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Fan W, Adebowale K, Váncza L, Li Y, Rabbi MF, Kunimoto K, Chen D, Mozes G, Chiu DKC, Li Y, Tao J, Wei Y, Adeniji N, Brunsing RL, Dhanasekaran R, Singhi A, Geller D, Lo SH, Hodgson L, Engleman EG, Charville GW, Charu V, Monga SP, Kim T, Wells RG, Chaudhuri O, Török NJ. Matrix viscoelasticity promotes liver cancer progression in the pre-cirrhotic liver. Nature 2024; 626:635-642. [PMID: 38297127 PMCID: PMC10866704 DOI: 10.1038/s41586-023-06991-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 12/18/2023] [Indexed: 02/02/2024]
Abstract
Type 2 diabetes mellitus is a major risk factor for hepatocellular carcinoma (HCC). Changes in extracellular matrix (ECM) mechanics contribute to cancer development1,2, and increased stiffness is known to promote HCC progression in cirrhotic conditions3,4. Type 2 diabetes mellitus is characterized by an accumulation of advanced glycation end-products (AGEs) in the ECM; however, how this affects HCC in non-cirrhotic conditions is unclear. Here we find that, in patients and animal models, AGEs promote changes in collagen architecture and enhance ECM viscoelasticity, with greater viscous dissipation and faster stress relaxation, but not changes in stiffness. High AGEs and viscoelasticity combined with oncogenic β-catenin signalling promote HCC induction, whereas inhibiting AGE production, reconstituting the AGE clearance receptor AGER1 or breaking AGE-mediated collagen cross-links reduces viscoelasticity and HCC growth. Matrix analysis and computational modelling demonstrate that lower interconnectivity of AGE-bundled collagen matrix, marked by shorter fibre length and greater heterogeneity, enhances viscoelasticity. Mechanistically, animal studies and 3D cell cultures show that enhanced viscoelasticity promotes HCC cell proliferation and invasion through an integrin-β1-tensin-1-YAP mechanotransductive pathway. These results reveal that AGE-mediated structural changes enhance ECM viscoelasticity, and that viscoelasticity can promote cancer progression in vivo, independent of stiffness.
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Affiliation(s)
- Weiguo Fan
- Gastroenterology and Hepatology, Stanford University, Stanford, CA, USA
- VA, Palo Alto, CA, USA
| | - Kolade Adebowale
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA
- Chemistry, Engineering and Medicine for Human Health (ChEM-H), Stanford University, Stanford, CA, USA
| | - Lóránd Váncza
- Gastroenterology and Hepatology, Stanford University, Stanford, CA, USA
- VA, Palo Alto, CA, USA
| | - Yuan Li
- Gastroenterology and Hepatology, Stanford University, Stanford, CA, USA
- VA, Palo Alto, CA, USA
| | - Md Foysal Rabbi
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
| | - Koshi Kunimoto
- Gastroenterology and Hepatology, Stanford University, Stanford, CA, USA
- VA, Palo Alto, CA, USA
| | - Dongning Chen
- Gastroenterology and Hepatology, Stanford University, Stanford, CA, USA
- VA, Palo Alto, CA, USA
| | - Gergely Mozes
- Gastroenterology and Hepatology, Stanford University, Stanford, CA, USA
- VA, Palo Alto, CA, USA
| | - David Kung-Chun Chiu
- Department of Pathology, Stanford University, Stanford, CA, USA
- Division of Immunology, Stanford University, Stanford, CA, USA
| | - Yisi Li
- Department of Automation, Tsinghua University, Beijing, China
| | - Junyan Tao
- Pittsburgh Liver Research Center, University of Pittsburgh and University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Yi Wei
- Gastroenterology and Hepatology, Stanford University, Stanford, CA, USA
- VA, Palo Alto, CA, USA
| | - Nia Adeniji
- Gastroenterology and Hepatology, Stanford University, Stanford, CA, USA
- VA, Palo Alto, CA, USA
| | - Ryan L Brunsing
- Department of Radiology, Stanford University, Stanford, CA, USA
| | - Renumathy Dhanasekaran
- Gastroenterology and Hepatology, Stanford University, Stanford, CA, USA
- VA, Palo Alto, CA, USA
| | - Aatur Singhi
