Decreased B cells and IgA-secreting B cells partially explain the high prevalence of IgA deficiency in dialysis patients.

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We previously reported 2 hemodialysis (HD ) patients with recurrent infections and selective immunoglobulin A deficiency (IgAD ). We further demonstrated that serum IgA levels were lower and the prevalence of IgAD was higher in uremic patients . The exact mechanisms of IgAD in uremic patients largely remained unclear . In some patients , it was caused by anti-IgA antibody neutralization and subsequent destruction . We performed the present study to survey if there is any defect in IgA production .288 patients were initially included for examination of serum immunoglobulins . 16 normal persons , 16 dialysis patients without IgAD , and 12 dialysis patients with IgAD were enrolled after the initial examination . Blood was drawn into heparinized tubes . WBC counts and lymphocyte percentage were examined by a CBC counter . Lymphocytes were separated by the Ficoll-Paque method . Flow cytometry was utilized to isolate the B cell and IgA-secreting B cell after staining with CD 19 phycoerythrin and FITC-conjugated rabbit anti-human IgA antibody .There is no significant difference between WBC counts or total lymphocyte counts of these 3 groups . However , we found a lower percentage of total lymphocyte counts in dialysis patients , either with or without IgAD . The total B cell numbers were lower in dialysis patients with IgAD . In addition , there were fewer IgA-secreting B cells in dialysis patients with IgAD .Decreased B cell and IgA-secreting B cell counts are seen in uremic patients with IgAD . This , in turn , indicates that there might be a defect of IgA production in some patients , rather than IgA destruction by anti-IgA antibodies as seen in some other patients . Further study is needed to investigate the mechanisms of decreased B cells and IgA-secreting B cells .