IMMUNOGLOBULIN-SECRETING CELLS IN LYMPHOCYTES OF PATIENTS WITH IGA DEFICIENCY OR HYPER-IGA

To assess the ability of immunoglobulin production in vivo, we enumera ted the immunoglobulin secreting cells in the peripheral blood of pati ents with an IgA deficiency and of those with hyper-IgA-emia. All seve n patients with primary IgA deficiency and two of the three patients w ith secondary IgA deficiency had low numbers of IgA secreting cells. I n all five patients with hyper-IgA the number of IgA secreting cells w as increased. Our results suggest that measurement of immunoglobulin s ecreting cells in PBMCs is useful in the assessment of ability of immu noglobulin production in vivo.