C-X-C Motif Chemokine Ligand 10 as a Potential Biomarker of Heart Transplant Rejection: A Comparative Study in Peripheral Blood

BACKGROUND: Heart transplant rejection remains a major posttransplant complication. Endomyocardial biopsy, the diagnostic gold standard, is invasive and costly. This study aimed to evaluate peripheral blood (C-X-C motif chemokine ligand 10 [CXCL10]; IP-10) as a noninvasive molecular biomarker for detecting heart transplant rejection. MATERIALS AND METHODS: This cross-sectional analytical study included three groups: stable heart transplant recipients ( n = 30), patients with confirmed rejection ( n = 30), and healthy controls ( n = 30). After RNA extraction and complementary DNA synthesis, CXCL10 mRNA expression was quantified by the real-time polymerase chain reaction, and relative expression was calculated using the 2 −ΔΔCt method with the control group as the calibrator. CXCL10 positivity was compared across groups using the Chi-square and/or Fisher’s exact tests. RESULTS: CXCL10 positivity differed significantly among the three groups (χ 2 (2) =24.267, P < 0.001). Positivity rates were 80.0% (24/30) in the rejection group, 53.3% (16/30) in the stable group, and 16.7% (5/30) in controls. Relative CXCL10 expression increased 1.8-fold in the rejection group and 1.2-fold in the stable group compared with controls. CONCLUSION: Peripheral blood CXCL10 is associated with heart transplant rejection and may serve as a measurable, noninvasive molecular biomarker for rejection detection and monitoring. Larger, ideally multicenter and longitudinal studies are recommended for validation.