Antigenic surface determinants of chicken lymphoid cells. II. Selective in vivo and in vitro activity of anti-bursa and anti-thymus sera.

Appropriately absorbed turkey antisera to antigenic surface determinants of chicken bursa (ABS) or thymus cells (ATS) were assessed for their selective immunosuppressive activy in vitro and in vivo. The intraperitoneal injection of ABS or ATS into 2-3-week-old normal white Leghorn chickens entailed a significant depletion of B or T cells respectively from spleen and peripheral blood, while bursa and thymus themselves remained unaffected. The potential of this 'peripheral serological bursectomy and thymectomy' paralleled that found after the conventional surgical procedures with subsequent sublethal irradiation. The mean survival time of skin allografts from donors of genotype B4B4 onto B8B8 recipients was significantly prolonged by treatment with ATS (29 plus or minus 12 days) as compared to untreated (14 plus or minus 2 days), normal turkey serum (12 plus or minus 3 days) or ABS-injected (13 plus or minus 2 days) groups. This selective suppression of a T cell-dependent immune reaction by ATS was also confirmed in vitro by its inhibitory action on the graft-versus-host reactivity of adult peripheral blood lymphocytes in the chorioallantoic membrane assay, where normal turkey serum and ABS were again ineffective. Thus, ABS or ATS produced in avian species may serve not only to delineate B and T cells in vitro, but can also be used for selective manipulation of immune reactions of the chicken in vivo.