Levels of T-cell receptor excision rings and B-cell κ-deletion element in healthy individuals in different age groups

In pediatric practice, quantitative determination of T-cell receptor excision circles (TREC) and B-cell κ-deletion element (KREC) is widely used for diagnostics of primary immunodeficiency states. The issue of diagnostic significance of TREC and KREC studies in the adult population has been poorly studied so far. The purpose of this study is to determine the age-related physiological levels and thresholds of TREC and KREC levels in men and women. We studied the level of TREC and KREC in 213 conditionally healthy individuals aged 18 to 82 years. The study included 104 (49.0%) men and 109 (51.0%) women. Peripheral venous blood was collected. TREC and KREC concentrations were determined in men and women. The principle of the method is based on the quantitative determination of the content of TREC and KREC DNA is performed using the process of amplification of TREC and KREC DNA regions using primers and hybridization probes specific to these regions and Taq DNA polymerase, followed by determination of the accumulation of a specific fluorescent signal in real time. The linear range of quantitative determination of the copy number of TREC and KREC determined using the calibrators of the IMMUNO-BIT reagent kit is from 1x103 to 1x107 copies/ml. Statistical calculations were performed using the StatTech v. 4.7.1 program (Russia). There was a difference in the level of TREC between the groups of men and women. An inverse age-related dependence of the level of TREC and KREC on age was established, indicating a decrease in the number of TREC and KREC during life. Conclusions.The results of the study show that the levels of TREC and KREC decrease with age. In different age groups of donors, we obtained reference values of physiological levels of TREC and KREC. Quantitative determination of TREC and KREC levels should be introduced into routine practice, since it is a very informative method for diagnosing diseases and therapeutic monitoring.