Single-Cell transcriptomes of murine Bone Marrow Stromal Cells Reveal Niche-Associated Heterogeneity

Bone marrow (BM) stromal cells are important in the development and maintenance of cells of the immune system. Using single cell RNA sequencing, we here explore the functional and phenotypic heterogeneity of individual transcriptomes of 1,167 murine BM mesenchymal stromal cells. These cells exhibit a tremendous heterogeneity of gene expression, which precludes the identification of defined subpopulations. However, according to the expression of 108 genes involved in the communication of stromal cells with hematopoietic cells, we have identified 14 non-overlapping subpopulations, with distinct cytokine or chemokine gene expression signatures. With respect to the maintenance of subsets of immune memory cells by stromal cells, we identify distinct subpopulations expressing IL7, IL15 and Tnfsf13b. Together, this study provides a comprehensive dissection of the BM stromal heterogeneity at the single cell transcriptome level and provides a basis to understand their lifestyle and their role as organizers of niches for the long-term maintenance of immune cells. Overall design: For single cell library preparation, ex vivo FACS sorted VCAM-1+CD45-Ter119-CD31- BM cells were applied to the 10X Genomics platform using the Single Cell 3' Reagent Kit V2 (10x Genomics) following the manufacturer's instructions. Upon adapter ligation and index PCR, the quality of the obtained cDNA library was assessed by Qubit quantification, Bioanalyzer fragment analysis (HS DNA Kit, Agilent) and KAPA library quantification qPCR (Roche). The sequencing was performed on a NextSeq500 device (Illumina) using a High Output v2 Kit (150 cycles) with the recommended sequencing conditions (read1: 26nt, read2: 98nt, index1: 8 nt, index2: n.a.).

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Addo RK, Heinrich F, Heinz GA, Schulz D, Sercan-Alp Ö, Lehmann K, Tran CL, Bardua M, Matz M, Löhning M, Hauser AE, Kruglov A, Chang HD, Durek P, Radbruch A, Mashreghi MF