In vivo neutralization of anti‐A and successful transfusion of A antigen–incompatible red blood cells in an animal model

BACKGROUND: Our aim was to determine if the historical principle of Lewis glycolipid neutralization of antibody and subsequent Lewis-incompatible transfusion could be extended and applied to the ABO blood group system using synthetic glycolipid-like constructs. STUDY DESIGN AND METHODS: In vitro experiments with human blood and blood group A function-spacer-lipid constructs (FSL-A) were used to determine rates and concentrations that caused antigen transformation and anti-A neutralization. FSL-A constructs were intravenously infused into naive and anti-A-immunized mice to determine in vivo antigen transformation, anti-A inhibition, and tolerance to A antigen-incompatible transfusions (A+biotin kodecytes). RESULTS: FSL-A was able to cause in vivo transformation of circulating mouse cells into A antigen-positive cells (in vivo A kodecytes) without consequence in animals either with or without circulating anti-A. FSL-A was able to neutralize circulating anti-A and allow for successful transfusion of incompatible A kodecytes. In the absence of FSL-A neutralization incompatible cells were rapidly destroyed. CONCLUSIONS: FSL constructs have the potential to neutralize circulating antibodies and allow for, or mitigate, the consequences of ABO-incompatible red blood cell transfusion.