Used in immunological research to detect and quantify levels of complement fragment 3b receptor (C3bR) in biological samples. Helps study the activation of the complement system, particularly in relation to immune complex clearance, phagocytosis, and host defense mechanisms. Commonly applied in investigating autoimmune diseases such as systemic lupus erythematosus (SLE), where dysregulation of complement receptors plays a role. Also utilized in evaluating immune responses in infectious diseases, transplant rejection, and inflammatory conditions. The kit enables high-throughput analysis in serum, plasma, and cell lysates, supporting both clinical research and drug development efforts targeting complement-mediated pathways.