Regulation and function of extracellular matrix in intestinal epithelial restitution in vitro
Regulation and function of extracellular matrix in intestinal epithelial restitution in vitro
复制标题
DOI：
10.1152/ajpgi.1996.271.5.g729
复制
发表时间：
1996-11-01
影响因子：
4.5
通讯作者：
Podolsky, DK
中科院分区：
文献类型：
--
作者：
Goke, M;Zuk, A;Podolsky, DK
胃肠道上皮损伤的修复最初是通过上皮细胞从伤口边缘迁移（“修复”）来完成的。为了评估上皮损伤后恢复阶段细胞外基质（ECM）的表达和功能，我们利用大鼠肠上皮源性细胞系（IEC-B）的损伤单层进行了体外研究。IEC-6细胞大量表达纤维连接蛋白（FN） mRNA和蛋白，少量表达层粘连蛋白- β (1) （LN β(1)）和LN γ(1)。IV型胶原蛋白（Col IV）表达较弱，未检测到LN α(1)。损伤后，FN、LN β(1)、LN γ(1)和Col IV α (1) mRNA稳态水平显著降低；伤后24 h平均含量降低75 ~ 90%。FN、LN和Col IV蛋白也减少。这些ECM转录本和蛋白质的下调可以通过转化生长因子- β(1)（一种促进恢复的生长因子）来有效地阻止。除了表达变化外，通过免疫荧光检测，损伤后迁移细胞中FN和LN的分布也发生了变化。识别FN上主要细胞附着的Arg-Gly-Asp肽和识别Col IV主要非胶原结构域的抗体抑制细胞迁移，但免疫中和的抗ln抗血清不影响恢复。综上所述，尽管ECM蛋白，特别是FN和Col IV分子在损伤后被矛盾地下调，但它们能够促进肠上皮的修复。
Repair of epithelial injury in the gastrointestinal tract is initially accomplished by migration of epithelial cells from the wound edge (''restitution''). To assess expression and function of the extracellular matrix (ECM) in the restitution phase after epithelial injury, in vitro studies using wounded monolayers of a rat intestinal epithelium-derived cell Line (IEC-B) were undertaken. IEC-6 cells expressed fibronectin (FN) mRNA and protein in large amounts and lesser quantities of laminin-beta(1) (LN beta(1)) and LN gamma(1). Collagen IV (Col IV) was weakly expressed, and LN alpha(1) was not detected. After wounding, a significant decrease in FN, LN beta(1), LN gamma(1), and Col IV alpha(1) mRNA steady-state levels was observed; mean content 24 h after wounding was reduced by 75-90%. FN, LN, and Col IV proteins were also reduced. The downregulation of these ECM transcripts and proteins could be substantially prevented by transforming growth factor-beta(1), a restitution-promoting growth factor. In addition to changes of expression, the distribution of FN and LN was also altered in migrating cells after wounding, as assessed by immunofluorescence. Arg-Gly-Asp peptides that recognize the major cell attachment Bite on FN and antibodies recognizing the main noncollagenous domain of Col IV inhibited cell migration, but immunoneutralizing anti-LN antisera did not affect restitution. In conclusion, although paradoxically downregulated after wounding, ECM proteins, in particular FN and Col IV molecules, are able to enhance intestinal epithelial restitution.