TCRgd Antibody [TCR-1] (PE)

The monoclonal antibody TCR-1 precipitates a heterodimer of Mr 90 kDa (two bands of Mr 50 kDa and 40 kDa upon reduction) on chicken peripheral blood T cells. Deglycosylation of the heterodimer yields two polypeptides of Mr 35 kDa and 32 kDa. Unlike human and mouse in which gammadelta cells comprise a minor subset of T lymphocytes in the circulation, the chicken has a relatively large subset of gammadelta T cells. The frequency of TCRgammadelta cells is typically 20-25% of the total blood T cells but may reach approximately 50% in chickens of six- months of age. The majority of TCRgammadelta+ cells in the thymus and blood are CD4-CD8- although a small subset of them may express CD8 or CD4 coreceptors. However, when the TCRgammadelta+ cells migrate into the spleen and intestine most of them begin to express CD8. Although the biological function of gammadelta T cells is unclear, they are clearly capable of cytotoxic activity in vitro. The CD8+ gammadelta T cells may also be involved in down-regulation of the immune response. They cannot, however, induce a graft-vs-host (GVH) reactions.