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Ackermann-Gäumann R, Lang P, Zens KD. Defining the "Correlate(s) of Protection" to tick-borne encephalitis vaccination and infection - key points and outstanding questions. Front Immunol 2024; 15:1352720. [PMID: 38318179 PMCID: PMC10840404 DOI: 10.3389/fimmu.2024.1352720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Accepted: 01/05/2024] [Indexed: 02/07/2024] Open
Abstract
Tick-borne Encephalitis (TBE) is a severe disease of the Central Nervous System (CNS) caused by the tick-borne encephalitis virus (TBEV). The generation of protective immunity after TBEV infection or TBE vaccination relies on the integrated responses of many distinct cell types at distinct physical locations. While long-lasting memory immune responses, in particular, form the basis for the correlates of protection against many diseases, these correlates of protection have not yet been clearly defined for TBE. This review addresses the immune control of TBEV infection and responses to TBE vaccination. Potential correlates of protection and the durability of protection against disease are discussed, along with outstanding questions in the field and possible areas for future research.
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Affiliation(s)
- Rahel Ackermann-Gäumann
- Microbiologie, ADMED Analyses et Diagnostics Médicaux, La Chaux-de-Fonds, Switzerland
- Swiss National Reference Center for Tick-transmitted Diseases, La Chaux-de-Fonds, Switzerland
| | - Phung Lang
- Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Zurich, Switzerland
| | - Kyra D. Zens
- Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Zurich, Switzerland
- Institute for Experimental Immunology, University of Zurich, Zurich, Switzerland
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Ackermann-Gäumann R, Brêchet A, Smetana J, Salát J, Lienhard R, Croxatto A, Polcarová P, Chlíbek R, Růžek D. Vaccination against tick-borne encephalitis elicits a detectable NS1 IgG antibody response. J Virol Methods 2023; 322:114831. [PMID: 37838083 DOI: 10.1016/j.jviromet.2023.114831] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 10/10/2023] [Accepted: 10/11/2023] [Indexed: 10/16/2023]
Abstract
Vaccine-induced protection against tick-borne encephalitis virus (TBEV) is mediated by antibodies to the viral particle/envelope protein. The detection of non-structural protein 1 (NS1) specific antibodies has been suggested as a marker indicative of natural infections. However, recent work has shown that TBEV vaccines contain traces of NS1, and immunization of mice induced low amounts of NS1-specific antibodies. In this study, we investigated if vaccination induces TBEV NS1-specific antibodies in humans. Healthy army members (n = 898) were asked to fill in a questionnaire relating to flavivirus vaccination or infection, and blood samples were collected. In addition, samples of 71 suspected acute TBE cases were included. All samples were screened for the presence of TBEV NS1-specific IgG antibodies using an in-house developed ELISA. Antibodies were quantified as percent positivity in reference to a positive control. For qualitative evaluation, cut-off for positivity was defined based on the mean OD of the lower 95% of the vaccinated individuals + 3 SD. We found significantly higher NS1-specific IgG antibody titers (i.e., quantitative evaluation) in individuals having received 2, 3, or 4 or more vaccine doses than in non-vaccinated individuals. Similarly, the percentage of individuals with a positive test result (i.e., qualitative evaluation) was higher in individuals vaccinated against tick-borne encephalitis than in unvaccinated study participants. Although NS1-specific IgG titers remained at a relatively low level when compared to TBE patients, a clear distinction was not always possible. Establishing a clear cut-off point in detection systems is critical for NS1-specific antibodies to serve as a marker for distinguishing the immune response after vaccination and infection.
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Affiliation(s)
- Rahel Ackermann-Gäumann
- Microbiologie, ADMED Analyses et Diagnostics Médicaux, La Chaux-de-Fonds, Switzerland; Swiss National Reference Center for Tick-Transmitted Diseases, Switzerland.
| | - Arthur Brêchet
- Microbiologie, ADMED Analyses et Diagnostics Médicaux, La Chaux-de-Fonds, Switzerland
| | - Jan Smetana
- Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czech Republic
| | - Jiři Salát
- Laboratory of Emerging Viral Infections, Veterinary Research Institute, Brno, Czech Republic; Laboratory of Arbovirology, Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Ceske Budejovice, Czech Republic; Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Reto Lienhard
- Microbiologie, ADMED Analyses et Diagnostics Médicaux, La Chaux-de-Fonds, Switzerland; Swiss National Reference Center for Tick-Transmitted Diseases, Switzerland
| | - Antony Croxatto
- Microbiologie, ADMED Analyses et Diagnostics Médicaux, La Chaux-de-Fonds, Switzerland; Swiss National Reference Center for Tick-Transmitted Diseases, Switzerland
| | - Petra Polcarová
- Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czech Republic
| | - Roman Chlíbek
- Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czech Republic
| | - Daniel Růžek
- Laboratory of Emerging Viral Infections, Veterinary Research Institute, Brno, Czech Republic; Laboratory of Arbovirology, Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Ceske Budejovice, Czech Republic; Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
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Beicht J, Kubinski M, Zdora I, Puff C, Biermann J, Gerlach T, Baumgärtner W, Sutter G, Osterhaus ADME, Prajeeth CK, Rimmelzwaan GF. Induction of humoral and cell-mediated immunity to the NS1 protein of TBEV with recombinant Influenza virus and MVA affords partial protection against lethal TBEV infection in mice. Front Immunol 2023; 14:1177324. [PMID: 37483628 PMCID: PMC10360051 DOI: 10.3389/fimmu.2023.1177324] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 06/20/2023] [Indexed: 07/25/2023] Open
Abstract
Introduction Tick-borne encephalitis virus (TBEV) is one of the most relevant tick-transmitted neurotropic arboviruses in Europe and Asia and the causative agent of tick-borne encephalitis (TBE). Annually more than 10,000 TBE cases are reported despite having vaccines available. In Europe, the vaccines FSME-IMMUN® and Encepur® based on formaldehyde-inactivated whole viruses are licensed. However, demanding vaccination schedules contribute to sub-optimal vaccination uptake and breakthrough infections have been reported repeatedly. Due to its immunogenic properties as well as its role in viral replication and disease pathogenesis, the non-structural protein 1 (NS1) of flaviviruses has become of interest for non-virion based flavivirus vaccine candidates in recent years. Methods Therefore, immunogenicity and protective efficacy of TBEV NS1 expressed by neuraminidase (NA)-deficient Influenza A virus (IAV) or Modified Vaccinia virus Ankara (MVA) vectors were investigated in this study. Results With these recombinant viral vectors TBEV NS1-specific antibody and T cell responses were induced. Upon heterologous prime/boost regimens partial protection against lethal TBEV challenge infection was afforded in mice. Discussion This supports the inclusion of NS1 as a vaccine component in next generation TBEV vaccines.
