新型工程碱性成纤维细胞生长因子提高稳定性，改善细胞培养结果

碱性成纤维细胞生长因子(bFGF，又称FGF2)在体外被广泛用于维持和刺激多种细胞。然而，天然bFGF在细胞生物学中的使用受到bFGF在生理温度下快速降解的限制;72小时后，我们发现原生bFGF活性< 20%。我们已经用一种工程形式的bFGF解决了这个问题，称为热稳定型bFGF (HS bFGF)，它在37摄氏度下稳定。HS bFGF在标准哺乳动物培养条件下72小时后仍保持>与原生蛋白90%的同源性和> 80%的活性。我们分别使用较低的bFGF浓度和更友好的工作流程，使用HS bFGF增强多能人类和大鼠神经干细胞(NSCs)的扩增。与原生bFGF相比，HS bFGF的使用也使两种模型的加倍时间缩短了约30%。重要的是，NSCs向神经元、星形胶质细胞和少突胶质细胞谱系的分化在HS bFGF和原生bFGF之间具有可比性。下游的分化表明，HS bFGF有能力在需要时完全从培养物中去除。HS bFGF还在三维(3D)培养中对MCF7人乳腺腺癌细胞的刺激进行了测试。 MCF7 spheroids were cultured in bFGF supplemented serum-free medium for 8 days without media changes so that spheroid morphology was undisturbed. Spheroids cultured in HS bFGF were perceptibly larger than those in native bFGF, starting just three days after seeding and continuing throughout the culture period. HS bFGF enhanced spheroid growth by almost 20% more than the native protein, as measured by PrestoBlue® assay. Because there was no need to change the media, we were also able to observe morphological changes to the spheroids that likely would have been impossible to document with a standard media change regimen. These data reinforce the idea that bFGF is a mitotic agent for MCF7 cells, a point which has previously been debated in the literature, and confirm that HS bFGF can provide stable stimulation in long-term culture. Taken together, these data show HS bFGF has broad applicability in cell biology and will be a valuable technology for a variety of applications moving forward. HS bFGF not only allows for reduced concentrations of bFGF to be used, but also enables a more user-friendly workflow for cell culture maintenance.