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Jansons J, Sominskaya I, Petrakova N, Starodubova ES, Smirnova OA, Alekseeva E, Bruvere R, Eliseeva O, Skrastina D, Kashuba E, Mihailova M, Kochetkov SN, Ivanov AV, Isaguliants MG. The Immunogenicity in Mice of HCV Core Delivered as DNA Is Modulated by Its Capacity to Induce Oxidative Stress and Oxidative Stress Response. Cells 2019; 8:cells8030208. [PMID: 30823485 PMCID: PMC6468923 DOI: 10.3390/cells8030208] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 02/06/2019] [Accepted: 02/20/2019] [Indexed: 12/16/2022] Open
Abstract
HCV core is an attractive HCV vaccine target, however, clinical or preclinical trials of core-based vaccines showed little success. We aimed to delineate what restricts its immunogenicity and improve immunogenic performance in mice. We designed plasmids encoding full-length HCV 1b core and its variants truncated after amino acids (aa) 60, 98, 152, 173, or up to aa 36 using virus-derived or synthetic polynucleotides (core191/60/98/152/173/36_191v or core152s DNA, respectively). We assessed their level of expression, route of degradation, ability to trigger the production of reactive oxygen species/ROS, and to activate the components of the Nrf2/ARE antioxidant defense pathway heme oxygenase 1/HO-1 and NAD(P)H: quinone oxidoreductase/Nqo-1. All core variants with the intact N-terminus induced production of ROS, and up-regulated expression of HO-1 and Nqo-1. The capacity of core variants to induce ROS and up-regulate HO-1 and Nqo-1 expression predetermined their immunogenicity in DNA-immunized BALB/c and C57BL/6 mice. The most immunogenic was core 152s, expressed at a modest level and inducing moderate oxidative stress and oxidative stress response. Thus, immunogenicity of HCV core is shaped by its ability to induce ROS and oxidative stress response. These considerations are important in understanding the mechanisms of viral suppression of cellular immune response and in HCV vaccine design.
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Affiliation(s)
- Juris Jansons
- Department of Pathology, Riga Stradins University, LV-1007 Riga, Latvia.
- Latvian Biomedical Research and Study Centre, LV-1067 Riga, Latvia.
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, SE-171 77 Stockholm, Sweden.
| | - Irina Sominskaya
- Latvian Biomedical Research and Study Centre, LV-1067 Riga, Latvia.
| | - Natalia Petrakova
- N.F. Gamaleya Research Center of Epidemiology and Microbiology, Ministry of Health of the Russian Federation, 123098 Moscow, Russia.
| | - Elizaveta S Starodubova
- N.F. Gamaleya Research Center of Epidemiology and Microbiology, Ministry of Health of the Russian Federation, 123098 Moscow, Russia.
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia.
| | - Olga A Smirnova
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia.
| | - Ekaterina Alekseeva
- Department of Pathology, Riga Stradins University, LV-1007 Riga, Latvia.
- Latvian Biomedical Research and Study Centre, LV-1067 Riga, Latvia.
| | - Ruta Bruvere
- Latvian Biomedical Research and Study Centre, LV-1067 Riga, Latvia.
| | - Olesja Eliseeva
- N.F. Gamaleya Research Center of Epidemiology and Microbiology, Ministry of Health of the Russian Federation, 123098 Moscow, Russia.
| | - Dace Skrastina
- Department of Pathology, Riga Stradins University, LV-1007 Riga, Latvia.
- Latvian Biomedical Research and Study Centre, LV-1067 Riga, Latvia.
| | - Elena Kashuba
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, SE-171 77 Stockholm, Sweden.
- RE Kavetsky Institite of Experimental Pathology, Oncology and Radiobiology, The National Academy of Sciences of Ukraine, 03022 Kyiv, Ukraine.
| | - Marija Mihailova
- Latvian Biomedical Research and Study Centre, LV-1067 Riga, Latvia.
| | - Sergey N Kochetkov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia.
| | - Alexander V Ivanov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia.
| | - Maria G Isaguliants
- Department of Pathology, Riga Stradins University, LV-1007 Riga, Latvia.
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, SE-171 77 Stockholm, Sweden.
- N.F. Gamaleya Research Center of Epidemiology and Microbiology, Ministry of Health of the Russian Federation, 123098 Moscow, Russia.
- MP Chumakov Center for Research and Development of Immune and Biological Preparations of RAS, 108819 Moscow, Russia.