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Affiliation(s)
- Jana Beicht
- Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Mareike Kubinski
- Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Isabel Zdora
- Department of Pathology, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
- Center for Systems Neuroscience, Hannover Graduate School for Neurosciences, Infection Medicine, and Veterinary Sciences (HGNI), Hannover, Germany
| | - Christina Puff
- Department of Pathology, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Jeannine Biermann
- Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Thomas Gerlach
- Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Wolfgang Baumgärtner
- Department of Pathology, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
- Center for Systems Neuroscience, Hannover Graduate School for Neurosciences, Infection Medicine, and Veterinary Sciences (HGNI), Hannover, Germany
| | - Gerd Sutter
- Division of Virology, Institute for Infectious Diseases and Zoonoses, Ludwig Maximilian University (LMU) Munich, Munich, Germany
- German Center for Infection Research (DZIF), Partner Site Munich, Munich, Germany
| | - Albert D. M. E. Osterhaus
- Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Chittappen Kandiyil Prajeeth
- Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Guus F. Rimmelzwaan
- Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
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Zhang J, He Q, Yan X, Liu J, Bai Y, An C, Cui B, Gao F, Mao Q, Wang J, Xu M, Liang Z. Mixed formulation of mRNA and protein‐based COVID‐19 vaccines triggered superior neutralizing antibody responses. MedComm (Beijing) 2022; 3:e188. [DOI: 10.1002/mco2.188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 11/02/2022] [Accepted: 11/03/2022] [Indexed: 12/03/2022] Open
Affiliation(s)
- Jialu Zhang
- Division of Hepatitis and Enterovirus Vaccines, Institute of Biological Products, National Institutes for Food and Drug Control NHC Key Laboratory of Research on Quality and Standardization of Biotech Products, NMPA Key Laboratory for Quality Research and Evaluation of Biological Products Beijing People's Republic of China
| | - Qian He
- Division of Hepatitis and Enterovirus Vaccines, Institute of Biological Products, National Institutes for Food and Drug Control NHC Key Laboratory of Research on Quality and Standardization of Biotech Products, NMPA Key Laboratory for Quality Research and Evaluation of Biological Products Beijing People's Republic of China
| | - Xujia Yan
- Division of Hepatitis and Enterovirus Vaccines, Institute of Biological Products, National Institutes for Food and Drug Control NHC Key Laboratory of Research on Quality and Standardization of Biotech Products, NMPA Key Laboratory for Quality Research and Evaluation of Biological Products Beijing People's Republic of China
| | - Jianyang Liu
- Division of Hepatitis and Enterovirus Vaccines, Institute of Biological Products, National Institutes for Food and Drug Control NHC Key Laboratory of Research on Quality and Standardization of Biotech Products, NMPA Key Laboratory for Quality Research and Evaluation of Biological Products Beijing People's Republic of China
| | - Yu Bai
- Division of Hepatitis and Enterovirus Vaccines, Institute of Biological Products, National Institutes for Food and Drug Control NHC Key Laboratory of Research on Quality and Standardization of Biotech Products, NMPA Key Laboratory for Quality Research and Evaluation of Biological Products Beijing People's Republic of China
| | - Chaoqiang An
- Division of Hepatitis and Enterovirus Vaccines, Institute of Biological Products, National Institutes for Food and Drug Control NHC Key Laboratory of Research on Quality and Standardization of Biotech Products, NMPA Key Laboratory for Quality Research and Evaluation of Biological Products Beijing People's Republic of China
| | - Bopei Cui
- Division of Hepatitis and Enterovirus Vaccines, Institute of Biological Products, National Institutes for Food and Drug Control NHC Key Laboratory of Research on Quality and Standardization of Biotech Products, NMPA Key Laboratory for Quality Research and Evaluation of Biological Products Beijing People's Republic of China
| | - Fan Gao
- Division of Hepatitis and Enterovirus Vaccines, Institute of Biological Products, National Institutes for Food and Drug Control NHC Key Laboratory of Research on Quality and Standardization of Biotech Products, NMPA Key Laboratory for Quality Research and Evaluation of Biological Products Beijing People's Republic of China
| | - Qunying Mao
- Division of Hepatitis and Enterovirus Vaccines, Institute of Biological Products, National Institutes for Food and Drug Control NHC Key Laboratory of Research on Quality and Standardization of Biotech Products, NMPA Key Laboratory for Quality Research and Evaluation of Biological Products Beijing People's Republic of China
| | - Junzhi Wang
- Division of Hepatitis and Enterovirus Vaccines, Institute of Biological Products, National Institutes for Food and Drug Control NHC Key Laboratory of Research on Quality and Standardization of Biotech Products, NMPA Key Laboratory for Quality Research and Evaluation of Biological Products Beijing People's Republic of China
