Biosynthesis and secretion of immunoglobulins by peripheral blood lymphocytes in severe hypogammaglobulinemia and by cultured lymphoblast cells.

Peripheral blood lymphocytes of two patients with infantile X-linked agammaglobulinemia could neither synthesize nor secrete immunoglobulins in detectable amounts. Peripheral blood lymphocytes of patients with common variable type of hypogammaglobulinemia synthesize but do not secrete immunoglobulins. Serologic precipitation with antiimmunoglobulin serum and acrylamide-gel analysis of immunoglobulins synthesized by lymphocytes of these patients showed predominant mu-chain, as compared to immunoglobulins synthesized by normal lymphocytes. Biosynthesis and secretion of immunoglobulins by cultured lymphoblast cells from normal persons was very much analogous to that of lymphocytes of hypogammaglobulinemic patients. These findings suggest that lymphocytes of patients with common variable type of hypogammaglobulinemia are immature B cells like cultured lymphoblast cells, and that a block in cytodifferentiation of IgM to IgG-producing cells is present in their B cells.