STUDIES ON RABBIT LYMPHOCYTES IN VITRO : VI. THE INDUCTION OF BLAST TRANSFORMATION WITH SHEEP ANTISERA TO RABBIT IGA AND IGM

Sheep antisera specific for the three major immunoglobulin groups of the rabbit, i.e. IgG (γ-chain), IgA (α-chain), and IgM (µ-chain), are each able to induce blast transformation of the peripheral lymphocytes of the rabbit when added to in vitro cultures. The per cent of lymphocytes transformed with each antiserum indicate that one-fourth of the peripheral lymphocytes carry or have the capacity to synthesize molecules of all three of the major immunoglobulin groups, and that the remaining three-fourths carry or have the capacity to synthesize only two (IgG and IgM). The data do not permit direct conclusions concerning the ability of a single cell to produce molecules belonging to more than one immunoglobulin group at the same time, or the ability of a given cell to make a transition from the synthesis of molecules of one immunoglobulin group to those of another group.