RESUMO
Sickle cell disease (SCD) is canonically characterized by reduced red blood cell (RBC) deformability leading to microvascular obstruction and inflammation. While the biophysical properties of sickle RBCs are known to influence SCD vasculopathy, the contribution of poor RBC deformability to endothelial dysfunction has yet to be fully explored. Leveraging interrelated in vitro and in silico approaches, we introduce a new paradigm of SCD vasculopathy in which poorly deformable sickle RBCs directly cause endothelial dysfunction via mechanotransduction, where endothelial cells sense and pathophysiologically respond to aberrant physical forces independently of microvascular obstruction, adhesion, or hemolysis. We demonstrate that perfusion of sickle RBCs or pharmacologically-dehydrated healthy RBCs into small venule-sized "endothelialized" microfluidics leads to pathologic physical interactions with endothelial cells that directly induce inflammatory pathways. Using a combination of computational simulations and large venule-sized endothelialized microfluidics, we observed that perfusion of heterogeneous sickle RBC subpopulations of varying deformability, as well as suspensions of dehydrated normal RBCs admixed with normal RBCs leads to aberrant margination of the less-deformable RBC subpopulations towards the vessel walls, causing localized, increased shear stress. Increased wall stress is dependent on the degree of subpopulation heterogeneity and oxygen tension and leads to inflammatory endothelial gene expression via mechanotransductive pathways. Our multifaceted approach demonstrates that the presence of sickle RBCs with reduced deformability leads directly to pathological physical (i.e., direct collisions and/or compressive forces) and shear-mediated interactions with endothelial cells and induces an inflammatory response, thereby elucidating the ubiquity of vascular dysfunction in SCD.
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A major cause of cancer recurrence following chemotherapy is cancer dormancy escape. Taxane-based chemotherapy is standard of care in breast cancer treatment aimed at killing proliferating cancer cells. Here, we demonstrate that docetaxel injures stromal cells, which release protumor cytokines, IL-6 and granulocyte colony stimulating factor (G-CSF), that in turn invoke dormant cancer outgrowth both in vitro and in vivo. Single-cell transcriptomics shows a reprogramming of awakened cancer cells including several survival cues such as stemness, chemoresistance in a tumor stromal organoid (TSO) model, as well as an altered tumor microenvironment (TME) with augmented protumor immune signaling in a syngeneic mouse breast cancer model. IL-6 plays a role in cancer cell proliferation, whereas G-CSF mediates tumor immunosuppression. Pathways and differential expression analyses confirmed MEK as the key regulatory molecule in cancer cell outgrowth and survival. Antibody targeting of protumor cytokines (IL-6, G-CSF) or inhibition of cytokine signaling via MEK/ERK pathway using selumetinib prior to docetaxel treatment prevented cancer dormancy outgrowth suggesting a novel therapeutic strategy to prevent cancer recurrence.
Assuntos
Interleucina-6 , Neoplasias , Animais , Camundongos , Docetaxel/farmacologia , Taxoides/farmacologia , Taxoides/uso terapêutico , Citocinas , Fator Estimulador de Colônias de Granulócitos , Quinases de Proteína Quinase Ativadas por MitógenoRESUMO
BACKGROUND: Vein graft failure following cardiovascular bypass surgery results in significant patient morbidity and cost to the healthcare system. Vein graft injury can occur during autogenous vein harvest and preparation, as well as after implantation into the arterial system, leading to the development of intimal hyperplasia, vein graft stenosis, and, ultimately, bypass graft failure. Although previous studies have identified maladaptive pathways that occur shortly after implantation, the specific signaling pathways that occur during vein graft preparation are not well defined and may result in a cumulative impact on vein graft failure. We, therefore, aimed to elucidate the response of the vein conduit wall during harvest and following implantation, probing the key maladaptive pathways driving graft failure with the overarching goal of identifying therapeutic targets for biologic intervention to minimize these natural responses to surgical vein graft injury. METHODS: Employing a novel approach to investigating vascular pathologies, we harnessed both single-nuclei RNA-sequencing and spatial transcriptomics analyses to profile the genomic effects of vein grafts after harvest and distension, then compared these findings to vein grafts obtained 24 hours after carotid-carotid vein bypass implantation in a canine model (n=4). RESULTS: Spatial transcriptomic analysis of canine cephalic vein after initial conduit harvest and distention revealed significant enrichment of pathways (P<0.05) involved in the activation of endothelial cells (ECs), fibroblasts, and vascular smooth muscle cells, namely pathways responsible for cellular proliferation and migration and platelet activation across the intimal and medial layers, cytokine signaling within the adventitial layer, and ECM (extracellular matrix) remodeling throughout the vein wall. Subsequent single-nuclei RNA-sequencing analysis supported these findings and further unveiled distinct EC and fibroblast subpopulations with significant upregulation (P<0.05) of markers related to endothelial injury response and cellular activation of ECs, fibroblasts, and vascular smooth muscle cells. Similarly, in vein grafts obtained 24 hours after arterial bypass, there was an increase in myeloid cell, protomyofibroblast, injury response EC, and mesenchymal-transitioning EC subpopulations with a concomitant decrease in homeostatic ECs and fibroblasts. Among these markers were genes previously implicated in vein graft injury, including VCAN, FBN1, and VEGFC, in addition to novel genes of interest, such as GLIS3 and EPHA3. These genes were further noted to be driving the expression of genes implicated in vascular remodeling