Figure 1From: A revised assay for the measurement of T-cell receptor excision circles as a quantitative measure of thymic function in systemic lupus erythematosus(a) Lower axis: serial DNA extractions (see text). Bars represent mean of 10 ± standard deviation. Upper axis: T-cell receptor excision circles (TRECs) per millitre of blood from the same samples (mean ± deviation). (b) TRECs per millitre of whole blood declines with age over a range of ~2 logs from birth.Back to article page