- Pittsburgh Liver Research Center, University of Pittsburgh and University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - David Geller
- Pittsburgh Liver Research Center, University of Pittsburgh and University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Su Hao Lo
- Department of Biochemistry and Molecular Medicine, University of California at Davis, Sacramento, CA, USA
| | - Louis Hodgson
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, New York, NY, USA
| | - Edgar G Engleman
- Department of Pathology, Stanford University, Stanford, CA, USA
- Division of Immunology, Stanford University, Stanford, CA, USA
| | | | - Vivek Charu
- Department of Pathology, Stanford University, Stanford, CA, USA
- Quantitative Sciences Unit, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Satdarshan P Monga
- Pittsburgh Liver Research Center, University of Pittsburgh and University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Taeyoon Kim
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
- Faculty of Science and Technology, Keio University, Yokohama, Japan
| | - Rebecca G Wells
- Departments of Medicine and Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Ovijit Chaudhuri
- Chemistry, Engineering and Medicine for Human Health (ChEM-H), Stanford University, Stanford, CA, USA
- Department of Mechanical Engineering, Stanford University, Stanford, CA, USA
| | - Natalie J Török
- Gastroenterology and Hepatology, Stanford University, Stanford, CA, USA.
- VA, Palo Alto, CA, USA.
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Kapoor K, Eissa N, Rabbi MF, Kermarrec L, Gupta G, uzonna J, Bernstein CN, Ghia J. A83 CHROMOFUNGIN DECREASES INTESTINAL INFLAMMATION AND REGULATES DENDRITIC CELLS MARKERS. J Can Assoc Gastroenterol 2018. [DOI: 10.1093/jcag/gwy009.083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- K Kapoor
- Immunology, University of Manitoba, Winnipeg, MB, Canada
| | - N Eissa
- Immunology, University of Manitoba, Winnipeg, MB, Canada
| | - M F Rabbi
- Immunology and Internal Medicine Section of Gastroenterology, University of Manitoba, Winnipeg, MB, Canada
| | - L Kermarrec
- Immunology, University of Manitoba, Winnipeg, MB, Canada
| | - G Gupta
- Immunology and Internal Medicine Section of Gastroenterology, University of Manitoba, Winnipeg, MB, Canada
| | - J uzonna
- Immunology and Internal Medicine Section of Gastroenterology, University of Manitoba, Winnipeg, MB, Canada
| | - C N Bernstein
- Immunology, University of Manitoba, Winnipeg, MB, Canada
| | - J Ghia
- Immunology and Internal Medicine Section of Gastroenterology, University of Manitoba, Winnipeg, MB, Canada
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Hasan MZ, Ishika A, Ullah TR, Rabbi MF, Jesmin. P-84 Association between HIF1A rs11549465 C/T polymorphism and elite athlete. Br J Sports Med 2016. [DOI: 10.1136/bjsports-2016-097120.137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Polaszek A, Rabbi MF, Islam Z, Buckley YM. Trichogramma zahiri (Hymenoptera: Trichogrammatidae) an egg parasitoid of the rice hispa Dicladispa armigera (Coleoptera: Chrysomelidae) in Bangladesh. Bull Entomol Res 2002; 92:529-37. [PMID: 17598304 DOI: 10.1079/ber2002197] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Trichogramma zahiri Polaszek sp. n. is described from Bangladesh. It has been collected at several localities from the major pest of rice Dicladispa armigera (Olivier) on which it has an important controlling impact. Trichogramma zahiri is compared with known Trichogramma species from the region, and diagnostic differences are presented. Data on developmental period, adult longevity, egg-laying frequency, host egg age preference and seasonal parasitism rate are presented and discussed. Other records of parasitoids of D. armigera are briefly reviewed and discussed.
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Affiliation(s)
- A Polaszek
- Department of Entomology, The Natural History Museum, Cromwell Road, London, SW7 5BD, UK.
