Figure 4: BAL cell expression of inflammatory mediators is increased by ESAT-6. OPN mRNA expression in response to MWCNT was significantly (p ≤ 0.05) doubled by addition of ESAT-6. OPN expression in response to ESAT-6 alone did not differ from sham controls (A). Similarly OPN protein in BAL fluid was significantly (p<0.05) elevated in MWCNT + ESAT-6 compared to MWCNT alone. OPN in ESAT-6 alone was comparable to sham controls (B). BAL cell mRNA expression of the chemokine, CCL2 was elevated (p<0.05) in mice instilled with MWCNT + ESAT-6 compared to mice receiving only MWCNT. There was no difference in CCL2 expression between sham controls and mice receiving only ESAT-6 (C). BAL cell mRNA expression of MMP12 was significantly (p ≤ 0.05) increased in mice instilled with MWCNT + ESAT-6 compared to mice receiving only MWCNT. MMP-12 expression in ESAT-6 alone did not differ from that of sham control (D).