CD4 and Cowden disease: Due to the important role of IL-6 and Tregs in celiac disease and coronavirus infection, and owing to the importance of Treg markers in their development and activity, this study aimed to evaluate the gene expression of IL-6, CD4, CD25, and FOXP3 in peripheral blood samples of newly diagnosed CD patients and COVID-19 infected people, relative to healthy subjects, to compare their inflammation state.