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Niedre-Otomere B, Bogdanova A, Bruvere R, Ose V, Gerlich WH, Pumpens P, Glebe D, Kozlovska T. Posttranslational modifications and secretion efficiency of immunogenic hepatitis B virus L protein deletion variants. Virol J 2013; 10:63. [PMID: 23442390 PMCID: PMC3598826 DOI: 10.1186/1743-422x-10-63] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Accepted: 02/20/2013] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Subviral particles of hepatitis B virus (HBV) composed of L protein deletion variants with the 48 N-terminal amino acids of preS joined to the N-terminus of S protein (1-48preS/S) induced broadly neutralizing antibodies after immunization of mice with a Semliki Forest virus vector. A practical limitation for use as vaccine is the suboptimal secretion of such particles. The role of the N-terminal preS myristoylation in the cellular retention of full-length L protein is described controversially in the literature and the relation of these data to the truncated L protein was unknown. Thus, we studied the effect of preS myristoylation signal suppression on 1-48preS/S secretion efficiency, glycosylation and subcellular distribution. FINDINGS The findings are that 1-48preS/S is secreted, and that removal of the N-terminal myristoylation signal in its G2A variant reduced secretion slightly, but significantly. The glycosylation pattern of 1-48preS/S was not affected by the removal of the myristoylation signal (G2A mutant) but was different than natural L protein, whereby N4 of the preS and N3 of the S domain were ectopically glycosylated. This suggested cotranslational translocation of 1-48preS in contrast to natural L protein. The 1-48preS/S bearing a myristoylation signal was localized in a compact, perinuclear pattern with strong colocalization of preS and S epitopes, while the non-myristoylated mutants demonstrated a dispersed, granular cytoplasmic distribution with weaker colocalization. CONCLUSIONS The large deletion in 1-48preS/S in presence of the myristoylation site facilitated formation and secretion of protein particles with neutralizing preS1 epitopes at their surface and could be a useful feature for future hepatitis B vaccines.
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Niedre-Otomere B, Bogdanova A, Skrastina D, Zajakina A, Bruvere R, Ose V, Gerlich WH, Garoff H, Pumpens P, Glebe D, Kozlovska T. Recombinant Semliki Forest virus vectors encoding hepatitis B virus small surface and pre-S1 antigens induce broadly reactive neutralizing antibodies. J Viral Hepat 2012; 19:664-73. [PMID: 22863271 DOI: 10.1111/j.1365-2893.2012.01594.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Most hepatitis B virus (HBV) vaccines consist of viral small surface (S) protein subtype adw2 expressed in yeast cells. In spite of good efficacy, HBV-genotype and subtype differences, escape mutants and insufficient Th1 activation remain potential problems. To address these problems, we generated recombinant Semliki Forest virus (rSFV) vectors encoding S protein, subtype adw2 or ayw2, or a fragment of the large surface protein, amino acids 1-48 of the pre-S1 domain, fused to S (pre-S1.1-48/S). The antigen loop in S protein and the selected pre-S1 sequences are known targets of neutralizing antibodies. BALB/c mice were immunized intravenously with 10(7) rSFV particles and 10(8) rSFV particles 3 weeks later. Antibodies induced by rSFV encoding S proteins reacted preferentially with subtype determinants of yeast-derived S antigen but equally well with patient-derived S antigen. Immunization with rSFV encoding pre-S1.1-48/S resulted in formation of pre-S1- and S-specific immunoglobulin G (IgG), while immunization with the isogenic mutant without S start codon induced pre-S1 antibodies only. Neutralizing antibodies were determined by mixing with plasma-derived HBV/ayw2 and subsequent inoculation of susceptible primary hepatocyte cultures from Tupaia belangeri. S/adw2 antisera neutralized HBV/ayw2 as effectively as antisera raised with S/ayw2. The pre-S1 antibodies also completely neutralized HBV infectivity. The IgG1/IgG2a ratios ranged from 0.28 to 0.88 in the four immunized groups and were lowest for the pre-S1.1-48/S vector, indicating the strongest Th1 response. This vector type may induce subtype-independent and S-escape-resistant neutralizing antibodies against HBV.
