Used in immunological research to quantify interleukin-16 levels in biological samples such as serum, plasma, and cell culture supernatants. Enables study of inflammatory responses, immune cell activation, and T-cell recruitment in disease models including asthma, autoimmune disorders, and HIV. Supports biomarker discovery and evaluation of therapeutic interventions by providing a sensitive and specific measurement of IL-16 concentration. Widely applied in preclinical studies and biomedical laboratories focusing on cytokine signaling and immune regulation.