Proliferative responsiveness of B cells in primary immunodeficiency

Proliferative responsiveness of B cells from 7 patients with primary immunodeficiency was studied. The used mitogens were F (ab')2 fragment sheep anti-human IgGF (ab')2 fragment (ã-IgGF(ab')2), Staphylococcus aureus Cowan I (STA) and Epstein Barr virus (EBV). The results obtained are as follows. 1) In common variable hypogammaglobulinemia (3 cases), B cells from 2 patients showed markedly decreased responses to all the used mitogens, while those from one patient showed normal responses. The decreased responses to mitogens were not restored by depletion of adherent cells. 2) In IgA-deficiency (2 cases), B cells from one patient associated with juvenile rheumatoid arthritis showed decreased responses to all the mitogens, while those from the other showed normal responses. 3) In immunodeficiency with hyper IgM (one case) and IgM-deficiency (one case), the mitogen responses of B cells were almost normal except the slight decreased response to STA.