Helary C, Rodriguez-Sanchez B, Vigier S, Giraud Guill M-M
CNRS-UMR 7574, laboratoire chimie de la matière condensée, University Pierre and Marie Curie-Paris 6, école pratique des Hautes-Études, 4, place Jussieu, 75005 Paris, France.
Pathol Biol (Paris). 2012 Feb;60(1):7-14. doi: 10.1016/j.patbio.2011.10.007. Epub 2011 Dec 7.
The goal of this study was to understand whether dense fibrillar collagen matrices, with a hierarchical structure resembling native collagen matrices, could be useful to study collagen receptor function, in a more physiological context. The receptor analysed here was integrin α11β1, already shown to be involved in cell attachment and migration on collagen-coated plastic, and also in contraction of loose fibrillar collagen hydrogels.
Collagen matrices prepared here corresponded to dense fibrillar hydrogels concentrated at 5mg/ml. The behaviour of α11β1 deficient fibroblasts seeded on these concentrated matrices was assessed in terms of adhesion, morphology and migration, then compared to that observed on classical hydrogels at 1mg/ml, corresponding to loose collagen matrices.
Short-term attachment assays showed disturbed interactions between α11β1 deficient cells and collagen matrices in a concentration-dependent manner. Long-term assays revealed reduced cell spreading of alpha 11(-/-) cells on the dense collagen matrices, associated with a disturbed cytoskeleton network. Moreover, anoikis was observed when alpha 11(-/-) cells were seeded on 5mg/ml matrices, and not on looser 1mg/ml matrices. In scratch wound in vitro assays, carried out with cells on 5mg/ml fibrillar collagen matrices, alpha 11(-/-) cells migrated much better than their wild-type counterparts. In contrast, no significant difference was observed between wild and knock-out cells seeded on plastic.
The present study demonstrates the validity of in vivo-like dense fibrillar collagen matrices to evaluate cell receptor functions more significantly than with 2D cell cultures or loose hydrogels.
本研究的目的是了解具有类似于天然胶原基质层次结构的致密纤维状胶原基质，在更接近生理的环境中是否有助于研究胶原受体功能。此处分析的受体是整合素α11β1，已证明其参与细胞在胶原包被塑料上的附着和迁移，以及疏松纤维状胶原水凝胶的收缩。
此处制备的胶原基质对应于浓度为5mg/ml的致密纤维状水凝胶。将α11β1缺陷型成纤维细胞接种在这些浓缩基质上，评估其在黏附、形态和迁移方面的行为，然后与在浓度为1mg/ml的经典水凝胶（对应疏松胶原基质）上观察到的行为进行比较。
短期附着试验显示，α11β1缺陷型细胞与胶原基质之间的相互作用受到干扰，且呈浓度依赖性。长期试验显示，α11（-/-）细胞在致密胶原基质上的细胞铺展减少，伴有细胞骨架网络紊乱。此外，当α11（-/-）细胞接种在5mg/ml的基质上时观察到失巢凋亡，而接种在较疏松的1mg/ml基质上则未观察到。在用5mg/ml纤维状胶原基质上的细胞进行的体外划痕试验中，α11（-/-）细胞的迁移能力比野生型细胞强得多。相比之下，接种在塑料上的野生型和基因敲除型细胞之间未观察到显著差异。
本研究证明，与二维细胞培养或疏松水凝胶相比，类似体内的致密纤维状胶原基质在更显著地评估细胞受体功能方面具有有效性。
