Acid phosphatase in lymphoid tissues of developing chick embryos.

Activity of acid phosphatase (ACPase) in bursa and thymus has been determined in developing chick embryos of either normal or treated with bovine serum albumin (BSA). From the study of light microscopical histochemistry, ACPase activity could be detected in cytoplasm. These ACPase activities were detected in both the follicular medulla and cortex in bursa. In thymus, moderate ACPase activities were also obtained in both the cortex and medulla. ACPase activity in the tissue homogenate was increased in the bursa but the thymic ones showed constant level during the incubation days examined in normal embryos. ACPase distribution observed at the distinct developing stage indicates that ACPase is a useful parameter for growth and development of chicken lymphoid tissues.