Human amniotic epithelial cells maintain mouse spermatogonial stem cells in an undifferentiated state due to high leukemia inhibitor factor (LIF) expression.

Spermatogonial stem cells (SSCs), like other stem cells, have unique properties: prolonged proliferation, self-renewal, generation of differentiated progeny, and maintenance of developmental potential. Long-term cultivation of normal SSCs into stable cell lines, and maintaining SSCs in an undifferentiated state capable of self-renewal, is a major challenge. Here, we compare the effect of leukemia inhibitory factor (LIF) expression on mouse SSCs isolated from testicular tissue cultured under different conditions. We found that human amniotic epithelial cells (hAECs) with high LIF expression (LIF high ) feeder cells allowed mouse SSCs to maintain a high level of AP activity when cultured long term. Expression of some important stem cell markers was higher in mouse SSCs cultured on hAECs (LIF high ) compared to those cultured on hAECs (LIF low ). Taken together, these results suggest that LIF expression could be a crucial component for feeder cells to maintain mouse SSCs in an undifferentiated, proliferative state capable of self-renewal.