Evaluation of Tamm-Horsfall protein and uroplakin III for forensic identification of urine.

In this study, Tamm-Horsfall protein (THP), a major component of urinary protein, and uroplakin III (UPIII), a transmembrane protein widely regarded as a urothelium-specific marker, were evaluated for forensic identification of urine by ELISA and/or immunohistochemistry. THP was detected in urine, but not in plasma, saliva, semen, vaginal fluid, or sweat by the simple ELISA method developed in this study. In addition, most aged urine stains showed positive results. The urine specificity of THP was confirmed by gene expression analysis. Therefore, as reported previously, ELISA detection of THP can be used as a presumptive test for urine identification. UPIII was specific for immunohistochemical staining of cells in centrifuged precipitate of urine. However, ELISA and RT-PCR for UPIII were not specific for urine. UPIII may be applicable for forensic urine identification by immunohistochemistry.