and graft failure, such as IL-6, TGFBR1, SMAD4, and ADAMTS9. By integrating the spatial transcriptomics and single-nuclei RNA-sequencing data sets, we highlighted the spatial architecture of the vein graft following distension, wherein activated and mesenchymal-transitioning ECs, myeloid cells, and fibroblasts were notably enriched in the intima and media of distended veins. Finally, intercellular communication network analysis unveiled the critical roles of activated ECs, mesenchymal-transitioning ECs, protomyofibroblasts, and vascular smooth muscle cells in upregulating signaling pathways associated with cellular proliferation (MDK [midkine], PDGF [platelet-derived growth factor], VEGF [vascular endothelial growth factor]), transdifferentiation (Notch), migration (ephrin, semaphorin), ECM remodeling (collagen, laminin, fibronectin), and inflammation (thrombospondin), following distension. CONCLUSIONS: Vein conduit harvest and distension elicit a prompt genomic response facilitated by distinct cellular subpopulations heterogeneously distributed throughout the vein wall. This response was found to be further exacerbated following vein graft implantation, resulting in a cascade of maladaptive gene regulatory networks. Together, these results suggest that distension initiates the upregulation of pathological pathways that may ultimately contribute to bypass graft failure and presents potential early targets warranting investigation for targeted therapies. This work highlights the first applications of single-nuclei and spatial transcriptomic analyses to investigate venous pathologies, underscoring the utility of these methodologies and providing a foundation for future investigations.
Assuntos
Análise de Célula Única , Transcriptoma , Animais , Cães , Masculino , Coleta de Tecidos e Órgãos/efeitos adversos , Coleta de Tecidos e Órgãos/métodos , Feminino , Transdução de Sinais , Perfilação da Expressão Gênica/métodosRESUMO
Zika virus (ZIKV) is a mosquito-borne flavivirus that caused an epidemic in the Americas in 2016 and is linked to severe neonatal birth defects, including microcephaly and spontaneous abortion. To better understand the host response to ZIKV infection, we adapted the 10× Genomics Chromium single-cell RNA sequencing (scRNA-seq) assay to simultaneously capture viral RNA and host mRNA. Using this assay, we profiled the antiviral landscape in a population of human monocyte-derived dendritic cells infected with ZIKV at the single-cell level. The bystander cells, which lacked detectable viral RNA, expressed an antiviral state that was enriched for genes coinciding predominantly with a type I interferon (IFN) response. Within the infected cells, viral RNA negatively correlated with type I IFN-dependent and -independent genes (the antiviral module). We modeled the ZIKV-specific antiviral state at the protein level, leveraging experimentally derived protein interaction data. We identified a highly interconnected network between the antiviral module and other host proteins. In this work, we propose a new paradigm for evaluating the antiviral response to a specific virus, combining an unbiased list of genes that highly correlate with viral RNA on a per-cell basis with experimental protein interaction data. IMPORTANCE: Zika virus (ZIKV) remains a public health threat given its potential for re-emergence and the detrimental fetal outcomes associated with infection during pregnancy. Understanding the dynamics between ZIKV and its host is critical to understanding ZIKV pathogenesis. Through ZIKV-inclusive single-cell RNA sequencing (scRNA-seq), we demonstrate on the single-cell level the dynamic interplay between ZIKV and the host: the transcriptional program that restricts viral infection and ZIKV-mediated inhibition of that response. Our ZIKV-inclusive scRNA-seq assay will serve as a useful tool for gaining greater insight into the host response to ZIKV and can be applied more broadly to the flavivirus field.
Assuntos
Células Dendríticas , Análise de Célula Única , Infecção por Zika virus , Zika virus , Humanos , Zika virus/fisiologia , Infecção por Zika virus/virologia , Infecção por Zika virus/imunologia , Células Dendríticas/virologia , Células Dendríticas/imunologia , RNA Viral/metabolismo , RNA Viral/genética , Interferon Tipo I/metabolismo , Interações Hospedeiro-Patógeno , Análise de Sequência de RNARESUMO
The energetic burden of continuously concentrating solutes against gradients along the tubule may render the kidney especially vulnerable to ischaemia. Acute kidney injury (AKI) affects 3% of all hospitalized patients. Here we show that the mitochondrial biogenesis regulator, PGC1α, is a pivotal determinant of renal recovery from injury by regulating nicotinamide adenine dinucleotide (NAD) biosynthesis. Following renal ischaemia, Pgc1α(-/-) (also known as Ppargc1a(-/-)) mice develop local deficiency of the NAD precursor niacinamide (NAM, also known as nicotinamide), marked fat accumulation, and failure to re-establish normal function. Notably, exogenous NAM improves local NAD levels, fat accumulation, and renal function in post-ischaemic Pgc1α(-/-) mice. Inducible tubular transgenic mice (iNephPGC1α) recapitulate the effects of NAM supplementation, including more local NAD and less fat accumulation with better renal function after ischaemia. PGC1α coordinately upregulates the enzymes that synthesize NAD de novo from amino acids whereas PGC1α deficiency or AKI attenuates the de novo pathway. NAM enhances NAD via the enzyme NAMPT and augments production of the fat breakdown product ß-hydroxybutyrate, leading to increased production of prostaglandin PGE2 (ref. 5), a secreted autacoid that maintains renal function. NAM treatment reverses established ischaemic AKI and also prevented AKI in an unrelated toxic model. Inhibition of ß-hydroxybutyrate signalling or prostaglandin production similarly abolishes PGC1α-dependent renoprotection. Given the importance of mitochondrial health in ageing and the function of metabolically active organs, the results implicate NAM and NAD as key effectors for achieving PGC1α-dependent stress resistance.
