[Immunological safety of transfusion].

Transfusion safety lies on the strict application of measures aimed: at avoiding the occurrence of acute hazards, as far as they can be prevented by e.g. the ABO compatibility for red blood cell concentrates and therapeutic plasma; at reducing the frequency of other acute accidents such as TRALI or post-transfusion GVH (based on the implementation of measures which prove to be largely efficacious though not completely); and at reducing delayed incidents and hazards. The implementation of such immunological safety measures also aim at favoring the transfusion efficacy, in avoiding the lysis of transfused red cells or platelets. Perfect immunological compatibility (match) is impossible because transfused cells expose several hundreds of molecular variants with antigenic properties. Adaptive immunity is largely based upon antigen/antibody conflicts and it predominates in transfusion immunological hazards, but inflammation (as well as other components of innate immunity) is now acknowledged as a major actor of transfusion immunological linked hazards.