Characterization of bone marrow immune environment in patients with treatment-naive MM. (A-B) Patient characteristics. (A) Time to progression (TTP) for 25 patients with data availability (median, 28 months; range, 0-72 months). (B) Treatment data for patients included in this study. Shown is percentage of patients who received a first-line treatment including an IMiD. (C) Diagram showing sorting strategy. (D) Flow percentages for individual cell populations. Patients are ordered by TTP. (E) Patients with early (TTPlow) and late (TTPhigh) relapse were divided by median TTP. (F) Bar plot showing flow percentages for individual populations comparing TTPlow vs TTPhigh patients. Significance was assessed using an unpaired t test; ∗P ≤ .05. (G) Dot plots showing the distribution of frequencies for individual cell populations shown in panel F. Significance was assessed using an unpaired t test; ∗P ≤ .05. (H) Experimental workflow. Low-input RNA-seq of 100-cell pools was performed using the Smart-Seq2 protocol. (I) Tsne plot showing samples colored by sort marker. (J) Expression of canonical marker genes for individual cell types across immune cell subsets. Tsne, t-distributed stochastic neighbor embedding.