Assuntos
Injúria Renal Aguda/metabolismo , Rim/metabolismo , NAD/biossíntese , Fatores de Transcrição/metabolismo , Ácido 3-Hidroxibutírico/metabolismo , Injúria Renal Aguda/tratamento farmacológico , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Aminoácidos/metabolismo , Animais , Citocinas/metabolismo , Dinoprostona/biossíntese , Dinoprostona/metabolismo , Humanos , Isquemia/tratamento farmacológico , Isquemia/metabolismo , Rim/efeitos dos fármacos , Rim/fisiologia , Rim/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Niacinamida/deficiência , Niacinamida/farmacologia , Niacinamida/uso terapêutico , Nicotinamida Fosforribosiltransferase/metabolismo , Oxirredução , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Transdução de Sinais/efeitos dos fármacos , Estresse Fisiológico , Fatores de Transcrição/deficiênciaRESUMO
We have developed a personalized vaccine whereby patient derived leukemia cells are fused to autologous dendritic cells, evoking a polyclonal T cell response against shared and neo-antigens. We postulated that the dendritic cell (DC)/AML fusion vaccine would demonstrate synergy with checkpoint blockade by expanding tumor antigen specific lymphocytes that would provide a critical substrate for checkpoint blockade mediated activation. Using an immunocompetent murine leukemia model, we examined the immunologic response and therapeutic efficacy of vaccination in conjunction with checkpoint blockade with respect to leukemia engraftment, disease burden, survival and the induction of tumor specific immunity. Mice treated with checkpoint blockade alone had rapid leukemia progression and demonstrated only a modest extension of survival. Vaccination with DC/AML fusions resulted in the expansion of tumor specific lymphocytes and disease eradication in a subset of animals, while the combination of vaccination and checkpoint blockade induced a fully protective tumor specific immune response in all treated animals. Vaccination followed by checkpoint blockade resulted in upregulation of genes regulating activation and proliferation in memory and effector T cells. Long term survivors exhibited increased T cell clonal diversity and were resistant to subsequent tumor challenge. The combined DC/AML fusion vaccine and checkpoint blockade treatment offers unique synergy inducing the durable activation of leukemia specific immunity, protection from lethal tumor challenge and the selective expansion of tumor reactive clones.
Assuntos
Vacinas Anticâncer , Leucemia Mieloide Aguda , Animais , Antígenos de Neoplasias , Células Dendríticas , Humanos , Leucemia Mieloide Aguda/terapia , Camundongos , Linfócitos T , VacinaçãoRESUMO
In ß-thalassaemia, anaemia results from ineffective erythropoiesis characterized by inhibition of late-stage erythroid differentiation. We earlier used luspatercept and RAP-536 protein traps for certain Smad2/3-pathway ligands to implicate Smad2/3-pathway overactivation in dysregulated erythroid differentiation associated with murine ß-thalassaemia and myelodysplasia. Importantly, luspatercept alleviates anaemia and has been shown to reduce transfusion burden in patients with ß-thalassaemia or myelodysplasia. Here, we investigated the molecular mechanisms underlying luspatercept action and pSmad2/3-mediated inhibition of erythroid differentiation. In murine erythroleukemic (MEL) cells in vitro, ligand-mediated overactivation of the Smad2/3 pathway reduced nuclear levels of GATA-1 (GATA-binding factor-1) and its transcriptional activator TIF1γ (transcription intermediary factor 1γ), increased levels of reactive oxygen species, reduced cell viability and haemoglobin levels, and inhibited erythroid differentiation. Co-treatment with luspatercept in MEL cells partially or completely restored each of these. In ß-thalassaemic mice, RAP-536 up-regulated Gata1 and its target gene signature in erythroid precursors determined by transcriptional profiling and gene set enrichment analysis, restored nuclear levels of GATA-1 in erythroid precursors, and nuclear distribution of TIF1γ in erythroblasts. Bone marrow cells from ß-thalassaemic mice treated with luspatercept also exhibited restored nuclear availability of GATA-1 ex vivo. Our results implicate GATA-1, and likely TIF1γ, as key mediators of luspatercept/RAP-536 action in alleviating ineffective erythropoiesis.
