VQ myeloma is readily transplantable to syngeneic secondary recipients. (A) Schematic illustration of VQ myeloma transplantation strategy. (B) VQ1 BM cells (8 × 10⁶; VQ-D1-BM), VQ1 splenocytes (20 × 10⁶; VQ-D1-SP), VQ2 BM cells (5 × 10⁶; VQ-D2-BM), or VQ2 LN cells (20 × 10⁶; VQ-D2-LN) were transplanted into individual recipients. SPEP was performed on recipient mice bled at the moribund stage. The brackets show the γ-globulin component of the serum. The donor cells were isolated from BM, spleen (SP), or LN. (C) Kaplan-Meier survival curves of VQ-D1 and VQ-D2 recipient mice, which were transplanted with VQ1 and VQ2 myeloma cells, respectively. Log-rank test was performed. **P < .01. (D) Representative radiographic images and H&E-stained sections of hind-limb bones from moribund VQ-D1 and VQ-D2 recipient mice and age-matched control mice; scale bar, 50 μm. The red arrows indicate the osteolytic lesions. (E) Representative photo of VQ-D1/D2 recipients with hind-limb paralysis. (F) Flow cytometric analysis of B220 and CD138 expression on BM, SP, and LN cells from VQ-D1 and VQ-D2 recipient mice. Representative density plots are shown. (G) Representative images of H&E-stained BM, SP, liver, LN, and kidney sections; scale bar, 40 μm.