Surface phenotype and rapid quantification of blood dendritic cell subsets in the rhesus macaque

BACKGROUND: The study of dendritic cell (DC) biology in the rhesus macaque is becoming increasingly important but is limited by incomplete characterization and the lack of a rapid assay to quantify cells. METHODS: We characterized the surface phenotype of myeloid (mDC) and plasmacytoid DC (pDC) subsets in healthy rhesus macaque blood and developed a flow cytometry-based assay for absolute DC determinations. RESULTS: Rhesus CD11c(+) mDC were CD16(+) CD11b(+) CD56(lo) CD8(-) CD1c(-) whereas CD123(+) pDC lacked expression of these markers. Precise DC determinations were performed using a rapid two-step assay combining the analysis of whole blood and peripheral blood leukocytes (PBL). CONCLUSIONS: Antibodies to CD11b, CD56 and CD16 must be omitted from the lineage antibody cocktail to prevent inadvertent gating-out of DC when analyzing rhesus blood. The combined whole-blood/PBL quantification assay will be invaluable for the rapid and repeated monitoring of blood DC counts in this species.