Distinct macrophage phenotypes skewed by local granulocyte macrophage colony‐stimulating factor (GM‐CSF) and macrophage colony‐stimulating factor (M‐CSF) are associated with tissue destruction and intimal hyperplasia in giant cell arteritis

Abstract

Our data document a distinct spatial distribution pattern of CD206⁺/MMP-9⁺ macrophages and FRβ⁺ macrophages in GCA linked to tissue destruction and intimal proliferation, respectively. We suggest that these distinct macrophage phenotypes are skewed by sequential GM-CSF and M-CSF signals. Our study adds to a better understanding of the development and functional role of macrophage phenotypes in the pathogenesis of GCA and opens opportunities for the design of macrophage-targeted therapies.