scholarly journals RRx-001 Increases Erythrocyte Preferential Adhesion to the Tumor Vasculature

2021 ◽  
Vol 22 (9) ◽  
pp. 4713
Author(s):  
Vinay Jani ◽  
Robert Asaro ◽  
Bryan Oronsky ◽  
Pedro Cabrales
Keyword(s):  
Umbilical Vein ◽  
Fold Increase ◽  
Phase Iii ◽  
Hep G2 ◽  
Hypoxic Conditions ◽  
Tnf Α ◽  
The Difference ◽  
Vascular Adhesion ◽  
Ht 29

Red blood cells (RBCs) serve a variety of functions beyond mere oxygen transport both in health and pathology. Notably, RRx-001, a minimally toxic pleiotropic anticancer agent with macrophage activating and vascular normalization properties currently in Phase III trials, induces modification to RBCs which could promote vascular adhesion similar to sickle cells. This study assessed whether RBCs exposed to RRx-001 adhere to the tumor microvasculature and whether this adhesion alters tumor viability. We next investigated the biomechanics of RBC adhesion in the context of local inflammatory cytokines after treatment with RRx-001 as a potential mechanism for preferential tumor aggregation. Human HEP-G2 and HT-29 tumor cells were subcutaneously implanted into nu/nu mice and were infused with RRx-001-treated and Technetium-99m (99mTc)-labeled blood. RBC adhesion was quantified in an in vitro human umbilical vein endothelial cell (HUVEC) assay under both normoxic and hypoxic conditions with administration of either lipopolysaccharide (LPS) or Tumor necrosis alpha (TNFα) to mimic the known inflammation in the tumor microenvironment. One hour following administration of 99mTc labeled RBCs treated with 10 mg/kg RRx-001, we observed an approximate 2.0-fold and 1.5-fold increase in 99mTc-labeled RBCs compared to vehicle control in HEPG2 and HT-29 tumor models, respectively. Furthermore, we observed an approximate 40% and 36% decrease in HEP-G2 and HT-29 tumor weight, respectively, following treatment with RRx-001. To quantify RBC adhesive potential, we determined τ50, or the shear stress required for 50% disassociation of RBCs from HUVECs. After administration of TNF-α under normoxia, τ50 was determined to be 4.5 dynes/cm2 (95% CI: 4.3–4.7 dynes/cm2) for RBCs treated with 10 μM RRx-001, which was significantly different (p < 0.05) from τ50 in the absence of treatment. Under hypoxic conditions, the difference of τ50 with (4.8 dynes/cm2; 95% CI: 4.6–5.1 dynes/cm2) and without (2.6 dynes/cm2; 95% CI: 2.4–2.8 dynes/cm2) 10 μM RRx-001 treatment was exacerbated (p = 0.05). In conclusion, we demonstrated that RBCs treated with RRx-001 preferentially aggregate in HEP-G2 and HT-29 tumors, likely due to interactions between RRx-001 and cysteine residues within RBCs. Furthermore, RRx-001 treated RBCs demonstrated increased adhesive potential to endothelial cells upon introduction of TNF-α and hypoxia suggesting that RRx-001 may induce preferential adhesion in the tumor but not in other tissues with endothelial dysfunction due to conditions prevalent in older cancer patients such as heart disease or diabetic vasculopathy.

scholarly journals Antioxidant and Hypolipidemic Activity of Açai Fruit Makes It a Valuable Functional Food

Antioxidants ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 40
Author(s):  
Anna Virginia Adriana Pirozzi ◽  
Paola Imbimbo ◽  
Antonella D’Agostino ◽  
Virginia Tirino ◽  
Rosario Finamore ◽  
...  
Keyword(s):  
Functional Food ◽  
Subcutaneous Fat ◽  
Cell Models ◽  
Alcoholic Fatty Liver ◽  
Hypoxic Conditions ◽  
Tnf Α ◽  
Different Types ◽  
Vitro Model ◽  
Alcoholic Fatty Liver Disease

