Differential expression of cytokine genes and apoptosis in glioma cell lines upon exposure to bacteria and lipopolysaccharides.

The influences of Escherichia coli, Streptococcus pyogenes and lipopolysaccharides (LPSs) on the expression of cytokines and apoptosis were investigated in two glioma cell lines. IL-1beta and TNF-alpha genes were modulated by bacteria in a time dependent fashion and their expression levels varied from sources of bacteria and cell lines used. E. coli and LPSs induced apoptosis in a very limited cell population as judged by cell counts, membrane alternation and DNA break in situ. The expression of fas and IL-6 genes was not affected by bacterial components. In conclusion, aberrant expression of cytokines but not apoptosis may be the major responses of the cells of glial origin upon exposure to bacteria and their components.