Project description:Lymph node (LN) stromal cells, particularly fibroblastic reticular cells (FRCs), provide critical structural support and regulate immunity, tolerance and transport properties of LNs. In many tumors, LN metastasis is predictive of poor prognosis, however, stromal contribution to the evolving microenvironment of tumor draining LNs (TDLN) remains poorly understood. Here we present comparative transcriptional data of resting and TDLN FRCs after different time points of tumor drainage. FRCs were isolated from lymph nodes and FACS sorted based on the expression of CD45-, CD31- and PDPN+
Project description:Fibroblastic reticular cells (FRCs) (CD45- Ter119-MADCAM1- CD21/35- CD31- PDPN-) from skin draining lymph nodes of Grem1-Cre-ERT2.cki; Rosa26-LSL-EYFP mice were sorted and subjected to bulk RNA-seq of Grem1 reporter + and Grem1 reporter - cells.
Project description:The lymph node is home to resident macrophage populations that are essential for healthy immune function and homeostasis. They are involved in multiple processes including the initiation of the local response to pathogens, halting viral and bacterial spread, and clearance of apoptotic cells, but the macrophage niche and factors that create it are largely undefined. Here we analyse fibroblastic reticular cells (FRCs) as an essential component of the lymph node macrophage niche using single-cell RNA-sequencing. Our analysis revealed that most reticular cell subsets within lymph nodes expressed master macrophage regulator CSF1. We further show that signalling through CSF1R was sufficient to support macrophage development, while in the presence of LPS, FRCs underwent a mechanistic switch and maintained support through CSF1R-independent mechanisms. Our data reveal a critically important role for FRCs in the creation of the parenchymal macrophage niche within LNs.
Project description:Secondary lymphoid organs are organized by fibroblastic reticular cells (FRCs), which direct immune cell positioning and support adaptive immunity. However, the mechanisms driving FRC subset differentiation remain unclear. To uncover signaling pathways involved in this process, we performed ATAC-seq on lymph node FRCs lacking Notch2. Our data reveal chromatin remodeling changes in the absence of Notch signaling.
Project description:Secondary lymphoid organs are structurally organized by fibroblastic reticular cells (FRCs), which support immune cell positioning and adaptive immune responses. However, the mechanisms driving the differentiation of FRCs into distinct functional subsets remain unclear. To investigate the role of Notch2 signaling in this process, we performed single-cell RNA sequencing (10x Genomics) on lymph node FRCs lacking Notch2 expression. Our dataset highlights how this pathway contributes to FRC differentiation.
Project description:Secondary lymphoid organs are structurally organized by fibroblastic reticular cells (FRCs), which coordinate immune cell positioning and support adaptive immune responses. However, the mechanisms underlying the differentiation of FRCs into distinct functional subsets remain poorly understood. To investigate the role of Notch2 signaling in this process, we performed single-cell RNA sequencing (10x Genomics) on lymph node immune cells from mice lacking Notch2 expression specifically in FRCs. Our dataset reveals how Notch2 signaling shapes FRC subset differentiation and modulates the composition of neighboring immune cell populations.
Project description:Lymph node is a secondary lymphoid organ that has structural organization related to their immune function, which is highly ordered and compartmentalized. Lymph nodes shelter immune cells and also fibroblastic-like cells such as fibroblastic reticular cells (FRCs). FRCs have mesodermal origin and are classically characterized by the expression of podoplanin (PDPN/gp38) and lack of CD31 expression. FRCs are implicated in several immune processes but the pathways subjacent their function are still a matter of research. Another cell population found in LNs, the double negative cells (DNCs), are even less known. They do not express PDPN or CD31 markers and a specific marker is absent, their localization within the LN is undefined and their phenotype or function, remain to be clarified. Although these cells have been studied in murine models, studies on human FRCs and DNCs are limited and therefore our study should contribute to the understanding of biology and function of these cells and should promote knowledge of efficiency and disorders in the lymph node immune response. This study evaluates gene expression and secretion of cytokines and chemokines in human-derived FRCs and DNCs during homeostasis and following inflammatory stimuli. Our results demonstrate that cytokines and chemokines secreted by human FRCs and DNCs partially differ from those identified in murine models. In addition, our study demonstrates that DNCs expressed a more varied of cytokines when compared with FRCs, while FRCs expressed a wider chemokines pattern. Such differences maybe related with specific functional differences between those cell populations within LNs.
Project description:Fibroblastic reticular cells (FRCs) are heterogeneous. We use single cell RNA sequencing to identify subsets of FRCs in fat-associated lymphoid clusters (FALC) in the mesenteric adipose tissue
