Transforming Growth Factor Beta (TGF-β) in urine is a biomarker of significant interest for assessing pathological processes such as fibrosis, renal function, and systemic disease activity. Urinary TGF-β testing measures levels of this cytokine excreted in urine, offering a non-invasive approach to evaluate its role in cellular signaling and disease mechanisms. This test is mainly utilized in nephrology, cardiology, and oncology to reflect localized and systemic dysregulation of TGF-β-related pathways.
TGF-β in urine primarily originates from renal tissues, which play a central role in maintaining cellular homeostasis and responding to injury. The cytokine regulates extracellular matrix production, cellular differentiation, and immune modulation.
TGF-β is a critical mediator of kidney fibrosis, a common pathway leading to chronic kidney disease (CKD). Elevated urinary TGF-β levels are strongly associated with glomerular and tubular damage, indicating kidney injury even before significant functional decline is detected. Urinary TGF-β is an essential biomarker for identifying patients at risk for CKD progression or complications.
In fibrotic diseases, such as diabetic nephropathy or hypertensive nephrosclerosis, TGF-β drives excessive collagen deposition and matrix remodeling in the kidney. Monitoring urinary TGF-β levels helps evaluate fibrosis severity and the effectiveness of antifibrotic therapies. For patients undergoing treatment with angiotensin-converting enzyme inhibitors (ACEi) or angiotensin receptor blockers (ARBs), urinary TGF-β measurement may provide insights into the therapeutic impact on renal TGF-β signaling pathways.
Beyond nephrology, urinary TGF-β has implications in systemic diseases such as cardiovascular disorders and cancer. TGF-β signaling is intimately linked with vascular remodeling and endothelial dysfunction, contributing to hypertension and atherosclerosis. Urinary TGF-β may reflect systemic vascular changes, providing a link between kidney function and cardiovascular health. Similarly, elevated urinary TGF-β levels in oncology have been explored as a potential biomarker for bladder cancer and other malignancies, as the cytokine is involved in tumor progression, immune suppression, and extracellular matrix interactions within the tumor microenvironment.
Urinary TGF-β is measured using advanced immunoassays, such as ELISA.