T cell receptor excision circles as a tool for evaluating thymic function in young children.

Area of Science:

• Immunology
• Pediatrics
• Developmental Biology

Background:

• The thymus is crucial for T cell maturation and immune tolerance, particularly in early life.
• T cell receptor excision circles (TRECs) serve as reliable biomarkers for recent thymic emigrants and thymic function.
• Current understanding of thymic function during infancy is limited, despite its critical role.

Purpose of the Study:

• To evaluate thymic function in healthy children and adolescents using TREC quantification.
• To investigate the relationship between age and thymic function in early development.

Main Methods:

• Analysis of 103 blood samples from individuals aged 3 months to 20 years.
• Quantification of TRECs as a measure of thymic output.
• Statistical analysis to compare TREC levels across different age groups and assess correlations.

Main Results:

• Mean TREC count was 136.77±96.7 copies/μL DNA.
• Significantly higher TREC levels were observed in children aged 0-5 years compared to those aged 10-20 years.
• An inverse correlation between TREC levels and age was identified (r=0.3, P=0.003).

Conclusions:

• Thymic function demonstrably decreases with age, starting from infancy.
• TREC measurement is a valuable tool for assessing thymic function throughout childhood.
• Increased clinical awareness of thymic function in infancy is warranted.