1
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Allen JD, Ross TM. mRNA vaccines encoding computationally optimized hemagglutinin elicit protective antibodies against future antigenically drifted H1N1 and H3N2 influenza viruses isolated between 2018-2020. Front Immunol 2024; 15:1334670. [PMID: 38533508 PMCID: PMC10963417 DOI: 10.3389/fimmu.2024.1334670] [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: 11/07/2023] [Accepted: 02/12/2024] [Indexed: 03/28/2024] Open
Abstract
Background The implementation of mRNA vaccines against COVID-19 has successfully validated the safety and efficacy of the platform, while at the same time revealing the potential for their applications against other infectious diseases. Traditional seasonal influenza vaccines often induce strain specific antibody responses that offer limited protection against antigenically drifted viruses, leading to reduced vaccine efficacy. Modern advances in viral surveillance and sequencing have led to the development of in-silico methodologies for generating computationally optimized broadly reactive antigens (COBRAs) to improve seasonal influenza vaccines. Methods In this study, immunologically naïve mice were intramuscularly vaccinated with mRNA encoding H1 and H3 COBRA hemagglutinins (HA) or wild-type (WT) influenza HAs encapsulated in lipid nanoparticles (LNPs). Results Mice vaccinated with H1 and H3 COBRA HA-encoding mRNA vaccines generated robust neutralizing serum antibody responses against more antigenically distinct contemporary and future drifted H1N1 and H3N2 influenza strains than those vaccinated with WT H1 and H3 HA-encoding mRNA vaccines. The H1 and H3 COBRA HA-encoding mRNA vaccines also prevented influenza illness, including severe disease in the mouse model against H1N1 and H3N2 viruses. Conclusions This study highlights the potential benefits of combining universal influenza antigen design technology with modern vaccine delivery platforms and exhibits how these vaccines can be advantageous over traditional WT vaccine antigens at eliciting superior protective antibody responses against a broader number of influenza virus isolates.
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Affiliation(s)
- James D Allen
- Center for Vaccines and Immunology, University of Georgia, Athens, GA, United States
- Department of Infectious Diseases, University of Georgia, Athens, GA, United States
- Florida Research and Innovation Center, Cleveland Clinic, Port Saint Lucie, FL, United States
| | - Ted M Ross
- Center for Vaccines and Immunology, University of Georgia, Athens, GA, United States
- Department of Infectious Diseases, University of Georgia, Athens, GA, United States
- Florida Research and Innovation Center, Cleveland Clinic, Port Saint Lucie, FL, United States
- Department of Infection Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, United States
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2
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Serial Passaging of Seasonal H3N2 Influenza A/Singapore/G2-31.1/2014 Virus in MDCK-SIAT1 Cells and Primary Chick Embryo Cells Generates HA D457G Mutation and Other Variants in HA, NA, PB1, PB1-F2, and NS1. Int J Mol Sci 2022; 23:ijms232012408. [PMID: 36293269 PMCID: PMC9604028 DOI: 10.3390/ijms232012408] [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: 06/30/2022] [Revised: 10/09/2022] [Accepted: 10/14/2022] [Indexed: 11/16/2022] Open
Abstract
Influenza remains one of the most prevalent viruses circulating amongst humans and has resulted in several pandemics. The prevention and control of H3N2 influenza is complicated by its propensity for evolution, which leads to vaccine mismatch and reduced vaccine efficacies. This study employed the strategy of serial passaging to compare the evolution of the human seasonal influenza strain A/Singapore/G2-31.1/2014(H3N2) in MDCK-SIAT1 versus primary chick embryo fibroblast (CEF) cells. Genetic analysis of the HA, NS1, NA, and PB1 gene segments by Sanger sequencing revealed the presence of specific mutations and a repertoire of viral quasispecies following serial passaging. Most quasispecies were also found in PB1, which exhibited consistently high transversion-to-transition ratios in all five MDCK-SIAT1 passages. Most notably, passage 5 virus harbored the D457G substitution in the HA2 subunit, while passage 3 virus acquired K53Q and Q69H mutations in PB1-F2. An A971 variant leading to a non-synonymous R316Q substitution in PB1 was also identified in MDCK-SIAT1 passages 2 and 4. With an increasing number of passages, the proportion of D457G mutations progressively increased and was associated with larger virus plaque sizes. However, microneutralization assays revealed no significant differences in the neutralizing antibody profiles of human-influenza-immune serum samples against pre-passaged virus and passage 5 virus. In contrast, viable virus was only detected in passage 1 of CEF cells, which gave rise to multiple viral RNA quasispecies. Our findings highlight that serial passaging is able to drive differential adaptation of H3N2 influenza in different host species and may alter viral virulence. More studies are warranted to elucidate the complex relationships between H3N2 virus evolution, viral virulence changes, and low vaccine efficacy.
