Abolition of allogeneic inhibition and changes in differentiation of mouse bone marrow colony-forming cells by syngeneic lymphocytes

A mixture of bone marrow cells and lymph gland lymphocytes of C57BL mice was injected intravenously into F₁ (A×C57BL) mice irradiated in a dose of 850 R. Under the influence of syngeneic lymphocytes of the C57BL mice colony-forming cells (CFUs) of the bone marrow proliferated in the F₁ mouse hybrids as if they had been in a syngeneic organism. Besides restoration of the number of CFUs capable of forming colonies in a genetically foreign organism, under the influence of lymphocytes the colonies changed their direction of differentiation, with an increase in the number of granulocyte colonies. This process was accompanied by the development of a blast transformation reaction and by hyperplasia of the lymphoid tissue of the recipients' spleens.