C18-4 spermatogonia cell line

The C18-4 cell line was generously provided by Dr. Marie-Claude Hofmann (MD Anderson Cancer Center, Huston, TX, USA). This cell line was established from type A spermatogonia obtained from testes of 6-day-old mice.25 The C18-4 cells express various markers for proliferating spermatogonia, and spermatogonial stem cells (SSCs), including germ cell nuclear antigen 1 (GCNA1), mouse ortholog of VASA, deleted in azoospermia-like (DAZL), proliferating cell nuclear antigen (PCNA), octamer-binding transcription factor 4 (OCT-4), glial cell line-derived neurotrophic factor family receptor alpha-1 (GFRA1), rearranged during transfection (RET), and promyelocytic leukemia zinc finger (PLZF).26 This cell line was used in several studies as a model for spermatogonia stem cells.26,27,28,29 The C18-4 cell line was grown in DMEM media with 5% fetal bovine serum (FBS; 16140-071; Thermo Fisher, Waltham, MA, USA), 5% bovine growth serum (SH30541.03, Thermo Fisher), 1% penicillin/streptomycin (15140-122, Thermo Fisher), and 0.5% Fungizone (15290-018, Thermo Fisher) at 37°C with 5% CO₂.