TY - CHAP M1 - Book, Section TI - Solid Organ Transplantation A1 - Park, Jeong M. A1 - Shaikh, Suhail A. A2 - Sutton, S. Scott Y1 - 2020 N1 - T2 - McGraw Hill’s NAPLEX® Review Guide, 4e AB - Rejection is a primary barrier to the success of solid organ transplantation. There are three types of graft rejection that can occur after solid organ transplantation: antibody-mediated, acute cellular, and chronic rejection. Antibody-mediated rejection (AMR) is mediated by donor-specific antibodies against human leukocyte antigens or other antigens, and typically occurs intraoperatively or within days after receiving an ABO blood type mismatched or positive crossmatch organ transplantation. Strategies used to prevent AMR include avoiding mismatched transplants or desensitizing recipients with known detectable donor-specific antibodies prior to transplantation. These strategies are critical, as treating ANR remains challenging. Acute cellular rejection (ACR) is the most common type of rejection and is generally reversible with appropriate diagnosis and timely treatment. It results from an orchestrated immune response that involves alloantigen presentation by antigen presenting cells that leads to alloreactive T cells. The cytotoxic T cells infiltrate the graft and cause direct tissue damage, whereas the helper T cells produce cytokines to cause subsequent immunological and inflammatory events. Although ACR can occur anytime, the risk is highest in the first several months after transplantation. Prevention and treatment of ACR is of utmost importance, as it is a significant predictor of chronic rejection. The exact etiology of chronic rejection is unknown. It is a slow process of graft fibrosis and arteriopathy, which results in graft dysfunction, usually manifested years after transplantation. While ACR can be treated pharmacologically, the only therapy for chronic rejection is retransplantation. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/03/29 UR - accesspharmacy.mhmedical.com/content.aspx?aid=1179733731 ER -