Product Description

CD64 (FcγRI) is a high‑affinity IgG Fc receptor mainly expressed on macrophages and monocytes, playing central roles in innate immunity and antibody‑mediated phagocytosis. CD64 functions by binding to the IgG Fc region, activating Syk/PI3K signaling to mediate phagocytosis and cytokine release. Classic functions include opsonophagocytosis of pathogens and cross‑presentation of antigens, bridging innate and adaptive immunity. CD64 expression is upregulated upon inflammatory cytokine stimulation, enhancing effector functions. Dysregulation of CD64 is associated with autoimmune diseases and chronic infections, and it has been used as a biomarker and therapeutic target for antibody drug development, underscoring its critical role in immune defense and therapy.

Screeningbio’s TR-FRET Human CD64 (FcγRI) Binding Assay Kit can be used to screen for IgGs that bind to Human CD64 (FcγRI), and is suitable for functional evaluation of ADCC and ADCP activities of antibody drug candidates. Human CD64 (FcγRI) is hereinafter referred to as CD64. This kit is a competitive immunoassay developed using TR-FRET technology, characterized by simplicity, rapidity, high accuracy, and good reproducibility.

The basic principle of this method is as follows: an anti‑Tag1 antibody conjugated to TR‑FRET Solar Eu*1 specifically recognizes the CD64 protein bearing Tag1. Human IgG conjugated to TR‑FRET LA*2 binds to the CD64 protein, bringing the Solar Eu donor and LA acceptor into close proximity. Upon excitation by an external light source, fluorescence resonance energy transfer occurs between the donor and acceptor. The binding level between CD64 and Human IgG can be determined by measuring the signal intensity at a specific wavelength (665 nm). Free Human IgG or proteins with a human Fc tag in the sample compete with Human IgG‑LA for the binding sites on CD64, and the TR‑FRET signal intensity is inversely proportional to the concentration of free Human IgG or proteins with a human Fc tag in the sample.