Several plant extracts are acquiring increasing value because of their antioxidant activity and hypolipidemic properties. Among them, great interest has been recently paid to açai fruit as a functional food. The aim of this study was to test the ability of açai extract in reducing oxidative stress and modulating lipid metabolism in vitro using different cell models and different types of stress. In fact, lipid peroxidation as evaluated in a HepG2 model was reduced five-fold when using 0.25 µg/mL of extract, and it was further reduced (20-fold) with the concentration increase up to 2.5 µg/mL. With the non alcoholic fatty liver disease (NAFLD)in vitro model, all concentrations tested showed at least a two-fold reduced fat deposit. In addition, primary adipocytes challenged with TNF-α under hypoxic conditions to mimic the persistent subcutaneous fat, treated with açai extract showed an approximately 40% reduction of fat deposit. Overall, our results show that açai is able to counteract oxidative states in all the cell models analysed and to prevent the accumulation of lipid droplets. No toxic effects and high stability overtime were highlighted at the concentrations tested. Therefore, açai can be considered a suitable support in the prevention of different alterations of lipid and oxidative metabolism responsible for fat deposition and metabolic pathological conditions.

Tetrahydroxystilbene Glucoside Improves TNF-α-Induced Endothelial Dysfunction: Involvement of TGFβ/Smad Pathway and Inhibition of Vimentin Expression

2015 ◽  
Vol 43 (01) ◽  
pp. 183-198 ◽  
Author(s):  
Wenjuan Yao ◽  
Chengjing Gu ◽  
Haoran Shao ◽  
Guoliang Meng ◽  
Huiming Wang ◽  
...  
Keyword(s):  
Endothelial Dysfunction ◽  
Nuclear Translocation ◽  
Cell Damage ◽  
Umbilical Vein ◽  
Polygonum Multiflorum ◽  
Vimentin Expression ◽  
Smad Signaling ◽  
Tnf Α ◽  
Umbilical Vein Endothelial Cells

Endothelial dysfunction plays an important role in the pathogenesis of atherogenesis. 2,3,5,4′-tetrahydroxystilbene-2-O-β-D-glucoside (TSG), an active component of the rhizome extract from Polygonum multiflorum (PM), exhibits significant anti-atherosclerotic activity. Here, we used human umbilical vein endothelial cells (HUVECs) induced by tumor necrosis factor-α (TNF-α) in vitro to investigate the cytoprotective effects of TSG on TNF-α-induced endothelial injury and the related mechanisms. Pretreatment with 50 and 100 μM TSG markedly attenuated TNF-α-induced loss of cell viability and release of lactate dehydrogenase (LDH) and inhibited TNF-α-induced cell apoptosis. The inhibition of vimentin expression was involved in the cytoprotection afforded by TSG. Using inhibitors for PI3K and TGFβ or siRNA for Akt and Smad2, we found that vimentin production in HUVECs is regulated by TGFβ/Smad signaling, but not by PI3K–Akt–mTOR signaling. Meanwhile, TSG inhibited both the expression of TGFβ1 and the phosphorylation of Smad2 and Smad3, and TSG suppressed the nuclear translocation of Smad4 induced by TNF-α. These results suggest that TSG protects HUVECs against TNF-α-induced cell damage by inhibiting vimentin expression via the interruption of the TGFβ/Smad signaling pathway.

Abstract 11: Thioredoxin-Interacting Protein Is Required for VEGF-Induced Angiogenesis Through Regulation of VEGFR2 Internalization

2012 ◽  
Vol 32 (suppl_1) ◽  
Author(s):  
Shin-Young Park ◽  
Chen Yan ◽  
Bradford C Berk
Keyword(s):  
Umbilical Vein ◽  
Fold Increase ◽  
Tube Formation ◽  
In Vivo Studies ◽  
Vegf Receptor ◽  
Cell Fractionation ◽  
Interacting Protein ◽  
Thioredoxin Interacting Protein