| | - Miao Xu
- Division of Hepatitis and Enterovirus Vaccines, Institute of Biological Products, National Institutes for Food and Drug Control NHC Key Laboratory of Research on Quality and Standardization of Biotech Products, NMPA Key Laboratory for Quality Research and Evaluation of Biological Products Beijing People's Republic of China
| | - Zhenglun Liang
- Division of Hepatitis and Enterovirus Vaccines, Institute of Biological Products, National Institutes for Food and Drug Control NHC Key Laboratory of Research on Quality and Standardization of Biotech Products, NMPA Key Laboratory for Quality Research and Evaluation of Biological Products Beijing People's Republic of China
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Salat J, Strakova P, Ruzek D. Dynamics of Whole Virus and Non-Structural Protein 1 (NS1) IgG Response in Mice Immunized with Two Commercial Tick-Borne Encephalitis Vaccines. Vaccines (Basel) 2022; 10:vaccines10071001. [PMID: 35891164 PMCID: PMC9320558 DOI: 10.3390/vaccines10071001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 06/18/2022] [Accepted: 06/19/2022] [Indexed: 01/27/2023] Open
Abstract
The presence of a non-structural protein 1 (NS1) in tick-borne encephalitis (TBE) vaccines and the possible induction of an NS1-specific immune response in vaccinated individuals remains a somewhat controversial topic. Previously, we detected the presence of NS1 in the Encepur TBE vaccine by mass spectrometry and found the induction of NS1-specific IgG antibodies in mice vaccinated with the FSME-Immun TBE vaccine. Here, in this follow-up study, we examined the dynamics and extent of the NS1-specific IgG response in mice vaccinated with these two vaccines in more detail and compared it with the IgG response to the whole virus (WV). Mice were vaccinated at two-week intervals with a total of six doses of each vaccine, and levels of IgG antibodies to TBE virus WV and NS1 were measured by ELISA after each dose. Both vaccines elicited a robust anti-WV IgG response after two doses. The Encepur vaccine did not elicit NS1-specific IgG even after all six doses. In contrast, the FSME-Immun vaccine triggered the production of NS1-specific IgG after four doses. The results indicate that FSME-Immun is the only vaccine that elicits an NS1-specific antibody response in mice. However, compared to WV-specific IgG, the NS1-specific response is weaker, and a higher number of doses is required to induce detectable levels of NS1-specific IgG antibodies.
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Affiliation(s)
- Jiri Salat
- Laboratory of Emerging Viral Infections, Veterinary Research Institute, Hudcova 70, CZ-62100 Brno, Czech Republic;
- Laboratory of Arbovirology, Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branisovska 31, CZ-37005 Ceske Budejovice, Czech Republic
- Correspondence: (J.S.); (D.R.)
| | - Petra Strakova
- Laboratory of Emerging Viral Infections, Veterinary Research Institute, Hudcova 70, CZ-62100 Brno, Czech Republic;
- Laboratory of Arbovirology, Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branisovska 31, CZ-37005 Ceske Budejovice, Czech Republic
| | - Daniel Ruzek
- Laboratory of Emerging Viral Infections, Veterinary Research Institute, Hudcova 70, CZ-62100 Brno, Czech Republic;
- Laboratory of Arbovirology, Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branisovska 31, CZ-37005 Ceske Budejovice, Czech Republic
- Department of Experimental Biology, Faculty of Science, Masaryk University, Kamenice 735/5, CZ-62500 Brno, Czech Republic
- Correspondence: (J.S.); (D.R.)
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Kubinski M, Beicht J, Gerlach T, Volz A, Sutter G, Rimmelzwaan GF. Tick-Borne Encephalitis Virus: A Quest for Better Vaccines against a Virus on the Rise. Vaccines (Basel) 2020; 8:E451. [PMID: 32806696 PMCID: PMC7564546 DOI: 10.3390/vaccines8030451] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 08/06/2020] [Accepted: 08/10/2020] [Indexed: 12/15/2022] Open
Abstract
Tick-borne encephalitis virus (TBEV), a member of the family Flaviviridae, is one of the most important tick-transmitted viruses in Europe and Asia. Being a neurotropic virus, TBEV causes infection of the central nervous system, leading to various (permanent) neurological disorders summarized as tick-borne encephalitis (TBE). The incidence of TBE cases has increased due to the expansion of TBEV and its vectors. Since antiviral treatment is lacking, vaccination against TBEV is the most important protective measure. However, vaccination coverage is relatively low and immunogenicity of the currently available vaccines is limited, which may account for the vaccine failures that are observed. Understanding the TBEV-specific correlates of protection is of pivotal importance for developing novel and improved TBEV vaccines. For affording robust protection against infection and development of TBE, vaccines should induce both humoral and cellular immunity. In this review, the adaptive immunity induced upon TBEV infection and vaccination as well as novel approaches to produce improved TBEV vaccines are discussed.
