A recent study investigated the special distribution of different macrophage phenotypes in GCA arteries and showed that CD206+MMP-9+ macrophages are located at the site of tissue destruction, whereas FRβ+ macrophages are located in the inner intima of arteries with degrees of intimal hyperplasia, and that this pattern was specific to GCA lesions and not seen in atherosclerotic lesions. Here, MMP9 is linked to temporal arteritis.