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Affiliation(s)
- B Niedre-Otomere
- Biomedical Research and Study Centre, University of Latvia, Riga, Latvia, Germany
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Ranka R, Petrovskis I, Sominskaya I, Bogans J, Bruvere R, Akopjana I, Ose V, Timofejeva I, Brangulis K, Pumpens P, Baumanis V. Fibronectin-binding nanoparticles for intracellular targeting addressed by B. burgdorferi BBK32 protein fragments. Nanomedicine 2012; 9:65-73. [PMID: 22633898 DOI: 10.1016/j.nano.2012.05.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2011] [Revised: 04/17/2012] [Accepted: 05/02/2012] [Indexed: 11/30/2022]
Abstract
UNLABELLED Virus-like particles (VLPs) are created by the self-assembly of multiple copies of envelope and/or capsid proteins from many viruses, mimicking the conformation of a native virus. Such noninfectious nanostructures are mainly used as antigen-presenting platforms, especially in vaccine research; however, some of them recently were used as scaffolds in biotechnology to produce targeted nanoparticles for intracellular delivery. This study demonstrates the creation of fusion VLPs using hepatitis B core protein-based system maintaining a fibronectin-binding property from B. burgdorferi BBK32 protein, including the evidence of particles' transmission to BHK-21 target cells via caveolae/rafts endocythosis. These results make this construct to be an attractive model in development of HBc-based nanoparticles for cellular targeting applications and highlights the fragment of B. burgdorferi BBK32 as a novel cellular uptake-promoting peptide. FROM THE CLINICAL EDITOR This paper discusses the nanotechnology-based application of self-assembling viral-like peptides (VLP-s) for targeted delivery using a hepatitis B core protein based system. Creating fusion VLPs may be an attractive model for cellular targeting applications.
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Affiliation(s)
- Renate Ranka
- Latvian Biomedical Research and Study Centre, Riga, Latvia.
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Kalnina I, Bruvere R, Zvagule T, Gabruseva N, Klimkane L, Kirilova E, Meirovics I, Kizane G. Fluorescent Probe ABM and Estimation of Immune State in Patients with Different Pathologies (Review Article). J Fluoresc 2009; 20:9-17. [DOI: 10.1007/s10895-009-0515-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2009] [Accepted: 06/29/2009] [Indexed: 11/30/2022]
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Alekseeva E, Sominskaya I, Skrastina D, Egorova I, Starodubova E, Kushners E, Mihailova M, Petrakova N, Bruvere R, Kozlovskaya T, Isaguliants M, Pumpens P. Enhancement of the expression of HCV core gene does not enhance core-specific immune response in DNA immunization: advantages of the heterologous DNA prime, protein boost immunization regimen. Genet Vaccines Ther 2009; 7:7. [PMID: 19505299 PMCID: PMC2702340 DOI: 10.1186/1479-0556-7-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2008] [Accepted: 06/08/2009] [Indexed: 01/17/2023]
Abstract
BACKGROUND Hepatitis C core protein is an attractive target for HCV vaccine aimed to exterminate HCV infected cells. However, although highly immunogenic in natural infection, core appears to have low immunogenicity in experimental settings. We aimed to design an HCV vaccine prototype based on core, and devise immunization regimens that would lead to potent anti-core immune responses which circumvent the immunogenicity limitations earlier observed. METHODS Plasmids encoding core with no translation initiation signal (pCMVcore); with Kozak sequence (pCMVcoreKozak); and with HCV IRES (pCMVcoreIRES) were designed and expressed in a variety of eukaryotic cells. Polyproteins corresponding to HCV 1b amino acids (aa) 1-98 and 1-173 were expressed in E. coli. C57BL/6 mice were immunized with four 25-microg doses of pCMVcoreKozak, or pCMV (I). BALB/c mice were immunized with 100 microg of either pCMVcore, or pCMVcoreKozak, or pCMVcoreIRES, or empty pCMV (II). Lastly, BALB/c mice were immunized with 20 microg of core aa 1-98 in prime and boost, or with 100 microg of pCMVcoreKozak in prime and 20 microg of core aa 1-98 in boost (III). Antibody response, [3H]-T-incorporation, and cytokine secretion by core/core peptide-stimulated splenocytes were assessed after each immunization. RESULTS Plasmids differed in core-expression capacity: mouse fibroblasts transfected with pCMVcore, pCMVcoreIRES and pCMVcoreKozak expressed 0.22 +/- 0.18, 0.83 +/- 0.5, and 13 +/- 5 ng core per cell, respectively. Single immunization with highly expressing pCMVcoreKozak induced specific IFN-gamma and IL-2, and weak antibody response. Single immunization with plasmids directing low levels of core expression induced similar levels of cytokines, strong T-cell proliferation (pCMVcoreIRES), and antibodies in titer 103(pCMVcore). Boosting with pCMVcoreKozak induced low antibody response, core-specific T-cell proliferation and IFN-gamma secretion that subsided after the 3rd plasmid injection. The latter also led to a decrease in specific IL-2 secretion. The best was the heterologous pCMVcoreKozak prime/protein boost regiment that generated mixed Th1/Th2-cellular response with core-specific antibodies in titer >or= 3 x 10(3). CONCLUSION Thus, administration of highly expressed HCV core gene, as one large dose or repeated injections of smaller doses, may suppress core-specific immune response. Instead, the latter is induced by a heterologous DNA prime/protein boost regiment that circumvents the negative effects of intracellular core expression.