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Affiliation(s)
- Mareike Kubinski
- Research Center for Emerging Infections and Zoonoses (RIZ), University of Veterinary Medicine Hannover, Foundation (TiHo), Buenteweg 17, 30559 Hannover, Germany; (M.K.); (J.B.); (T.G.)
| | - Jana Beicht
- Research Center for Emerging Infections and Zoonoses (RIZ), University of Veterinary Medicine Hannover, Foundation (TiHo), Buenteweg 17, 30559 Hannover, Germany; (M.K.); (J.B.); (T.G.)
| | - Thomas Gerlach
- Research Center for Emerging Infections and Zoonoses (RIZ), University of Veterinary Medicine Hannover, Foundation (TiHo), Buenteweg 17, 30559 Hannover, Germany; (M.K.); (J.B.); (T.G.)
| | - Asisa Volz
- Institute of Virology, University of Veterinary Medicine Hannover, Foundation (TiHo), Buenteweg 17, 30559 Hannover, Germany;
| | - Gerd Sutter
- Institute for Infectious Diseases and Zoonoses, Ludwig-Maximilians-University (LMU) Munich, Veterinaerstr. 13, 80539 Munich, Germany;
| | - Guus F. Rimmelzwaan
- Research Center for Emerging Infections and Zoonoses (RIZ), University of Veterinary Medicine Hannover, Foundation (TiHo), Buenteweg 17, 30559 Hannover, Germany; (M.K.); (J.B.); (T.G.)
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Salat J, Mikulasek K, Larralde O, Pokorna Formanova P, Chrdle A, Haviernik J, Elsterova J, Teislerova D, Palus M, Eyer L, Zdrahal Z, Petrik J, Ruzek D. Tick-Borne Encephalitis Virus Vaccines Contain Non-Structural Protein 1 Antigen and may Elicit NS1-Specific Antibody Responses in Vaccinated Individuals. Vaccines (Basel) 2020; 8:vaccines8010081. [PMID: 32059489 PMCID: PMC7157539 DOI: 10.3390/vaccines8010081] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 02/04/2020] [Accepted: 02/10/2020] [Indexed: 01/09/2023] Open
Abstract
Vaccination against tick-borne encephalitis (TBE) is based on the use of formalin-inactivated, culture-derived whole-virus vaccines. Immune response following vaccination is primarily directed to the viral envelope (E) protein, the major viral surface antigen. In Europe, two TBE vaccines are available in adult and pediatric formulations, namely FSME-IMMUN® (Pfizer) and Encepur® (GlaxoSmithKline). Herein, we analyzed the content of these vaccines using mass spectrometry (MS). The MS analysis revealed that the Encepur vaccine contains not only proteins of the whole virus particle, but also viral non-structural protein 1 (NS1). MS analysis of the FSME-IMMUN vaccine failed due to the high content of human serum albumin used as a stabilizer in the vaccine. However, the presence of NS1 in FSME-IMMUN was confirmed by immunization of mice with six doses of this vaccine, which led to a robust anti-NS1 antibody response. NS1-specific Western blot analysis also detected anti-NS1 antibodies in sera of humans who received multiple doses of either of these two vaccines; however, most vaccinees who received ≤3 doses were negative for NS1-specific antibodies. The contribution of NS1-specific antibodies to protection against TBE was demonstrated by immunization of mice with purified NS1 antigen, which led to a significant (p < 0.01) prolongation of the mean survival time after lethal virus challenge. This indicates that stimulation of anti-NS1 immunity by the TBE vaccines may increase their protective effect.
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Affiliation(s)
- Jiri Salat
- Veterinary Research Institute, Hudcova 70, CZ-62100 Brno, Czech Republic; (J.S.); (P.P.F.); (J.H.); (J.E.); (M.P.); (L.E.)
| | - Kamil Mikulasek
- Central European Institute of Technology, Masaryk University, Kamenice 753/5, CZ-62500 Brno, Czech Republic; (K.M.); (Z.Z.)
| | - Osmany Larralde
- The Jack Copland Centre, Scottish National Blood Transfusion Service, 52 Research Avenue North, Edinburgh EH14 4BE, UK; (O.L.); (J.P.)
| | - Petra Pokorna Formanova
- Veterinary Research Institute, Hudcova 70, CZ-62100 Brno, Czech Republic; (J.S.); (P.P.F.); (J.H.); (J.E.); (M.P.); (L.E.)
| | - Ales Chrdle
- Hospital Ceske Budejovice, B. Nemcove 585/54, 370 01 Ceske Budejovice, Czech Republic; (A.C.); (D.T.)
- Royal Liverpool University Hospital, Prescot St, Liverpool L7 8XP, UK
| | - Jan Haviernik
- Veterinary Research Institute, Hudcova 70, CZ-62100 Brno, Czech Republic; (J.S.); (P.P.F.); (J.H.); (J.E.); (M.P.); (L.E.)
- Faculty of Science, Masaryk University, Kamenice 753/5, CZ-62500 Brno, Czech Republic
| | - Jana Elsterova
- Veterinary Research Institute, Hudcova 70, CZ-62100 Brno, Czech Republic; (J.S.); (P.P.F.); (J.H.); (J.E.); (M.P.); (L.E.)
