Figure 2.

CD229 expression on bone marrow-residing primary myeloma cell Bone marrow from patients with MM (N=36) was first screened for CD229 expression by flow cytometry. Viable non-granulocytic cells were gated (A) and myeloma cells were identified by co-expression of CD138⁺/CD38⁺, CD117⁺/CD38⁺, and CD56⁺/CD38⁺. Representative results for CD229 surface expression (open histograms) versus isotype control (black histograms) are shown for nine MM cases (B) and one out of seven MGUS patients included (C). Surface expression of CD229 on bone marrow-residing plasma cells from representative myeloma patients (N=3) and healthy donors (N=3) was analyzed using flow cytometry. Histograms indicate fluorescence of CD138⁺ plasma cells after staining with anti-CD229 antibody (open histograms) or isotype control (gray area) (D).