Project description:Blood vascular endothelial cells (BECs) control the immune response by regulating immune cell recruitment, metabolite exchange and blood flow in lymphoid tissues. However, the diversity of BEC and their origins during immune angiogenesis remain poorly understood. Here we profile transcriptomes of BEC from mouse peripheral lymph nodes and map key phenotypes to the vasculature. Our analysis identifies multiple novel subsets including a venous population whose gene signature predicts an unexpectedly selective role in myeloid cell (vs lymphocyte) recruitment to the medulla, confirmed by 2 photon videomicroscopy. We define five phenotypes of capillary lining BEC including a capillary resident regenerative population (CRP) that displays stem cell and migratory gene signatures and contributes to homeostatic BEC turnover and to vascular neogenesis after immunization. Trajectory analyses reveal retention of developmental programs along a progression of cellular phenotypes from CRP to mature venous and arterial BEC subsets. Overall, our single cell atlas provides a molecular blueprint of the lymph node blood vasculature and defines subset specialization for immune cell recruitment and vascular homeostasis.
Project description:Angiogenesis plays a key role in tumor metastasis. Many genes may act in this process including formation of vessels, immune evasion,etc. Different gene expression profiles between lymphoma endothelium cells and reactive lymph node-derived endothelium cells may uncover these genes. And intensive mechanism researches on such key genes may explain the mechanisim of tumor-specific angiogenesis and help to explore effective treatment strategies to prevent/reverse tumor metastasis. We use microarrays to detail gene expression profiles of human lymphoma endothelium and reactive lymph node-derived endothelium. Lymph nodes were taken from surgery samples of cases pathologically diagnosed DLBCL (diffuse large B-cell lymphoma), PTL (peripheral T cell lymphoma) and reactive lymph nodes. The pure endothelium cells were isolated by LCM after immunohistochemical staining of CD34. We found Tim-3 was preferentially expressed on lymphoma-derived ECs via different expression profiles between lymphoma ECs and reactive lymph node-derived ECs. Intensive researches were carried out on Tim-3-expressing -ECs and we found that Tim-3 -expressing-Ecs may play important role on EC-mediated tumor evasion.
Project description:Angiogenesis plays a key role in tumor metastasis. Many genes may act in this process including formation of vessels, immune evasion,etc. Different gene expression profiles between lymphoma endothelium cells and reactive lymph node-derived endothelium cells may uncover these genes. And intensive mechanism researches on such key genes may explain the mechanisim of tumor-specific angiogenesis and help to explore effective treatment strategies to prevent/reverse tumor metastasis. We use microarrays to detail gene expression profiles of human lymphoma endothelium and reactive lymph node-derived endothelium.
Project description:Blood vascular endothelial cells (BECs) control the immune response by regulating blood flow and immune cell recruitment in lymphoid tissues. However, the diversity of BEC and their origins during immune angiogenesis remain unclear. Here we profile transcriptomes of BEC from peripheral lymph nodes and map phenotypes to the vasculature. We identify multiple subsets, including a medullary venous population whose gene signature predicts a selective role in myeloid cell (vs lymphocyte) recruitment to the medulla, confirmed by videomicroscopy. We define five capillary subsets, including a capillary resident precursor (CRP) that displays stem cell and migratory gene signatures, and contributes to homeostatic BEC turnover and to neogenesis of high endothelium after immunization. Cell alignments show retention of developmental programs along trajectories from CRP to mature venous and arterial populations. Our single cell atlas provides a molecular roadmap of the lymph node blood vasculature and defines subset specialization for leukocyte recruitment and vascular homeostasis.
Project description:Metastasis to lymph nodes is an early and prognostically important event in the progression of many human cancers, and is associated with expression of vascular endothelial growth factor-D (VEGF-D). Changes to lymph node vasculature occur during metastasis, and may establish a metastatic niche capable of attracting and supporting tumor cells. We used microarrays to characterise the molecular profiles of endothelial cells from lymph nodes draining metastatic (VEGF-D-overexpressing) and non-metastatic tumors, and to identify differentially-expressed genes that might have therapeutic or prognostic potential. Draining lymph nodes of metastatic (VEGF-D-overexpressing) or non-metastatic tumors were pooled from 1-5 mice and enzymatically digested. Lymph nodes draining metastatic tumors were included for the analysis only if macroscopically enlarged, indicating the presence of metastatic cells. After digestion, tumor cells and leukocytes were depleted via immunomagnetic selection, and the resulting lymph node stromal cells were cultured briefly. Podoplanin was then used as a positive immunomagnetic selection marker to enrich for lymphatic and other endothelial cells in the lymph node. RNA was isolated from biological duplicate lymph node endothelial cell (LN EC) preparations and analysed by microarray.
Project description:In this study we focussed our investigations on ECM remodelling by FRCs during lymph node (LN) expansion, and the interconnection between the cellular and ECM components of the conduit network. We demonstrate a loss of ECM components of the conduit during acute LN expansion
Project description:A classifier was build on 82 training samples to differentiate between lymph node negative (N0) and lymph node metastasis (N+) head and neck squamous-cell carcinomas (HNSCC). The 102 predictor genes that resulted from this classifier where then validated against a independent validation set.
Project description:Despite their key role in immunity our understanding of primary and secondary lymphoid stromal cell heterogeneity and ontogeny remains limited. Here, using genome-wide expression profiling and phenotypic and localization studies, we identify a functionally distinct subset of BP3-PDPN+PDGFRβ+/α+CD34+ stromal adventitial cells in both lymph nodes and thymus that is located within the perivascular niche surrounding PDPN-PDGFRβ+/α-Esam-1+ITGA7+ pericytes. In re-aggregate organ grafts adult CD34+ adventitial cells gave rise to multiple thymic and lymph node mesenchymal subsets including pericytes, FRC-, MRC- and FDC-like cells, the development of which was lymphoid environment dependent. During thymic ontogeny pericytes developed from a transient population of BP3-PDPN+PDGFRβ+/α+CD34-/lo anlage-seeding progenitors that subsequently up-regulated CD34 and we provide evidence suggesting that similar embryonic progenitors give rise to lymph node mesenchymal subsets. These findings extend the current understanding of lymphoid mesenchymal cell heterogeneity and highlight a role of the CD34+ vascular adventitia as a potential ubiquitous source of lymphoid stromal precursors in postnatal tissues. To comprehensively study the differences and similarities between mesenchymal stromal subsets in the thymus and lymph nodes, global gene expression analysis was performed on sorted PDPN-, BP-3-PDPN+ and BP-3+PDPN+ PDGFRb+ lymph node mesenchymal cells (LNMC) as well as PDPN- and BP-3-PDPN+ PDGFRb+ thymic mesenchymal cells (TMC) from 2 w old mice by microarray.