Identification of cynomolgus monkey plasma cell surface phenotype allows cell sorting. (A) Intracellular and cell surface flow cytometry analysis of cynomolgus monkey BM. PCs: CD3⁻CD20⁻ singlets positive for intracellular p63 and IgM (upper panels). Gating strategy to identify BM T and B lineage cells in cynomolgus monkey BM (lower left panel). Flow cytometry graphs depicting CS1 expression on PCs (red), T cells (orange), and B cells (steel blue) from cynomolgus monkey BM (lower middle panel). Forward and side scatter properties of cynomolgus monkey BM PCs (red) backgated onto the singlets (gray, lower right panel). (B) Cell surface flow cytometry analysis of CS1 and CD38 expression on cynomolgus monkey BM PCs (upper panels). Backgating of PCs (red) onto singlets depicting shape, as well as CD27, CS1, and CD138 expression (lower panels). (C) Wright Giemsa staining of a cytospin preparation of flow-sorted cynomolgus monkey PCs from 2 donors. Images taken at original magnification ×100.