T-cell Receptor Excision Circles in Newborns with Heart Defects

Area of Science:

• Immunology
• Cardiology
• Genetics

Background:

• The cardiac neural crest is crucial for developing the thymus and heart's conotruncus.
• Newborn screening can identify severe T-cell lymphopenia in neonates with congenital heart defects.

Purpose of the Study:

• To investigate T-cell lymphopenia in neonates with heart defects, with or without 22q11.2 deletion syndrome.
• To compare T-cell receptor excision circle (TREC) levels across different congenital heart defect groups.

Main Methods:

• Retrospective cohort study of 125 neonates with heart defects.
• Quantification of TRECs via RT-PCR on newborn screening blood spots.
• Comparison of TREC levels in three groups: non-conotruncal defects, conotruncal defects, and 22q11.2 deletion with conotruncal defects.

Main Results:

• Significantly lower TREC values in neonates with 22q11.2 deletion and conotruncal heart defects compared to other groups (p < 0.001).
• No significant difference in TREC levels between non-syndromic conotruncal and non-conotruncal defects (p = 0.152).
• Low TREC levels correlated with early heart surgery/intervention and fatal outcomes (p = 0.02), and low oxygen saturation (SpO2 < 95%, p = 0.017).

Conclusions:

• Neonates with 22q11.2 deletion syndrome and conotruncal heart defects exhibit significantly reduced TREC levels.
• Low TREC levels may indicate increased risk for severe outcomes in neonates with congenital heart defects.
• Further research is warranted to explore the link between TREC levels, 22q11.2 deletion, and immune function in neonates with congenital heart disease.