Two monoclonal antibodies specific for the T cell receptor Vα8

Abstract
Two monoclonal antibodies, KT50 and KT65, specific for Vα8 have been established. This was determined as follows: (a) 4 T cell clones, C6, R1, G22 and 19, out of 43 T cell clones with various antigen specificities, major histocompatibility complex restrictions and Vβ usages not only bound KT50 and KT65 but also expressed Vα8 mRNA, (b) KT50 and KT65 precipitated molecules from the clone C6 similar to the T cell receptor molecules precipitated in C6 cells by KT11 (anti‐Vβ11) or KTL2 (anti‐Ti) and (c) KT50 and KT65 were mitogenic and induced cytotoxicity. All strains of mice so far examined have populations of KT50+ and KT65+ T cells of 1.4%−3.6% and 0.9%−2.6%, respectively. Different H‐2 haplotypes were not observed to affect the number of cells expressing KT50 or KT65. In addition KT15 (anti‐CD8), without cross‐linking to KT50 or KT65, augmented proliferation triggered by KT50 or KT65.