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Jyonouchi H, Sun S. The actions of polynucleotides on effector stage cloned murine T-helper cells differ in each subset and depend on antigen concentration. J Nutr 1997; 127:411-7. [PMID: 9082024 DOI: 10.1093/jn/127.3.411] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Polynucleotides enhance T-helper (Th) cell-mediated humoral immune responses in naive resting Th cells, B cells, and antigen-presenting cells (APC) from unprimed mouse spleen. If polynucleotides augment Th cell functions independent of the activation stage of Th cells, then polynucleotides may cause hyperimmune responses. In this study we examined the effects of polynucleotides on effector-stage murine Th cell clones in vitro. The A.E7 clone (primed with pigeon cytochrome C, origin: B10.A mice) and CDC35 clone (primed with rabbit gamma-globulin, origin: DBA/2 mice) were used as representative type 1 (Th1) and type 2 (Th2) Th cells, respectively. Th clones were stimulated with antigen (Ag) in polynucleotide-supplemented or control cultures in the presence of syngeneic spleen cells (either CD4- or irradiated). The number of antibody (Ab)-secreting cells was counted to measure T-dependent Ab production. Production of interferon-gamma (IFNgamma) for the Th1 clone and interleukin-5 (IL-5) for the Th2 clone were measured. Without Ag stimulation, cytokine production and the number of Ab-secreting cells formed were very low and not altered by polynucleotides. With suboptimal Ag challenges provided by Ag-primed spleen cells, polynucleotides enhanced IFNgamma production by the Th1 clone, while they suppressed Th1 clone-mediated Ab production and IL-5 production by the Th2 clone. Polynucleotides did not alter Th2 clone-mediated Ab production. These actions of polynucleotides appeared to be dose-dependent. With optimal Ag challenges, polynucleotides did not affect our measures of Th cell activation. Polynucleotide action in vitro on effector-stage Th cell clones differed in each Th cell subset and depended on Ag concentration.
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Affiliation(s)
- H Jyonouchi
- Department of Pediatrics, School of Medicine, University of Minnesota, Minneapolis 55455, USA
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2
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Leuck J, Kuusksalu A, Kelve M, Vlassov V, Müller W, Schröder H. Modulation of the Antiviral 2-5A System in Human Immunodeficiency Virus-1-Infected CEM Cells by Propentofylline. Antivir Chem Chemother 1996. [DOI: 10.1177/095632029600700605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
2′,5′-OIigoadenylates (2-5A) play an essential role in the establishment of the antiviral state of cells exposed to virus infection. However, - after an initial increase observed in some cell lines - the activity of the interferon (IFN)-inducible, 2-5A-forming 2′,5′-oligoadenylate synthetase (2-5A synthetase) strongly decreases soon after infection of cells with the human immunodeficiency virus-1 (HIV-1). In the present report, we show that in IFN-treated human T lymphoblastoid CEM cells, the decrease in 2-5A synthetase activity had already occurred at day 1 post infection (p.i.)- At days 3 and 5 p.i., the 2-5A synthetase activity in the IFN-treated infected cells amounted to only 10-12% of that in IFN-treated uninfected control cells. The decrease in 2-5A synthetase activity was accompanied by a decrease in 2-5A synthetase mRNA and protein. We found that the decrease in 2-5A synthetase activity can be retarded by addition of the cAMP phosphodiesterase inhibitor, propentofylline. At a concentration of 30-100 μM, propentofylline displayed a significant cytoprotective and antiviral effect on HIV-1-infected CEM cells.