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Ghassemi M, Andersen BR, Roebuck KA, Rabbi MF, Plate JM, Novak RM. Mycobacterium avium complex activates nuclear factor kappaB via induction of inflammatory cytokines. Cell Immunol 1999; 191:117-23. [PMID: 9973533 DOI: 10.1006/cimm.1998.1419] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A variety of microorganisms has been reported to directly induce NF-kappaB, a critical step in the regulation of genes involved in the cellular immune response. In this study, we demonstrate that proinflammatory cytokines such as tumor necrosis factor alpha (TNFalpha) produced upon activation by the Mycobacterium avium complex (MAC) preceed NF-kappaB activity in U937, a human monocytoid cell line. MAC induction of TNFalpha mRNA expression was detected within 15 min after MAC infection, whereas enhanced NF-kappaB binding activity was not detected until 90 to 120 min postinfection. Supershift analysis revealed increased p50 in the MAC-induced NF-kappaB binding complexes. Consistent with an autocrine mechanism, anti-TNFalpha antibody and dexamethasone, a known cytokine inhibitor, both completely suppressed the effect of MAC on the induction of NF-kappaB. Taken together, these findings suggest that exposure of monocyte cell membranes to MAC induces endogenous TNFalpha, which in turn enhances NF-kappaB binding activity. The rapid induction of TNFalpha may be important in the initial host response to MAC infection.
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Affiliation(s)
- M Ghassemi
- Department of Medicine, University of Illinois, Chicago, Illinois, 60612, USA.
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Rabbi MF, Finnegan A, Al-Harthi L, Song S, Roebuck KA. Interleukin-10 enhances tumor necrosis factor-alpha activation of HIV-1 transcription in latently infected T cells. J Acquir Immune Defic Syndr Hum Retrovirol 1998; 19:321-31. [PMID: 9833740 DOI: 10.1097/00042560-199812010-00002] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Interleukin-10 (IL-10) is elevated in HIV-1-infected individuals and has been implicated in disease progression. We previously reported that IL-10 cooperates with tumor necrosis factor-alpha (TNF-alpha) to activate HIV-1 expression synergistically in acutely infected monocyte-derived macrophages and the chronically infected U1 promonocytic cell line. To determine whether IL-10 also cooperates with TNF-alpha to activate latent HIV-I expression in lymphocytes, we examined the effects of IL-10 on proviral expression in the chronically infected T-cell line, ACH-2. Although IL-10 inhibited HIV-1 expression acting alone, in combination with suboptimal concentrations of TNF-alpha, IL-10 increased HIV-1 steady-state mRNA expression and p24 core antigen production in ACH-2 cells. Interestingly, IL-10 concentrations that synergistically induced virus also maximally stimulated endogenous TNF-alpha expression, suggesting that cell-derived TNF-alpha may contribute to cytokine synergy. Transfection studies in ACH-2 cells indicated that IL-10 combined with TNF-alpha to activate the HIV-1 long terminal repeat (LTR). IL-10 also cooperated with TNF-alpha to activate HIV-1 LTR in 1G5 cells, a Jurkat T-cell line stably transfected with an LTR-dependent luciferase reporter gene. Pyrrolidine dithiocarbamate, a potent transcriptional inhibitor of the viral LTR, abrogated the cytokine responses in both U1 and ACH-2 cells, suggesting a common TNF-alpha-mediated transcriptional mechanism in these cell types despite their different modes of provirus latency. Taken collectively, these data suggest that IL-10 enhances suboptimal TNF-alpha activation of HIV-1 transcription in chronically infected T-cells at least in part through induction of endogenous TNF-alpha expression.
