Integrin expression at the bone/biomaterial interface

Abstract

The aim of this study was to visualize integrin expression by cells in interface tissue in relation to their ligands. Tissue samples were obtained from 25 patients undergoing revision of aseptically loose total joint replacements. Serial sections were immunolabeled for the integrins alpha(2)beta(1), alpha(v)beta(3), alpha(4)beta(1), alpha(L)beta(2) (CD11a), alpha(M)beta(2) (CD11b), and alpha(X)beta(2) (CD11c), and the ligands fibronectin, laminin, vitronectin, intercellular adhesion molecule-1, and vascular adhesion molecule-1. Most cells were found to express alpha(2)beta(1), most macrophages and giant cells expressed CD11b, and the majority of CD11a was found on perivascular T lymphocytes. From the small amount of alpha(4)beta(1) and vascular adhesion molecule-1 expression in the interface tissue and the combination of CD11a, CD11b, and intercellular adhesion molecule-1 expression, it would seem that macrophages use beta(2) integrins to transmigrate.

Plant Products for Innovative Biomaterials in Dentistry

“…Osseointegration is the final goal to pursue, as well as the hallmark of clinical success, allowing long term stability and functionality of the device. Implantation of a biomaterial usually stimulates a foreign body reaction, usually manifested as phagocyte recruitment and the formation of a fibrous capsule in the peri-implant tissue [7,8]. In this condition, titanium is fibrous-integrated and not osseo-integrated, significantly affecting the performance of the implant and causing complications that ultimately may lead to implant loosening [9].…”

An In Vivo Study of the Host Response to Starch‐Based Polymers and Composites Subcutaneously Implanted in Rats

“…[3][4][5][6][7] Key factors in device failure are believed to be the generation of wear particles and the biological response to them in periprosthetic tissues [2,4] as well as the degradation products of biodegradable materials, both resulting in osteolytic reactions. [5,6,8] The presence of activated macrophages [9][10][11][12][13] or foreignbody giant cells, [9,11,13] and the formation of a fibrous capsule [14,15] are tissue-specific responses that have been the focus of investigation in the evaluation of biomedical implants. Additionally, the evaluation of angiogenesis [12,13,16,17] at the implant area has been realised as an important factor with significant influence in the tissue Summary: Implant failure is one of the major concerns in the biomaterials field.…”

Biocompatibilidade e osteointegração de células osteoblásticas em contato com nióbio

“…As características qualitativas e quantitativas do contato inicial e a adesão das células à superfície do material são influenciadas pelas proteínas de adesão, que por sua vez podem ser reguladas pelas propriedades de superfície do material [30,[56][57][58]. O estudo de Anselme [59] descreve eventos de curta duração das forças iônicas, forças de van der Waal, e o papel, a longo prazo, das proteínas da matriz extracelular (MEC) e proteínas do citoesqueleto, que promovem a ação dos fatores de transcrição e expressão de genes específicos em células.…”

“…Embora não tenha sido claramente demonstrada, é provável que a interação de osteoblastos com a superfície do material é mediada por receptores de proteínas de adesão transmembrana, ou seja, as integrinas [57]. Estes receptores são proteínas de sinalização que são conhecidas por mediar a fixação de células a componentes específicos da MEC e os sinais gerados por eles são conhecidos por regular a proliferação e diferenciação celular [60,61].…”

“…Além disso, possui função ativa na transdução dos sinais do meio ambiente para dentro da célula [30,57,62,115]. Para obtermos maiores informações sobre a relação entre a superfície do nióbio e o comportamento celular, se faz relevante a análise da expressão deste gene.…”