Introduction— Thioredoxin-interacting protein (TXNIP) is an arrestin-like scaffold protein. We have shown previously that it is necessary for the transactivation of the vascular endothelial growth factor (VEGF) receptor 2 (VEGFR2) as well as promoting the migration and survival of endothelial cells (ECs). However, its roles in VEGF-induced angiogenesis and in vivo studies of TXNIP function have not been elucidated. Hypothesis— TXNIP regulates VEGF-mediated angiogenesis through modulation of angiogenic signaling pathways in ECs. Methods and Results— To determine the functions of TXNIP in ECs, we generated endothelial-specific TXNIP knockout (EC-TXNIP KO) mice (TXNIPflox/flox: Tie2-Cre/+). These mice displayed impaired capillary growth of the retinal vasculature compared to control mice. Furthermore, aortic rings from EC-TXNIP KO mice exhibited fewer and shorter vascular sprouts than those in control mice. To investigate the role of TXNIP in the regulation of VEGF-induced angiogenesis, we determined the subcellular localization of TXNIP in human umbilical vein EC (HUVEC). Immunofluorescence and cell fractionation studies revealed that upon VEGF stimulation (10ng/ml). TXNIP translocated from cytoplasm to the plasma membrane. There was a 9 fold increase of membrane associated TXNIP with a peak at 15 minutes compared to non-VEGF treatment cells. We hypothesized that membrane associated TXNIP may modulate VEGFR2 internalization and thereby affect VEGF-induced signaling and angiogenesis. To investigate this, we performed in vitro cell surface biotinylation assays in HUVEC. VEGFR2 internalization was decreased by 65% in TXNIP siRNA knockdown cells compared to control siRNA treated cells following VEGF stimulation. Consistent with this result, VEGF-induced phosphorylation of VEGFR2, PLCγ and ERK1/2 was decreased by knockdown of TXNIP. Significantly, TXNIP knockdown inhibited VEGF-induced proliferation and tube formation in vitro. Conclusion— Our results suggest that TXNIP can modulate VEGF-induced angiogenesis and signaling by regulation of VEGFR2 internalization.

scholarly journals Nerolidol Mitigates Colonic Inflammation: An Experimental Study Using both In Vivo and In Vitro Models

Nutrients ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 2032
Author(s):  
Vishnu Raj ◽  
Balaji Venkataraman ◽  
Saeeda Almarzooqi ◽  
Sanjana Chandran ◽  
Shreesh K. Ojha ◽  
...  
Keyword(s):  
Nuclear Translocation ◽  
In Vitro Models ◽  
Mrna Levels ◽  
Colonic Inflammation ◽  
Tnf Α ◽  
Cox 2 ◽  
Anti Inflammatory ◽  
Ht 29

Nerolidol (NED) is a naturally occurring sesquiterpene alcohol present in various plants with potent anti-inflammatory effects. In the current study, we investigated NED as a putative anti-inflammatory compound in an experimental model of colonic inflammation. C57BL/6J male black mice (C57BL/6J) were administered 3% dextran sodium sulfate (DSS) in drinking water for 7 days to induce colitis. Six groups received either vehicle alone or DSS alone or DSS with oral NED (50, 100, and 150 mg/kg body weight/day by oral gavage) or DSS with sulfasalazine. Disease activity index (DAI), colonic histology, and biochemical parameters were measured. TNF-α-treated HT-29 cells were used as in vitro model of colonic inflammation to study NED (25 µM and 50 µM). NED significantly decreased the DAI and reduced the inflammation-associated changes in colon length as well as macroscopic and microscopic architecture of the colon. Changes in tissue Myeloperoxidase (MPO) concentrations, neutrophil and macrophage mRNA expression (CXCL2 and CCL2), and proinflammatory cytokine content (IL-1β, IL-6, and TNF-α) both at the protein and mRNA level were significantly reduced by NED. The increase in content of the proinflammatory enzymes, COX-2 and iNOS induced by DSS were also significantly inhibited by NED along with tissue nitrate levels. NED promoted Nrf2 nuclear translocation dose dependently. NED significantly increased antioxidant enzymes activity (Superoxide dismutase (SOD) and Catalase (CAT)), Hemeoxygenase-1 (HO-1), and SOD3 mRNA levels. NED treatment in TNF-α-challenged HT-29 cells significantly decreased proinflammatory chemokines (CXCL1, IL-8, CCL2) and COX-2 mRNA levels. NED supplementation attenuates colon inflammation through its potent antioxidant and anti-inflammatory activity both in in vivo and in vitro models of colonic inflammation.

