Localization of T- and B-Iymphocytes in the lymphoid organs of chicken embryo and assessment of their functional status

Present study was conducted to investigate the localization of two important components of humoral and cell mediated immunity, i.e. T- and B-lymphocytes and assessment of their functional status in developing chicken embryo using monoclonal markers and immunoperoxidase staining technique. T-cells were demonstrated in thymic cortex and B-cells in bursal follicles. In spleen T-cells were found around the arterial blood vessels with B-cell colonies in between. Both T- and B-cells were not responsive to mitogenic stimuli at 16^th day of incubation, but their response was very high at 21^st day of incubation. This showed that however, lymphocytes are differentiated into T- and B-lymphocytes at 16^th day of incubation, but they start functioning at 21^st day of incubation.