H-DAB staining shows elevated PTX3 level in the orbital adipose-connective tissue from patients with TAO. Positive DAB staining presented in brown color while cell nuclei are blue stained with hematoxylin. ((a) and (b)) Tissue was obtained from patients undergoing plastic surgery and considered as healthy controls. ((c) and (d)) Orbital tissue was from moderate and inactive TAO patients. Magnification is 200x.