Suppression of Rabbit Lymph Node Cells by Rabbit Anti-Leucocyte Serum Demonstrated in Vitro by the Antibody Plaque Test

[摘要] The production of hemolytic antibody plaques by lymph node cells of rabbits injected with sheep erythrocytes can be inhibited by prior incubation of the cells with rabbit anti-rabbit-leucocyte serum and complement. The 50% plaque reduction endpoint of such sera is, over a wide range, inversely proportional to the concentration of the lymph node cell suspension used. This reduction of plaque number can be inhibited by prior incubation of the rabbit anti-rabbit-leucocyte serum with solubilized preparations of the cell antigen associated with the rejection of transferred allogeneic cells.The identity of the antibody causing reduction in number of plaques by allogeneic lymph node cells with the antibody causing reduction of antibody production by such cells when transferred to recipient rabbits has been indicated in two ways. First, in a number of rabbit anti-rabbit-leucocyte serum pools, endpoints obtained by the two methods showed a high degree of correlation, with a 45° line of regression between them. Second, when rabbits were injected with the soluble rejection-associated antigen, and the resulting antisera, individually tested by plaque reduction, were selected on that basis for pools of relatively high and low suppressive activity, the two pools, on subsequent testing in cell-transfer experiments, showed sharp differences in suppressive effect on transferred lymph node cells, in conformity with the activity of the sera in plaque-reduction.In rabbits actively immunized with the rejection-associated antigen and then used as recipients in cell transfer, it was possible to predict roughly the degree of suppression of transferred lymph node cells in these recipients by the plaquereduction titer of the sera of the individual rabbits obtained shortly before cell transfer.

[学科分类] 生物科学（综合）