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branisovska 31, CZ-37006 Ceske Budejovice, Czech Republic
- Faculty of Science, University of South Bohemia, Branisovska 31, CZ-37006 Ceske Budejovice, Czech Republic
| | - Dana Teislerova
- Hospital Ceske Budejovice, B. Nemcove 585/54, 370 01 Ceske Budejovice, Czech Republic; (A.C.); (D.T.)
| | - Martin Palus
- Veterinary Research Institute, Hudcova 70, CZ-62100 Brno, Czech Republic; (J.S.); (P.P.F.); (J.H.); (J.E.); (M.P.); (L.E.)
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branisovska 31, CZ-37006 Ceske Budejovice, Czech Republic
| | - Ludek Eyer
- Veterinary Research Institute, Hudcova 70, CZ-62100 Brno, Czech Republic; (J.S.); (P.P.F.); (J.H.); (J.E.); (M.P.); (L.E.)
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branisovska 31, CZ-37006 Ceske Budejovice, Czech Republic
| | - Zbynek Zdrahal
- Central European Institute of Technology, Masaryk University, Kamenice 753/5, CZ-62500 Brno, Czech Republic; (K.M.); (Z.Z.)
| | - Juraj Petrik
- The Jack Copland Centre, Scottish National Blood Transfusion Service, 52 Research Avenue North, Edinburgh EH14 4BE, UK; (O.L.); (J.P.)
| | - Daniel Ruzek
- Veterinary Research Institute, Hudcova 70, CZ-62100 Brno, Czech Republic; (J.S.); (P.P.F.); (J.H.); (J.E.); (M.P.); (L.E.)
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branisovska 31, CZ-37006 Ceske Budejovice, Czech Republic
- Correspondence: ; Tel.: +420-777-786-218
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Galula JU, Yang CY, Davis BS, Chang GJJ, Chao DY. Cross-reactivity reduced dengue virus 2 vaccine has no cross-protection against heterotypic dengue viruses. Future Virol 2020. [DOI: 10.2217/fvl-2019-0115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Aim: This study assessed how prime-boost strategies influence the immunogenicity of a cross-reactivity reduced dengue virus 2 vaccine (DENV-2 RD). Materials & methods: Mice were immunized with DENV-2 RD vaccines in a heterologous DNA and virus-like particle (VLP) prime-boost. Elicited antibodies were analyzed for neutralization and protective efficacy against four DENV serotypes. Results: DENV-2 RD DNA-VLP had induced higher and broader levels of total IgG and neutralizing antibodies with statistically significant IgG titers against DENV-2 and -3. Only pups of DENV-2 RD DNA-VLP immunized female mice were fully protected against homotypic DENV challenge and partially protected (60% survival rate) against heterotypic DENV-3 lethal challenge. Conclusion: DENV-2 RD vaccine requires a multivalent format to effectively elicit a balanced and protective immunity across all four DENV serotypes.
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Affiliation(s)
- Jedhan U Galula
- Graduate Institute of Microbiology & Public Health, College of Veterinary Medicine, National Chung Hsing University, Taichung 402, Taiwan
| | - Chung-Yu Yang
- Graduate Institute of Microbiology & Public Health, College of Veterinary Medicine, National Chung Hsing University, Taichung 402, Taiwan
| | - Brent S Davis
- Division of Vector-Borne Diseases, Centers for Disease Control & Prevention, US Department of Health & Human Services, Fort Collins, CO 80521, USA
| | - Gwong-Jen J Chang
- Division of Vector-Borne Diseases, Centers for Disease Control & Prevention, US Department of Health & Human Services, Fort Collins, CO 80521, USA
| | - Day-Yu Chao
- Graduate Institute of Microbiology & Public Health, College of Veterinary Medicine, National Chung Hsing University, Taichung 402, Taiwan
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Valdés I, Lazo L, Hermida L, Guillén G, Gil L. Can Complementary Prime-Boost Immunization Strategies Be an Alternative and Promising Vaccine Approach Against Dengue Virus? Front Immunol 2019; 10:1956. [PMID: 31507591 PMCID: PMC6718459 DOI: 10.3389/fimmu.2019.01956] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 08/02/2019] [Indexed: 12/27/2022] Open
Abstract
Dengue is one of the most important diseases transmitted by mosquitoes. Dengvaxia®, a vaccine registered in several countries, cannot be administered to non-immune individuals and children younger than 9 years old, due to safety reasons. There are two vaccine candidates in phase 3 efficacy trials, but their registration date is completely unknown at this moment. So, the development of new vaccines or vaccine strategies continues to be a priority for the WHO. This work reviews some complementary prime-boost immunization studies against important human pathogens. Additionally, it reviews the results obtained using this regimen of immunization against dengue virus as a potential alternative approach for finding a safe and efficient vaccine. Finally, the main elements associated with this strategy are also discussed. The generation of new strategies of vaccination against dengue virus, must be directed to reduce the risk of increasing viral load through sub-neutralizing antibodies and it must be also directed to induce a polyfunctional T cell response. Complementary prime-boost immunization strategies could emerge as an interesting approach to induce solid immunity or at least to reduce viral load after natural infection, avoiding severe dengue. Subunit vaccine could be safe and attractive antigens for this strategy, especially proteins including B, and T-cells epitopes for inducing humoral and cellular immune responses, which can play an important role controlling the disease.
