APC-Cy7 conjugated anti-human primary antibodies are tandem-dye immunoreagents designed for high-parameter flow cytometry. Produced by immunizing hosts such as mouse or goat with human antigens, these antibodies are affinity-purified and conjugated to APC-Cy7, a tandem fluorophore composed of allophycocyanin (APC) covalently linked to the cyanine dye Cy7. The complex utilizes fluorescence resonance energy transfer (FRET): APC excited by a 633 nm red laser transfers energy to Cy7, which emits in the near-infrared region at approximately 780 nm. This far-red emission facilitates multicolor panel design with minimal spectral overlap with FITC, PE, PerCP, and APC. Available specificities include CD markers such as CD3, CD4, CD8, CD19, CD20, CD45, and CD185 (CXCR5). The near-infrared emission can also reduce the contribution of background autofluorescence in human tissue samples.

Applications

APC-Cy7 conjugates are primarily employed in flow cytometry and fluorescence-activated cell sorting (FACS) for the immunophenotyping of human leukocyte subsets in immunology, hematology, and vaccine research. Red laser excitation at 633 nm enables simultaneous detection with fluorophores excited by blue (488 nm) and violet (405 nm) lasers, supporting multicolor panels containing approximately 10 to 18 parameters.

However, APC-Cy7 is susceptible to time- and cell-dependent degradation, also referred to as decoupling, on leukocytes. This process can result in nonspecific signal detection in the APC channel. The effect has been reported to be reduced under conditions involving metabolic inhibition or vitamin C supplementation. For optimal reagent stability, APC-Cy7 conjugates should be stored at 4°C and protected from light. Do not freeze. These products are intended for research use only.