[Role of thymus-dependent cells in splenic colony formation]

It was shown that treatment of the bone marrow with the serum reacting with the theta-antigen, irrespective of the presence of the complement, sharply decreases the capacity of its cells to form splenic colonies. Administration of the thymus cells together with the bone marrow to the recipient largely elminates the effect of this system, significantly increasing the splenic colony formation. It is supposed that the antiserum in the bone marrow inactivates the population of cells necessary for the formation of the colonies in the spleen, but differing from the pluripotent stem cells, possibly the population of T-cells.