scholarly journals Thrombin Stimulation of the Vascular Cell Adhesion Molecule-1 Promoter in Endothelial Cells Is Mediated by Tandem Nuclear Factor-κB and GATA Motifs

2001 ◽  
Vol 276 (50) ◽  
pp. 47632-47641 ◽  
Author(s):  
Takashi Minami ◽  
William C. Aird
Keyword(s):  
Endothelial Cells ◽  
Adhesion Molecule ◽  
Umbilical Vein ◽  
Fold Increase ◽  
Nuclear Factor Κb ◽  
Nuclear Factor ◽  
Mobility Shift ◽  
Response Element ◽  
Vascular Adhesion ◽  
Stimulation Of

The goal of this study was to delineate the transcriptional mechanisms underlying thrombin-mediated induction of vascular adhesion molecule-1 (VCAM-1). Treatment of human umbilical vein endothelial cells with thrombin resulted in a 3.3-fold increase in VCAM-1 promoter activity. The upstream promoter region of VCAM-1 contains a thrombin response element, two nuclear factor κB (NF-κB) motifs, and a tandem GATA motif. In transient transfection assays, mutation of the thrombin response element had no effect on thrombin induction. In contrast, mutation of either NF-κB site resulted in a complete loss of induction, whereas a mutation of the two GATA motifs resulted in a significant reduction in thrombin stimulation. In electrophoretic mobility shift assays, nuclear extracts from thrombin-treated endothelial cells displayed markedly increased binding to the tandem NF-κB and GATA motifs. The NF-κB complex was supershifted with anti-p65 antibodies, but not with antibodies to RelB, c-Rel, p50, or p52. The GATA complex was supershifted with antibodies to GATA-2, but not GATA-3 or GATA-6. A construct containing tandem copies of the VCAM-1 GATA motifs linked to a minimal thymidine kinase promoter was induced 2.4-fold by thrombin. Taken together, these results suggest that thrombin stimulation of VCAM-1 in endothelial cells is mediated by the coordinate action of NF-κB and GATA transcription factors.

Endothelial CSN5 impairs NF-κB activation and monocyte adhesion to endothelial cells and is highly expressed in human atherosclerotic lesions

2013 ◽  
Vol 110 (07) ◽  
pp. 141-152 ◽  
Author(s):  
Yaw Asare ◽  
Erdenechimeg Shagdarsuren ◽  
Johannes Schmid ◽  
Pathricia Tilstam ◽  
Jochen Grommes ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Umbilical Vein ◽  
Negative Regulator ◽  
Multifunctional Protein ◽  
Atherosclerotic Lesions ◽  
Tnf Α ◽  
Reporter Assays ◽  
Umbilical Vein Endothelial Cells

SummaryThe COP9 signalosome (CSN), a multifunctional protein complex involved in the regulation of cullin-RING-E3 ubiquitin ligases (CRLs), has emerged as a regulator of NF-κB signalling. As NF-κB drives the expression of pro-inflammatory and pro-atherosclerotic genes, we probed the yet unknown role of the CSN, in particular CSN5, on NF-KB-mediated atherogenic responses in endothelial cells. Co-immunoprecipitation in human umbilical vein endothelial cells (HUVECs) revealed the presence of a super-complex between IKK and CSN, which dissociates upon TNF-α stimulation. Furthermore, CSN5 silencing enhanced TNF-α-induced IKB-α degradation and NF-κB activity in luci-ferase reporter assays. This was paralleled by an increased NF-KB-driven upregulation of atherogenic chemokines and adhesion molecules, as measured by qPCR and flow cytometry, and translated into an enhanced arrest of THP-1 monocytes on TNF-α-stimulated, CSN5-depleted HUVECs. Reverse effects on NF-κB activity and THP-1 arrest were seen upon CSN5 overexpression. Finally, double-immunostaining confirmed the expression of CSN subunits in the endothelium of human atherosclerotic lesions, and revealed an increased expression of CSN5 which correlated with atheroprogression. In conclusion, endothelial CSN5 attenuates NF-KB-dependent pro-inflammatory gene expression and monocyte arrest on stimulated endothelial cells in vitro, suggesting that CSN5 might serve as a negative regulator of atherogenesis.Note: The review process for this manuscript was fully handled by G. Y. H. Lip, Editor in Chief.