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Affiliation(s)
- M F Rabbi
- Department of Immunology/Microbiology, Rush Presbyterian St. Luke's Medical School Chicago, Illinois, USA
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Rabbi MF, al-Harthi L, Saifuddin M, Roebuck KA. The cAMP-dependent protein kinase A and protein kinase C-beta pathways synergistically interact to activate HIV-1 transcription in latently infected cells of monocyte/macrophage lineage. Virology 1998; 245:257-69. [PMID: 9636365 DOI: 10.1006/viro.1998.9158] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The HIV-1 long terminal repeat (LTR) responds to a variety of cellular signal transduction pathways. We demonstrate that the cAMP-dependent protein kinase A (PKA) and protein kinase C (PKC) signaling pathways synergize to increase HIV-1 LTR-mediated transcription and viral replication in a latently infected promonocytic cell line (U1). The LTR-mediated synergy induced by cholera toxin (Ctx), a potent activator of the cAMP-dependent PKA pathway, and the PKC activator phorbol 12-myristate 13-acetate (PMA) was abrogated by a PKC-beta-specific inhibitor (LY333531). In contrast, the LTR-mediated synergy induced by Ctx and TNF alpha was not affected by LY333531. The synergy induced by Ctx and TNF alpha was also abrogated by mutation of the cAMP-responsive downstream sequence elements (DSE) in the 5' untranslated leader region, whereas the DSE mutations did not affect the synergy induced by Ctx and PMA. These distinctions indicate that Ctx cooperates differently with TNF alpha and PMA to activate the HIV-1 LTR. Ctx and PMA synergistically activated AP-1- and NF-kappa B-dependent transcription, even though no cooperative binding of AP-1 or NF-kappa B was observed in gel shift assays. An extensive mutational analysis of the HIV-1 LTR that included the NF-kappa B and AP-1 binding sites revealed no distinct cis-acting element or region within the HIV-1 LTR that was required for the transcriptional synergy. Ctx and PMA also synergistically interact to activate the HTLV-1 LTR. These results indicate that the transcriptional synergy elicited by Ctx and PMA targets multiple functional elements and promoters, requires a cooperative interaction between the PKA and PKC-beta pathways, and differs mechanistically from the transcriptional synergy induced by Ctx and TNF alpha.
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Affiliation(s)
- M F Rabbi
- Department of Immunology/Microbiology, Rush-Presbyterian-St. Luke's Medical Center, Chicago, Illinois 60612, USA
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Rabbi MF, Al-Harthi L, Roebuck KA. TNFalpha cooperates with the protein kinase A pathway to synergistically increase HIV-1 LTR transcription via downstream TRE-like cAMP response elements. Virology 1997; 237:422-9. [PMID: 9356353 DOI: 10.1006/viro.1997.8798] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Activating protein-1 (AP-1) binding TPA responsive elements (TRE) are located downstream of the transcription initiation site in the U5 region of the HIV-1 long terminal repeat (LTR). These downstream sequence elements, termed DSE, can bind both AP-1 and CREB/ATF transcription factors. Recently, we demonstrated that the DSE are also cAMP-responsive elements (CRE), since they mediated activation signals elicited by cholera toxin (Ctx), a potent activator of the cAMP-dependent protein kinase A (PKA) signal transduction pathway. In the present study, we demonstrate that the HIV-1 DSE can mediate the transcriptional synergy elicited by the combination of Ctx and TNFalpha. Ctx combined with TNFalpha or IL-1beta to produce a synergistic increase in p24 antigen production in U1 promonocytic cells. Transfection studies of LTR reporter constructs indicated that mutation of the DSE sites abrogated the LTR-mediated synergy induced by Ctx and TNFalpha, whereas the synergy induced by Ctx and IL-1beta was unaffected, suggesting TNFalpha and IL-1beta cooperate differently with the cAMP/PKA activation pathway to induce HIV-1 expression in U1 cells. Because the DSE are also TRE sites, we assessed the effect of the agonist combinations on AP-1-dependent transcription. TNFalpha as well as IL-1beta cooperated with Ctx to produce a synergistic activation of AP-1-mediated transcription. These data indicate that the TRE-like cAMP-responsive DSE sites within the 5'-untranslated leader can mediate the transcriptional cooperativity between TNFalpha and the cAMP/PKA pathway. Since the DSE and TRE sites cannot bind CREB/ATF homodimers, we propose a mechanism in which the HIV-1 DSE bind heterodimers composed of both AP-1 and CREB/ATF proteins.
