Epstein-Barr virus-induced lymphoblastoid cell lines derived from the peripheral blood of patients with X-linked agammaglobulinemia can secrete IgM.

We have established lymphoblastoid cell lines (LCL) from the peripheral blood of three individuals with X-linked agammaglobulinemia as well as three of their immunodeficient first-degree relatives. Lines could be induced with Epstein-Barr virus only when T lymphocytes were depleted from total mononuclear leukocytes. The LCLs derived from XLA patients expressed characteristics of IgM-secreting plasmacytes, including intense cytoplasmic fluorescence after staining with anti-mu, easily detectable amounts of IgM in culture supernatants, and radiolabeled IgM with both heavy and light chains in culture media and cell lysates. The cell lines induced from blood of the first-degree relatives of these patients were more varied. They often exhibited multiple isotypes for both heavy and light chains in different cells or expressed a B-lymphocyte phenotype (easily detectable surface Ig but no Ig secretion). These studies suggest that B-cell precursors are present in peripheral blood of individuals with classical XLA . Differentiation of such cells to mature cells of the B lineage can be accomplished using Epstein-Barr virus after removal of T cells.