Cell-specific posttranscriptional regulation of CFTR gene expression via influence of MAPK cascades on 3′UTR part of transcripts

2005 ◽  
Vol 289 (5) ◽  
pp. C1240-C1250 ◽  
Author(s):  
Maryvonne Baudouin-Legros ◽  
Alexandre Hinzpeter ◽  
Amandine Jaulmes ◽  
Franck Brouillard ◽  
Bruno Costes ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Lines ◽  
Posttranscriptional Regulation ◽  
P38 Map Kinase ◽  
Cftr Gene ◽  
Control Of Gene Expression ◽  
Cytosolic Proteins ◽  
Tnf Α ◽  
Ht 29

Expression of the cystic fibrosis (CF) transmembrane conductance regulator (CFTR) gene, which contains the mutations responsible for CF, is regulated by cytokines (TNF-α and IL-1β) in a cell-specific manner. TNF-α decreases CFTR mRNA in human colon cell lines (HT-29), but not in pulmonary cell lines (Calu-3), and IL-1β increases it only in Calu-3 cells. We looked for the cytokine-induced posttranscriptional regulation of CFTR gene expression and studied the modulation of CFTR mRNA stability linked to its 3′ untranslated sequence (3′UTR) in HT-29 and Calu-3 cells. The stability of CFTR mRNA was analyzed by Northern blot after in vitro incubation of total RNAs from CFTR-expressing cells with cytosolic proteins extracted from control or cytokine-treated HT-29 and Calu-3 cells. CFTR mRNA was degraded only by extracts of TNF-α-treated HT-29 cells and not by cytosolic proteins from untreated or IL-1β-treated HT-29 cells. In contrast, extracts of untreated Calu-3 cells enhanced CFTR mRNA degradation, and IL-1β treatment inhibited this; TNF-α had no significant effect. The 3′UTR part of CFTR mRNA was found to be required for this posttranscriptional regulation. The 5′ part of the 3′UTR (the 217 first bases), which contains two AUUUA sequences, was implicated in CFTR mRNA destabilization and the following 136 bases, containing several C-repeats in U-rich environment, in its protection. The proteins, which reacted with the U- and C-repeats of CFTR mRNA 3′UTR, were mainly controlled by stimulation of the p42/p44 and p38 MAP kinase cascades with interaction between these pathways. This posttranscriptional control of gene expression is a common feature of CFTR and many proteins of inflammation.

CCL3 and CCL4, the Major Chemokines Produced by CD38+ Chronic Lymphocytic Leukemia Cells, Facilitate Microenvironmental Interactions of Neoplastic Cells Via the CD49d/VCAM Pair.

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 1055-1055
Author(s):  
Antonella Zucchetto ◽  
Dania Benedetti ◽  
Riccardo Bomben ◽  
Claudio Tripodo ◽  
Fleur Bossi ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Tumor Microenvironment ◽  
Tumor Cells ◽  
Umbilical Vein ◽  
Fold Increase ◽  
Peripheral Blood Cell ◽  
Lymphocytic Leukemia ◽  
Bone Marrow Biopsies ◽  
L Cells

