Hyper Immunoglobulin M Immunodeficiency (Dysgammaglobulinemia): PRESENCE OF IMMUNOGLOBULIN M-SECRETING PLASMACYTOID CELLS IN PERIPHERAL BLOOD AND FAILURE OF IMMUNOGLOBULIN M-IMMUNOGLOBULIN G SWITCH IN B-CELL DIFFERENTIATION

• Text
• PDF

Abstract

The peripheral blood lymphocytes of nine patients with hyper immunoglobulin (Ig)M immunodeficiency were studied in an attempt to define the cellular basis of this disorder. B cells were normal in number but qualitatively abnormal in all patients. Approximately one-half of the B cell consisted of small lymphocytes (7-9 μm in diameter) bearing surface IgM and IgD, as well as C3 receptors. These cells were driven to secrete IgM but not IgG after in vitro stimulation by pokeweed mitogen. In the blood there were also large lymphocytes (10-14 μm in diameter) that possessed surface as well as intracytoplasmic IgM but lacked C3 receptors. These cells spontaneously secreted large amounts of IgM in vitro and on electron microscopy were found to be rich in rough endoplasmic reticulum. Such a subpopulation of lymphoid cells was not detected in normal peripheral blood and was unique for all patients with hyper IgM immunodeficiency studied.

Authors

Raif S. Geha, Newton Hyslop, Samih Alami, Fuad Farah, Eveline E. Schneeberger, Fred S. Rosen