Grill V, Sandrucci M A, Rizzo R, Narducci P, Bareggi R, Dorigo E
Dipartimento di Morfologia Umana Normale, Università degli Studi, Trieste.
Minerva Stomatol. 2000 Mar;49(3):77-85.
Cell-substratum interactions play a peculiar role in cell proliferation, differentiation and migration. They are regulated by various glycoproteins, among which fibronectin, and by receptors connecting cells to the extracellular matrix, i.e. integrins. Therefore, the aim of this study was to correlate the proliferation rates of the human fibroblast line WI-38 cultured in presence of titanium dental implants to cell adhesion capability to substrata.
WI-38 fibroblasts were cultured in presence of four dental implants in titanium (one hydroxyapatite coated) for 48, 72 and 96 hours. Cell proliferation was evaluated by detecting 5-bromodeoxyuridine incorporation. Fibronectin organization and alpha5beta1 integrin expression were evidenced by indirect immunofluorescence.
A correlation between fibronectin organization and cell proliferation rates was demonstrated: cultures showing fibronectin mainly organized in fibrils presented the highest cell proliferation degrees. After 96 hours, the observed decrease of the number of proliferating cells corresponded to a different fibronectin organization. In presence of the hydroxyapatite coated implant, colocalization of fibronectin and alpha5beta1 integrin was represented in focal contacts in cultures exhibiting the highest proliferation rate, while cells with the lowest proliferation one expressed alpha5beta1 integrin in point contacts.
Evidences obtained in this work showed that both the organization of fibronectin and the expression of alpha5beta1 integrin are strictly correlated to cell proliferation rates. Therefore, these parameters could be useful for evaluating the biocompatibility of dental materials in vitro.
细胞与基质的相互作用在细胞增殖、分化和迁移中发挥着独特作用。它们受多种糖蛋白调控，其中包括纤连蛋白，还受将细胞连接到细胞外基质的受体（即整合素）调控。因此，本研究的目的是将在牙科钛植入物存在下培养的人成纤维细胞系WI - 38的增殖率与细胞对基质的黏附能力相关联。
将WI - 38成纤维细胞在四种钛牙科植入物（一种涂有羟基磷灰石）存在的情况下培养48、72和96小时。通过检测5 - 溴脱氧尿苷掺入来评估细胞增殖。通过间接免疫荧光证实纤连蛋白的组织和α5β1整合素的表达。
证实了纤连蛋白组织与细胞增殖率之间的相关性：显示纤连蛋白主要以纤维形式组织的培养物呈现出最高的细胞增殖程度。96小时后，观察到的增殖细胞数量减少对应于不同的纤连蛋白组织。在涂有羟基磷灰石的植入物存在下，纤连蛋白和α5β1整合素的共定位在增殖率最高的培养物的粘着斑中表现出来，而增殖率最低的细胞在点状接触中表达α5β1整合素。
本研究获得的证据表明，纤连蛋白组织和α5β1整合素的表达均与细胞增殖率密切相关。因此，这些参数可用于体外评估牙科材料的生物相容性。
