In a study by Halacheva et al. [25] biopsy specimen of arteries of TAO patients were studied with immunohistochemistry for presence of tumor necrosis factor-α (TNF-α) and expression of intercellular adhesion molecule-1 (ICAM-1), VCAM-1, and E-selectin. The gene discussed is ICAM1; the disease is thromboangiitis obliterans.