Used in biomedical research to quantify levels of X-prolyl aminopeptidase 1 (XPNPEP1) in human biological samples such as serum, plasma, and cell culture supernatants. This ELISA kit enables researchers to study the enzyme's role in metabolic pathways involving proline-containing peptides, including the breakdown of bradykinin and other regulatory peptides. It is particularly valuable in studies related to inflammation, cardiovascular function, and neurological disorders where XPNPEP1 activity may be altered. The assay provides a sensitive and specific means to monitor changes in protein expression in clinical and experimental settings, supporting both diagnostic development and therapeutic monitoring.