CD4 and tuberculosis: In the circulation of TB patients, an increase in FOXP3 mRNA expression was found compared with healthy controls (103), and also an increase in CD4+ T-cell frequencies with regulatory phenotypes was demonstrated [defined as CD4+CD25+/HI (103, 104), CD4+Foxp3+CD25HI (105, 106), or CD4+CD25HICD39+ (105)].