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Affiliation(s)
- J. Leuck
- Institut für Physiologische Chemie, Universität, Duesbergweg 6, D-55099 Mainz, Germany
| | - A. Kuusksalu
- Institute of Chemical Physics and Biophysics, Akadeemia tee 23, EE-0026 Tallinn, Estonia
| | - M. Kelve
- Institute of Chemical Physics and Biophysics, Akadeemia tee 23, EE-0026 Tallinn, Estonia
| | - V. Vlassov
- Institute of Bioorganic Chemistry, Siberian Division of Russian Academy of Sciences, Lavrentiev Avenue 8, 630090 Novosibirsk, Russia
| | - W.E.G. Müller
- Institut für Physiologische Chemie, Universität, Duesbergweg 6, D-55099 Mainz, Germany
| | - H.C. Schröder
- Institut für Physiologische Chemie, Universität, Duesbergweg 6, D-55099 Mainz, Germany
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3
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Wild JS, Hyde DM, Hubbell HR, Giri SN. Dose-related effects of Ampligen (poly(I).poly(C12U)), a mismatched double-stranded RNA, in a bleomycin-mouse model of pulmonary fibrosis. Exp Lung Res 1996; 22:375-91. [PMID: 8792127 DOI: 10.3109/01902149609031781] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The antifibrotic effect of the mismatched double-stranded RNA, Ampligen (poly(I).poly(C12U)), was evaluated in a bleomycin-mouse model of pulmonary fibrosis. Mice received a single intratracheal dose of bleomycin (0.125 U/mouse) or saline (50 microL) at the beginning of the experiment, followed by 5 or 6 intraperitoneal injections of Ampligen (1.0, 5.0, 10.0, 15.0, or 25.0 mg/kg) or saline at regular intervals for 2 weeks. Ampligen did not produce increased mortality or weight loss by itself. However, it produced varying degrees of mortality in combination with bleomycin. Five injections of 10 mg/kg Ampligen or three injections of 25 mg/kg Ampligen plus three injections of 10 mg/kg Ampligen in combination with bleomycin .produced significant reductions in lung collagen accumulation as indicated by lung hydroxyproline content compared to the bleomycin control group. Animals receiving bleomycin plus Ampligen at all dosages had significantly reduced prolyl hydroxylase activity compared to the bleomycin control group. Lipid peroxidation and bronchoalveolar lavage fluid (BALF)-supernatant protein content for the groups receiving bleomycin plus Ampligen were not reduced compared to the bleomycin control group. In the BALF-supernatant, the activity of acid phosphatase, a lysosomal enzyme produced by neutrophils, monocytes, and macrophages, was significantly decreased in the group receiving bleomycin plus 10 mg/kg Ampligen. Also, selected BALF differential immune cell counts were reduced in some of the groups receiving bleomycin plus Ampligen, but not in a consistent or dose-dependent manner. The results of this study indicate that Ampligen can significantly reduce the bleomycin-induced increased collagen accumulation and may be therapeutically useful in the management of lung fibrosis in humans.
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Affiliation(s)
- J S Wild
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis 95616, USA
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4
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Nicholson AW. Structure, reactivity, and biology of double-stranded RNA. PROGRESS IN NUCLEIC ACID RESEARCH AND MOLECULAR BIOLOGY 1996; 52:1-65. [PMID: 8821257 DOI: 10.1016/s0079-6603(08)60963-0] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- A W Nicholson
- Department of Biological Sciences, Wayne State University, Detroit, Michigan 48202, USA
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5
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Abstract
The high affinity of even relatively short sequences of DNA for their target mRNA suggests that antisense agents represent an ideal method of suppressing specific gene products both in vitro and in vivo. In experiments performed thus far, an effect on the target mRNA in cultured vascular cells and in the vessel wall can be documented. The in vitro activity, toxicity, and pharmacokinetic data of antisense oligonucleotides are encouraging, and the in vivo animal experiments demonstrating suppression of neointimal formation are very promising. If animals trials presently under way show continued suppression not only of intimal formation but also of loss of lumen caliber after a single application, then effective delivery of antisense oligonucleotides is a realistic possibility. Nevertheless, some words of caution regarding the use of antisense oligonucleotides are warranted. Potential nonspecific effects of antisense oligonucleotides should be carefully considered in studies in which antisense agents are used to define biological functions of specific genes. In particular, demonstration that the target mRNA has been suppressed does not prove that other sequences within the mRNA pool have not also been suppressed. Critical control measures include adding back the target mRNA or protein and demonstrating similar biological effects with antisense sequences, which also suppress target gene expression directed at different regions of the target mRNA. At the clinical level, the systemic effects of antisense oligonucleotides, the dosage required, the timing of administration compared with mechanical intervention, and the toxicity of breakdown products all need to be established. In addition, the most appropriate targets for antisense use in restenosis remain largely obscure. Indiscriminate suppression of cell-cycle genes or proto-oncogenes may be as acutely toxic as current anticancer chemotherapy if the site delivery is not completely localized. Furthermore, much of the clinical evidence suggests that restenosis is a chronic process, continuing to develop weeks to months after the procedure. If this is the case, then the current approaches that rely on a transient, local application of an antisense agent may fail. If, however, a target gene is identified that is specific to vascular tissue, then repeated administration of an antisense agent may be tolerated via a systemic route. This approach has proved successful in targeting mutated genes with little suppression of closely related genes and with minimal systemic toxicity. An alternative approach is to transfect the target tissue with a gene that makes it susceptible to systemic delivery of a drug that is not normally toxic to mammalian cells.(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- M R Bennett
