Bone marrow as a source of cells in reactions of cellular hypersensitivity. I. Passive transfer of tuberculin sensitivity in syngeneic systems.

Splenectomy or thymectomy of adult Lewis rats following sensitization with tubercle bacilli did not affect their ability to develop delayed skin lesions upon skin testing with PPD. The presence of the thymus also had no significant effect on reactivity of the recipients in passive transfer experiments. The passive transfer of tuberculin hypersensitivity with sensitized lymph node cells to thymectomized, irradiated recipients depended on the simultaneous or prior injection of normal bone marrow cells. When lymph node cell transfer was performed shortly after irradiation and injection of marrow, high doses of marrow cells (3.5-4.0 x 10(8) were required to permit eliciting reactions of reasonable intensity. If, however, periods of 7-10 days elapsed between the injection of bone marrow and sensitized lymph node cells, lower doses of marrow were sufficient for comparable reactions. Normal thymus, spleen, lymph node, or peritoneal exudate cells, even at high doses could not be substituted for the bone marrow in producing good tuberculin reactions.