VTCN1 and Hashimoto thyroiditis: Additionally, B7-H4 mRNA expression in peripheral blood mononuclear cells (PBMCs) was evaluated via RT-PCR.<h4>Results</h4>The immunohistochemical findings revealed a decrease in levels of B7-H4 protein in thyroid tissue of Graves' disease (GD) and Hashimoto's thyroiditis (HT) patients, compared with those of the normal controls.