- Department of Pathology, University of Washington, Seattle, USA
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6
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Roger PP, Reuse S, Maenhaut C, Dumont JE. Multiple facets of the modulation of growth by cAMP. VITAMINS AND HORMONES 1995; 51:59-191. [PMID: 7483330 DOI: 10.1016/s0083-6729(08)61038-9] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- P P Roger
- Institute of Interdisciplinary Research, Free University of Brussels, Belgium
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7
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Müller WE, Ushijima H, Schröder HC. Mechanism of the antiretroviral effect of dsRNA. PROGRESS IN MOLECULAR AND SUBCELLULAR BIOLOGY 1994; 14:66-88. [PMID: 7914807 DOI: 10.1007/978-3-642-78549-8_5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- W E Müller
- Institut für Physiologische Chemie, Abteilung Angewandte Molekularbiologie, Johannes Gutenberg-Universität, Mainz, Germany
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8
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Chelbi-Alix MK, Brouard A, Boissard C, Pelaprat D, Rostene W, Thang MN. Induction by vasoactive intestinal peptide of interferon alpha/beta synthesis in glial cells but not in neurons. J Cell Physiol 1994; 158:47-54. [PMID: 7505279 DOI: 10.1002/jcp.1041580107] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Vasoactive intestinal peptide (VIP), a 28-amino acid peptide, plays a multifunctional neuromodulatory role in both peripheral and central nervous systems. We have recently reported that VIP induces interferon (IFN) alpha/beta synthesis in human colon adenocarcinoma cell line HT-29. It has been reported that VIP may counteract HIV-induced neuronal cell death; therefore, we postulated that the action of VIP may be mediated by a cascade regulation, involving the production of some cytokines such as IFN. Here we demonstrate that primary cultures of rat mesencephalic neurons and glial cells respond differently to VIP. Thus VIP enhanced 2'5' oligoadenylate (2'5' A) synthetase activity and inhibited vesicular stomatitis virus multiplication in glial cultures only. However, both cell cultures had functional adenylate cyclase coupled receptors for VIP. The increase in 2'5'A synthetase activity in glial cultures reached a maximum with 10(-6) M VIP and required cellular RNA and protein synthesis. Anti-IFN alpha/beta, but not anti-IFN gamma, antibodies abolished the induction of the antiviral and 2'5'A synthetase activities by VIP in rat glial-enriched cultures, suggesting that these inductions were mediated through IFN alpha/beta synthesis. Moreover, VIP or poly (i). poly (C12U) caused, in the glial cultures, the induction and secretion of an IFN of type alpha/beta with a titer value of 16 and 32 units/ml respectively. In contrast, neither of these two substances was able to induce IFN synthesis in neurons, which were, however, sensitive to IFN alpha/beta produced by VIP-treated glial cells. IFN produced by VIP in glial cells may therefore play an important role in defending the brain against viruses.
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Affiliation(s)
- M K Chelbi-Alix
- Institut National de la Santé et de la Recherche Médicale Unité 245, Hôpital St-Antoine, Paris, France
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9
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Itkes AV. Oligoadenylate and cyclic AMP: interrelation and mutual regulation. PROGRESS IN MOLECULAR AND SUBCELLULAR BIOLOGY 1994; 14:209-21. [PMID: 7520328 DOI: 10.1007/978-3-642-78549-8_12] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The data obtained are in good agreement with the hypothesis that cAMP is involved in the control of 2-5A metabolism, including the mediation of the regulation of 2-5A by IFNs; 2-5A, in turn, affects the intracellular cAMP level. The general question originating from the data is that of a biochemical mechanism connecting the activation of the cAMP/2-5A system and the effect of depression of cell division. In my opinion, this universal effect is the result of the action of the known 2-5A-dependent mechanism, namely, RNase L (see review by Pestka et al. 1987), rather than by any new 2-5A-stimulating enzyme. The RNase L activated by 2-5A decreases the total level of protein synthesis and accelerates the degradation of cellular RNA, resulting in the inhibition of cell growth. It should be mentioned that such activation of RNA turnover is generally characteristic for nondividing cells, especially for cells in the resting state (Epifanova et al. 1983). Thus, the regulatory system of cAMP/2-5A is involved evidently in the antiproliferative mechanism characteristic for the resting cells, controlling the variations in the levels of RNA turnover and protein synthesis.