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Affiliation(s)
- Ekaterina Alekseeva
- Latvian Biomedical Research and Study Centre, Ratsupites 1, Riga, LV-1067, Latvia.
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Kalnina Z, Silina K, Bruvere R, Gabruseva N, Stengrevics A, Barnikol-Watanabe S, Leja M, Line A. Molecular characterisation and expression analysis of SEREX-defined antigen NUCB2 in gastric epithelium, gastritis and gastric cancer. Eur J Histochem 2009; 53:7-18. [PMID: 19351608 DOI: 10.4081/ejh.2009.7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
NUCB2 is an EF-hand Ca2+ binding protein that has been implicated in various physiological processes like calcium homeostasis, hypothalamic regulation of feeding and TNF receptor shedding. In our previous study we identified NUCB2 as a potential tumour antigen eliciting autoantibody responses in 5.4% of gastric cancer patients but not in the healthy individuals.The current study aimed to elucidate the molecular mechanism underlying NUCB2 immunogenicity and to gain an insight into the physiological functions of NUCB2 in the stomach. mRNA expression analysis demonstrated that NUCB2 is ubiquitously expressed in normal tissues, including lymphoid tissues, and downregulated in gastric tumours when compared with the adjacent relatively normal stomach tissues.The search for molecular alterations resulted in the identification of novel mRNA variants transcribed from an alternative promoter and expressed predominantly in gastric cancers. Western blot analysis demonstrated that the protein levels correspond to mRNA levels and revealed that NUCB2 is phosphorylated in gastric mucosa. Furthermore, a 55 kDa isoform,generated presumably by yet an unidentified post-translational modification was detected in gastric tumours and AGS gastric cancer cells but was absent in the relatively normal gastric mucosa and thereby might have served as a trigger for the immune response against NUCB2. Staining of stomach tissue microarray with anti-NUCB2 antibody revealed that it is expressed in the secretory granules of chief cells and in the cytoplasm of parietal cells in the functioning gastric glands which are lost in atrophic glands and tumour cells. Hence we propose that NUCB2 may be implicated in gastric secretion by establishing an agonist-releasable Ca2+ store in ER or Golgi apparatus, signalling via heterotrimeric Galpha proteins and/or mediating the exocytosis of the secretory granules.
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Affiliation(s)
- Zane Kalnina
- Latvian Biomedical Research and Study Centre, Riga, Latvia.
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Kalnina Z, Silina K, Bruvere R, Gabruseva N, Stengrevics A, Barnikol-Watanabe S, Leja M, Line A. Molecular characterisation and expression analysis of SEREX-defined antigen NUCB2 in gastric epithelium, gastritis and gastric cancer. Eur J Histochem 2009; 53:e2. [PMID: 30256860 PMCID: PMC3167273 DOI: 10.4081/ejh.2009.e2] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/24/2008] [Indexed: 11/23/2022] Open
Abstract
NUCB2 is an EF-hand Ca2+ binding protein that has been implicated in various physiological processes like calcium homeostasis, hypothalamic regulation of feeding and TNF receptor shedding. In our previous study we identified NUCB2 as a potential tumour antigen eliciting autoantibody responses in 5.4% of gastric cancer patients but not in the healthy individuals. The current study aimed to elucidate the molecular mechanism underlying NUCB2 immunogenicity and to gain an insight into the physiological functions of NUCB2 in the stomach. mRNA expression analysis demonstrated that NUCB2 is ubiquitously expressed in normal tissues, including lymphoid tissues, and downregulated in gastric tumours when compared with the adjacent relatively normal stomach tissues. The search for molecular alterations resulted in the identification of novel mRNA variants transcribed from an alternative promoter and expressed predominantly in gastric cancers. Western blot analysis demonstrated that the protein levels correspond to mRNA levels and revealed that NUCB2 is phosphorylated in gastric mucosa. Furthermore, a 55 kDa isoform, generated presumably by yet an unidentified post-translational modification was detected in gastric tumours and AGS gastric cancer cells but was absent in the relatively normal gastric mucosa and thereby might have served as a trigger for the immune response against NUCB2. Staining of stomach tissue microarray with anti-NUCB2 antibody revealed that it is expressed in the secretory granules of chief cells and in the cytoplasm of parietal cells in the functioning gastric glands which are lost in atrophic glands and tumour cells. Hence we propose that NUCB2 may be implicated in gastric secretion by establishing an agonist-releasable Ca2+ store in ER or Golgi apparatus, signalling via heterotrimeric Gα proteins and/or mediating the exocytosis of the secretory granules.
