In vitro RBC production from stem cells could represent an alternative to classic transfusion products. Until now the clinical feasibility of this concept has not been demonstrated. We addressed the question of the capacity of cultured RBCs (cRBCs) to survive in humans. By using a culture protocol permitting erythroid differentiation from peripheral CD34 ؉ HSC, we generated a homogeneous population of cRBC functional in terms of their deformability, enzyme content, capacity of their hemoglobin to fix/release oxygen, and expression of blood group antigens. We then demonstrated in the nonobese diabetes/severe combined immunodeficiency mouse that cRBC encountered in vivo the conditions necessary for their complete maturation. These data provided the rationale for injecting into one human a homogeneous sample of 10 10 cRBCs generated under good manufacturing practice conditions and labeled with 51

The molecular backgrounds of variants encountered in Afro-Caribbean black individuals and associated with the production of clinically significant antibodies against high-incidence antigens (anti-RH18, anti-RH34) and against Rhe epitopes were determined. We showed that RH:؊18 phenotypes are produced by 3 distinct RHCE alleles: ceEK carrying 48G>C (

The human ATP-binding cassette (ABC) transporter ABCB6 has been described as a mitochondrial porphyrin transporter essential for heme biosynthesis1, but is also suspected to contribute to anticancer drug resistance2–4, as do other ABC transporters located at the plasma membrane. We identified ABCB6 as the carrier of the blood group antigen Lan on red blood cells, but also at the plasma membrane of hepatocellular carcinoma (HCC) cells, and established that ABCB6 actually encodes a new blood group system (Langereis, Lan). Targeted sequencing of ABCB6 in 12 unrelated individuals of the blood type Lan− identified 10 different ABCB6 null mutations. This is the first report of deficient alleles of this human ABC transporter gene. Surprisingly, Lan− (ABCB6−/−) individuals do not suffer any clinical consequences, albeit their deficiency in ABCB6 may place them at risk when defining drug dosage.