Assuntos
Receptores de Activinas Tipo II/farmacologia , Diferenciação Celular , Células Eritroides/patologia , Fator de Transcrição GATA1/metabolismo , Fragmentos Fc das Imunoglobulinas/farmacologia , Proteínas Recombinantes de Fusão/farmacologia , Transdução de Sinais , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo , Talassemia beta/patologia , Anemia/complicações , Anemia/tratamento farmacológico , Animais , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Eritroblastos , Células Eritroides/efeitos dos fármacos , Hemoglobinas/metabolismo , Leucemia Eritroblástica Aguda/patologia , Ligantes , Camundongos Endogâmicos C57BL , Fosforilação/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Fatores de Transcrição/metabolismo , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética , Talassemia beta/complicações , Talassemia beta/genéticaRESUMO
Colon cancer recurrence after therapy, such as 5-fluorouracil (5-FU), remains a challenge in the clinical setting. Chemotherapy reduces tumor burden by inducing cell death; however, the resulting dead tumor cells, or debris, may paradoxically stimulate angiogenesis, inflammation, and tumor growth. Here, we demonstrate that 5-FU-generated colon carcinoma debris stimulates the growth of a subthreshold inoculum of living tumor cells in subcutaneous and orthotopic models. Debris triggered the release of osteopontin (OPN) by tumor cells and host macrophages. Both coinjection of debris and systemic treatment with 5-FU increased plasma OPN levels in tumor-bearing mice. RNA expression levels of secreted phosphoprotein 1, the gene that encodes OPN, correlate with poor prognosis in patients with colorectal cancer and are elevated in chemotherapy-treated patients who experience tumor recurrence vs. no recurrence. Pharmacologic and genetic ablation of OPN inhibited debris-stimulated tumor growth. Systemic treatment with a combination of a neutralizing OPN antibody and 5-FU dramatically inhibited tumor growth. These results demonstrate a novel mechanism of tumor progression mediated by OPN released in response to chemotherapy-generated tumor cell debris. Neutralization of debris-stimulated OPN represents a potential therapeutic strategy to overcome the inherent limitation of cytotoxic therapies as a result of the generation of cell debris.-Chang, J., Bhasin, S. S., Bielenberg, D. R., Sukhatme, V. P., Bhasin, M., Huang, S., Kieran, M. W., Panigrahy, D. Chemotherapy-generated cell debris stimulates colon carcinoma tumor growth via osteopontin.
Assuntos
Neoplasias do Colo/patologia , Fluoruracila/farmacologia , Neovascularização Patológica/patologia , Osteopontina/metabolismo , Animais , Antimetabólitos Antineoplásicos/farmacologia , Apoptose , Proliferação de Células , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Camundongos , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Prognóstico , Taxa de Sobrevida , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Multiple myeloma (MM) is characterized by a highly unstable genome, with aneuploidy observed in nearly all patients. The mechanism causing this karyotypic instability is largely unknown, but recent observations have correlated these abnormalities with dysfunctional DNA damage response. Here, we show that the NAD(+)-dependent deacetylase SIRT6 is highly expressed in MM cells, as an adaptive response to genomic stability, and that high SIRT6 levels are associated with adverse prognosis. Mechanistically, SIRT6 interacts with the transcription factor ELK1 and with the ERK signaling-related gene. By binding to their promoters and deacetylating H3K9 at these sites, SIRT6 downregulates the expression of mitogen-activated protein kinase (MAPK) pathway genes, MAPK signaling, and proliferation. In addition, inactivation of ERK2/p90RSK signaling triggered by high SIRT6 levels increases DNA repair via Chk1 and confers resistance to DNA damage. Using genetic and biochemical studies in vitro and in human MM xenograft models, we show that SIRT6 depletion both enhances proliferation and confers sensitization to DNA-damaging agents. Our findings therefore provide insights into the functional interplay between SIRT6 and DNA repair mechanisms, with implications for both tumorigenesis and the treatment of MM.
Assuntos
Dano ao DNA , Mieloma Múltiplo/enzimologia , Mieloma Múltiplo/patologia , Sirtuínas/metabolismo , Acetilação , Linhagem Celular Tumoral , Proliferação de Células , Reparo do DNA , Doxorrubicina/farmacologia , Histonas/metabolismo , Humanos , Lisina/metabolismo , Sistema de Sinalização das MAP Quinases , Modelos Biológicos , Mutagênicos/toxicidade , Prognóstico , Proteínas Elk-1 do Domínio ets/metabolismoRESUMO
OBJECTIVE: Chronic migraine (CM) is often associated with chronic tenderness of pericranial muscles. A distinct increase in muscle tenderness prior to onset of occipital headache that eventually progresses into a full-blown migraine attack is common. This experience raises the possibility that some CM attacks originate outside the cranium. The objective of this study was to determine whether there are extracranial pathophysiologies in these headaches. METHODS: We biopsied and measured the expression of gene transcripts (mRNA) encoding proteins that play roles in immune and inflammatory responses in affected (ie, where the head hurts) calvarial periosteum of (1) patients whose CMs are associated with muscle tenderness and (2) patients with no history of headache. RESULTS: Expression of proinflammatory genes (eg, CCL8, TLR2) in the calvarial periosteum significantly increased in CM patients attesting to muscle tenderness, whereas expression of genes that suppress inflammation and immune cell differentiation (eg, IL10RA, CSF1R) decreased. INTERPRETATION: Because the upregulated genes were linked to activation of white blood cells, production of cytokines, and inhibition of NF-κB, and the downregulated genes were linked to prevention of macrophage activation and cell lysis, we suggest that the molecular environment surrounding periosteal pain fibers is inflamed and in turn activates trigeminovascular nociceptors that reach the affected periosteum through suture branches of intracranial meningeal nociceptors and/or somatic branches of the occipital nerve. This study provides the first set of evidence for localized extracranial pathophysiology in CM. Ann Neurol 2016;79:1000-1013.
