B cells in the appendix and other lymphoid organs of the rabbit: complement receptor lymphocytes.

Complement receptor lymphocytes were demonstrated in rabbit lymphoid organs, the spleen containing the highest numbers (35%) and the thymus none. Extremely variable numbers (up to 50%) were detectablein the appendix. B and T cell depletion, rosette depletion, and histologic staining indicate that these CRL are B cells in the rabbit as in other species. The variable behavior of B cells in the appendix suggests a difference between this lymphoid organs population and those of other rabbit lymphoid organs.