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Cai L, Xu H, Cui Z. Factors Limiting the Translatability of Rodent Model-Based Intranasal Vaccine Research to Humans. AAPS PharmSciTech 2022; 23:191. [PMID: 35819736 PMCID: PMC9274968 DOI: 10.1208/s12249-022-02330-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 06/09/2022] [Indexed: 12/19/2022] Open
Abstract
The intranasal route of vaccination presents an attractive alternative to parenteral routes and offers numerous advantages, such as the induction of both mucosal and systemic immunity, needle-free delivery, and increased patient compliance. Despite demonstrating promising results in preclinical studies, however, few intranasal vaccine candidates progress beyond early clinical trials. This discrepancy likely stems in part from the limited predictive value of rodent models, which are used frequently in intranasal vaccine research. In this review, we explored the factors that limit the translatability of rodent-based intranasal vaccine research to humans, focusing on the differences in anatomy, immunology, and disease pathology between rodents and humans. We also discussed approaches that minimize these differences and examined alternative animal models that would produce more clinically relevant research.
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Affiliation(s)
- Lucy Cai
- University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, Texas, 75390, USA
| | - Haiyue Xu
- The University of Texas at Austin, College of Pharmacy, Division of Molecular Pharmaceutics and Drug Delivery, 2409 University Ave., A1900, Austin, Texas, 78712, USA
| | - Zhengrong Cui
- The University of Texas at Austin, College of Pharmacy, Division of Molecular Pharmaceutics and Drug Delivery, 2409 University Ave., A1900, Austin, Texas, 78712, USA.
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4
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Yang F, Zhang X, Liu F, Yao H, Wu N, Wu H. Increased virulence of a novel reassortant H1N3 avian influenza virus in mice as a result of adaptive amino acid substitutions. Virus Genes 2022; 58:473-477. [PMID: 35616824 DOI: 10.1007/s11262-022-01911-x] [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: 01/05/2022] [Accepted: 04/29/2022] [Indexed: 11/27/2022]
Abstract
In this study, a novel multiple-gene reassortant H1N3 subtype avian influenza virus (AIV) (A/chicken/Zhejiang/81213/2017, CK81213) was isolated in Eastern China, whose genes were derived from H1 (H1N3), H7 (H7N3 and H7N9), and H10 (H10N3 and H10N8) AIVs. This AIV belongs to the avian Eurasian-lineage and exhibits low pathogenicity. Serial lung-to-lung passages of CK81213 in mice was performed to study the amino acid substitutions potentially related to the adaptation of H1 AIVs in mammals. And the mouse-adapted H1N3 virus showed greater virulence than wild-type H1N3 AIV in mice and the genomic analysis revealed a total of two amino acid substitutions in the PB2 (E627K) and HA (L67V) proteins. Additionally, the results of the animal study indicate that CK81213 could infect mice without prior adaption and become highly pathogenic to mice after continuous passage. Our findings show that routine surveillance of H1 AIVs is important for the prediction of influenza epidemics.
