Used in biomedical research to quantify levels of human polyimmunoglobulin receptor (pIgR) in biological samples such as serum, plasma, cell culture supernatants, and mucosal secretions. The kit enables researchers to study pIgR's role in mucosal immunity, particularly its involvement in transporting immunoglobulins like IgA and IgM across epithelial cells. Commonly applied in studies related to inflammatory diseases, infections, autoimmune disorders, and cancer—especially in tissues with mucosal surfaces such as the gut, lungs, and reproductive tract. The assay supports high-throughput analysis and provides a reliable, sensitive method for monitoring changes in pIgR expression under various experimental or clinical conditions.