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Affiliation(s)
- Iris Valdés
- Vaccine Department, Center for Genetic Engineering and Biotechnology, Havana, Cuba
| | - Laura Lazo
- Vaccine Department, Center for Genetic Engineering and Biotechnology, Havana, Cuba
| | - Lisset Hermida
- Vaccine Department, Center for Genetic Engineering and Biotechnology, Havana, Cuba
| | - Gerardo Guillén
- Vaccine Department, Center for Genetic Engineering and Biotechnology, Havana, Cuba
| | - Lázaro Gil
- Vaccine Department, Center for Genetic Engineering and Biotechnology, Havana, Cuba
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Lashkevich VA, Karganova GG. ON MODERN APPROACHES TO CREATION OF A SINGLE-CYCLE VACCINE AGAINST TICK-BORNE ENCEPHALITIS. Vopr Virusol 2018; 63:101-105. [PMID: 36494935 DOI: 10.18821/0507-4088-2018-63-3-101-105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Indexed: 06/17/2023]
Abstract
In Russia, about 2000 people get tick-borne encephalitis (TBE) every year. Almost none of them are vaccinated. For the prevention of TBE, inactivated vaccines (IVTBE) are used. IVTBE are safe and protect from TBE not less than 95% of vaccinated. The disadvantages of IVTBE are the need for numerous intramuscular injections by medical personnel, the high cost of vaccination and the vaccination refusals. A new vaccine against TBE should not be inferior to IVTBE in its safety and efficacy, should cause long-term immunity after a single application, and, preferably, be effective after oral administration. Currently, genetic engineering methods for producing replication-defective (single-cycle) flaviviruses that can serve as the basis for creating new types of safe vaccines similar in many characteristics to classic live vaccines based on attenuated strains of viruses have been proposed. The possibility of infecting humans with TBE by the use of milk of naturally infected animals, as well as the experience of using experimental live TBE vaccines, are prerequisites for the creation of a safe oral single-dose TBE vaccine.
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Affiliation(s)
- V A Lashkevich
- Chumakov Federal Scientific Center for Research and Development of Immune and Biological Products of Russian Academy of Sciences
| | - G G Karganova
- Chumakov Federal Scientific Center for Research and Development of Immune and Biological Products of Russian Academy of Sciences
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11
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Kuzmenko YV, Starodubova ES, Shevtsova AS, Chernokhaeva LL, Latanova AA, Preobrazhenskaia OV, Timofeev AV, Karganova GG, Karpov VL. Intracellular degradation and localization of NS1 of tick-borne encephalitis virus affect its protective properties. J Gen Virol 2017; 98:50-55. [PMID: 28221100 DOI: 10.1099/jgv.0.000700] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Currently, many DNA vaccines against infectious diseases are in clinical trials; however, their efficacy needs to be improved. The potency of DNA immunogen can be optimized by targeting technologies. In the current study, to increase the efficacy of NS1 encoded by plasmid, proteasome targeting was applied. NS1 variants with or without translocation sequence and with ornithine decarboxylase as a signal of proteasomal degradation were tested for expression, localization, protein turnover, proteasomal degradation and protection properties. Deletion of translocation signal abrogated presentation of NS1 on the cell surface and increased proteasomal processing of NS1. Fusion with ornithine decarboxylase led to an increase of protein turnover and the proteasome degradation rate of NS1. Immunization with NS1 variants with increased proteasome processing protected mice from viral challenge only partially; however, the survival time of infected mice was prolonged in these groups. These data can give a presupposition for formulation of specific immune therapy for infected individuals.
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Affiliation(s)
- Yulia V Kuzmenko
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
| | | | - Anastasia S Shevtsova
- Chumakov Institute of Poliomyelitis and Viral Encephalitides (Chumakov IPVE), Chumakov FSC R&D IBP RAS, Moscow, Russia
| | - Liubov L Chernokhaeva
- Chumakov Institute of Poliomyelitis and Viral Encephalitides (Chumakov IPVE), Chumakov FSC R&D IBP RAS, Moscow, Russia
| | - Anastasia A Latanova
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
| | | | - Andrey V Timofeev
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
| | - Galina G Karganova
- Chumakov Institute of Poliomyelitis and Viral Encephalitides (Chumakov IPVE), Chumakov FSC R&D IBP RAS, Moscow, Russia
| | - Vadim L Karpov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia
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Kuzmenko YV, Starodubova ES, Karganova GG, Timofeev AV, Karpov VL. Nonstructural protein 1 of tick-borne encephalitis virus activates the expression of immunoproteasome subunits. Mol Biol 2016. [DOI: 10.1134/s0026893316020126] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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13
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Bolhassani A, Kardani K, Vahabpour R, Habibzadeh N, Aghasadeghi MR, Sadat SM, Agi E. Prime/boost immunization with HIV-1 MPER-V3 fusion construct enhances humoral and cellular immune responses. Immunol Lett 2015; 168:366-73. [PMID: 26518142 DOI: 10.1016/j.imlet.2015.10.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Revised: 10/17/2015] [Accepted: 10/20/2015] [Indexed: 01/15/2023]
Abstract
Development of an effective vaccine against HIV-1 infection is a main concern in worldwide. A potent vaccine for HIV-1 requires the induction and maintenance of both humoral and cellular immunity. In this study, the levels of humoral and cellular immune responses were compared using MPER-V3 injection in three immunization strategies such as DNA/DNA, peptide/peptide, and DNA/peptide (prime-boost). MPG peptide and Montanide 720 were used as a DNA delivery system, and as a peptide adjuvant, respectively. Our results demonstrated that MPG forms stable non-covalent nanoparticles with plasmid DNA at N/P ratio of 10:1 (∼ 110-130 nm). The in vitro transfection efficiency of MPER-V3 DNA using MPG was comparable with lipofectamine and turbofect reagents as a common delivery system. In vivo prime-boost immunization using HIV-1 MPER-V3 could significantly enhance humoral and cellular immune responses as compared to control groups. The mixture of IgG1 and IgG2a was observed for each strategy, but IFN-γ production was significantly higher in prime-boost and peptide immunizations than that in DNA immunizations, inducing Th1 response. Moreover, our data showed that prime immunization with low dose of the nanoparticles (MPER-V3 DNA: MPG at ratio of 1:10) followed by MPER-V3 peptide drives T cell responses towards a Th1-type similar to high dose of the naked DNA prime/peptide boost immunization. Generally, the prime-boost strategy could improve both immune responses against MPER and especially V3 peptides suggesting its application as a promising HIV vaccine candidate in future.
