APC-Cy7-conjugated anti-mouse primary antibodies are directly labeled immunoreagents that combine a mouse antigen-specific immunoglobulin with the APC-Cy7 tandem fluorochrome. Unlike secondary antibody systems, these primary antibodies bind their target mouse antigen (e.g., CD3, CD4, CD8a, CD44, CD16/CD32) directly, enabling single-step staining for flow cytometric analysis.

APC-Cy7 is a tandem fluorochrome that operates through Förster resonance energy transfer (FRET). It consists of Allophycocyanin (APC) as the energy donor, excited by red laser lines between 595 and 647 nm with an excitation maximum of 651 nm, coupled to the cyanine dye Cy7 as the energy acceptor, which fluoresces at an emission maximum of approximately 779–785 nm. The large Stokes shift moves emission into the near-infrared region, minimizing cellular autofluorescence and spectral overlap with green, orange, and standard far-red fluorophores.

Applications

APC-Cy7-conjugated anti-mouse primary antibodies are validated primarily for flow cytometry, enabling direct immunophenotyping of mouse leukocyte subsets without the need for a secondary reagent. Typical working dilutions for flow cytometry range from 1:50 to 1:100, with suggested use of ≤0.25 µg per 10⁶ cells in 100 µL volume for many products.

Multicolor Panel Design and Compensation

APC-Cy7 occupies a near-infrared detection channel between APC (660 nm) and APC-Cy7 (780 nm). Its spectral similarity to alternatives such as APC-H7, APC-eFluor 780, and APC-Vio770 makes these reagents interchangeable in many panel configurations. APC-Cy7 can be used simultaneously with PE-Cy7 because APC-Cy7 is excited by the 633 nm red laser while PE-Cy7 is excited by the 488 nm blue laser, and their fluorescence is collected in separate detectors. However, PE-Cy7 is slightly excited by the 633 nm laser, so compensation for spillover into the APC-Cy7 channel is required.