Figure 1

Different gating strategies in MM-flow and POEMS-flow. Gating strategies in (A) MM-flow and (B) POEMS-flow in representative cases of POEMS syndrome are shown. In MM-flow, CD38⁺ (brightly positive)/CD138⁺/CD45^−~+ (negative to positive)/CD19⁻/CD56^± PCs are analyzed in a panel of cytoplasmic immunoglobulin (cy-Ig) light chain expression and the light chain-restricted PCs are determined to be monoclonal PCs. In POEMS-flow, CD38 is gated broadly with dim to bright and CD45 is gated narrowly with negative to dim. CD38⁺ (broadly positive)/CD138⁺/CD45⁻(narrowly negative)/CD19⁻/CD56^± PCs are further analyzed in the panel of cy-Ig light chain expression and the light chain-restricted PCs are determined to be monoclonal PCs. In the representative case of POEMS syndrome shown in this figure, monoclonal PCs are not identified by (A) MM-flow; however, (B) POEMS-flow detects monoclonal PCs (CD38⁺/CD138⁺/CD45⁻/CD19⁻/CD56⁻/λ⁺ population indicated by an arrow). (A) The number indicates the percentage of CD38⁺/CD138⁺ cells in single cells, CD45^−~+/CD38⁺/CD138⁺ cells in CD38⁺/CD138⁺ cells, CD19⁻/CD56^± cells in CD45^−~+/CD38⁺/CD138⁺ cells, and the light chain-restricted PCs in CD38⁺/CD138⁺/CD45^−~+/CD19⁻/CD56^± PCs, respectively. (B) The number indicates the percentage of CD38⁺/CD138⁺ cells in single cells, CD45⁻/CD38⁺/CD138⁺ cells in CD38⁺/CD138⁺ cells, CD19⁻/CD56^± cells in CD45⁻/CD38⁺/CD138⁺ cells, and the light chain-restricted PCs in CD38⁺/CD138⁺/CD45^−~+/CD19⁻/CD56^± PCs, respectively. The numbers in the figures represent the percentages per single cell for each cell population. The size of monoclonal PCs identified by (B) POEMS-flow is 0.22% per single cell, and the κ/λ ratio is 0.062.