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Affiliation(s)
- Azam Bolhassani
- Department of Hepatitis and AIDS, Pasteur Institute of Iran, Tehran, Iran.
| | - Kimia Kardani
- Department of Biotechnology, Faculty of Advanced Sciences and Technology, Pharmaceutical Sciences Branch, Islamic Azad University, Tehran, Iran
| | | | - Nourieh Habibzadeh
- Department of Hepatitis and AIDS, Pasteur Institute of Iran, Tehran, Iran
| | | | - Seyed Mehdi Sadat
- Department of Hepatitis and AIDS, Pasteur Institute of Iran, Tehran, Iran
| | - Elnaz Agi
- Department of Hepatitis and AIDS, Pasteur Institute of Iran, Tehran, Iran
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Venanzi F, Shifrin V, Sherman M, Gabai V, Kiselev O, Komissarov A, Grudinin M, Shartukova M, Romanovskaya-Romanko EA, Kudryavets Y, Bezdenezhnykh N, Lykhova O, Semesyuk N, Concetti A, Tsyb A, Filimonova M, Makarchuk V, Yakubovsky R, Chursov A, Shcherbinina V, Shneider A. Broad-spectrum anti-tumor and anti-metastatic DNA vaccine based on p62-encoding vector. Oncotarget 2014; 4:1829-35. [PMID: 24121124 PMCID: PMC3858567 DOI: 10.18632/oncotarget.1397] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Autophagy plays an important role in neoplastic transformation of cells and in resistance of cancer cells to radio- and chemotherapy. p62 (SQSTM1) is a key component of autophagic machinery which is also involved in signal transduction. Although recent empirical observations demonstrated that p62 is overexpressed in variety of human tumors, a mechanism of p62 overexpression is not known. Here we report that the transformation of normal human mammary epithelial cells with diverse oncogenes (RAS, PIK3CA and Her2) causes marked accumulation of p62. Based on this result, we hypothesized that p62 may be a feasible candidate to be an anti-cancer DNA vaccine. Here we performed a preclinical study of a novel DNA vaccine encoding p62. Intramuscularly administered p62-encoding plasmid induced anti-p62 antibodies and exhibited strong antitumor activity in four models of allogeneic mouse tumors - B16 melanoma, Lewis lung carcinoma (LLC), S37 sarcoma, and Ca755 breast carcinoma. In mice challenged with Ca755 cells, p62 treatment had dual effect: inhibited tumor growth in some mice and prolonged life in those mice which developed tumor size similar to control. P62-encoding plasmid has demonstrated its potency both as a preventive and therapeutic vaccine. Importantly, p62 vaccination drastically suppressed metastasis formation: in B16 melanoma where tumor cells where injected intravenously, and in LLC and S37 sarcoma with spontaneous metastasis. Overall, we conclude that a p62-encoding vector(s) constitute(s) a novel, effective broad-spectrum antitumor and anti-metastatic vaccine feasible for further development and clinical trials.
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Affiliation(s)
- Franco Venanzi
- Laboratory of Translational Biology, Department of Biology MCA, University of Camerino, Italy
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Hua RH, Liu LK, Chen ZS, Li YN, Bu ZG. Comprehensive Mapping Antigenic Epitopes of NS1 Protein of Japanese Encephalitis Virus with Monoclonal Antibodies. PLoS One 2013; 8:e67553. [PMID: 23825668 PMCID: PMC3688998 DOI: 10.1371/journal.pone.0067553] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Accepted: 05/20/2013] [Indexed: 11/19/2022] Open
Abstract
Japanese encephalitis virus (JEV) non-structural protein 1 (NS1) contributes to virus replication and elicits protective immune responses during infection. JEV NS1-specific antibody responses could be a target in the differential diagnosis of different flavivirus infections. However, the epitopes on JEV NS1 are poorly characterized. The present study describes the full mapping of linear B-cell epitopes in JEV NS1. We generated eleven NS1-specific monoclonal antibodies from mice immunized with recombinant NS1. For epitope mapping of monoclonal antibodies, a set of 51 partially-overlapping peptides covering the entire NS1 protein were expressed with a GST-tag and then screened using monoclonal antibodies. Through enzyme-linked immunosorbent assay (ELISA), five linear epitope-containing peptides were identified. By sequentially removing amino acid residues from the carboxy and amino terminal of peptides, the minimal units of the five linear epitopes were identified and confirmed using monoclonal antibodies. Five linear epitopes are located in amino acids residues (5)AIDITRK(11), (72)RDELNVL(78), (251)KSKHNRREGY(260), (269)DENGIVLD(276), and (341)DETTLVRS(348). Furthermore, it was found that the epitopes are highly conserved among JEV strains through sequence alignment. Notably, none of the homologous regions on NS1 proteins from other flaviviruses reacted with the MAbs when they were tested for cross-reactivity, and all five epitope peptides were not recognized by sera against West Nile virus or Dengue virus. These novel virus-specific linear B-cell epitopes of JEV NS1 would benefit the development of new vaccines and diagnostic assays.
