Preparation of specific anti-thymocyte and anti-bursacyte sera in rabbits

A method of producing anti-thymocyte and anti-bursacyte sera in rabbits is described. Chickens which served as donors of cells were thoroughly perfused with saline to remove plasma proteins and circulating blood elements. For immunization, thymocytes were obtained from neonatally bursectomized birds, and bursacytes from chickens thymectomized at hatching. The purification of rabbit anti-lymphocyte sera included absorptions with leucocyte-free suspension of chicken erythrocytes, chicken liver cell membranes, thymocytes from bursectomized-irradiated and bursacytes from thymectomized-irradiated chickens, and chicken IgM and IgG immunoadsorbents. Cytotoxicity and fluorescent-antibody assays revealed that anti-thymocyte and anti-bursacyte sera thus produced clearly distinguished the surface antigenic determinants of thymocytes from those of bursacytes.