Humoral immune response after kidney transplantation is enhanced by acute rejection and urological obstruction and is down-regulated by mycophenolate mofetil treatment.

The anti-allograft immune response may have a cellular and a humoral component. Lymphocytotoxic antibodies (Ab) and anti-human leucocyte antigen (HLA) Ab present before kidney transplantation carry an enhanced risk of acute rejection. Current immunosuppressive drugs act predominantly upon the cellular immune pathway which may leave unopposed the humoral mechanisms of anti-allograft response.