1
|
Zheng HY, Song TZ, Zheng YT. Immunobiology of COVID-19: Mechanistic and therapeutic insights from animal models. Zool Res 2024; 45:747-766. [PMID: 38894519 PMCID: PMC11298684 DOI: 10.24272/j.issn.2095-8137.2024.062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Accepted: 04/22/2024] [Indexed: 06/21/2024] Open
Abstract
The distribution of the immune system throughout the body complicates in vitro assessments of coronavirus disease 2019 (COVID-19) immunobiology, often resulting in a lack of reproducibility when extrapolated to the whole organism. Consequently, developing animal models is imperative for a comprehensive understanding of the pathology and immunology of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. This review summarizes current progress related to COVID-19 animal models, including non-human primates (NHPs), mice, and hamsters, with a focus on their roles in exploring the mechanisms of immunopathology, immune protection, and long-term effects of SARS-CoV-2 infection, as well as their application in immunoprevention and immunotherapy of SARS-CoV-2 infection. Differences among these animal models and their specific applications are also highlighted, as no single model can fully encapsulate all aspects of COVID-19. To effectively address the challenges posed by COVID-19, it is essential to select appropriate animal models that can accurately replicate both fatal and non-fatal infections with varying courses and severities. Optimizing animal model libraries and associated research tools is key to resolving the global COVID-19 pandemic, serving as a robust resource for future emerging infectious diseases.
Collapse
Affiliation(s)
- Hong-Yi Zheng
- State Key Laboratory of Genetic Evolution & Animal Models, KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, Center for Biosafety Mega-Science, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China
| | - Tian-Zhang Song
- State Key Laboratory of Genetic Evolution & Animal Models, KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, Center for Biosafety Mega-Science, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China
| | - Yong-Tang Zheng
- State Key Laboratory of Genetic Evolution & Animal Models, KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, Center for Biosafety Mega-Science, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China
- National Resource Center for Non-Human Primates, National Research Facility for Phenotypic & Genetic Analysis of Model Animals (Primate Facility), Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650107, China. E-mail:
| |
Collapse
|
2
|
Pal R, Ferrari MG, Honda-Okubo Y, Wattay L, Caple J, Navarrete J, Andersen H, Petrovsky N. Study of immunogenicity and efficacy against Omicron BA.5 of recombinant protein-based COVID-19 vaccine delivered by intramuscular and mucosal routes in nonhuman primates. Vaccine 2024; 42:1122-1135. [PMID: 38262808 DOI: 10.1016/j.vaccine.2024.01.034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 12/21/2023] [Accepted: 01/10/2024] [Indexed: 01/25/2024]
Abstract
BACKGROUND With SARS-CoV-2 continuing to evolve, there is a need to adapt COVID-19 vaccines to enhance mucosal immunity and better address immune-evasive variants. This pilot study was performed in mice and rhesus macaques to compare Advax-adjuvanted monovalent and bivalent recombinant spike protein vaccines, including when delivered via a combination of intramuscular (IM) and intrapulmonary (IPM) or oral routes. METHODS Mice were first used to compare the immunogenicity of monovalent and bivalent vaccines containing a variety of spike protein variants. Then, rhesus macaques (n = 23) were divided into 5 groups to receive COVID-19 vaccines via different routes. Clinical signs, local vaccination site reactions, body weight, food consumption, serum, alveolar lavage, nasal and oral antibody levels, and nasal and alveolar lavage virus loads were assessed in response to a heterologous Omicron BA.5 virus challenge. RESULTS The Wuhan + Mu bivalent vaccine gave the most broadly cross-neutralizing antibody responses. Robust serum neutralizing antibodies against Wuhan, Delta and Lambda variants were obtained, but BA.5 neutralizing antibodies were not detectable pre-challenge. Overall, the IM x3 and the IM x2 plus oral x2 vaccines delivered the best protection, with reduced lung virus load versus unimmunized controls across Days 2, 4 and 7. CONCLUSIONS Advax-adjuvanted monovalent or bivalent recombinant spike protein vaccines given via parenteral and/or mucosal routes protected against a heterologous BA.5 challenge, despite absent serum BA.5 neutralizing antibody, pre-challenge. The possibility of using an oral Advax-adjuvanted protein booster to provide broad protection against newer SARS-CoV-2 variants warrants further investigation.
