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RBC substitutes: from the past to the future

The world is faced with an ever decreasing supply of blood products. Thus, studies on developing alternative blood substitutes have been continuously performed. During the 1960s, intravenous solutions and various artificial blood products were used during wartimes. For example, perfluorocarbon‐ and haemoglobin‐based oxygen carriers were developed as cell‐free oxygen carriers that could replace the function of red blood cells (RBCs). However, most of these carriers showed unsatisfactory results. In recent years, RBCs generated from stem cells appeared promising. Using haematopoietic stem cells, embryonic stem cells and induced pluripotent stem cells, enucleated RBCs with comparable function to donor RBCs could be harvested. However, many hurdles need to be overcome before RBC substitutes can be produced on a massive scale.