Blood transfusion-related immunomodulation

The phenomenon of transfusion-related immunomodulation (TRIM) has been studied since the observation of a higher kidney allograft survival in patients who had received a higher number of transfusions. Conversely, it has been suggested as one of the possible causes related to the development of infections in patients with multiple blood transfusions and/or after a major surgery, and has been also associated with a decreased function of natural killer cells (NK) and antigen-presenting cells (APCs), reduced cell-mediated immunity, and increased regulatory T cells (Tregs). This review aimed to conceptualize TRIM and discuss some aspects related to its mechanisms and the prevention of immunomodulatory events.