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Affiliation(s)
- Fan Yang
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, and National Clinical Research Center for Infectious Diseases, the First Affiliated Hospital, School of Medicine, Zhejiang University, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, China
| | - Xiaodi Zhang
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, and National Clinical Research Center for Infectious Diseases, the First Affiliated Hospital, School of Medicine, Zhejiang University, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, China
| | - Fumin Liu
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, and National Clinical Research Center for Infectious Diseases, the First Affiliated Hospital, School of Medicine, Zhejiang University, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, China
| | - Hangping Yao
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, and National Clinical Research Center for Infectious Diseases, the First Affiliated Hospital, School of Medicine, Zhejiang University, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, China
| | - Nanping Wu
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, and National Clinical Research Center for Infectious Diseases, the First Affiliated Hospital, School of Medicine, Zhejiang University, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, China
| | - Haibo Wu
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, and National Clinical Research Center for Infectious Diseases, the First Affiliated Hospital, School of Medicine, Zhejiang University, 79 Qingchun Road, Hangzhou, 310003, Zhejiang, China.
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5
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Understanding the Variability of Certain Biological Properties of H1N1pdm09 Influenza Viruses. Vaccines (Basel) 2022; 10:vaccines10030395. [PMID: 35335027 PMCID: PMC8954537 DOI: 10.3390/vaccines10030395] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 02/04/2022] [Accepted: 03/01/2022] [Indexed: 01/10/2023] Open
Abstract
The influenza virus continually evolves because of the high mutation rate, resulting in dramatic changes in its pathogenicity and other biological properties. This study aimed to evaluate the evolution of certain essential properties, understand the connections between them, and find the molecular basis for the manifestation of these properties. To that end, 21 A(H1N1)pdm09 influenza viruses were tested for their pathogenicity and toxicity in a mouse model with a ts/non-ts phenotype manifestation and HA thermal stability. The results demonstrated that, for a strain to have high pathogenicity, it must express a toxic effect, have a non-ts phenotype, and have a thermally stable HA. The ancestor A/California/07/2009 (H1N1)pdm influenza virus expressed the non-ts phenotype, after which the cycling trend of the ts/non-ts phenotype was observed in new strains of A(H1N1)pdm09 influenza viruses, indicating that the ratio of the ts phenotype will increase in the coming years. Of the 21 tested viruses, A/South Africa/3626/2013 had the high pathogenicity in the mouse model. Sequence alignment analysis showed that this virus has three unique mutations in the polymerase complex, two of which are in the PB2 gene and one that is in the PB1 gene. Further study of these mutations might explain the distinguishing pathogenicity.
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Bu L, Chen B, Xing L, Cai X, Liang S, Zhang L, Wang X, Song W. Generation of a pdmH1N1 2018 Influenza A Reporter Virus Carrying a mCherry Fluorescent Protein in the PA Segment. Front Cell Infect Microbiol 2022; 11:827790. [PMID: 35127568 PMCID: PMC8811159 DOI: 10.3389/fcimb.2021.827790] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 12/31/2021] [Indexed: 11/13/2022] Open
Abstract
Influenza A virus (IAV) is a major human pathogen associated with significant morbidity and mortality worldwide. Through serial passage in mice, we generated a recombinant pdmH1N1 2009 IAV, A/Guangdong/GLW/2018 (GLW/18-MA), which encodes an mCherry gene fused to the C-terminal of a polymerase acidic (PA) segment and demonstrated comparable growth kinetics to the wild-type. Nine mutations were identified in the GLW/18-MA genome: PA (I61M, E351G, and G631S), NP (E292G), HA1 (T164I), HA2 (N117S and P160S), NA (W61R), and NEP (K44R). The recombinant IAV reporter expresses mCherry, a red fluorescent protein, at a high level and maintains its genetic integrity after five generations of serial passages in Madin-Darby Canine Kidney cells (MDCK) cells. Moreover, the imaging is noninvasive and permits the monitoring of infection in living mice. Treatment with oseltamivir or baicalin followed by infection with the reporter IAV led to a decrease in fluorescent protein signal in living mice. This result demonstrates that the IAV reporter virus is a powerful tool to study viral pathogenicity and transmission and to develop and evaluate novel anti-viral drugs, inhibitors, and vaccines in the future.