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Affiliation(s)
- Rong-Hong Hua
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, Heilongjiang, People's Republic of China
- * E-mail:
| | - Li-Ke Liu
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, Heilongjiang, People's Republic of China
| | - Zhen-Shi Chen
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, Heilongjiang, People's Republic of China
| | - Ye-Nan Li
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, Heilongjiang, People's Republic of China
| | - Zhi-Gao Bu
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, Heilongjiang, People's Republic of China
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A molecular evaluation of dengue virus pathogenesis and its latest vaccine strategies. Mol Biol Rep 2010; 38:3731-40. [PMID: 21107723 DOI: 10.1007/s11033-010-0488-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2010] [Accepted: 11/09/2010] [Indexed: 10/18/2022]
Abstract
More than one third of the world's population living in tropical and subtropical areas of the world is at risk of dengue infections and as many as 100 million people are yearly infected. This disease has reemerged during the past 20 years in the form of an epidemic. Dengue is caused by one of four related serotypes of dengue virus and often leads to severe forms of the disease, resulting commonly from secondary infections. Dengue virus is a mosquito borne virus, belongs to the family Flaviviridae and consists of a single stranded positive sense RNA genome. Like other RNA viruses it escapes defense mechanisms and neutralization attempts by mutations, which make it more resistant and adaptable to its environment. Antiviral strategies and vaccine development is thus impaired and hence to date there is no licensed vaccine available for dengue virus. Here we discuss various efforts made towards the identification of potential vaccine targets for dengue as well as various strategies employed by research groups/pharmaceutical companies towards the development of a successful dengue vaccine.
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The effect of controlled therapy interruption in chronic HCV infection: enhanced host immune response? A hypothesis. J Clin Virol 2009; 44:149-51. [PMID: 19157972 DOI: 10.1016/j.jcv.2008.11.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2008] [Revised: 11/25/2008] [Accepted: 11/26/2008] [Indexed: 11/20/2022]
Abstract
BACKGROUND We have hypothesized that prolonged viral suppression partially reverses immune tolerance in chronic hepatitis C virus infection. Brief periods of treatment interruption can then simulate 'auto-vaccination' and evoke powerful secondary host immune responses. OBJECTIVE To determine the effect of controlled therapy interruption CTI on viral load in previous relapsers to interferon and ribavirin treatment. STUDY DESIGN Virus is maintained at undetectable levels for 2-8 weeks with pegylated interferon and ribavirin and then briefly interrupted, restarting as soon as viremia returns (cycle 1). It is suppressed for at least a further 4 weeks, then briefly interrupted again (cycle 2). RESULTS Viremia relapsed within 2-4 weeks (time to relapse TTR) after the first treatment interruption in all four patients in cycle 1. TTR increased sevenfold with the second treatment interruption in patient 1 and was followed by sustained virological response with cycle 3. In patient 2, TTR increased threefold after cycle 2 and subsequent cycles. Serum ALT and bilirubin rose significantly with treatment interruption during cycles 2 and 3, returning to baseline with treatment resumption. Serum bilirubin rose to 12.3mg/dl when two doses of pegylated interferon were missed during cycle 4. In patients 3 and 4, TTR was unchanged after three consecutive cycles. However, VL has remained more than 1 log below baseline for up to 18 months in both. CONCLUSIONS These observations suggest that CTI exerts significant control of chronic hepatitis C viremia.
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Rosas CT, Goodman LB, von Einem J, Osterrieder N. Equine herpesvirus type 1 modified live virus vaccines: quo vaditis? Expert Rev Vaccines 2006; 5:119-31. [PMID: 16451114 DOI: 10.1586/14760584.5.1.119] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Infections of horses with equine herpesvirus type 1 (EHV-1) have garnered new attention over the last few years. Devastating outbreaks occurring worldwide, primarily of the neurologic form of the disease, have resulted in a reassessment of the control strategies, and particularly the prophylactic measures, that are necessary to keep the infection and spread of disease in check. Most of the available EHV-1 vaccines are based on preparations of inactivated virus, which are applied monovalently for prevention of EHV-1-caused abortion in pregnant mares or as part of multivalent vaccines to prevent respiratory disease. Despite the importance of an induction of cytotoxic immune responses for protection against EHV-1-induced disease, only two modified live virus vaccine preparations, which are both based on the avirulent EHV-1 strain RacH and were developed more than 40 years ago, are commercially available. Current efforts focus on exploiting the available infectious bacterial artificial chromosome clones of various EHV-1 strains to engineer a new generation of modified live virus vaccines. Both more efficient and long-lasting anti-EHV-1 immunity and delivery of immunogens of other pathogens are attempted and within immediate reach. The improvement of modified live virus vaccines will likely be a major focus of research in the future, and will hopefully help to more completely protect horses against one of the most important and devastating viral diseases.
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Affiliation(s)
- Cristina T Rosas
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
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