Immunological alterations in haemophiliacs treated with lyophilized Factor VIII cryoprecipitate from volunteer donors.

We studied immune function in Belgian haemophiliacs treated with Factor VIII from volunteer donors. No patient had clinical evidence of immune deficiency. We found a decrease in T-helper cells (p less than 0.0005), in the ratio of T-helper over T-cytotoxic/suppressor cells (1.72 +/- 0.47 versus 2.24 +/- 0.82 in controls, p less than 0.005) and in lymphocyte responsiveness to mitogens (p less than 0.05). These findings could not be linked to the amount of F VIII received over the last year, the time since last F VIII administration, circulating immune complexes (54% positive patients, 7% positive controls, p less than 0.005), increased ALT levels, antibodies to cytomegalo -virus (85% of the patients, 45% of the controls, p less than 0.005), antibodies to Epstein-Barr virus, nor to the presence of HLA-DR 5 which was found in 56% of the haemophiliacs (20% of the overall Belgian population, p less than 0.005). Either F VIII induces long lasting immunological alterations unrelated to AIDS, or haemophilia is itself associated with such changes.