Abstract CD38, a negative prognostic marker for patients with CLL, has been demonstrated to be a key molecule in the interactions occurring in the context of tumor microenvironment, mediating both survival and migratory signals for CLL cells. By taking advantage of gene expression profiling studies (GEP) comparing 11 CD38pos (CD38&gt;30%) and 15 CD38neg (CD38&lt;10%) CLLs, we identified as over-expressed in CD38pos CLL cells: i) genes for the two C-C chemokines CCL3 and CCL4 (median-log difference, MLD-CCL3= 3.5; MLD-CCL4=4.4); real-time quantitative PCR (RTQ-PCR) of selected cases confirmed GEP results; ii) the gene for CD49d (MLD=4.4); a high correlation between CD38 and CD49d protein expression, also characterizing the CLL series of the present study, has been reported previously. In vitro experiments, performed on purified tumor cells from additional 11 CD38pos CLL cases cultured for 14 (t14) and 24 (t24) hours in the presence of either the agonist anti-CD38 monoclonal antibody (mAb) IB4 or the non-agonistic anti-CD38 mAb IB6 as control, demonstrated upregulation of CCL3/CCL4 transcripts at t14 (CCL3: mean fold increase=18, p=0.041; CCL4: mean fold increase=13.8, p=0.005), as assessed by RTQ-PCR, and an increased release of CCL3/CCL4 proteins at t24 (CCL3: mean =0.9 ng/mL, mean fold increase=14, p=0.003; CCL4: mean =1.7 ng/mL, mean fold increase=49, p=0.01), as assessed by ELISA. Consistently, immunohistochemistry (IHC) analysis performed in bone marrow biopsies (BMB) from 20 CLL patients (10 CD38pos and 10 CD38neg cases) showed detectable levels of CCL3 in 8 cases, all but one belonging to the CD38pos group (p=0.02). Expression of the CCL3/CCL4 specific receptors CCR1 and CCR5 was examined by flow cytometry in peripheral blood cell subpopulations from 30 CLL (12 CD38pos and 18 CD38neg). Irrespectively of CD38 expression by CLL cells, monocytes showed the highest expression levels for CCR1 and, although at a lesser extent, CCR5. Consistently, CCL3 was able to attract CLL-derived monocytes by in-vitro chemotaxis experiments, and a higher number of infiltrating CD68pos macrophages were found in BMB of CD38pos compared to CD38neg CLLs (p=0.016). In parallel experiments, conditioned media (CM) from CCL3-stimulated macrophages were collected; these CM were able to induce expression of the CD49d-ligand VCAM in human umbilical vein endothelial cells (HUVEC) and human microvascular endothelial cells (ADMEC). As shown by ELISA, TNFalpha was among the cytokines contained in macrophage-CM. This citokine was likely responsible for VCAM up-regulation by HUVEC and ADMEC, as suggested by TNFalpha neutralization experiments leading to a suppression of VCAM-1 induction in endothelial cell models. Again, IHC analysis of CLL BMB showed a meshwork of VCAM-1-positive cells more prominent in the context of lymphoid infiltrates of CD38pos, as compared to CD38neg cases (p=0.002). To verify whether CD49d engagement through VCAM-1 could enhance the protection against spontaneous apoptosis of CLL cells in vitro, we cultured purified CD38pos/CD49dpos CLL cells from 5 cases onto VCAM-1-transfected L cells or mock-transfected L cells. Results demonstrated a substantial improvement in cell viability after CD49d engagement: as high as 70%±25 cells were viable after 10 days of culture on L-VCAM cells compared to 50%±25 in control conditions (p=0.009). Altogether, these results identify molecules involved in a functional cross-talk between CD38/CD49d-expressing CLL and cells of the tumor microenvironment. This interplay may eventually affect survival and recirculation of tumor cells via the CD49d/VCAM pair.

TNF-α-Mediated Tumor Promotion Is Characterized by Enhanced Vasculogenesis and Generation of Myeloid/Endothelial Vascular Leukoctyes.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 3905-3905
Author(s):  
Bin Li ◽  
Matthew Pagni ◽  
Justin Cates ◽  
D. Brent Polk ◽  
Pampee P. Young
Keyword(s):  
Myeloid Cells ◽  
Fold Increase ◽  
Vascular Density ◽  
Tnf Receptors ◽  
Blocking Antibody ◽  
Modest Contribution ◽  
Tnf Α ◽  
In Cells

