IMMUNOLOGIE DE L'ENDOTHELIUM ET IMMUNOMODULATION DES ALLOGREFFES VASCULAIRES

The endothelial cells play a leading role both as effectors and targets of transplant rejection. The effector role is mediated by the specialised proteins of adhesion which are essential for recruitment in the graft of immunocompetent cells of the receiver. In addition, after stimulation by cytokines secreted by the immunitory cells of the host, the endothelial cells acquire the necessary properties to become immunogenic and contribute to maintaining the immunological reaction to the graft. They are target cells because they are particularly exposed to the humoral and cellular effectors of the rejection process, not only due to their strategic position at the interface between the grafted tissue and the blood, but also due to some of their intrinsic immunological properties. Vascular transplants are the object of renewed interest. The main obstacle to wider clinical application is their antigenicity. Also, vascular transplants are an excellent experimental mode for studying rejection and the efficacy of immunosuppressive or immunomodulating therapy. Classical immunosuppressive drugs and specific treatment directed against the immunocompetent cells of the graft or their interaction with effector cells of the host offer promising perspectives for reducing the antigenicity of these biological grafts.