Anodic oxidation and hydrothermal treatment of commercially pure titanium surfaces increases expression of bone morphogenetic protein‐2 in the adherent macrophage cell line J774A.1

Abstract

The surface property of commercially pure titanium (cpTi) was improved by forming a thin hydroxyapatite (HA) layer by anodic oxidation and hydrothermal treatment (HA/cpTi). We hypothesize that the adhesion of macrophages to HA/cpTi surfaces is important to the process of osseointegration. This study investigates the effect of adhesion of macrophages to HA/cpTi surfaces on the expression of bone morphogenetic protein-2 (BMP-2). The murine macrophage cell line J774A.1 was cultured on HA/cpTi and polished cpTi (S/cpTi). Macrophage cell adhesion was examined by SEM, 0-72 h following plating onto HA/cpTi and S/cpTi. BMP-2 gene expression was examined by RT-PCR analysis. The level of BMP-2 secreted into the supernatant was measured using an ELISA assay. The extent of macrophage adhesion increased with time on both the HA/cpTi and S/cpTi surfaces, with a" higher degree of spreading observed on HA/cpTi than onS/cpTi surfaces after 24 or 72 h. The ratio of BMP-2 mRNA was higher on HA/cpTi than on S/cpTi after 24 h (0.348 vs. 0, p < 0.05) and 72 h (0.584 vs. 0.189, p < 0.05). After 24 h, secretion of BMP-2 was detected in cultures grown on HA/cpTi, but not on S/cpTi. After 72 h, secretion of BMP-2 was detected in cultures grown on S/cpTi, but the levels were higher in cultures grown on HA/cpTi. These findings show that macrophages have the capacity to adhere to HA/cpTi endosseous implants and provide a source of osteoinductive cytokines that may play a key role in the process of osseointegration.

Effects of Titanium Surfaces on the Developmental Profile of Monocytes/Macrophages

“…Thus, it would be reasonable to hypothesize that bio-anodized surfaces induce a Th2 profile. From data obtained in the literature using other cell culture models (7,9), one could infer that the association between surface roughness and the chemical composition of bio-anodized surfaces will induce the release of high amounts of IL10 and TGFβ. However, we do not assume this hypothesis in the present study because the proteins adsorbed by the implant surface may change the way in which the cells adhere onto the biomaterial surface and the way in which the cells are activated (12,14).…”

“…These cells are considered to be key regulators in both the initiation and the resolution of inflammatory responses (1), releasing a large array of products into the extracellular environment, including intermediate reactive oxygen and nitrogen species (3), chemokines (1,4,5), cytokines (5,6), and growth factors (7).…”

TiO2 micro-nano-hybrid surface to alleviate biological aging of UV-photofunctionalized titanium

“…[22][23][24][25] Surface topography alteration affects the expression of osteoinductive growth factors and cytokines in macrophages, which may play an important role in the process of peri-implant osteogenesis. 22 The expression of proinflammatory cytokines possibly modulated by surface topography of titanium substrates may affect the process and maintenance of bone-implant integration.…”

Nano-Scale Topographic Modification of Commercial Pure Titanium Dental Implant to Improve Osseointegration

“…In an attempt to increase the amount and quality of the bone-implant interface, different surface treatments have been explored, such as surface machining, acid etching, electro polishing, anodic oxidation, sandblasting and plasma-spraying. These methods induce chemical modifications associated with alterations in surface topography [4], which have been shown to significantly affect the properties of the surface and subsequently the biologic response that occur at the surface [5].…”