Development of Lateral Flow Assay for the Detection of Tamm Horsfall Protein in Urine

Abstract

Tamm Horsfall Protein (THP) is the most abundant urinary protein with concentrations of 20-200 mg/day and is known to be involved in a myriad of renal pathological processes such as renal stones and inflammation. THP is produced by renal epithelial cells and is the most abundant urinary protein, which tends to aggregate at higher concentrations. Therefore, our study was aimed to facilitate the detection of THP in urine by a rapid, efficient, and optimum detection using a lateral flow assay system. To develop the assay system, THP was isolated and purified from the urine of a healthy individual and used to generate antibodies in a white male New Zealand rabbit. These anti-THP antibodies were purified from the rabbit serum using the Protein-A column and further conjugated with gold nanoparticles. Gold nanoparticles (GNPs) of the size of 21 nm were synthesized by the chemical reduction method. Conjugation of gold nanoparticles and anti-THP antibodies was optimized by varying pH and concentrations. The developed lateral flow assay was tested with purified THP, and its sensitivity was calculated as 1 mg/ml of THP. This lateral flow immunoassay can detect THP in urine and can be beneficial for the detection of a various pathological or physiological phenomenon involving urinary Tamm Horsefall Protein secretions.