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Affiliation(s)
- M F Rabbi
- Department of Immunology/Microbiology, Rush-Presbyterian-St. Luke's Medical Center, 1653 West Congress Parkway, Chicago, Illinois 60612, USA
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Rabbi MF, Saifuddin M, Gu DS, Kagnoff MF, Roebuck KA. U5 region of the human immunodeficiency virus type 1 long terminal repeat contains TRE-like cAMP-responsive elements that bind both AP-1 and CREB/ATF proteins. Virology 1997; 233:235-45. [PMID: 9201233 DOI: 10.1006/viro.1997.8602] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Activating protein-1 (AP-1) binding phorbol ester responsive elements (TRE) are located downstream of the transcription initiation site in the U5 region of the human immunodeficiency virus type-1 (HIV-1) long terminal repeat (LTR). These downstream sequence elements, termed DSE, can bind cFos and junD and transmit protein kinase C (PKC) activation signals to the LTR. Further studies suggested the DSE might also bind AP-1-related proteins of the CREB/ATF family. Since enhanced HIV-1 expression is associated with activation of the cAMP-dependent protein kinase A (PKA) signaling pathway, we determined whether binding of CREB/ATF proteins to the DSE mediate cAMP/PKA activation of the HIV-1 LTR. In the present study. DSE binding complexes in nuclear protein extracta from colonic epithelial cells are shown to contain ATF-1, ATF-2, and CREB and transfection of either an ATF-2 or PKA expressing plasmid transactivated the DSE. Cholera toxin (Ctx), a potent activator of the cAMP/PKA pathway. Increased HIV-1 virus production from a latently infected promonocytic cell line, U1. Ctx increased LTR promoter activity and increased the CREB content of DSE binding complexes. Transfection of U1 cells with a series of mutant LTR reporter constructs demonstrated that the Ctx response was in large part mediated by the DSE. The Ctx response was also mediated by a heterologous promoter containing multiple TRE sites. Nuclear protein extracts from a T-cell line infected by HIV-1 contained higher levels of CREB/ATF proteins and manifested increased CREB/ATF binding activity. Collectively, these results indicate the DSE are TRE-like cAMP responsive elements that bind both AP-1 and CREB/ATF permitting induction of the HIV-1 LTR by both PKC and PKA activation signals.
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Affiliation(s)
- M F Rabbi
- Department of Immunology and Microbiology, Rush-Presbyterian-St. Luke's Medical Center, Chicago, Illinois 60612, USA
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Song S, Ling-Hu H, Roebuck KA, Rabbi MF, Donnelly RP, Finnegan A. Interleukin-10 inhibits interferon-gamma-induced intercellular adhesion molecule-1 gene transcription in human monocytes. Blood 1997; 89:4461-9. [PMID: 9192770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Interleukin-10 (IL-10) is a potent monocyte regulatory cytokine that inhibits gene expression of proinflammatory mediators. In this study, we investigated the mechanism by which IL-10 downregulates expression of intercellular adhesion molecule-1 (ICAM-1) on the cell surface of normal human monocytes activated with interferon-gamma (IFN-gamma). IL-10 inhibition of IFN-gamma-induced ICAM-1 expression was apparent as early as 3 hours and was blocked by an anti-IL-10 antibody but not by an isotype-matched control antibody. Northern blot analysis showed that IL-10 reduced the accumulation of ICAM-1 mRNA in IFN-gamma-stimulated monocytes. IL-10 inhibition of ICAM-1 steady-state mRNA was detected at 3 hours and remained at 24 hours. Nuclear run-on transcription assays showed that IL-10 inhibited the rate of IFN-gamma-induced transcription of the ICAM-1 gene, and mRNA stability studies showed that IL-10 did not alter the half-life of IFN-gamma-induced ICAM-1 message. Thus, IL-10 inhibits IFN-gamma-induced ICAM-1 expression in monocytes primarily at the level of gene transcription. Activation of IFN-gamma-responsive genes requires tyrosine phosphorylation of the transcriptional factor STAT-1alpha (signal transducer and activator of transcription-1alpha). However, IL-10 did not affect IFN-gamma-induced tyrosine phosphorylation of STAT-1alpha or alter STAT-1alpha binding to the IFN-gamma response element (IRE) in the ICAM-1 promoter. Instead, IL-10 prevented IFN-gamma-induced binding activity at the NF-kappaB site of the tumor necrosis factor alpha (TNF-alpha)-responsive NF-kappaB/C-EBP composite element in the ICAM-1 promoter. These data indicate that IL-10 inhibits IFN-gamma-induced transcription of the ICAM-1 gene by a regulatory mechanism that may involve NF-kappaB.
