PerCP is a red-emitting fluorescent protein complex isolated from algae, optimally excited by the 488 nm blue laser and detected with a filter centered near 670 nm. However, the most widely used format for anti-pig primary antibodies is the PerCP-Cy5.5 tandem, in which PerCP serves as the donor and Cy5.5 as the acceptor. This tandem is excited by the 488 nm laser and emits in the far-red region around 690–695 nm, a spectral window that is well separated from the green FITC channel (approximately 519 nm) and the orange PE channel (approximately 578 nm), minimizing compensation requirements in complex panels.

Applications

PerCP-conjugated anti-pig primary antibodies are validated primarily for flow cytometry of porcine peripheral blood mononuclear cells, splenocytes, and tissue-derived leukocytes. Documented applications include the identification of CD4⁺ helper T cells using the PerCP-Cy5.5 conjugate of clone 74-12-4, which has been employed alongside FITC-conjugated anti-CD3 (clone PPT3) and PE-conjugated anti-CD8β (clone PG164A) to resolve T cell subsets. The PerCP-Cy5.5 anti-CD3ε conjugate (clone BB23-8E6-8C8) is also widely used in panels combining PE-Cy7-conjugated anti-CD4α (clone 74-12-4) and Alexa Fluor 647-conjugated anti-CD8α (clone 76-2-11). Beyond T cell phenotyping, PerCP-conjugated anti-pig reagents have been applied to intracellular cytokine staining—for example, PerCP-Cy5.5-conjugated anti-IFN-γ (clone P2G10) in porcine PBMC stimulation assays—and to the analysis of monocyte and granulocyte populations using the PerCP-conjugated SWC3a antibody (clone 74-22-15). Certain clones, such as the anti-CD203a antibody (clone PM 18-7), are additionally validated for immunohistochemistry on frozen sections and immunoprecipitation.