A clinical-grade HLA haplobank of human approximately 40% of the Japanese population

Background: Human induced pluripotent stem cells (iPSCs) are ex-pected to be useful for regenerative medicine for many diseases. Many researchers have focused on and enabled the generation of differentiated cells or tissue-like structures, including organoids, which help to ameliorate target diseases. To promote such cell therapies, we established a clinically applicable iPSC haplobank matching as many people as possible in Japan.Methods: Through cooperation with several organizations, we re-cruited donors whose human leukocyte antigens (HLAs) involved in im-munorejection were homozygous. The peripheral or umbilical cord blood collected from the donors was used for iPSC production by elec-troporation of episomal vectors. These iPSC lines were then subjected to testing, including genome analyses and sterility, to maximize safety.Findings: We constructed a clinical-grade haplobank of 27 iPSC lines from 7 donors according to good manufacturing practice regulations. However, reasons to avoid using iPSC lines include the presence of re-sidual episomal vectors or genetic mutations in cancer-related genes.Conclusions: This haplobank provides HLA-matched iPSC lines for approximately 40% of the Japanese population. Since the haplobank's release in 2015, these iPSC lines have been used in more than 10 clinical trials. The establishment of this haplobank is an important step toward the clinical application of iPSCs in cell therapies.

Automated summary

A clinically applicable iPSC haplobank has been established in Japan, consisting of 27 iPSC lines that match approximately 40% of the Japanese population. These lines have been used in over 10 clinical trials since their release in 2015.