[Production of IL-1 like cytokine by cultured bone cells: inducing effect of Haemophilus actinomycetemcomitans lipopolysaccharide on the cytokine production].

Abstract

We have studies the role that interleukin-1 (IL-1) and IL-1-like cytokine play in the mechanism of bone resorption that occurs in periodontal disease. To determine whether the bone cell itself produces IL-1-like cytokine, we examined bone cells migrating from fragments of newborn mouse calvaria. These bone cells were cultured in alpha-MEM with of without fetal calf serum. IL-1-like cytokine activity was measured by incorporation of [3H] thymidine into C3H/HeJ thymocytes treated with lipopolysaccharide (LPS) from Haemophilus actinomycetemcomitans, a bacterium found in juvenile periodontopathy. The bone cells produced a significant amount of IL-1-like cytokine. The maximum production of IL-1-like cytokine was observed at 24 hours with the LPS in serum-free alpha-MEM. IL-1-like cytokine production stimulated by LPS was marked in the bone cells from LPS high-responder C3H/HeN mice, but not in those from low-responder C3H/HeJ mice. Peak of IL-1-like cytokine activity in culture supernatants of the bone cells was detected in fractions with a molecular weight corresponding to 15,000 daltons.