Collapse
Affiliation(s)
- Ranajit Pal
- BIOQUAL, Inc., 9600 Medical Center Drive, Rockville, MD 20850-3336, USA.
| | | | | | - Lauren Wattay
- BIOQUAL, Inc., 9600 Medical Center Drive, Rockville, MD 20850-3336, USA.
| | - Jesica Caple
- BIOQUAL, Inc., 9600 Medical Center Drive, Rockville, MD 20850-3336, USA.
| | - Jennifer Navarrete
- BIOQUAL, Inc., 9600 Medical Center Drive, Rockville, MD 20850-3336, USA.
| | - Hanne Andersen
- BIOQUAL, Inc., 9600 Medical Center Drive, Rockville, MD 20850-3336, USA.
| | - Nikolai Petrovsky
- Vaxine Pty Ltd., 11-13 Walkley Avenue, Warradale, SA 5046, Australia.
| |
Collapse
|
3
|
Sung JCC, Lai NCY, Wu KC, Choi MC, Ma CHY, Lin J, Kuok CN, Leong WL, Lam WK, Hamied YK, Lam DMK, Sze ETP, Kwong KWY. Safety and Immunogenicity of Inactivated Bacillus subtilis Spores as a Heterologous Antibody Booster for COVID-19 Vaccines. Vaccines (Basel) 2022; 10:1014. [PMID: 35891178 PMCID: PMC9322707 DOI: 10.3390/vaccines10071014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 06/21/2022] [Accepted: 06/21/2022] [Indexed: 12/04/2022] Open
Abstract
The coronavirus diseases 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections have threatened the world for more than 2 years. Multiple vaccine candidates have been developed and approved for emergency use by specific markets, but multiple doses are required to maintain the antibody level. Preliminary safety and immunogenicity data about an oral dose vaccine candidate using recombinant Bacillus subtilis in healthy adults were reported previously from an investigator-initiated trial in Hong Kong. Additional data are required in order to demonstrate the safety and efficacy of the candidate as a heterologous booster in vaccinated recipients. In an ongoing, placebo-controlled, observer-blinded, fixed dose, investigator-initiated trial conducted in the Macau, we randomly assigned healthy adults, 21 to 62 years of age to receive either placebo or a Bacillus subtilis oral dose vaccine candidate, which expressed the spike protein receptor binding domain of SARS-CoV-2 on the spore surface. The primary outcome was safety (e.g., local and systemic reactions and adverse events); immunogenicity was a secondary outcome. For both the active vaccine and placebo, participants received three courses in three consecutive days. A total of 16 participants underwent randomization: 9 participants received vaccine and 7 received placebo. No observable local or systemic side-effect was reported. In both younger and older adults receiving placebo, the neutralizing antibody levels were gradually declining, whereas the participants receiving the antibody booster showed an increase in neutralizing antibody level.
Collapse
Affiliation(s)
- Johnny Chun-Chau Sung
- Research Department, DreamTec Cytokines Limited, Hong Kong, China; (J.C.-C.S.); (N.C.-Y.L.); (K.-C.W.); (M.-C.C.); (C.H.-Y.M.); (J.L.)
- Oristry BioTech (HK) Limited, Hong Kong, China
- Meserna Therapeutic (HK) Limited, Hong Kong, China
- L&L Immunotherapy Company Limited, Hong Kong, China;
| | - Nelson Cheuk-Yin Lai
- Research Department, DreamTec Cytokines Limited, Hong Kong, China; (J.C.-C.S.); (N.C.-Y.L.); (K.-C.W.); (M.-C.C.); (C.H.-Y.M.); (J.L.)
- Oristry BioTech (HK) Limited, Hong Kong, China
- Meserna Therapeutic (HK) Limited, Hong Kong, China
- L&L Immunotherapy Company Limited, Hong Kong, China;
| | - Kam-Chau Wu
- Research Department, DreamTec Cytokines Limited, Hong Kong, China; (J.C.-C.S.); (N.C.-Y.L.); (K.-C.W.); (M.-C.C.); (C.H.-Y.M.); (J.L.)
| | - Man-Chung Choi
- Research Department, DreamTec Cytokines Limited, Hong Kong, China; (J.C.-C.S.); (N.C.-Y.L.); (K.-C.W.); (M.-C.C.); (C.H.-Y.M.); (J.L.)
| | - Chloe Ho-Yi Ma
- Research Department, DreamTec Cytokines Limited, Hong Kong, China; (J.C.-C.S.); (N.C.-Y.L.); (K.-C.W.); (M.-C.C.); (C.H.-Y.M.); (J.L.)
| | - Jayman Lin
- Research Department, DreamTec Cytokines Limited, Hong Kong, China; (J.C.-C.S.); (N.C.-Y.L.); (K.-C.W.); (M.-C.C.); (C.H.-Y.M.); (J.L.)