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Affiliation(s)
- Ling Bu
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
- Institute of Integration of Traditional and Western Medicine, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Boqian Chen
- Artemisinin Research Center, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Lei Xing
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
- Institute of Integration of Traditional and Western Medicine, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Xuejun Cai
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
- Institute of Integration of Traditional and Western Medicine, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Shuhua Liang
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
- Institute of Integration of Traditional and Western Medicine, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Liying Zhang
- KingMed School of Laboratory Medicine, Guangzhou Medical University, Guangzhou, China
| | - Xinhua Wang
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
- Institute of Integration of Traditional and Western Medicine, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
- Artemisinin Research Center, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Wenjun Song
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
- Institute of Integration of Traditional and Western Medicine, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
- State Key Laboratory for Emerging Infectious Diseases, Department of Microbiology, and the Research Center of Infection and Immunology, The University of Hong Kong, Hong Kong, Hong Kong SAR, China
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7
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Mergaert AM, Denny MF, Kingstad-Bakke B, Bawadekar M, Bashar SJ, Warner TF, Suresh M, Shelef MA. Peptidylarginine Deiminase 2 in Murine Antiviral and Autoimmune Antibody Responses. J Immunol Res 2022; 2022:5258221. [PMID: 35083342 PMCID: PMC8786467 DOI: 10.1155/2022/5258221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 12/23/2021] [Accepted: 12/24/2021] [Indexed: 11/24/2022] Open
Abstract
The peptidylarginine deiminases (PADs) and the citrullinated proteins that they generate have key roles in innate immunity and rheumatoid arthritis, an inflammatory arthritis with antibodies that target citrullinated proteins. However, the importance of PADs, particularly PAD2, in the adaptive immune response, both normal and pathogenic, is newly emerging. In this study, we evaluated a requirement for PAD2 in the antibody response in collagen-induced arthritis (CIA), a T and B cell-driven murine model of rheumatoid arthritis, and in the protective antibody response to murine influenza infection. Using PAD2-/- and PAD2+/+ mice on the DBA/1J background, we found that PAD2 is required for maximal anti-collagen antibody levels, but not collagen-specific plasma cell numbers, T cell activation or polarization, or arthritis severity in CIA. Also, we found that PAD2 is required not just for normal levels of persistent hemagglutination inhibiting antibodies but also for full protection from lethal influenza rechallenge. Together, these data provide evidence for a novel modest requirement for PAD2 in a normal antiviral antibody response and in an abnormal autoantibody response in inflammatory arthritis.
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Affiliation(s)
- Aisha M. Mergaert
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA
- Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, Madison, WI, USA
| | - Michael F. Denny
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA
| | - Brock Kingstad-Bakke
- Department of Pathobiological Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Mandar Bawadekar
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA
| | - S. Janna Bashar
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA
| | - Thomas F. Warner
- Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, Madison, WI, USA
| | - Marulasiddappa Suresh
- Department of Pathobiological Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Miriam A. Shelef
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA
- William S. Middleton Memorial Veterans Hospital, Madison, WI, USA
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8
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Burton TD, Eyre NS. Applications of Deep Mutational Scanning in Virology. Viruses 2021; 13:1020. [PMID: 34071591 PMCID: PMC8227372 DOI: 10.3390/v13061020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 05/26/2021] [Accepted: 05/26/2021] [Indexed: 12/20/2022] Open
Abstract
Several recently developed high-throughput techniques have changed the field of molecular virology. For example, proteomics studies reveal complete interactomes of a viral protein, genome-wide CRISPR knockout and activation screens probe the importance of every single human gene in aiding or fighting a virus, and ChIP-seq experiments reveal genome-wide epigenetic changes in response to infection. Deep mutational scanning is a relatively novel form of protein science which allows the in-depth functional analysis of every nucleotide within a viral gene or genome, revealing regions of importance, flexibility, and mutational potential. In this review, we discuss the application of this technique to RNA viruses including members of the Flaviviridae family, Influenza A Virus and Severe Acute Respiratory Syndrome Coronavirus 2. We also briefly discuss the reverse genetics systems which allow for analysis of viral replication cycles, next-generation sequencing technologies and the bioinformatics tools that facilitate this research.
