Fig. 4.

(A) Comparison of TREC values derived from WB DNA (filled bars), PBMC DNA (striped bars) and CD4⁺ T cell DNA (white bars) in blood drawn from ten patients with rheumatoid arthritis. The age (yrs) of the patients is given below each. TREC values are those derived from the assay standard curve to give raw data values for comparison. Where there are no bars for individual subsets TREC were not detected in the PCR reaction (or insufficient DNA extracted in the case of the two samples where CD4⁺ samples were tested). Each reaction was performed using 200 ng of DNA. (B) TREC values derived from the PCR reactions were compared in these ten patients plus a further six patients from DNA extracted from PBMC and WB DNA. The values derived are strongly correlated (r = 0.92; p < 0.01).