Assuntos
Inflamação/genética , Transtornos de Enxaqueca/genética , Periósteo/metabolismo , Adolescente , Adulto , Idoso , Biomarcadores/metabolismo , Estudos de Casos e Controles , Cefaloridina/farmacologia , Doença Crônica , Jejum , Feminino , Expressão Gênica/efeitos dos fármacos , Perfilação da Expressão Gênica/métodos , Humanos , Isoflurano/farmacologia , Lectinas Tipo C/genética , Levodopa/farmacologia , Masculino , Pessoa de Meia-Idade , Inibidor de NF-kappaB alfa/genética , Receptores Imunológicos/genética , Receptores Tipo II de Interleucina-1/genética , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/genética , Adulto JovemRESUMO
BACKGROUND: RNA interference (RNAi) is a powerful platform utilized to target transcription of specific genes and downregulate the protein product. To achieve effective silencing, RNAi is usually applied to cells or tissue with a transfection reagent to enhance entry into cells. A commonly used control is the same transfection reagent plus a "noncoding RNAi". However, this does not control for the genomic response to the transfection reagent alone or in combination with the noncoding RNAi. These control effects while not directly targeting the gene in question may influence expression of other genes that in turn alter expression of the target. The current study was prompted by our work focused on prevention of vascular bypass graft failure and our experience with gene silencing in human aortic smooth muscle cells (HAoSMCs) where we suspected that off target effects through this mechanism might be substantial. We have used Next Generation Sequencing (NGS) technology and bioinformatics analysis to examine the genomic response of HAoSMCs to the transfection reagent alone (polyethyleneimine (PEI)) or in combination with commercially obtained control small interfering RNA (siRNAs) (Dharmacon and Invitrogen). RESULTS: Compared to untreated cells, global gene expression of HAoSMcs after transfection either with PEI or in combination with control siRNAs displayed significant alterations in gene transcriptome after 24 h. HAoSMCs transfected by PEI alone revealed alterations of 213 genes mainly involved in inflammatory and immune responses. HAoSMCs transfected by PEI complexed with siRNA from either Dharmacon or Invitrogen showed substantial gene variation of 113 and 85 genes respectively. Transfection of cells with only PEI or with PEI and control siRNAs resulted in identification of 20 set of overlapping altered genes. Further, systems biology analysis revealed key master regulators in cells transfected with control siRNAs including the cytokine, Interleukin (IL)-1, transcription factor GATA Binding Protein (GATA)-4 and the methylation enzyme, Enhancer of zeste homolog 2 (EZH-2) a cytokine with an apical role in initiating the inflammatory response. CONCLUSIONS: Significant off-target effects in HAoSMCs transfected with PEI alone or in combination with control siRNAs may lead to misleading conclusions concerning the effectiveness of a targeted siRNA strategy. The lack of structural information about transfection reagents and "non coding" siRNA is a hindrance in the development of siRNA based therapeutics.
Assuntos
Aorta/efeitos dos fármacos , Biologia Computacional , Regulação da Expressão Gênica/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Aorta/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste , Fator de Transcrição GATA4/biossíntese , Regulação da Expressão Gênica/genética , Inativação Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Interleucina-1/biossíntese , Músculo Liso Vascular/metabolismo , Complexo Repressor Polycomb 2/biossíntese , Polietilenoimina/administração & dosagem , RNA Interferente Pequeno/genética , Transfecção/métodosRESUMO
IFNγ signaling in endothelial (EC) and smooth muscle cells (SMC) is a key culprit of pathologic vascular remodeling. The impact of NF-κB inhibitory protein A20 on IFNγ signaling in vascular cells remains unknown. In gain- and loss-of-function studies, A20 inversely regulated expression of IFNγ-induced atherogenic genes in human EC and SMC by modulating STAT1 transcription. In vivo, inadequate A20 expression in A20 heterozygote mice aggravated intimal hyperplasia following partial carotid artery ligation. This outcome uniquely associated with increased levels of Stat1 and super-induction of Ifnγ-dependent genes. Transcriptome analysis of the aortic media from A20 heterozygote versus wild-type mice revealed increased basal Ifnß signaling as the likely cause for higher Stat1 transcription. We confirmed higher basal IFNß levels in A20-silenced human SMC and showed that neutralization or knockdown of IFNß abrogates heightened STAT1 levels in these cells. Upstream of IFNß, A20-silenced EC and SMC demonstrated higher levels of phosphorylated/activated TANK-binding kinase-1 (TBK1), a regulator of IFNß transcription. This suggested that A20 knockdown increased STAT1 transcription by enhancing TBK1 activation and subsequently basal IFNß levels. Altogether, these results uncover A20 as a key physiologic regulator of atherogenic IFNγ/STAT1 signaling. This novel function of A20 added to its ability to inhibit nuclear factor-κB (NF-κB) activation solidifies its promise as an ideal therapeutic candidate for treatment and prevention of vascular diseases. In light of recently discovered A20/TNFAIP3 (TNFα-induced protein 3) single nucleotide polymorphisms that impart lower A20 expression or function, these results also qualify A20 as a reliable clinical biomarker for vascular risk assessment.
