Used in immunological research to quantify soluble CD86 levels in biological samples such as serum, plasma, or cell culture supernatants. Helps assess immune activation and regulation, particularly in studies related to T-cell co-stimulation, autoimmune diseases, transplant rejection, and cancer immunotherapy. The kit enables high-throughput analysis with high sensitivity and specificity, supporting biomarker discovery and monitoring of therapeutic responses in preclinical and clinical investigations.