Impaired lymphocyte responses and their restoration in oral cancer patients expressing distinct TCR variable region.

We have analyzed TCR Vbeta gene usage and clonality of T cells in the peripheral blood of patients with oral cancer and healthy individuals. A large repertoire of clonal TCR Vbeta was observed in the peripheral blood of cancer patients, and this clonal expansion was dominantly represented in the CD8+ T cells. A marked decrease in the lymphocyte proliferative responses to mitogen and anti-CD3 MAb and spontaneous apoptosis was observed in lymphocytes. Appropriate co-stimulation of lymphocytes (anti-TCR Vbeta MAb and anti-CD28 MAb) restored the lymphocyte proliferative responses and CD3-zeta chain expression in these patients.