Assuntos
Aterosclerose/metabolismo , Cisteína Endopeptidases/fisiologia , Proteínas de Ligação a DNA/metabolismo , Interferon beta/metabolismo , Interferon gama/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Músculo Liso Vascular/metabolismo , Proteínas Nucleares/metabolismo , Animais , Anti-Inflamatórios/química , Aorta/patologia , Movimento Celular , Constrição Patológica/metabolismo , Cisteína Endopeptidases/metabolismo , Humanos , Inflamação , Camundongos , Fosforilação , Polimorfismo de Nucleotídeo Único , RNA Interferente Pequeno/metabolismo , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais , Proteína 3 Induzida por Fator de Necrose Tumoral alfa , Células U937RESUMO
UNLABELLED: Epstein-Barr virus (EBV) attachment to human CD21 on the B-cell surface initiates infection. Whether CD21 is a simple tether or conveys vital information to the cell interior for production of host factors that promote infection of primary B cells is controversial, as the cytoplasmic fragment of CD21 is short, though highly conserved. The ubiquity of CD21 on normal B cells, the diversity of this population, and the well-known resistance of primary B cells to gene transfer technologies have all impeded resolution of this question. To uncover the role(s) of the CD21 cytoplasmic domain during infection initiation, the full-length receptor (CD21=CR), a mutant lacking the entire cytoplasmic tail (CT), and a control vector (NEO) were stably expressed in two pre-B-cell lines that lack endogenous receptor. Genome-wide transcriptional analysis demonstrated that stable CD21 surface expression alone (either CR or CT) produced multiple independent changes in gene expression, though both dramatically decreased class I melanoma-associated antigen (MAGE) family RNAs and upregulated genes associated with B-cell differentiation (e.g., C2TA, HLA-II, IL21R, MIC2, CD48, and PTPRCAP/CD45-associated protein). Temporal analysis spanning 72 h revealed that not only CR- but also CT-expressing lines initiated latency. In spite of this, the number and spectrum of transcripts altered in CR- compared with CT-bearing lines at 1 h after infection further diverged. Differential modulation of immediate early cellular transcripts (e.g., c-Jun and multiple histones), both novel and previously linked to CD21-initiated signaling, as well as distinct results from pathway analyses support a separate role for the cytoplasmic domain in initiation of intracellular signals. IMPORTANCE: Membrane proteins that mediate virus attachment tether virus particles to the cell surface, initiating infection. In addition, upon virus interaction such proteins may transmit signals to the interior of the cell that support subsequent steps in the infection process. Here we show that expression of the Epstein-Barr virus B-cell attachment receptor, CD21, in B cells that lack this receptor results in significant changes in gene expression, both before and rapidly following EBV-CD21 interaction. These changes translate into major signaling pathway alterations that are predicted to support stable infection.
Assuntos
Linfócitos B/fisiologia , Linfócitos B/virologia , Diferenciação Celular , Herpesvirus Humano 4/fisiologia , Interações Hospedeiro-Patógeno , Receptores de Complemento 3d/metabolismo , Ligação Viral , Expressão Gênica , Perfilação da Expressão Gênica , Humanos , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Estrutura Terciária de Proteína , Receptores de Complemento 3d/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transdução de SinaisRESUMO
BACKGROUND: The objective of this study was to discover and to validate novel noninvasive biomarkers that distinguish between benign prostate hyperplasia (BPH) and localized prostate cancer (PCa), thereby helping to solve the diagnostic dilemma confronting clinicians who treat these patients. METHODS: Quantitative iTRAQ LC/LC/MS/MS analysis was used to identify proteins that are differentially expressed in the urine of men with BPH compared with those who have localized PCa. These proteins were validated in 173 urine samples from patients diagnosed with BPH (N = 83) and PCa (N = 90). Multivariate logistic regression analysis was used to identify the predictive biomarkers. RESULTS: Three proteins, ß2M, PGA3, and MUC3 were identified by iTRAQ and validated by immunoblot analyses. Univariate analysis demonstrated significant elevations in urinary ß2M (P < 0.001), PGA3 (P = 0.006), and MUC3 (P = 0.018) levels found in the urine of PCa patients. Multivariate logistic regression analysis revealed AUC values ranging from 0.618 for MUC3 (P = 0.009), 0.625 for PGA3 (P < 0.008), and 0.668 for ß2M (P < 0.001). The combination of all three demonstrated an AUC of 0.710 (95% CI: 0.631 - 0.788, P < 0.001); diagnostic accuracy improved even more when these data were combined with PSA categories (AUC = 0.812, (95% CI: 0.740 - 0.885, P < 0.001). CONCLUSIONS: Urinary ß2M, PGA3, and MUC3, when analyzed alone or when multiplexed with clinically defined categories of PSA, may be clinically useful in noninvasively resolving the dilemma of effectively discriminating between BPH and localized PCa.
