Tumor intrinsic GABARAP correlates with tumor immune infiltration in patients with MM. (A-B) Analysis of ICD signature³⁰ (A) and GABARAP (B) expression on data aggregated per a total of 80 patients across MM disease stages (NBM, n = 15; MGUS, n = 19; SMM, n = 10 ; MM, n = 17; RRMM, n = 19).^39-41 (C) Linear regression of GABARAP with ICD signature expression in the same patient cohort. (D) Uniform manifold approximation and projection (UMAP) plots of single-cell transcriptomic of 80 patients with MM showing the density of ICD signature (left) and GABARAP (right) expression on MM plasma cells. (E) Quantification of the expression of selected markers in CD8⁺ T cells significantly differentially expressed between patients with MM with low vs high intratumoral GABARAP expression (median as dichotomizing value). (F) Representative images of hematoxylin and eosin (H&E) and immunohistochemistry (IHC) analysis of GABARAP expression in plasma cells, and CD3 and CD8 staining of T cells from bone marrow biopsies from patients with MM; scale bars, 100 μm. (G) Statistical analysis of the percentage of CD3⁺ or CD8⁺ T cells in 10 patients with negative (neg; n = 5) or positive (pos; n = 5) staining for intratumoral GABARAP. For panels A-B, P values were calculated using the Kruskal-Wallis test. For panel G, ∗P < .05, unpaired Student t test. NBM, normal bone marrow; RRMM, relapsed/refractory MM; SMM, smoldering MM.