Woodley Joe P, Lambert Daniel W, Asencio Ilida Ortega
The School of Clinical Dentistry, University of Sheffield, Sheffield S10 2TA, UK.
Bioengineering (Basel). 2023 Mar 11;10(3):348. doi: 10.3390/bioengineering10030348.
In vivo, quiescent fibroblasts reside in three-dimensional connective tissues and are activated in response to tissue injury before proliferating rapidly and becoming migratory and contractile myofibroblasts. When deregulated, chronic activation drives fibrotic disease. Fibroblasts cultured on stiff 2D surfaces display a partially activated phenotype, whilst many 3D environments limit fibroblast activation. Cell mechanotransduction, spreading, polarity, and integrin expression are controlled by material mechanical properties and micro-architecture. Between 3D culture systems, these features are highly variable, and the challenge of controlling individual properties without altering others has led to an inconsistent picture of fibroblast behaviour. Electrospinning offers greater control of mechanical properties and microarchitecture making it a valuable model to study fibroblast activation behaviour in vitro. Here, we present a comprehensive characterisation of the activation traits of human oral fibroblasts grown on a microfibrous scaffold composed of electrospun polycaprolactone. After over 7 days in the culture, we observed a reduction in proliferation rates compared to cells cultured in 2D, with low KI67 expression and no evidence of cellular senescence. A-SMA mRNA levels fell, and the expression of ECM protein-coding genes also decreased. Electrospun fibrous scaffolds, therefore, represent a tuneable platform to investigate the mechanisms of fibroblast activation and their roles in fibrotic disease.
在体内，静止的成纤维细胞存在于三维结缔组织中，在组织损伤时被激活，然后迅速增殖，转变为具有迁移和收缩能力的肌成纤维细胞。当调控失调时，慢性激活会引发纤维化疾病。在坚硬的二维表面培养的成纤维细胞呈现出部分激活的表型，而许多三维环境则会限制成纤维细胞的激活。细胞的机械转导、铺展、极性和整合素表达受材料的机械性能和微观结构控制。在三维培养系统中，这些特征变化很大，在不改变其他特性的情况下控制单个特性的挑战导致了成纤维细胞行为的描述不一致。静电纺丝能更好地控制机械性能和微观结构，使其成为体外研究成纤维细胞激活行为的有价值模型。在此，我们全面表征了在由静电纺聚己内酯组成的微纤维支架上生长的人口腔成纤维细胞的激活特性。培养7天以上后，我们观察到与二维培养的细胞相比，其增殖率降低，KI67表达水平低，且无细胞衰老迹象。α-平滑肌肌动蛋白（A-SMA）的mRNA水平下降，细胞外基质（ECM）蛋白编码基因的表达也降低。因此，静电纺丝纤维支架是一个可调节的平台，用于研究成纤维细胞激活机制及其在纤维化疾病中的作用。
