Collected and analyzed for de novo synthesis and activity of MMPs by gelatin zymography. As shown in Figure 1A, pretreatment with TSIIA (0.110 M) significantly attenuated LTA-induced proMMP9 expression and activity. Moreover, pretreatment with TSIIA (10 M) also markedly inhibited LTA (50 g/ml, 16 h)-induced MMP-9 mRNA expression, determined by RT-PCR (Figure 1B), suggesting that AP-1 is an importa