Clonal Proliferation of Human Stimulated Lymphocytes on Agar Culture

Abstract

In order to investigate the process of proliferation, differentiation and maturation of hemopoietic cells, colony development of human bone marrow or peripheral blood cells has been studied. This was accomplished by the addition of stimulating factors or feeder layers which permit growth of colonies, such as macrophages monocytes, granulocytes and eosinophils to soft agar culture media (1–4). Clonal responses of lymphocytes in vitro have been described in a suspension culture medium where the lymphocytes were activated by mitogens (5–7). These clonal responses provide the rationale for the use of mitogens to stimulate a responsive human lymphocyte population to induce clonal proliferation of lymphocytes in a two layer soft agar system. The convenience of the soft agar method is the advantage of locating colonies, thus making possible the study of the conditions for formation of clones made up of cells originating from one precursor cell.