Production of TL antibody by mice immunized with TL- cell populations. A possible assay for thymic hormone

TL(-) mice make TL antibody when immunized with spleen or bone marrow cells from TL(+) donors, despite the fact that these cells do not express TL antigen. This has been shown to depend on maturation of TL(-) precursors, contained in the inoculum, into TL(+) cells under influence of the recipient's thymus; the differentiated TL(+) cells then evoke production of TL antibody.