Further studies of immunoglobulin synthesis by guinea pig leukaemic lymphocytes.

The L2C leukaemia is a B-lymphocytic neoplasm of strain 2 guinea-pigs, maintained by passaging in vivo. It synthesizes mu and lambda immunoglobulin chains. These combines to form monomeric (7S) IgM molecules which are inserted into the plasma membranes. From here they are shed as monomeric IgM and as a species of higher molecular weight which has not been further defined. The synthesis of lambda chain is in excess of that required for the IgM molecule, the surplus being exported directly from the cell without any intervening phase in the plasma membrane. Quantitative estimates of synthetic rates and pool sizes for these immunoglobulin species are presented.