In vivo preferential usage of TCR V/gb8 in Torpedo acetylcholine receptor immune response in the murine experimental model of myasthenia gravis

The aim of our study was to determine the T cell receptor (TCR) Vβ gene usage involved in the T cell response to Torpedo AChR in C57BL/6 mice. The specific proliferation towards AChR was found to be blocked by anti-Vβ8.1,2,3 and to a lesser extent by anti-Vβ5 mAbs, but not by the other antibodies used (anti-Vβ2, Vβ6, Vβ9). In addition, a significant expansion of CD4+Vβ8+ cells was observed when lymph node cells from these primed mice were stimulated in vitro with purified AChR. Involvement of Vβ8 subfamilies was also explored in vivo. After 7 days of treatment, there was a striking inhibition of the proliferative response of cells from anti-Vβ8.1,2,3-treated mice and a moderate inhibition when using anti-Vβ.1,2 and anti-Vβ8.2 antibodies. Thus our in vitro and in vivo analysis indicate that in C57B1/6 mice, T cell response to AChR is restricted to few Vβ TCR, mostly belonging to the V;38 sub-families.