Development of a novel in vitro micronucleus test using human induced pluripotent stem cell-derived T lymphocytes

Various immortalized cells and human fresh blood lymphocytes have been used in in vitro genotoxicity studies (e.g., micronucleus (MN) test). Although immortalized cells can be supplied stably, their properties are different from normal cells such as abnormal karyotype. Human fresh blood lymphocytes are representative human normal cells, but homogenous lymphocytes are difficult to supply stably and in a timely manner due to individual differences between donors. Here, we aimed to develop a novel in vitro MN test using human induced pluripotent stem cell (hiPSC)-derived T lymphocytes to overcome the above problems.

hiPSCs were differentiated to T lymphocytes, which were confirmed to possess the ability to grow well in culture, a normal karyotype, and a spontaneous frequency of micronuclei. The genotoxicity of several reference positive / negative control substances was evaluated. The responses for all test substances, including clastogen, aneugen and negative substances, were consistent with published reports.

Our results demonstrated promising proof-of-principle data as an in vitro MN test and suggest that hiPSC-derived T lymphocytes have a potential to make a significant contribution to the improvement of in vitro genotoxicity studies.