Leukaemic B-cell maturation: studies on immunoglobulin secretion mediated by two signalling systems in vitro.

The in vitro production and secretion of the immunoglobulins IgM, IgG, Kappa and lambda light chains by peripheral blood lymphocytes from chronic lymphocytic leukaemia patients was examined. The ELISA system was employed to quantitate the immunoglobulins secreted in the culture supernatants. Lipopolysaccharide and phorbol esters with CA++ ionophore were used as lymphocyte stimulators. The maturation of cultured lymphocytes was demonstrated by synthesis of cytoplasmic immunoglobulins and Ig secretions typical for plasma cells. In one case an isotype switch C mu for C gamma was observed.