Expression of cell adhesion complexes in epithelial cells seeded on biomaterial surfaces

Abstract

Abstract:Clinical studies indicate that soft tissue responses around dental implants vary, depending on the material used. It is therefore also possible that there are differences in how epithelial cells attach to various biomaterial surfaces. We studied the adhesion of cultured epithelial cells to five different dental material surfaces and to glass. The efficacy of adhesion was evaluated by using scanning electron microscopy (SEM) and immunofluorescence microscopy (IF) with antibodies to vinculin and ␣ 6 ␤ 4 integrin, two cell surface molecules that are functional in epithelial cell adhesion. Our results indicate that epithelial cells adhere and spread more avidly on metallic surfaces (titanium, Ti 6 Al 4 V titanium alloy, dental gold alloy) than on ceramic surfaces (dental porcelain, aluminum oxide). As revealed by SEM, cells on metallic surfaces had a flattened morphology and formed multicellular islands. On porcelain and aluminum oxide most cells were round and adhesion occurred as single cells. Surface coverage was over twofold on metallic surfaces as compared to ceramic surfaces. IF of cells grown on metallic surfaces revealed vinculin in well-organized focal contacts and ␣ 6 ␤ 4 integrin in punctate patterns typical of prehemidesmosomes. On porcelain and aluminum oxide surfaces the cells were mostly round and showed less wellorganized adhesion complexes. Our results indicate that smooth metallic biomaterial surfaces are optimal for epithelial cell adhesion and spreading. These findings may have clinical implications in the design of transgingival implant structures.

Intraosseous transcutaneous amputation prostheses versus dental implants: A comparison between keratinocyte and gingival epithelial cell adhesion in vitro

“…With pooled human cells, this up-regulation was significant for both focal adhesion and hemidesmosome expression at 4 h, and for matched ovine cells, at all time-points. Raisanen et al showed that focal adhesions develop earlier than hemidesmosomes in epidermal keratinocytes, and this is consistent with the results of our current study (Raisanen et al, 2000). Pendegrass et al demonstrated that hemidesmosome and focal adhesion expression significantly increase over time for immortalised human keratinocytes cultured on titanium alloy (Pendegrass et al, 2008).…”

“…Based on this paper, augmentation strategies to promote earlier epidermal keratinocyte attachment may prove beneficial in developing a seal at the transcutaneous interface. The attachment of the marginal gingiva to a tooth surface is mediated by the thin non-keratinised JE, which attaches to the tooth surface through hemidesmosomes and the IBL ( Bosshardt et al, 2005;Ikeda et al, 2000;Masaoka et al, 2009;Oksonen et al, 2001;Shimono et al, 2003;Shiraiwa et al, 2002). The JE that develops around dental implants contains laminin-332 and is expressed by cells of the oral mucosa (Masaoka et al, 2009).…”

“…The oral mucosa is the site from which the gingival cells for this study were derived. The success of the transcutaneous interface around teeth and dental implants can be attributed to JE, and specifically to the α6β4 integrin component of hemidesmosomes (Masaoka et al, 2009;Oksonen et al, 2001;Shimono et al, 2003) and the laminin-332 component of the IBL (Ikeda et al, 2000;Fukano et al, 2006). The IBL has been shown to contain a 12-fold higher laminin-332 content compared with the rest of the JE (Kinumatsu et al, 2009).…”

“…They have been shown to be safe and reliable, with survival rates of over 90 % at 15 years (Adell et al, 1986;Brånemark et al, 1982;Tillander et al, 2010). Their success relies on osteointegration and t h e attachment of the gingiva to the implant, which occurs through a junctional epithelium (JE) (Raisanen et al, 2000). The epithelial cells form a tight collar around the implant, as they do around teeth, with hemidesmosomes connecting the bordering epithelial cells of the JE, by a basal lamina-like extracellular matrix termed the internal basal lamina (IBL), to the titanium (Fig.…”

Interdigitated aluminium and titanium sensors for assessing epithelial barrier functionality by electric cell-substrate impedance spectroscopy (ECIS)

“…Given the possible higher transport activity combined with an increased cell adhesion, titanium may foster a highly bioactive growth environment compared to gold and aluminium. Several studies proved that titanium results in improved biocompatibility in the sense of growth rate and cell outgrowth compared to gold and aluminium (Niinomi 1999;Räisänen et al 2000).…”