Here we investigated the interaction between macrophages and fibroblasts in GCA-affected arteries and in vitro.<h4>Methods</h4>Immunostaining was performed to detect macrophages (CD68, CD206, FRβ), fibroblasts (CD90, CD200), GM-CSF, M-CSF, IL-6, MMP-3 and tenascin-C in GCA-positive temporal arteries (n = 9) and aorta tissues (n = 9). The gene discussed is CD200; the disease is temporal arteritis.