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Affiliation(s)
- S Song
- Department of Medicine, Rush Presbyterian-St Luke's Medical Center, Chicago, IL 60612, USA
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Roebuck KA, Rabbi MF, Kagnoff MF. HIV-1 Tat protein can transactivate a heterologous TATAA element independent of viral promoter sequences and the trans-activation response element. AIDS 1997; 11:139-46. [PMID: 9030359 DOI: 10.1097/00002030-199702000-00002] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE To determine whether the HIV-1 transactivator protein Tat acts as a DNA sequence-specific transcription factor and activates transcription from a heterologous TATAA element in the absence of the trans-activation response (TAR) element and other sequences in the HIV-1 long terminal repeat (LTR). DESIGN Activating protein-1 (AP-1) and Tat-induced transcription were assessed using Jun and hybrid Tat/Jun-expression plasmids and reporter gene constructs which contained AP-1 binding sites upstream of the rat prolactin TATAA element or an HIV-1 LTR construct in which AP-1 binding sites replaced the TAR element. METHODS Tat-induced transcription was determined following transient transfection of colon epithelial cell lines with reporter gene constructs and Tat/Jun-expression plasmids in which Tat was fused to the DNA binding domain of Jun. Activation of prolactin (PL) and LTR reporter genes was assessed by luciferase (LUC) or chloramphenicol acetyltransferase (CAT) activity in cellular extracts. RESULTS Cotransfection of cells with Tat/Jun and the AP-1 PL LUC or LTR AP-1 CAT reporter plasmid resulted in a marked increase in reporter gene activity which was comparable with that induced by transfection of cells with several different AP-1 expression plasmids (e.g., JunD, JunB, c-Fos), or that elicited by stimulation of the cells transfected with LTR AP-1 CAT plasmids with phorbol ester or tumor necrosis factor-alpha. Tat-induced transcription was DNA-mediated since both a Jun DNA binding domain fused to Tat as well as AP-1 binding sites within the promoter were required for the induction of CAT expression. CONCLUSIONS Tat-activated transcriptor can occur strictly through a heterologous TATAA element independent of TAR and Sp1 binding sites or other HIV-1 LTR sequences. Tat appears to increase transcription initiated through the TATAA element by mechanisms similar to that of DNA sequence-specific transcription factors.
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Affiliation(s)
- K A Roebuck
- Department of Immunology and Microbiology, Rush Presbyterian-St Luke's Medical Center, Chicago, Illinois 60612, USA
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Finnegan A, Roebuck KA, Nakai BE, Gu DS, Rabbi MF, Song S, Landay AL. IL-10 cooperates with TNF-alpha to activate HIV-1 from latently and acutely infected cells of monocyte/macrophage lineage. J Immunol 1996; 156:841-51. [PMID: 8543841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
IL-10 is elevated in HIV-1-infected individuals and has been implicated in disease progression. In this study, we investigated the effects of IL-10 on the activation of HIV-1 from infected monocytes and macrophages. Although IL-10 alone did not induce HIV-1 replication, in the presence of TNF-alpha, IL-10 markedly enhanced virion production from a chronically infected promonocytic cell line (U1) and in acutely infected monocyte-derived macrophages. Neutralizing mAbs to IL-10 and TNF-alpha indicated that both cytokines were essential for the induction and were required to generate a synergistic increase in virus expression. The effects of the two cytokines were distinguishable functionally since pretreatment with TNF-alpha attenuated the cytokine cooperativity, while pretreatment with IL-10 potentiated their cooperativity, suggesting that IL-10 and TNF-alpha play different roles in the activation of virus. Northern blot analysis as well as Ab blocking and cytokine secretion studies indicated that the induction of either endogenous TNF-alpha or IL-10 was not involved in the cooperativity, nor was an up-regulation of TNF-alpha receptors. In combination with TNF-alpha, IL-10 stimulated activating protein-1 (AP-1) and nuclear factor (NF)-kappa B binding activities and cooperated to increase HIV-1 steady-state mRNA levels and enhance long terminal repeat-directed transcription through activation of the NF-kappa B binding sites, suggesting the IL-10 effect occurs at least in part at the transcriptional level. These results indicate that IL-10, in addition to down-regulating the cellular immune response to HIV-1, may also play a role in TNF-alpha-mediated activation of HIV-1 replication in the monocyte/macrophage lineage.
