the anti-adult serum. |