Assuntos
Adenocarcinoma/diagnóstico , Biomarcadores Tumorais/urina , Hiperplasia Prostática/diagnóstico , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/urina , Adenocarcinoma/urina , Idoso , Diagnóstico Diferencial , Humanos , Masculino , Pessoa de Meia-Idade , Hiperplasia Prostática/urina , Proteoma/metabolismo , Curva ROCRESUMO
The promise of islet cell transplantation cannot be fully realized in the absence of improvements in engraftment of resilient islets. The marginal mass of islets surviving the serial peritransplant insults may lead to exhaustion and thereby contribute to an unacceptably high rate of intermediate and long-term graft loss. Hence, we have studied the effects of treatment with alpha 1-antitrypsin (AAT) in a syngeneic nonautoimmune islet graft model. A marginal number of syngeneic mouse islets were transplanted into nonautoimmune diabetic hosts and islet function was analyzed in control and AAT treated hosts. In untreated controls, marginal mass islet transplants did not restore euglycemia. Outcomes were dramatically improved by short-term AAT treatment. Transcriptional profiling identified 1,184 differentially expressed transcripts in AAT-treated hosts at 3 d posttransplantation. Systems-biology-based analysis revealed AAT down-regulated regulatory hubs formed by inflammation-related molecules (e.g., TNF-α, NF-κB). The conclusions yielded by the systems-biology analysis were rigorously confirmed by QRT-PCR and immunohistology. These data suggest that short-term AAT treatment of human islet transplant recipients may be worthy of a clinical trial.
Assuntos
Transplante das Ilhotas Pancreáticas/métodos , Ilhotas Pancreáticas/citologia , alfa 1-Antitripsina/metabolismo , Animais , Sobrevivência Celular , Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Tipo 1/terapia , Sistema Imunitário , Inflamação , Insulina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Resultado do TratamentoRESUMO
The impact of CD4+ regulatory T cells (Tregs) on human immunodeficiency virus type 1 (HIV-1) pathogenesis remains incompletely understood. Although it has been shown that Tregs can be infected with HIV-1, the consequences of infection on a per-cell basis are still unknown. In vitro HIV-GFP infected and noninfected Tregs were isolated by flow-based cell-sorting to investigate Treg suppressive capacity and gene expression profiles. Our data show that HIV-1-infected Tregs were significantly less suppressive than noninfected Tregs and demonstrated down-regulation of genes critical to Treg function. This impaired function may have detrimental consequences for the control of generalized immune activation and accelerate HIV disease progression.
Assuntos
Infecções por HIV/imunologia , HIV-1/imunologia , Linfócitos T Reguladores/imunologia , Regulação para Baixo , Citometria de Fluxo , Perfilação da Expressão Gênica , Humanos , Imunidade Celular , Técnicas In Vitro , Linfócitos T Reguladores/fisiologia , Linfócitos T Reguladores/virologiaRESUMO
Introduction: Diabetic foot ulcers (DFUs) are a severe complication among diabetic patients, often leading to amputation or even death. Early detection of infection and ischemia is essential for improving healing outcomes, but current diagnostic methods are invasive, time-consuming, and costly. There is a need for non-invasive, efficient, and affordable solutions in diabetic foot care. Methods: We developed DFUCare, a platform that leverages computer vision and deep learning (DL) algorithms to localize, classify, and analyze DFUs non-invasively. The platform combines CIELAB and YCbCr color space segmentation with a pre-trained YOLOv5s algorithm for wound localization. Additionally, deep-learning models were implemented to classify infection and ischemia in DFUs. The preliminary performance of the platform was tested on wound images acquired using a cell phone. Results: DFUCare achieved an F1-score of 0.80 and a mean Average Precision (mAP) of 0.861 for wound localization. For infection classification, we obtained a binary accuracy of 79.76%, while ischemic classification reached 94.81% on the validation set. The system successfully measured wound size and performed tissue color and textural analysis for a comparative assessment of macroscopic wound features. In clinical testing, DFUCare localized wounds and predicted infected and ischemic with an error rate of less than 10%, underscoring the strong performance of the platform. Discussion: DFUCare presents an innovative approach to wound care, offering a cost-effective, remote, and convenient healthcare solution. By enabling non-invasive and accurate analysis of wounds using mobile devices, this platform has the potential to revolutionize diabetic foot care and improve clinical outcomes through early detection of infection and ischemia.
