Summary
We measured numbers of lymphocytes and subsets in seven HIV negative, HCV positive
severe haemophilia B patients, before and after substitution was changed from prothrombin
complex concentrate to monoclonally purified concentrate. Data were compared with
controls and our previous findings in haemophilia A.
At baseline, haemophilia B patients did not differ from controls. After two years,
T helper cells showed an increase (p = 0.028), while a rise in B cells approached
statistical significance (p = 0.063). Haemophilia A patients showed increased numbers
of activated non-B lymphocytes (p = 0.003) and lowered numbers of B cells (p = 0.001)
at baseline. After two years activated non-B lymphocytes decreased (p = 0.004), as
did the CD4/CD8 ratio (p = 0.002), due to increasing numbers of CD8 positive cells
(p = 0.087).
Our data suggest minor inhibition of the immune system in haemophilia B patients,
which recovers after changing therapy to a monoclonally purified product. These findings
contrast with the excessive immune stimulation in haemophilia A. The observed differences
might be due to the administered concentrates.
