Interleukin-6 expression by osteoblast-like MG63 cells challenged with four acrylic bone cements

Periprosthetic osteolysis is a major clinical problem in total hip and tota l knee arthroplasty and polymethylmethacrylate (PMMA) is a possible etiolog ic factor. Recently, increasing importance was ascribed to interleukin-6 (I L-6) as an agent favouring bone resorption. The aim of the present study wa s to investigate the role of bone cements on IL-6 production by MG63. The e ffect of four acrylic bone cements (Sulfix-60(R), CMW 1(R), CMW 2(R), and C MW 3(R)) on the protein release and mRNA expression of IL-6 in osteoblast-l ike cell line MG63 was examined using IL-1 beta (0.2 mug ml(-1)) as the pos itive control. The extracts in minimum essential medium (MEM) of the cement s were tested, following l-h and 7-day curing. CMW 1(R) and CMW 2(R) signif icantly increased the IL-6 release into the culture media (p < 0.01). The c ells incubated with Sulfix-60(R) and CMW 3(R) produced no significantly dif ferent levels of IL-6 than the basal production. A positive correlation was found between the concentration of IL-6 and the contents of benzoylperoxid e (p = 0.0003) and barium sulphate (p < 0.0001). MG63 expressed IL-6 mRNA c onstitutively, as demonstrated by the positivity of the negative controls t oo. We conclude that CMW 1(R) and CMW 2(R) increase the production of IL-6 in MG63 cells. The response to Sulfix-60(R) and CMW 3(R) is not significant ly greater than the negative control.