Demonstration of the stability of the membrane phenotype of T helper cells after priming and boosting with a hapten-carrier conjugate.

Evidence is presented that the phenotype of the rat T helper cells is stable after priming and boosting with a hapten-carrier conjugate and that the phenotype is W3/25+, MRC OX-22-, MRC OX-8-. Data are also presented that demonstrate the presence of doubly marked, W3/25+, MRC OX-8+, cells in the spleens of rats primed 1 week previously.