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Affiliation(s)
- A V Itkes
- Institute of Molecular Biology, Academy of Sciences of Russia, Moscow
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10
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Landolfo S, Gariglio M, Gribaudo G, Garotta G. Double-stranded RNAs as gene activators. PROGRESS IN MOLECULAR AND SUBCELLULAR BIOLOGY 1994; 14:15-27. [PMID: 8061883 DOI: 10.1007/978-3-642-78549-8_2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- S Landolfo
- Institute of Microbiology, Medical School, University of Torino, Italy
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11
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Bourgeade MF, Laurent-Winter C, Besançon F, Thang MN, Mémet S. Differential kinetics of polypeptide expression and different biological activities in the human fibroblast response to dsRNA or interferon treatment. JOURNAL OF INTERFERON RESEARCH 1993; 13:175-86. [PMID: 8396164 DOI: 10.1089/jir.1993.13.175] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Using two-dimensional electrophoresis on total and nuclear extracts of human fibroblasts, we compared polypeptide patterns of cells treated with interferon-beta (IFN-beta), IFN-gamma, or with dsRNA in the presence of anti-IFN antibodies. The analysis of whole-cell extracts revealed that, after a 6-h treatment, the three agents induce the synthesis of a common set of proteins in addition to others that are specifically induced either by IFNs or by dsRNA. After a 15-h treatment, this common set of proteins was only induced by IFNs. Furthermore, at this time, IFNs also regulated proteins whose synthesis was specifically induced or repressed by poly(I).poly(C) in the 6-h treated cells. These results indicate that poly(I).poly(C) regulates protein expression more rapidly and more transiently than IFNs. The analysis of nuclear extracts showed similar differential kinetics of protein expression. However, a greater number of polypeptides was found to have their synthesis specifically induced by dsRNA. Moreover, poly(I).poly(C) was found to be mitogenic in these cells and did not induce a significant resistance to vesicular stomatitis virus (VSV). This study provides evidence for an overlap in the expression of proteins by dsRNA and IFNs, although these compounds do not share the same biological activities.
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12
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Ushijima H, Rytik PG, Schäcke H, Scheffer U, Müller WE, Schröder HC. Mode of action of the anti-AIDS compound poly(I).poly(C12U) (Ampligen): activator of 2',5'-oligoadenylate synthetase and double-stranded RNA-dependent kinase. JOURNAL OF INTERFERON RESEARCH 1993; 13:161-71. [PMID: 8099601 DOI: 10.1089/jir.1993.13.161] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The mismatched double-stranded RNA (dsRNA), poly(I).poly(C12U), also termed Ampligen, exhibits a strong antiviral and cytoprotective effect on cells (human T-lymphoblastoid CEM cells and human T-cell line H9) infected with the human immunodeficiency virus type 1 (HIV-1). Untreated H9 cells infected with HIV-1 start to release the virus 3 days post-infection, while in the presence of 40 micrograms/ml (80 micrograms/ml) of poly(I).poly(C12U) the onset of virus production and release is retarded and does not occur before day 5 (day 6). We demonstrate that poly(I).poly(C12U) markedly extends the duration of the transient increase of 2',5'-oligoadenylate (2-5A) synthetase mRNA level and activity preceding virus production after infection of cells with HIV-1. Treatment of HeLa cells with poly(I).poly(C12U) was found to cause a significant increase in total (activated plus latent) 2-5A synthetase activity; no evidence was obtained that the level of latent (nonactivated) 2-5A synthetase is changed in cells treated with dsRNA plus interferon (IFN). Poly(I).poly(C12U) is able to bind and to activate 2-5A synthetase(s) from HeLa cell extracts. Addition of poly(I).poly(C12U) to HeLa cell extracts results in production of longer 2-5A oligomers (> or = 3 adenylate residues), which are better activators of RNase L. Both free and immobilized poly(I).poly(C12U) also bind to the dsRNA-dependent protein kinase (p68 kinase), resulting in autophosphorylation of the enzyme. Activation of the kinase by the free RNA occurs within a limited concentration range (10(-7) to 10(-6) grams/ml). Addition of HIV-1 Tat protein does not affect binding and activation of p68 kinase to poly(I).poly(C12U)-cellulose but strongly reduces the binding of the kinase to immobilized TAR RNA of HIV-1. We conclude that poly(I).poly(C12U) may antagonize Tat-mediated down-regulation of dsRNA-dependent enzymes.
