Murine 3T3 cell lines constitute a standard model system for in vitro study of mammalian adipogenesis although they do not faithfully reflect the biology of the human adipose cells. Several human adipose cell lines and strains have been used to recapitulate human adipogenesis in vitro, but to date there is no generally accepted in vitro model for human adipogenesis. We obtained a clonal strain of human subcutaneous adipose stromal cells, IPI-SA3-C4, and characterized its utility as an in vitro model for human subcutaneous adipogenesis. IPI-SA3-C4 cells showed a high proliferative potential for at least 30 serial passages, reached 70 cumulative population doublings and exhibited a population doubling time of 47 h and colony forming efficiency of 12% at the 57th cumulative population doublings. IPI-SA3-C4 cells remained diploid (46XY) even at the 56th cumulative population doublings and expressed the pluripotency markers POU5F1, NANOG, KLF4, and MYC even at 50th cumulative population doublings. Under specific culture conditions, IPI-SA3-C4 cells displayed cellular hallmarks and molecular markers of adipogenic, osteogenic, and chondrogenic lineages and showed adipogenic capacity even at the 66th cumulative population doublings. These characteristics show IPI-SA3-C4 cells as a promising potential model for human subcutaneous adipogenesis in vitro.

鼠3T3细胞系虽然不能如实反映人类脂肪细胞的生物学特性，但却构成了用于体外研究哺乳动物脂肪形成的标准模型系统。几种人类脂肪细胞系和菌株已用于体外概括人类脂肪形成，但迄今为止，尚无普遍公认的人类脂肪形成体外模型。我们获得了人皮下脂肪基质细胞IPI-SA3-C4的克隆菌株，并表征了其作为人皮下脂肪形成体外模型的效用。IPI-SA3-C4细胞显示出至少30次连续传代的高增殖潜能，达到了70倍的累积种群倍增，并且显示了47 h的种群倍增时间，在第57次累积种群倍增时显示出12％的菌落形成效率。POU5F1，NANOG，KLF4和MYC甚至在第50个累积人口增加一倍时。在特定的培养条件下，IPI-SA3-C4细胞显示出成脂，成骨和成软骨谱系的细胞标志和分子标记，甚至在第66个累积种群倍增时也显示出成脂能力。这些特征表明，IPI-SA3-C4细胞是体外人皮下脂肪形成的有前途的潜在模型。