Background B7‐H4 is an immunosuppressive molecule extensively studied in tumor diseases and is also of interest in some autoimmune diseases. However, the relationship between B7‐H4 and autoimmune thyroid diseases (AITDs) has not been explored. Objective To investigate the B7‐H4 expression in different tissues of patients with different subtypes of AITDs. Methods The B7‐H4 protein expression in thyroid tissue of the participants was identified through immunohistochemical analyses while concentrations of plasma soluble B7‐H4 (sB7‐H4) were detected by enzyme‐linked immunosorbent assay (ELISA). Additionally, B7‐H4 mRNA expression in peripheral blood mononuclear cells (PBMCs) was evaluated via RT‐PCR. Results 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. Similarly, a decrease was observed in the level of B7‐H4mRNA expression in PBMCs assayed via RT‐PCR. However, based on ELISA results, plasma levels of sB7‐H4 were increased in both GD and HT patients compared to those in normal controls. Conclusion The abnormal expression of B7‐H4 in AITD patients suggests that it may be involved in the onset and progression of the disease. At the same time, the mechanism of action of B7‐H4 in AITD and whether it is a potential therapeutic target need to be further studied.
Wu et al. (Thu,) studied this question.