Studies on rabbit lymphocytes in vitro. V. The induction of blast transformation with sheep antisera to rabbit IgG subunits.

The addition of sheep antisera to rabbit IgG or to rabbit IgG subunits (L chain, H chain, Fab piece, Fc piece) to in vitro cultures of rabbit peripheral lymphocytes may induce up to 80-90% of the small lymphocytes to transform into immature "blast" cells. As many as 1 x 10(7) molecules of antibody may be required to stimulate each cell. It is concluded that each peripheral lymphocyte carries the antigenic specificities of the entire IgG molecule and thus could carry, and may produce specific antibody molecules. Such a conclusion supports the theory that the small lymphocyte may be the site of specific recognition of antigens in the primary response.