CD8A and temporal arteritis: Nonetheless, relatively high numbers of infiltrated CD8+ T cells in TAB-positive GCA arteries probably resulted in a significantly lower tissue CD4+:CD8+ T lymphocyte ratio (1.9), compared to TAB-negative GCA (3.3) and non-GCA temporal arteries (5.7), and indicated a more severe disease course in TAB-positive GCA patients (6, 9).