Project description:It has been proposed that bone marrow contributes to the pathogenesis of arteriosclerosis. Nerve growth factor receptor (NGFR) is expressed in bone marrow stromal cells; it is also present in peripheral blood and ischemic coronary arteries. We hypothesized that bone marrow-derived NGFR-positive (NGFR+) cells regulate arterial remodeling. We found that human NGFR+ mononuclear cells (MNCs) in peripheral blood expressed markers for plasmacytoid dendritic cells (DCs) and were susceptible to apoptosis in response to proNGF secreted by activated arterial smooth muscle cells (SMCs). Bone marrow-specific depletion of NGFR+ cells increased neointimal formation following arterial ligation in mice. Bone marrow-derived NGFR+ cells accumulated in the neointima and underwent apoptosis. In contrast, in a bone marrow-specific NGFR-knockout model, SMCs occupied the neointima with augmented proliferation. NGFR+ cells in the neointima promoted mannose receptor C-type 1-positive antiinflammatory macrophage accumulation and secreted antiinflammatory IL-10, thereby inhibiting SMC proliferation in the neointima. In patients with acute coronary syndrome (ACS), NGFR+ peripheral MNCs increased after ACS onset. Multiple linear regression analysis showed that an insufficient increase in NGFR+ peripheral MNCs in ACS was an adjusted independent risk factor for 9-month intimal progression of a nontargeted lesion. Taken together, these observations imply that bone marrow-derived NGFR+ DCs are suppressors of arteriosclerosis.
Project description:The expression of the Nerve growth factor receptor (NGFR) was described in follicular dendritic cells (FDCs), the major lymphoid stromal cell (LSC) compartment regulating B-cell activation within germinal centers (GCs). However, the role of NGFR in humoral response is not well defined. In this work, we have studied the effect of Ngfr KO in LNs organization and function. Ngfr KO led to spontaneous GC formation and expansion of GC B-cell compartment that were related on Ngfr depletion in non-hematopoietic radioresistant compartment. In agreement, Ngfr KO mice showed alterations in LSC with an increased frequency of FDCs harboring an activated phenotype characterized by the overexpression of CD21/35, MAdCAM-1, and VCAM-1. Moreover, Ngfr KO mice showed GC ectopic location, loss of polarization, impaired high-affinity antibody production, and increased circulating autoantibodies. In addition, Ngfr KO/Bcl2 Tg mice displayed increased levels of autoantibodies, higher incidence of autoimmunity, and decreased overall survival. Our work shows that NGFR maintains GC structure and functionality being involved in the regulation of antibody production and immune tolerance.
Project description:Chronic biomechanical stress elicits remodeling of the arterial wall and causes detrimental arterial stenosis and stiffening. In this context, molecular determinants controlling proliferation and stress responses of vascular smooth muscle cells (VSMCs) have been insufficiently studied. We identified the transcription factor ‘nuclear factor of activated T-cells 5’ (NFAT5) as crucial regulatory element of mechanical stress responses of VSMCs. The relevance of this observation for biomechanically induced arterial remodeling was investigated in mice upon SMC-specific knockdown of NFAT5. While blood pressure levels, vascular architecture and flow-induced collateral growth were not affected in these mice, both hypertension-mediated arterial thickening and muscularization of pulmonary arteries during pulmonary artery hypertension (PAH) were impaired. In all models, a decrease in VSMC proliferation was observed indicating that NFAT5 controls activation of VSMCs in the remodeling arterial wall. Mechanistically, mechanoactivation of VSMCs promotes nuclear translocation NFTA5c upon its phosphorylation at Y143 and dephosphorylation at S1197. As evidenced by transcriptome studies, loss of NFAT5 in mechanoactivated VSMCs impairs expression of gene products controlling cell cycle and transcription/translation. These findings identify NFAT5 as molecular determinant of VSMC responses to biomechanical stress and arterial thickening.
Project description:We report the gene expression profiles by NGFR knockdown in H460 and H1299 cell lines and reveal that NGFR ablation activates p53 target gene expression. We examined gene expression in two different non-small-cell lung cancer cell lines, one with wild-type p53 and the other without p53.
Project description:We report the gene expression profiles by NGFR knockdown in H460 and H1299 cell lines and reveal that NGFR ablation activates p53 target gene expression.
Project description:Secreted extracellular vesicles are known to influence the tumor microenvironment and promote metastasis. In this work, we have analyzed the involvement of extracellular vesicles in establishing the lymph node pre-metastatic niche by melanoma cells. We found that small extracellular vesicles (sEVs) derived from highly metastatic melanoma cell lines spread broadly through the lymphatic system and are taken up by lymphatic endothelial cells reinforcing lymph node metastasis. Melanoma-derived sEVs induce lymphangiogenesis, a hallmark of pre-metastatic niche formation, in vitro and in lymphoreporter mice in vivo. Analysis of involved factors demonstrated that the neural growth factor receptor (NGFR) is secreted in melanoma-derived small extracellular vesicles and shuttled to lymphatic endothelial cells inducing lymphangiogenesis and tumor cell adhesion through the activation of ERK and NF-B pathways and ICAM1 expression. Importantly, ablation or inhibition of NGFR in sEVs reversed the lymphangiogenic phenotype, decreased melanoma lymph node metastasis and extended mice survival. Importantly, analysis of NGFR expression in lymph node metastases and matched primary tumors shows that levels of MITF+NGFR+ lymph node metastatic cells are correlated with disease outcome. Our data support that NGFR is secreted in sEVs favoring lymph node pre-metastatic niche formation and lymph node metastasis in melanoma.
Project description:Secreted extracellular vesicles are known to influence the tumor microenvironment and promote metastasis. In this work, we have analyzed the involvement of extracellular vesicles in the establishment of lymph node pre-metastatic niches by melanoma cells. We found that small extracellular vesicles (sEVs) derived from highly metastatic melanoma cell lines spread broadly through the lymphatic system and were taken up by lymphatic endothelial cells, reinforcing lymph node metastasis. Melanoma-derived sEVs induce lymphangiogenesis, a hallmark of pre-metastatic niche formation, in vitro and in lymphoreporter mice in vivo. We found that neural growth factor receptor (NGFR) is secreted in melanoma-derived small extracellular vesicles and shuttled to lymphatic endothelial cells, inducing lymphangiogenesis and tumor cell adhesion through the activation of ERK and NF-B pathways and ICAM1 expression. Importantly, ablation or inhibition of NGFR in sEVs reversed the lymphangiogenic phenotype, decreased melanoma lymph node metastasis and extended the survival. Importantly, analysis of NGFR expression in lymph node metastases and matched primary tumors shows that levels of MITF+NGFR+ lymph node metastatic cells are correlated with disease outcome. Our data support the idea that NGFR secreted in sEVs favors lymph node pre-metastatic niche formation and lymph node metastasis in melanoma