Isotype-based plasma cell subsets display differential niches requirements in the bone marrow

Bone marrow long-lived plasma cells are essential for long-term protection against infection and their persistence within this organ relies on interactions with Cxcl12-expressing stromal cells that are still not clearly identified. Here, using single cell RNAseq and in silico transinteractome analyses we identified LepR+ mesenchymal cells as the stromal cell subset most likely to interact with plasma cells within the bone marrow. Moreover, we demonstrated that depending on the isotype they express, plasma cells may use different set of integrins and adhesion molecules to interact with these stromal cells. Altogether, our results constitute an unprecedented characterization of plasma cell subset stromal niches and open new avenues for the specific targeting of bone marrow plasma cells based on their isotype. Comparative gene expression profiling analysis of single cell RNA-seq data for bone marrow plasma cells of un stimulated mice.