ANALYSIS OF T-CELL REPERTOIRE AND FUNCTION IN MICE TRANSGENIC FOR THEHUMAN V(BETA)3 TCR

We have constructed mice containing the human V(beta)3 TCR gene from t he influenza virus haemagglutinin specific human CD4+ T cell clone HA1 .7. Similar cell yields were obtained from transgenic and non-transgen ic lymphoid tissue, with normal levels of T cells and with no unusual bias of the CD4 or CD8 subpopulations. Immunostaining and FACS analysi s of transgenic thymocytes, spleen, and mesenteric lymph nodes reveale d that the majority of T cells expressed the human V(beta)3 TCR on the cell surface. Small numbers of cells expressing murine TCRbeta chain were also detected. Polymerase chain reaction analysis revealed that a n extensive V(alpha) TCR repertoire was used in the human V(beta)3 tra nsgenic mice. Lymphocytes from the spleen and mesenteric lymph nodes o f transgenic mice were assessed for functional activity in vitro. isol ated cells were stimulated with mitogen or superantigen, as well as di rectly through the TCR - CD3 complex, and their ability to proliferate and secrete lymphokines analysed. Cells from transgenic mice responde d well after stimulation with phytohaemagglutinin, concanavalin A, ant i-CD3 antibody, anti-CD3 antibody with phorbol ester, and Staphylococc us aureus enterotoxin B, and also showed alloreactivity in a mixed lym phocyte reaction. Minimal levels of response were detected after stimu lation with murine TCRbeta antibody. Together, these data suggest that a human TCRbeta chain is able to associate with a murine TCRalpha cha in, to form a fully functional surface TCR - CD3 complex.