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In the bone marrow (BM), memory plasma cells (PCs) survive for long time periods in dedicated microenvironmental survival niches, resting in terms of proliferation. Several cell types, such as eosinophils and reticular stromal cells, have been reported to contribute to the survival niche of memory PCs. However, until now it has not been demonstrated whether the niche is formed by a fixed cellular microenvironment. By intravital microscopy, we provide for the first time evidence that the direct contacts formed between PCs and reticular stromal cells are stable in vivo, and thus the PCs are sessile in their niches. The majority (∼80%) of PCs directly contact reticular stromal cells in a non‐random fashion. The mesenchymal reticular stromal cells in contact with memory PCs are not proliferating. On the other hand, we show here that eosinophils in the vicinity of long‐lived PCs are vigorously proliferating cells and represent …