Abstract Whereas in many contexts myeloid cells are cytotoxic, it is well-established that as yet unknown microenvironment cues instruct the infiltrating tumor associated myeloid cells (TAMs) to drive malignant progression and dissemination. Recently, we and others have characterized a significant subpopulation of tumor associated myeloid cells that co-express endothelial and myeloid markers designated “vascular leukocytes”. Studies suggest that vascular leukocytes play an important role in tumor progression and also demonstrate modest contribution to functional vessels, i.e. vasculogenesis, suggesting that they represent a critical tumor-promoting TAM subpopulation. We have identified TNFα as a key regulator of the vascular transdifferentiation of myeloid progenitors in vitro and within the tumor milieu. TNFα at 40ng/ml significantly increased the numbers of flk-1/VE-cadherin dual positive, early outgrowth EPCs from human CD14+ cells by day 7 (about five fold of the control), starting with increased spindle-shaped population appeared as early as day 3. Consistent with this, we observed increased flk-1 expression by ∼9-fold (p&lt;0.05) in cells treated with 40ng/ml TNFα by real time RT-PCR. Transcripts for VE-cadherin and tie2, both endothelial-enriched, were detected by day 3 in cells exposed to 40ng/ml TNFa but not in its absence (control). TNFα-directed upregulation of endothelial markers in mouse monocytes in vitro was dependent on TNFα receptors as monocytes isolated from mice lacking both TNF receptors displayed significantly delayed endothelial marker upregulation. These data suggested that TNF was a component of the molecular pathway that accelerated, but was not required for, endothelial transdifferentiation of murine and human myeloid cells. Enhanced TNFα expression in both B16 murine melanoma and PyV-mT tumor showed local TNFα significantly promoted tumor growth versus control (&gt;5-fold increase for B16 tumor, p=0.04; &gt;8-fold increase for PyV-mT tumor, p&lt;0.01). Both tumor models indicated that overexpressing TNFα caused higher vascular density over control, while tumor necrosis was significantly reduced. Additionally, we observed increased bone marrow-derived vessels (vasculogenesis) in mouse TNFα-overexpressing tumors, which can be specifically inhibited by an anti-TNFα blocking antibody. A significant increase in association of vascular leukoctyes was detected in tumors overexpressing TNFα by FACs, which was abrogated in the mice lacking TNF receptors. Interestingly, TNF-overexpressing tumors did not recruit greater overall numbers of tumor-associated (myeloid or lymphoid) leukocytes, suggesting a specific role in myeloid to endothelial transdifferentiation in vivo. Our studies suggest that TNFα constitutes part of the microenvironment repertoire that biases recruited myeloid cells towards a proangiogenic/provasculogenic phenotype.

scholarly journals Role of interleukin-1 and tumour necrosis factor in leukocyte recruitment to acute dermal inflammation

1992 ◽  
Vol 1 (5) ◽  
pp. 347-353 ◽  
Author(s):  
Andrew C. Issekutz ◽  
Nancy Lopes ◽  
Thomas B. Issekutz
Keyword(s):  
Monoclonal Antibody ◽  
Umbilical Vein ◽  
Interleukin 1 ◽  
E Coli ◽  
Tnf Α ◽  
Lps Activation ◽  
Necrosis Factor

The cytokines IL-1 and TNF-α are involved in inflammation and their production is stimulated by various agents, especially endotoxin (LPS). Here, using the human IL-1 receptor antagonist (IL-1RA) and a new monoclonal antibody (mAb 7F11) to rabbit TNF, the role of endogenous IL-l and TNF production in acute (3h) leukocyte (PMNL) recruitment to dermal inflammation in rabbits has been studied. IL-1RA inhibited by 27% the PMNL accumulation in reactions induced by killed Escherichia coli (p < 0.05) but not by LPS. The monoclonal antibody to TNF inhibited by 27% and 38% (p < 0.002) the PMNL accumulation in LPS and E. coli reactions respectively, but a combination of the mAb with IL-1RA was not more effective. Treatment of human umbilical vein endothelium with LPS for 3 h activated endothelium to induce PMNL transendothelial migration in vitro, which was not inhibited by IL-1RA, antibody to TNF-α, IL-1 or to IL-8. In conclusion, TNF and IL-1 may partially mediate acute PMNL infiltration in vivo to LPS and Gram negative bacteria, but there is a major IL-1/TNF independent mechanism, at least in dermal inflammation, which may be due to direct LPS activation of the microvasculature or perhaps the generation of cytokines other than IL-1 and TNF.

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