CD140b and CD73 are markers for human induced pluripotent stem cell-derived erythropoietin-producing cells

Renal anemia in chronic kidney disease is treated with recombinant human erythropoietin (rhEPO). However, some patients with anemia do not respond well to rhEPO, emphasizing the need for a more biocompatible EPO. Differentiation protocols for hepatic lineages have been modified to enable production from human induced pluripotent stem cell (hiPSC)-derived EPO-producing cells (EPO cells). However, markers for hiPSC-EPO cells are lacking, making it difficult to purify hiPSC-EPO cells and therefore to optimize EPO production and cell counts for transplantation. To address these issues, we investigated whether CD140b and CD73 could be used as markers for hiPSC-EPO cells. We measured the expression of EPO, CD140b, and CD73 in hiPSC-EPO cells and the EPO concentration in the cell supernatant by immunohistochemistry and enzyme-linked immunosorbent assays on culture day 13, revealing that expression levels of CD140b and CD73 are correlated with the level of EPO. In addition, rates of CD140b⁺ CD73⁺ cells were observed to be correlated with the concentration of EPO. Thus, our results suggest that CD140b and CD73 may be markers for hiPSC-EPO cells.