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Affiliation(s)
- H Ushijima
- Division of AIDS Virus, AIDS Research Center, National Institute of Health, Tokyo, Japan
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13
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Garfinkel S, Haines D, Brown S, Wessendorf J, Gillespie D, Maciag T. Interleukin-1 alpha mediates an alternative pathway for the antiproliferative action of poly(I.C) on human endothelial cells. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(18)35776-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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14
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Du W, Maniatis T. An ATF/CREB binding site is required for virus induction of the human interferon beta gene [corrected]. Proc Natl Acad Sci U S A 1992; 89:2150-4. [PMID: 1532252 PMCID: PMC48614 DOI: 10.1073/pnas.89.6.2150] [Citation(s) in RCA: 92] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
We report the characterization of a distinct regulatory element of the human interferon beta (HuIFN-beta) gene promoter, which we designate PRDIV (positive regulatory domain IV). In previous studies, sequences between -104 and -91 base pairs upstream from the start site of transcription were shown to be required for maximal levels of virus induction in mouse L929 cells. We have localized the essential sequence in this region extending from -99 to at least -91, and we show that this sequence is a binding site for a protein of the activating transcription factor/cAMP response element binding protein (ATF/CREB) family of transcription factors. Mutations in PRDIV that decrease the affinity of one member of this family (ATF-2/CRE-BP1) decrease the level of virus induction in vivo. Moreover, multiple copies of PRDIV can confer both virus and cAMP inducibility upon a minimal promoter in L929 cells, while it is constitutively active in HeLa cells. We conclude that PRDIV is a distinct regulatory element of the HuIFN-beta promoter and that the signal transduction pathways involved in virus and cAMP induction may partially overlap.
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Affiliation(s)
- W Du
- Department of Biochemistry and Molecular Biology, Harvard University, Cambridge, MA 02138
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15
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Abstract
Ampligen, a mismatched double stranded RNA, is hypothesized to be an ideal base therapy for HIV disease to which other agents, such as the nucleoside analogue, AZT, can be advantageously added. The unique properties of Ampligen which support this hypothesis include activation of immune cells, inhibition of virus replication by inducing an antiviral cellular state and inhibition of growth of neoplastic cells. Ampligen is synergistic with other agents being used or being tested for use in HIV disease and is without toxicity.
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Affiliation(s)
- D Gillespie
- Department of Neoplastic Diseases, Hahnemann University, Philadelphia, PA 19102
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Hubbell HR, Gibson GD, Bigler RD. Potentiated lymphokine-activated killer cell activity generated by low-dose interleukin-2 and mismatched double-stranded RNA. Cancer Immunol Immunother 1992; 34:259-64. [PMID: 1537057 PMCID: PMC11038620 DOI: 10.1007/bf01741794] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/1991] [Accepted: 09/09/1991] [Indexed: 12/27/2022]
Abstract
Lymphokine-activated killer (LAK) cell activity was measured in human peripheral blood mononuclear cells (PBMC) treated in vitro for 3 days with recombinant interleukin-2 (rIL-2) and mismatched double-stranded RNA (dsRNA). Lytic activity was measured utilizing K562 (NK-sensitive) and 786-0 (NK-resistant) target cells. PBMC cultured with rIL-2 (10-1000 BRMP U/ml) alone showed concentration-dependent lytic activity against the 786-0 target cells, while cells cultured in unsupplemented medium or medium supplemented with mismatched dsRNA (200 micrograms/ml) alone could not lyse the 786-0 targets. The combination of mismatched dsRNA with suboptimal concentrations of rIL-2 (10-30 U/ml) showed enhancement of both natural killer (NK) and LAK cell activities. The uptake of [3H]thymidine by treated effector cells was dependent on time and rIL-2 concentration and was not increased in the cells treated with low-dose rIL-2/mismatched dsRNA, compared to those treated with low-dose rIL-2 or mismatched dsRNA alone. Similarly, changes in the expression of CD3, CD4, CD8, CD57, CD16 and CD25 cell surface antigens were independent or rIL-2 concentration and not altered by the presence of mismatched dsRNA. These results indicate that mismatched dsRNA can potentiate rIL-2-induced LAK cell activity by increasing the functional activity per cell, rather than by increasing the number of activated cells.
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Affiliation(s)
- H R Hubbell
- Department of Neoplastic Diseases, Hahnemann University, Philadelphia, Pennsylvania 19102
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18
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Abstract
The study of double-stranded RNA (dsRNA) encompasses a variety of fields. Basic research in this area has contributed to a greater mechanistic understanding of gene induction, tumor cell growth arrest, the establishment of antiviral states, and immunomodulation. Because of the possible clinical value of these molecules, physicians are now exploring the use of synthetic dsRNA to treat patients with cancer, HIV-1 disease, and immune dysfunction. Continued studies of the mechanisms of action of dsRNA are likely to suggest an even wider scope of clinical applications.
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Affiliation(s)
- D S Haines
- Department of Neoplastic Diseases, Hahnemann University, Philadelphia, Pennsylvania 19102
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