The Enhancing Effect of Bone Marrow Cells on the Immune Response of Irradiated Mice Reconstituted with Spleen Cells from Normal and Immunized Donors

Abstract

Summary The injection of 5 million normal bone marrow cells into cobalt-60 irradiated mice produced a striking effect on the size of the spleen and greatly enhanced the number of antibody-forming cells found in the spleen 6 days after the injection of sheep RBC and small numbers of spleen cells from normal or preimmunized mice. The experiments are interpreted as indicating a nonspecific effect of bone marrow cells on the localization or proliferation of antibody-forming cells. They negate previous claims that bone marrow enhancement can be considered evidence for a multipotential antibody-forming cell precursor. Note Added in Proof: In the Proc. Nat. Acad. Sci., 59: 296, 1968, G. F. Mitchell and J. F. A. P. Miller reported experiments indicating that in the thymus-bone marrow interaction the antibody was made in a cell derived from the bone marrow. That is indeed a remarkable nonspecific effect. If it can be shown that in the interaction between normal bone marrow and immune spleen cell the antibody is made in the bone marrow cell, then this would raise the question of how the memory was transferred.