MMP-2 secretion and gene expression is suppressed by CoMTb. (A), Microglial cells were stimulated with control medium (open bars), CoMCont (diagonal hatched bars), CoMTb (solid bars) or infected with M.tb (grey bars) at an MOI of 1-10. 72 h supernatants were analyzed by Luminex with a representative gelatin zymogram shown. (B), Kinetics of CoM stimulated MMP-2 secretion analyzed by Luminex (representative zymogram shown). (C), MMP-2 gene expression is suppressed by CoMTb. mRNA from microglia stimulated for 24 h was analyzed by RT-PCR, normalized to 18S RNA and expressed as fold change relative to 24 h CoMCont mRNA. The mean ± SD from 3 experiments are shown analyzed by Student's t-test. (D), Astrocyte-microglial signaling networks do not suppress MMP-2 secretion. Conditioned medium from primary human astrocytes was prepared from control (CoACont) and M.tb infected cells (CoATb) and used to stimulate microglia. 72 h cell culture medium MMP-2 secretion was analyzed by Luminex (representative zymogram shown). A, B & D, Bars represent mean values ± SD of 3 samples, representative of at least duplicate experiments performed in triplicate. Data were analyzed by one-way analysis of variance, followed by Tukey's multiple comparison. *p < 0.05, **p < 0.01.