CD4 and tuberculosis: The frequency of circulating CD25+FoxP3+CD4+ or CD25+FoxP3+CD4−T cells was assessed in 26 TB cases (10 had a complete data set, 10 had baseline and two weeks, 4 had baseline, two weeks and 2 months, and 2 had baseline and one week data; the last two groups of patients were excluded from the longitudinal analysis because of insufficient numbers) and 20 healthy donors.