Integrin-mediated interactions with a laminin-presenting substrate modulate biosynthesis and phenotypic expression for cells of the human nucleus pulposus.
Integrin-mediated interactions with a laminin-presenting substrate modulate biosynthesis and phenotypic expression for cells of the human nucleus pulposus.
复制标题
整合素介导的与层粘连蛋白呈递底物的相互作用调节人髓核细胞的生物合成和表型表达。
DOI：
10.22203/ecm.v041a50
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发表时间：
2021-06-24
影响因子：
3.1
通讯作者：
Setton L
中科院分区：
文献类型：
--
作者：
Speer J;Barcellona M;Jing L;Liu B;Lu M;Kelly M;Buchowski J;Zebala L;Luhmann S;Gupta M;Setton L
随着年龄的增长和病理改变，髓核(NP)细胞去分化为成纤维细胞样表型，这一变化导致了椎间盘(IVD)的退化。层粘连蛋白异构体是发育过程中NP细胞外基质的组成部分，但在成年NP组织中基本消失。将人成年NP细胞暴露于聚乙二醇化的层粘连蛋白-111(PEGLM)制成的水凝胶中，可以调节NP细胞的行为，并促进细胞呈现生物合成活性状态，其基因/蛋白表达和形态与幼年NP细胞中观察到的一致。然而，调控这一效应的机制仍不清楚。在本研究中，通过进行整合素阻断研究以及细胞内信号和细胞表型的分析，鉴定了促进成体退行性NP细胞与层粘连蛋白-111相互作用的整合素亚基。结果表明，整合素α3是细胞与层粘连蛋白黏附的主要调节因子，并与整合素结合下游信号分子(ERK1/2和GSK3β)的磷酸化有关。阻断整合素α3的持续作用还包括减少表型标志物的表达，减少生物合成，改变细胞骨架结构。此外，阻断整合素α3和附加的整合素亚基都会引起细胞聚集的变化，但不会改变单个细胞的表型。这些发现揭示了整合素通过整合素α3介导的相互作用在NP细胞感知和改变表型以响应层粘连蛋白培养的过程中是至关重要的，并进一步表明靶向整合素α3具有逆转或减缓NP细胞退行性变化的潜力。
With aging and pathology, cells of the nucleus pulposus (NP) de-differentiate towards a fibroblast-like phenotype, a change that contributes to degeneration of the intervertebral disc (IVD). Laminin isoforms are a component of the NP extracellular matrix during development but largely disappear in the adult NP tissue. Exposing human adult NP cells to hydrogels made from PEGylated-laminin-111 (PEGLM) has been shown to regulate NP cell behaviors and promote cells to assume a biosynthetically active state with gene/protein expression and morphology consistent with those observed in juvenile NP cells. However, the mechanism regulating this effect has remained unknown. In the present study, the integrin subunits that promote adult degenerative NP cell interactions with laminin-111 are identified by performing integrin blocking studies along with assays of intracellular signaling and cell phenotype. The findings indicate that integrin α3 is a primary regulator of cell attachment to laminin and is associated with phosphorylation of signaling molecules downstream of integrin engagement (ERK 1/2 and GSK3β). Sustained effects of blocking integrin α3 were also demonstrated including decreased expression of phenotypic markers, reduced biosynthesis, and altered cytoskeletal organization. Furthermore, blocking both integrin α3 and additional integrin subunits elicited changes in cell clustering, but did not alter the phenotype of single cells. These findings reveal that integrin-mediated interactions through integrin α3 are critical in the process by which NP cells sense and alter phenotype in response to culture upon laminin and further suggest that targeting integrin α3 has potential for reversing or slowing degenerative changes to the NP cell.