The use of cyclosporin A and azathioprine in clinical kidney transplantation.

The differential effects of CsA and AZA on the humoral immune responsiveness were studied in a separate study. After immunisation with inactivated influenza virus vaccine CsA treated kidney allograft recipients showed a significantly diminished antibody response to the T cell dependent influenza antigens. In contrast, the influenza vaccine induced antibody response in AZA treated patients did not differ from a group of healthy controls. From this thesis we can conclude that CsA and AZA have a different effect on cellular and humoral immune responsiveness. CsA therapy is complicated by renal dysfunction, hypertension, glucose intolerance and elevation of serum lipid levels, but all these sid~ effect are reversible after changing therapy to AZA. The CsA induced histologic lesions of the proximal tubular cells and arterioles also become less evident. After switching immunosuppressive therapy from CsA to AZA one year posttransplantation a new immunological balance is found, both in the peripheral blood and in the kidney allograft. Conversion at one year after transplantation is a safe procedure for first graft recipients preserving the benefits of longterm survival by CsA but it is contra-indicated for recipients of a second kidney allograft.