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Affiliation(s)
- Z Kalnina
- Latvian Biomedical Research and Study Centre, Riga, Latvia
| | - K Silina
- Latvian Biomedical Research and Study Centre, Riga, Latvia
| | - R Bruvere
- Latvian Biomedical Research and Study Centre, Riga, Latvia
| | - N Gabruseva
- Latvian Biomedical Research and Study Centre, Riga, Latvia
| | | | - S Barnikol-Watanabe
- Department of Immunochemistry, Max Planck Institute for Experimental Medicine, Göttingen, Germany
| | - M Leja
- Faculty of Medicine, University of Latvia, Riga, Latvia
| | - A Line
- Latvian Biomedical Research and Study Centre, Riga, Latvia
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Braun S, Zajakina A, Aleksejeva J, Sharipo A, Bruvere R, Ose V, Pumpens P, Garoff H, Meisel H, Kozlovska T. Proteasomal degradation of core protein variants from chronic hepatitis B patients. J Med Virol 2007; 79:1312-21. [PMID: 17607782 DOI: 10.1002/jmv.20939] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [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: 12/29/2022]
Abstract
The accumulation of complex hepatitis B virus (HBV) variants with internal in-frame deletions in the C gene in immunosuppressed renal transplant recipients is associated with a severe course of the infection leading to end-stage liver disease (ESLD). A set of six HBV C genes with internal in-frame deletions corresponding to the pattern of HBV population in immunosuppressed patients has been expressed in two different eukaryotic cell lines. Synthesis and proteasomal degradation of HBV core (HBc) protein variants were compared with those of the wild-type HBc. In all cases, the steady-state level of internally deleted HBc proteins, predominantly with longer deletions, were considerably lower and turnover was significantly higher in comparison with those of the wild-type HBc, since all deletion variants were degraded rapidly via the proteasome pathway. Involvement and consequences of the proteasomal degradation machinery in the HBc protein turnover during HBV infection with complex HBV variants in the immunosuppressed patients are discussed.
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Affiliation(s)
- Sabine Braun
- Universitätsmedizin Berlin, Charité, Institut für Virologie, Campus Mitte, Charitéplatz 1, Berlin, Germany
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Zajakina A, Kozlovska T, Bruvere R, Aleksejeva J, Pumpens P, Garoff H. Translation of hepatitis B virus (HBV) surface proteins from the HBV pregenome and precore RNAs in Semliki Forest virus-driven expression. J Gen Virol 2004; 85:3343-3351. [PMID: 15483250 DOI: 10.1099/vir.0.80388-0] [Citation(s) in RCA: 8] [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: 11/18/2022] Open
Abstract
Hepatitis B virus (HBV) pregenome RNA (pgRNA) serves as a translation template for the HBV core (HBc) protein and viral polymerase (Pol). HBV precore RNA (pcRNA) directs the synthesis of the precore (preC) protein, a precursor of the hepatitis B e antigen (HBeAg). pgRNA and pcRNA were expressed in the Semliki Forest virus (SFV) expression system. Besides the HBc and preC proteins, there was revealed the synthesis of all three forms of HBV surface (HBs) proteins: long (LHBs), middle (MHBs) and short (SHBs), the start codons of which are located more than 1000 nt downstream of the HBc and preC start codons. Moreover, other HBV templates, such as 3′-truncated pgRNA lacking 3′ direct repeat and Pol mRNA, both carrying internally the HBs sequences, provided the synthesis of three HBs protein forms in the SFV-driven expression system. Maximal production of the HBs was provided by Pol mRNA, while HBc- and preC-producing templates showed relatively low internal translation of the HBs. These data allow the proposal of a ribosome leaky scanning model of internal translation initiation for HBs proteins. The putative functional role of such exceptional synthesis of the HBs proteins from the pgRNA and pcRNA templates in the natural HBV infection process needs further evaluation.