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Affiliation(s)
- A Finnegan
- Department of Medicine, Rush-Presbyterian-St. Luke's Medical Center, Chicago, IL 60612, USA
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13
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Finnegan A, Roebuck KA, Nakai BE, Gu DS, Rabbi MF, Song S, Landay AL. IL-10 cooperates with TNF-alpha to activate HIV-1 from latently and acutely infected cells of monocyte/macrophage lineage. The Journal of Immunology 1996. [DOI: 10.4049/jimmunol.156.2.841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Abstract
IL-10 is elevated in HIV-1-infected individuals and has been implicated in disease progression. In this study, we investigated the effects of IL-10 on the activation of HIV-1 from infected monocytes and macrophages. Although IL-10 alone did not induce HIV-1 replication, in the presence of TNF-alpha, IL-10 markedly enhanced virion production from a chronically infected promonocytic cell line (U1) and in acutely infected monocyte-derived macrophages. Neutralizing mAbs to IL-10 and TNF-alpha indicated that both cytokines were essential for the induction and were required to generate a synergistic increase in virus expression. The effects of the two cytokines were distinguishable functionally since pretreatment with TNF-alpha attenuated the cytokine cooperativity, while pretreatment with IL-10 potentiated their cooperativity, suggesting that IL-10 and TNF-alpha play different roles in the activation of virus. Northern blot analysis as well as Ab blocking and cytokine secretion studies indicated that the induction of either endogenous TNF-alpha or IL-10 was not involved in the cooperativity, nor was an up-regulation of TNF-alpha receptors. In combination with TNF-alpha, IL-10 stimulated activating protein-1 (AP-1) and nuclear factor (NF)-kappa B binding activities and cooperated to increase HIV-1 steady-state mRNA levels and enhance long terminal repeat-directed transcription through activation of the NF-kappa B binding sites, suggesting the IL-10 effect occurs at least in part at the transcriptional level. These results indicate that IL-10, in addition to down-regulating the cellular immune response to HIV-1, may also play a role in TNF-alpha-mediated activation of HIV-1 replication in the monocyte/macrophage lineage.
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Affiliation(s)
- A Finnegan
- Department of Medicine, Rush-Presbyterian-St. Luke's Medical Center, Chicago, IL 60612, USA
| | - K A Roebuck
- Department of Medicine, Rush-Presbyterian-St. Luke's Medical Center, Chicago, IL 60612, USA
| | - B E Nakai
- Department of Medicine, Rush-Presbyterian-St. Luke's Medical Center, Chicago, IL 60612, USA
| | - D S Gu
- Department of Medicine, Rush-Presbyterian-St. Luke's Medical Center, Chicago, IL 60612, USA
| | - M F Rabbi
- Department of Medicine, Rush-Presbyterian-St. Luke's Medical Center, Chicago, IL 60612, USA
| | - S Song
- Department of Medicine, Rush-Presbyterian-St. Luke's Medical Center, Chicago, IL 60612, USA
| | - A L Landay
- Department of Medicine, Rush-Presbyterian-St. Luke's Medical Center, Chicago, IL 60612, USA
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