Treatment with TB-Exo also led to similar results to those of the treatment with TB-CM; there was a decrease in the mRNA levels of MMP-1 and MMP-3, while the expression levels of collagen, elastin, and fibronectin increased significantly in the TB-Exo-treated HNDFs, as compared to in the untreated cells (Figure 3B). Here, MMP3 is linked to tuberculosis.