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Affiliation(s)
- Anna Zajakina
- Department of Protein Engineering, Biomedical Research and Study Centre, University of Latvia, Ratsupites Str., 1, LV-1067 Riga, Latvia
| | - Tatyana Kozlovska
- Department of Protein Engineering, Biomedical Research and Study Centre, University of Latvia, Ratsupites Str., 1, LV-1067 Riga, Latvia
| | - Ruta Bruvere
- Department of Protein Engineering, Biomedical Research and Study Centre, University of Latvia, Ratsupites Str., 1, LV-1067 Riga, Latvia
| | - Jekaterina Aleksejeva
- Department of Protein Engineering, Biomedical Research and Study Centre, University of Latvia, Ratsupites Str., 1, LV-1067 Riga, Latvia
| | - Paul Pumpens
- Department of Protein Engineering, Biomedical Research and Study Centre, University of Latvia, Ratsupites Str., 1, LV-1067 Riga, Latvia
| | - Henrik Garoff
- Department of Biosciences at Novum, Karolinska Institute, S-141 57 Huddinge, Sweden
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Kurjane N, Bruvere R, Shitova O, Romanova T, Jaunalksne I, Kirschfink M, Sochnevs A. Analysis of the immune status in Latvian Chernobyl clean-up workers with nononcological thyroid diseases. Scand J Immunol 2001; 54:528-33. [PMID: 11696206 DOI: 10.1046/j.1365-3083.2001.00997.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [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: 11/20/2022]
Abstract
The aim of the present work was to characterize the immune status of 385 individuals who participated in the 1986-90 clean-up work of the after effects of the Chernobyl nuclear power plant explosion. Fifty-nine Chernobyl clean-up workers developed the most common thyroid diseases; euthyroid nodular and diffuse goiter; 47 healthy blood donors were taken as controls. The levels of immunoglobulins (IgA, IgG and IgM), the numbers of peripheral blood leukocytes, lymphocytes, monocytes, T lymphocytes and their subpopulations (CD3+, CD4+, CD8+), B lymphocytes (CD19+), natural killer (NK) cells (CD16+), classical and alternative pathway activity of complement (CH50, APH50), the C3 split product C3d, and neutrophil phagocytosis were determined in the peripheral blood. We found a significantly decreased number of CD16+ cells (natural killer), of CD4+ and CD8+ T lymphocytes, a reduced neutrophil phagocytic activity as well as a significant complement activation in Chernobyl clean-up workers with and without thyroid diseases when compared with normal levels and those in the control group. In addition, the number of CD3+ and CD4+ cells was significantly higher in patients with nodular goiter when compared with that in patients with diffuse goiter. Levels of IgG and numbers of monocytes were significantly decreased in persons who worked in Chernobyl in 1986 during the first 2 months after the accident (with maximal radiation exposure) but were without correlation to thyroid disorders. Our results clearly reflect an impaired immune system in the Chernobyl clean-up workers even 10-14 years after the nuclear accident.
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Affiliation(s)
- N Kurjane
- Institute of Immunology, Rigas Stradina University, Dzirciema 16, Riga LV-1007, Latvia.
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12
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Mironova-Ulmane N, Pavlenko A, Zvagule T, Kärner T, Bruvere R, Volrate A. Retrospective dosimetry for Latvian workers at Chernobyl. Radiat Prot Dosimetry 2001; 96:237-240. [PMID: 11586739 DOI: 10.1093/oxfordjournals.rpd.a006591] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Between 1986 and 1991 approximately 6500 Latvian inhabitants were recruited for clean-up work at the Chernobyl nuclear power plant. Their absorbed doses are usually unknown, because less than half of them had their external exposure officially documented. Clinical investigations show a high morbidity rate for these clean-up workers when compared with that of the general population. In order to understand the causes of their diseases and the impact of ionising radiation, electron spin resonance (ESR) has been used to measure the absorbed doses in human tooth enamel. The doses estimated by ESR were between two and three times higher than previously documented and are in accord with the results of immunological and biological tests. The results may be explained by considering the effects of irradiation caused by long-lived incorporated radionuclides.
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Affiliation(s)
- N Mironova-Ulmane
- Institute of Solid States Physics, University of Latvia, 31 Miera St, Salaspils, LV-2169, Latvia.
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