Alloreactive immune response

The alloreactive immune response is the adaptive (and sometimes innate) immunological reaction to foreign antigens within the same species (alloantigens), such such as mismatched HLA or blood antigens. It is primarily mediated by alloreactive T cells recognizing non-self MHC molecules through direct, indirect, or semi-direct allorecognition pathways, with roles for B cells (alloantibody production) and other immune effectors. This response is the main cause of transplant rejection, graft-versus-host disease, transfusion reactions, and certain maternal-fetal incompatibilities. Interventions to modulate alloreactivity form the foundation of clinical transplantation immunology. This entry refers to an immune response/process, not a discrete molecular or cellular therapeutic target such as a receptor, enzyme, or transporter.

Other names

alloreactivityalloimmune responsealloimmune reaction

Immunosuppression targeting T cells and/or B cells to prevent or reduce alloreactivity (e.g., via calcineurin inhibition, DNA alkylation, lymphocyte depletion). Treg-based tolerance induction.