PD-L1/PD1 and CD155/TIGIT immune-checkpoint pathways are preserved in the VQ myeloma model. BM cells (1 × 10⁶) from control (IgG1-Cre), VQ-D1, and VQ-D2 myeloma mice (>6 passages) were transplanted into sublethally irradiated recipients as described in Figure 3. (A-B) Flow cytometric analysis of CD138, PD-L1, PD-L2, CD155 (A), MHC-I, and MHC-II (B) on BM of VQ-D1 recipients and LN cells of VQ-D2 recipients. Representative density plots are shown. (C-D) Quantification of PD1⁺ and TIGIT⁺ T cells (CD8⁺ and CD4⁺) in BM, spleen (SP), and LN from age-matched control, VQ-D1 (C), and VQ-D2 (D) recipients. (E-F) Quantification of CD8⁺ and CD4⁺ T cells in BM, SP, and LN of control, VQ-D1 (E), and VQ-D2 (F) recipients. *P < .05; **P < .01; ***P < .001.