Assuntos
Aprendizado Profundo , Pé Diabético , Pé Diabético/diagnóstico , Pé Diabético/patologia , Humanos , AlgoritmosRESUMO
The tumor microenvironment (TME) of medulloblastoma (MB) influences progression and therapy response, presenting a promising target for therapeutic advances. Prior single-cell analyses have characterized the cellular components of the TME but lack spatial context. To address this, we performed spatial transcriptomic sequencing on sixteen pediatric MB samples obtained at diagnosis, including two matched diagnosis-relapse pairs. Our analyses revealed inter- and intra-tumoral heterogeneity within the TME, comprised of tumor-associated astrocytes (TAAs), macrophages (TAMs), stromal components, and distinct subpopulations of MB cells at different stages of neuronal differentiation and cell cycle progression. We identified dense regions of quiescent progenitor-like MB cells enriched in patients with high-risk (HR) features and an increase in TAAs, TAMs, and dysregulated vascular endothelium following relapse. Our study presents novel insights into the spatial architecture and cellular landscape of the medulloblastoma TME, highlighting spatial patterns linked to HR features and relapse, which may serve as potential therapeutic targets.
RESUMO
Background: Vein graft failure (VGF) following cardiovascular bypass surgery results in significant patient morbidity and cost to the healthcare system. Vein graft injury can occur during autogenous vein harvest and preparation, as well as after implantation into the arterial system, leading to the development of intimal hyperplasia, vein graft stenosis, and, ultimately, bypass graft failure. While previous studies have identified maladaptive pathways that occur shortly after implantation, the specific signaling pathways that occur during vein graft preparation are not well defined and may result in a cumulative impact on VGF. We, therefore, aimed to elucidate the response of the vein conduit wall during harvest and following implantation, probing the key maladaptive pathways driving graft failure with the overarching goal of identifying therapeutic targets for biologic intervention to minimize these natural responses to surgical vein graft injury. Methods: Employing a novel approach to investigating vascular pathologies, we harnessed both single-nuclei RNA-sequencing (snRNA-seq) and spatial transcriptomics (ST) analyses to profile the genomic effects of vein grafts after harvest and distension, then compared these findings to vein grafts obtained 24 hours after carotid-cartoid vein bypass implantation in a canine model (n=4). Results: Spatial transcriptomic analysis of canine cephalic vein after initial conduit harvest and distention revealed significant enrichment of pathways (P < 0.05) involved in the activation of endothelial cells (ECs), fibroblasts (FBs), and vascular smooth muscle cells (VSMCs), namely pathways responsible for cellular proliferation and migration and platelet activation across the intimal and medial layers, cytokine signaling within the adventitial layer, and extracellular matrix (ECM) remodeling throughout the vein wall. Subsequent snRNA-seq analysis supported these findings and further unveiled distinct EC and FB subpopulations with significant upregulation (P < 0.00001) of markers related to endothelial injury response and cellular activation of ECs, FBs, and VSMCs. Similarly, in vein grafts obtained 24 hours after arterial bypass, there was an increase in myeloid cell, protomyofibroblast, injury-response EC, and mesenchymal-transitioning EC subpopulations with a concomitant decrease in homeostatic ECs and fibroblasts. Among these markers were genes previously implicated in vein graft injury, including VCAN (versican), FBN1 (fibrillin-1), and VEGFC (vascular endothelial growth factor C), in addition to novel genes of interest such as GLIS3 (GLIS family zinc finger 3) and EPHA3 (ephrin-A3). These genes were further noted to be driving the expression of genes implicated in vascular remodeling and graft failure, such as IL-6, TGFBR1, SMAD4, and ADAMTS9. By integrating the ST and snRNA-seq datasets, we highlighted the spatial architecture of the vein graft following distension, wherein activated and mesenchymal-transitioning ECs, myeloid cells, and FBs were notably enriched in the intima and media of distended veins. Lastly, intercellular communication network analysis unveiled the critical roles of activated ECs, mesenchymal transitioning ECs, protomyofibroblasts, and VSMCs in upregulating signaling pathways associated with cellular proliferation (MDK, PDGF, VEGF), transdifferentiation (Notch), migration (ephrin, semaphorin), ECM remodeling (collagen, laminin, fibronectin), and inflammation (thrombospondin), following distension. Conclusions: Vein conduit harvest and distension elicit a prompt genomic response facilitated by distinct cellular subpopulations heterogeneously distributed throughout the vein wall. This response was found to be further exacerbated following vein graft implantation, resulting in a cascade of maladaptive gene regulatory networks. Together, these results suggest that distension initiates the upregulation of pathological pathways that may ultimately contribute to bypass graft failure and presents potential early targets warranting investigation for targeted therapies. This work highlights the first applications of single-nuclei and spatial transcriptomic analyses to investigate venous pathologies, underscoring the utility of these methodologies and providing a foundation for future investigations.