Rabbits possess conventional T lymphocytes.

Rabbit lymphocytes have been analyzed as to surface Ig markers in relation to the function of the cells. A battery of specific anti-Ig reagents as well as supposed B and T cell-specific mitogens were used, and DNA synthesis as well as high-rate Ig synthesis in vitro were recorded. Using cells from spleen lymph node or blood, surface Ig-negative lymphocytes expressed the expected behavior of T lymphocytes. No evidence was found of significant expression of allotypic markers on the surface of such nonactivated rabbit T lymphocytes. Lymphoid cells from bone marrow constituted an exception to the rule in the sense that they contained a high proportion of cells being surface Ig-negative at the time of anti-Ig column fractionation. They did, however, rapidly express surface Ig molecules as well as B cell markers as judged by B cell mitogenic stimulation shortly after in vitro explanation. In conclusion, we failed to find any constant region Ig markers on rabbit lymphocytes, which in every sense behave like conventional T lymphocytes.