Proliferation in autologous mixed lymphocyte reactions, expression of HLA-class II antigen and serum immunomodulatory activity in patients with renal insufficiency on chronic dialysis.

The proliferative and stimulatory capacities in allogeneic and autologous mixed lymphocyte reactions were evaluated in 5 patients affected by renal insufficiency undergoing maintenance hemodialysis. The expression of HLA class II antigens and Interleukin 2 production by PHA-activated T cells were also investigated. Furthermore the immunomodulatory effects of uremic serum and serum fractions on mixed lymphocyte reactions performed with lymphocytes from normal subjects were analyzed. The results show that both responsive and stimulatory capacities in allogeneic and autologous mixed lymphocyte reactions of non-T/T and T/T type are clearly impaired. The expression of HLA class II antigens by PHA-activated T cells was reduced whereas the production of Interleukin 2 was normal. The autologous and allogeneic mixed lymphocyte reactions of normal lymphocytes were inhibited by unfractionated uremic serum and by a wide range of serum fractions with different molecular weights. All the above mentioned immune defects were not corrected by the dialytic treatment. The present study extends previous reports concerning the defective immunocompetence associated with chronic renal insufficiency showing that: a) the autologous mixed lymphocyte reactions of both non-T/T and T/T type are impaired; b) the uremic serum contains several factors inhibiting the autologous mixed lymphocyte reactions of normal lymphocytes; c) the chronic hemodialytic treatment does not correct these defects.