CCR2 and tuberculosis: Amongst these, Reactome Pathway Analysis identified enrichment for matrix metalloproteinases (MMPs), such as MMP-1, that has been strongly implicated in pathogenic degradation of the extracellular matrix in TB (9), as well as for beta defensins that exert both antimicrobial functions and also provide a chemotactic gradient for CCR2-expressing cells, including neutrophils (10) (Fig. 1D).