Enhanced urinary CXCL10 levels: a key urinary marker for rejection in kidney graft recipients.

back groundKidney transplantation remains the most effective treatment for end-stage renal disease. However, acute rejection after transplantation is a major contributor to mortality and morbidity. This study investigates the role of CXCL10 and its receptor CXCR3 as early, non-invasive predictors of rejection by quantifying their mRNA and protein levels in both blood and urine during the first week post-transplant, addressing the limitations of serum creatinine and biopsy. METHODS AND

resultsThe study included 65 adult kidney transplant recipients, divided into a rejected group (n = 27) and a non-rejected group (n = 38). Blood and urine samples were collected during the first week after transplantation. mRNA and protein levels of CXCL10 and its receptor CXCR3 were quantified using SYBR Green real-time PCR and ELISA, respectively. Urinary CXCL10 transcript (AUC = 0.8, P = 0.0002), CXCL10 protein (AUC = 0.79, P = 0.007) and CXCR3 transcript (AUC = 0.83, P = 0.0001) showed relatively high accuracy for detecting inflammation in KTRs. When comparing rejected versus non-rejected groups, urinary CXCL10 transcript demonstrated reliable diagnostic accuracy (AUC = 0.74, P = 0.02). By contrast, urinary CXCL10 protein had lower diagnostic performance (AUC = 0.58, P = 0.53). CXCR3 transcript and protein levels were higher in rejected compared with non-rejected KTRs in both blood and urine, but these markers did not reliably distinguish between rejected and non-rejected recipients.

conclusionUrinary CXCL10 and CXCR3 markers showed rising transcript and protein levels in kidney transplant recipients, correlating with inflammation and suggesting their potential as noninvasive, early biomarkers to predict rejection within the first week post-transplant. While findings support integrating these markers into graft monitoring, standard thresholds require validation before clinical adoption.