Surgery Transplantation 4c4d6bb0 Hyper acute rejection is due to: A Preformed antibodies B Cytotoxic T-lymphocyte medicated injury C Circulating macrophage mediate injury D Endothelitis caused by donor antibodies High-Yield Explanation Ans. (a) Preformed antibodiesRef: Bailey 26th edition, Page 1412* Hyperacute happens in minutes to hours due to preformed antibodies.