Impact of B cell/lymphoid stromal cell crosstalk in B-cell physiology and malignancy.

Stromal cells have been considered for a long time essentially as a structural component organizing tissue architecture, including those of secondary lymphoid organs. More recently, highly specialized stromal cell subsets were shown to differentially organize immune cell recruitment, survival, and differentiation within lymph nodes. In particular, mature B cells interact with different lymphoid stromal cell networks through bidirectional interactions involving cell-cell contact and soluble factors. Follicular lymphoma (FL) is the paradigm of a B-cell malignancy dependent on a lymphoid-like microenvironment supporting tumor cell growth, drug resistance, and clonal evolution. This review provides an overview of our current knowledge of lymphoid stromal cell heterogeneity and functions in normal B-cell activation. In addition, we also depict the dynamic and plasticity of FL cancer-associated fibroblasts, the mechanisms underlying their key role within FL permissive niches, and their potential as therapeutic targets in this still fatal malignancy.