Anti-interleukin-2 receptor antibodies: basiliximab and daclizumab

At present, classical induction therapy is inadvisable for low‐risk renal transplantation (RT) recipients, given the efficacy of immunosuppressive regimens based on micro‐emulsified cyclosporin, tacrolimus, MMF, or sirolimus and the risk of infections and malignancies [1]. The classical induction is more questionable for high immunological risk patients. Monoclonal antibodies against IL‐2 receptor (IL‐2r) offer the possibility of more selective immunosuppression. Murine anti‐IL‐2r antibodies significantly reduce the incidence of early acute rejection without any relevant associated toxicity [2]. However, they stimulate a potent immune response in the human recipient that limits their use at medium or long‐term, exhibit a half‐life and are inefficient to destroy human cells. Basiliximab is a chimeric monoclonal antibody (murine/human) with human IgG1 constant heavy chain regions and kappa light chain. It specifically binds and blocks CD25 antigen, IL‐2r α‐chain, at the surface of activated T‐lymphocytes [3]. This specific basiliximab binding to IL‐2r competitively inhibits IL‐2 mediated lymphocyte activation, a crucial phase in cellular immune response of allograft rejection.