Inflammatory responses to metal oxide ceramic nanopowders

Abstract

Ceramic orthopaedic implants are increasingly popular due to the need for robust total joint replacement implants that have a high success rate long-term and do not induce biological responses in patients. This study was designed to investigate the biological effects of ceramic nanopowders containing aluminium oxide or zirconium oxide to activate the human macrophage THP-1 cell line. In vitro investigation of pro-inflammatory gene expression and chemokine secretion was performed studied using RT-qPCR and ELISA, respectively. TLR4 inhibition, using a small-molecule inhibitor, was used to determine whether ceramic-mediated inflammation occurs in a similar manner to that of metals such as cobalt. THP-1 macrophages were primed with ceramics or LPS and then treated with ATP or ceramics, respectively, to determine whether these nanopowders are involved in the priming or activation of the NLRP3 inflammasome through IL-1β secretion. Cells treated with ceramics significantly increased pro-inflammatory gene expression and protein secretion which was attenuated through TLR4 blockade. Addition of ATP to cells following ceramic treatment significantly increased IL-1β secretion. Therefore, we identify the ability of ceramic metal oxides to cause a pro-inflammatory phenotype in THP-1 macrophages and propose the mechanism by which this occurs is primarily via the TLR4 pathway which contributes to inflammasome signalling.

Advances in Barrier Membranes for Guided Bone Regeneration Techniques

“…In physiological environment, alumina is an inert material matrix, which is non-absorbable and extremely hard. Al 2 O 3 appeared to have no significant cytotoxic effect ( Jamieson et al, 2021 ), however, aluminium is not considered to exhibit osteogenic properties and even recognized for having adverse effects on osteoblasts ( Yang et al, 2018 ). To overcome these limitations, some composites have been developed from two or more materials to obtain the excellent properties of a single material.…”

Pelvic Osteotomies in Children and Adults - Experience of University Medical Centre Ljubljana

“…Also, the type of biomaterial implanted can impact the maturation of dendritic cells which activate the adaptive immune system (Carroll et al, 2016). Metal debris from COI has previously been linked to the development of inflammatory pseudotumours (Jamieson et al, 2021). Pseudotumours are made of soft tissue mass composed of different inflammatory cells such as macrophages and T cells which are localized near the COI (Hart et al, 2012).…”

Zirconia-Toughened Alumina Ceramic Wear Particles Do Not Elicit Inflammatory Responses in Human Macrophages

“…Given the above-mentioned implant-associated inflammatory processes, different prosthetic materials have been tested for toxicity and immunogenicity in numerous in vitro studies by measuring viability and activation of immune cells (peripheral blood mononuclear cells (PBMCs), macrophages, macrophagic cell lines) and pre-osteoblast cells [ 4 , 21 , 22 ]. Macrophages and osteoblasts can phagocyte alumina (Al 2 O 3 ) nanoparticles, which causes activation of an inflammatory response and cytokine release [ 23 , 24 ]. Several studies have shown that Al 2 O 3 particles can activate the immune response; however, there is controversy in the reports about their toxicity and the effect on human cell lines.…”

“…Radziun et al reported that Al 2 O 3 nanoparticles are capable of penetrating the membranes of the L929 mouse fibroblast cell line and the BJ human fibroblast cell line without a significant decrease in cellular viability [ 26 ]. A recent report, however, in which THP-1 macrophages were treated with Al 2 O 3 demonstrated that Al 2 O 3 nanoparticles induced the inflammasome in THP-1 macrophages via activation of the Toll-like receptor 4 (TLR4) pathway [ 23 ]. In that study, 24 h treatment with Al 2 O 3 or zirconia (ZrO 2 ) at the concentration of 50 µm 3 /cell caused upregulation of interleukin 8 ( IL-8 ), CC-chemokine ligand 2 ( CCL2 ), CCL3, and CCL4 expression while not affecting cell viability [ 23 ].…”