Tissue distribution and appearance in ontogeny of alpha/beta T cell receptor (TCR2) in chicken.

We have performed immunoperoxidase staining on cryostat tissue sections and immunofluorescence analysis on cell suspensions to identify cells expressing the alpha/beta T cell antigen receptor during ontogeny and adult life in chickens. We used the mouse monoclonal antibody, TCR2, which was previously shown to recognize the alpha/beta TCR in chickens. TCR2+ cells were observed in thymic cortex and medulla and in T-dependent areas of spleen, intestine, and cecal tonsils of young adult chickens. Some TCR2+ cells were found in the cortex of bursal follicles and in liver. The first TCR2+ cells appear in thymus on Day 13 of the embryonic life and it is only after hatching that TCR2+ cells begin to migrate to the periphery.