Transplantation of lymphoid cells into immunodeficient chickens: Dissociation in the reconstitution of B and T cell functions

Abstract

Chicks were treated with cyclophosphamide (CY) in the newly hatched period and, at the age of 4.5 wk, transplanted with histocompatible cells from bursa of Fabricius, spleen, bone marrow, or thymus. Immediate antibody production to sheep red blood cells and Brucella abortus, and long-term restoration (5–6 wk) of antibody formation, mortality, gain of body weight, and lymphocyte responses to phytohemagglutinin and concanavalin A were used to assess the effect of transplantation. No evidence for a long-term uptake of transplanted cells was obtained, if no pretreatment was given to the recipients before the transplantation, or if the recipients were pretreated with CY (100 mg/day/kg of body weight given on the two preceding days). Only when the recipients were X-irradiated (750 rads) on the day before the transplantation, a significant decrease in the mortality, increase in the gain of body weight, and restoration of lymphocyte response to concanavalin A was observed after transplantation of spleen cells of 10-wk-old donors. No evidence in any instance for a long-term restoration of antibody formation was achieved. For this purpose, same kind of cell preparations were used, which induce a vigorous reconstitution of the bursa-dependent immunity, when transplanted into newly hatched CY-treated recipients. These findings are interpreted to indicate that a proper function of the vitally important T cell system is guaranteed before that of B cell system whenever possible. A barrier for transplantation of syngeneic cells, as described in the mouse, probably exists also in the chicken, and the barrier is different for the T cell line than for the B cell line. The syngeneic resistance, increasing with age, makes the age of cell recipients an important factor to be considered in the transplantation of lymphoid cells.