[Regulating role of the B-lymphocytes in lymphocyte interaction with allogeneic hematopoietic stem cells].

The preparative separation of lymph-node cells according to their charge and the study of the activity of each fraction have revealed that B-lymphocytes in the lymph nodes of mice have a regulating function in the phenomenon of the inactivation of allogeneic hematopoietic stem cells. The analysis of the dependence of effects, obtained in various experiments, on the ratio of B-lymphocytes and hematopoietic stem cells indicates that stem cells serve as targets for B-lymphocytes and the most probable mechanism of the above-mentioned effects is the direct interaction of the cells, one regulatory B-lymphocyte being capable of interacting with one target cell. Depending on the ratio of B-lymphocytes and stem cells, the inactivating effect may be either suppressed (the suppressor activity of B-lymphocytes) or enhanced (the helper activity of B-lymphocytes). The quantitative characteristics of the regulating activity of B-lymphocytes have been introduced.