Risk prediction of kidney function in long-term kidney transplant recipients

Area of Science:

• Nephrology
• Transplant Medicine
• Biomarker Discovery

Background:

• Limited tools exist for predicting kidney function in long-term kidney transplant recipients (KTRs).
• The elabela (ELA), apelin (APLN), and APJ receptor axis plays a role in vascular and cardiac physiology.
• This axis opposes the renin-angiotensin-aldosterone system.

Purpose of the Study:

• To investigate potential serum biomarkers for predicting kidney function in long-term kidney transplant recipients (KTRs).
• To assess the association of serum markers (APLN, ELA, FGF-23, α-Klotho) with graft function and outcomes.
• To evaluate the predictive performance of baseline estimated glomerular filtration rate (eGFR) and serum biomarkers for future graft function.

Main Methods:

• A longitudinal, observational cohort study of 102 KTRs with stable graft function for at least 24 months.
• Serum levels of APLN, ELA, FGF-23, and α-Klotho were measured using enzyme-linked immunoassay.
• Comparison with 32 healthy controls (HCs); statistical analyses included correlation, random forest regression, and Cox proportional hazard models.

Main Results:

• Long-term KTRs showed higher serum FGF-23, ELA, and APLN, but lower α-Klotho compared to HCs.
• Baseline eGFR was a strong predictor of future 2-year eGFR, explaining 87% of the variance.
• Lower α-Klotho and higher FGF-23 were significant predictors of death-censored allograft loss.

Conclusions:

• Serum FGF-23 and α-Klotho are relevant candidate markers for predicting renal allograft outcomes.
• The elabela (ELA) and apelin (APLN) peptides may also be relevant for future predictive studies.
• Baseline eGFR remains a crucial factor in predicting long-term kidney transplant function.