Fatemeh Hajighasemi - Department of Immunology, Faculty of Medicine, Shahed University, Tehran, Iran

Background and Aim : Lypopolysaccharid (LPS) is an endotoxin and major component of outer membrane of gram negative bacteria. Moreover LPS has an important role in inflammation. Matrix metalloproteinases (MMPs) are a large group of enzymes that break down the extracellular matrix result in tissue remodeling and have a main role in inflammation. In this study the effect of LPS on MMP-۲ activity in a monocytic cell line has been assessed in vitro.Methods : Human THP۱ monocytic cells were cultured in complete RPMI medium. Then the cells at the exponential growth phase were incubated with different concentrations of LPS for ۲۴ hours. After that the MMP-۲ activity in the cell culture supernatants was evaluated by gelatin zymography.Results : LPS significantly increased the MMP-۲ activity in the THP۱ monocytic cells dose-dependently compared with untreated control cells in vitro.Conclusion : The results of this study show that LPS up-regulates the MMP-۲ activity in monocytic cells. Therefore it seems that LPS is a potent inducer/enhancer of MMP-۲ activity in monocytic cells. So LPS effect on inflammation may be in part due to its stimulatory effects on MMPs.

Lypopolysaccharid, MMP-۲, monocytes