Fig. 1: The T cell compartment in healthy, benign, and malignant bone marrow.

A Experimental design. Bone marrow aspirates were collected from four healthy adults, eight patients with the precursor states of monoclonal gammopathy of undetermined significance (MGUS) or smoldering multiple myeloma (SMM), and ten patients with active, newly-diagnosed multiple myeloma (MM). T cells were isolated using fluorescence activated cell sorting (FACS), followed by simultaneous, single-cell sequencing of RNA (scRNA-seq) and T cell receptors (scTCR-seq). B Uniform manifold approximation and projection (UMAP) of 16 T cell clusters identified with single-cell RNA sequencing, in bone marrow aspirates from four healthy adults, eight patients with MGUS/SMM, and ten patients with active, newly-diagnosed MM. C Relative distribution of the 16 clusters within the T cell compartment of healthy adults (n = 4), MGUS/SMM (n = 8) and MM (n = 10) patients. Error bars represent mean ± standard error mean (SEM). P values were calculated using the Kruskal–Wallis test, *p = 0.03, 0.04 and 0.02, **p = 0.007 from left to right. Source data are provided as a Source Data file. D Uniform manifold approximation and projection (UMAP) of the distribution of T cell clones in bone marrow T cells from healthy adults, MGUS/SMM and MM patients. E Bar chart showing clonal distribution in grouped healthy adults, MGUS/SMM and MM patients. T cell clones were categorized as small (range, 0–≤ 0.01), medium (range, 0.01–≤ 0.1) and large (range, 0.1–≤ 1) based on the percentage of each clonotype within total T cells. Source data are provided as a Source Data file. F Bar chart showing clonal distribution in individual cases.