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Affiliation(s)
| | - Nicholas S. Eyre
- College of Medicine and Public Health, Flinders University, Bedford Park, SA 5042, Australia;
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Kiseleva I, Rekstin A, Al Farroukh M, Bazhenova E, Katelnikova A, Puchkova L, Rudenko L. Non-Mouse-Adapted H1N1pdm09 Virus as a Model for Influenza Research. Viruses 2020; 12:v12060590. [PMID: 32485821 PMCID: PMC7354452 DOI: 10.3390/v12060590] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 05/21/2020] [Accepted: 05/27/2020] [Indexed: 12/26/2022] Open
Abstract
The number of lung-adapted influenza viruses is limited. Most of them are not antigenically related to current circulating viruses. Viruses similar to recent strains are required for screening modern antiviral compounds and studying new vaccine candidates against novel influenza viruses. The process by which an influenza virus adapts to a new host is rather difficult. The aim of this study was to select a non-adapted current virus whose major biological properties correspond to those of classical lab-adapted viruses. Mice were inoculated intranasally with non-lung-adapted influenza viruses of subtype H1N1pdm09. They were monitored closely for body weight loss, mortality outcomes and gross pathology for 14 days following inoculation, as well as viral replication in lung tissue. Lung-adapted PR8 virus was used as a control. The tested viruses multiplied equally well in the lower respiratory tract of mice without prior adaptation but dramatically differed in lethality; the differences in their toxicity and pathogenicity in mice were established. A/South Africa/3626/2013 (H1N1)pdm09 virus was found to be an appropriate candidate to replace PR8 as a model virus for influenza research. No prior adaptation to the animal model is needed to reach the pathogenicity level of the classical mouse-adapted PR8 virus.
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Affiliation(s)
- Irina Kiseleva
- Department of Virology, Federal State Budgetary Scientific Institution “Institute of Experimental Medicine”, 197376 St Petersburg, Russia; (A.R.); (M.A.F.); (E.B.); (L.P.); (L.R.)
- Correspondence:
| | - Andrey Rekstin
- Department of Virology, Federal State Budgetary Scientific Institution “Institute of Experimental Medicine”, 197376 St Petersburg, Russia; (A.R.); (M.A.F.); (E.B.); (L.P.); (L.R.)
| | - Mohammad Al Farroukh
- Department of Virology, Federal State Budgetary Scientific Institution “Institute of Experimental Medicine”, 197376 St Petersburg, Russia; (A.R.); (M.A.F.); (E.B.); (L.P.); (L.R.)
| | - Ekaterina Bazhenova
- Department of Virology, Federal State Budgetary Scientific Institution “Institute of Experimental Medicine”, 197376 St Petersburg, Russia; (A.R.); (M.A.F.); (E.B.); (L.P.); (L.R.)
| | - Anastasia Katelnikova
- Department of Toxicology and Microbiology, Institute of Preclinical Research Ltd., 188663 St Petersburg, Russia;
| | - Ludmila Puchkova
- Department of Virology, Federal State Budgetary Scientific Institution “Institute of Experimental Medicine”, 197376 St Petersburg, Russia; (A.R.); (M.A.F.); (E.B.); (L.P.); (L.R.)
| | - Larisa Rudenko
- Department of Virology, Federal State Budgetary Scientific Institution “Institute of Experimental Medicine”, 197376 St Petersburg, Russia; (A.R.); (M.A.F.); (E.B.); (L.P.); (L.R.)
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