- L&L Immunotherapy Company Limited, Hong Kong, China;
| | - Cheong-Nang Kuok
- Macao Greater Bay Area Association of Healthcare Providers, Macau 999078, China; (C.-N.K.); (W.-L.L.); (W.-K.L.)
| | - Wai-Leng Leong
- Macao Greater Bay Area Association of Healthcare Providers, Macau 999078, China; (C.-N.K.); (W.-L.L.); (W.-K.L.)
| | - Weng-Kei Lam
- Macao Greater Bay Area Association of Healthcare Providers, Macau 999078, China; (C.-N.K.); (W.-L.L.); (W.-K.L.)
| | | | - Dominic Man-Kit Lam
- L&L Immunotherapy Company Limited, Hong Kong, China;
- Torsten Wiesel International Research Institute, Sichuan University, Chengdu 610064, China
| | - Eric Tung-Po Sze
- School of Science and Technology, Hong Kong Metropolitan University, Hong Kong, China;
| | - Keith Wai-Yeung Kwong
- Research Department, DreamTec Cytokines Limited, Hong Kong, China; (J.C.-C.S.); (N.C.-Y.L.); (K.-C.W.); (M.-C.C.); (C.H.-Y.M.); (J.L.)
- Oristry BioTech (HK) Limited, Hong Kong, China
- Meserna Therapeutic (HK) Limited, Hong Kong, China
- L&L Immunotherapy Company Limited, Hong Kong, China;
| |
Collapse
|
4
|
Goławski M, Lewandowski P, Jabłońska I, Delijewski M. The Reassessed Potential of SARS-CoV-2 Attenuation for COVID-19 Vaccine Development—A Systematic Review. Viruses 2022; 14:v14050991. [PMID: 35632736 PMCID: PMC9146402 DOI: 10.3390/v14050991] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 04/29/2022] [Accepted: 05/03/2022] [Indexed: 11/16/2022] Open
Abstract
Live-attenuated SARS-CoV-2 vaccines received relatively little attention during the COVID-19 pandemic. Despite this, several methods of obtaining attenuated coronaviruses are known. In this systematic review, the strategies of coronavirus attenuation, which may potentially be applied to SARS-CoV-2, were identified. PubMed, Scopus, Web of Science and Embase databases were searched to identify relevant articles describing attenuating mutations tested in vivo. In case of coronaviruses other than SARS-CoV-2, sequence alignment was used to exclude attenuating mutations that cannot be applied to SARS-CoV-2. Potential immunogenicity, safety and efficacy of the attenuated SARS-CoV-2 vaccine were discussed based on animal studies data. A total of 27 attenuation strategies, used to create 101 different coronaviruses, have been described in 56 eligible articles. The disruption of the furin cleavage site in the SARS-CoV-2 spike protein was identified as the most promising strategy. The replacement of core sequences of transcriptional regulatory signals, which prevents recombination with wild-type viruses, also appears particularly advantageous. Other important attenuating mutations encompassed mostly the prevention of evasion of innate immunity. Sufficiently attenuated coronaviruses typically caused no meaningful disease in susceptible animals and protected them from challenges with virulent virus. This indicates that attenuated COVID-19 vaccines may be considered as a potential strategy to fight the threat posed by SARS-CoV-2.
Collapse
Affiliation(s)
- Marcin Goławski
- Department of Pharmacology, Faculty of Medical Sciences in Zabrze, Medical University of Silesia, 41-808 Katowice, Poland; (P.L.); (M.D.)
- Correspondence:
| | - Piotr Lewandowski
- Department of Pharmacology, Faculty of Medical Sciences in Zabrze, Medical University of Silesia, 41-808 Katowice, Poland; (P.L.); (M.D.)
| | - Iwona Jabłońska
- Department of Biophysics, Faculty of Medical Sciences in Zabrze, Medical University of Silesia, 41-808 Katowice, Poland;
| | - Marcin Delijewski
- Department of Pharmacology, Faculty of Medical Sciences in Zabrze, Medical University of Silesia, 41-808 Katowice, Poland; (P.L.); (M.D.)
| |
Collapse
|
5
|
Focosi D, Maggi F, Casadevall A. Mucosal Vaccines, Sterilizing Immunity, and the Future of SARS-CoV-2 Virulence. Viruses 2022; 14:187. [PMID: 35215783 PMCID: PMC8878800 DOI: 10.3390/v14020187] [Citation(s) in RCA: 53] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 01/15/2022] [Accepted: 01/17/2022] [Indexed: 02/01/2023] Open
Abstract
Sterilizing immunity after vaccination is desirable to prevent the spread of infection from vaccinees, which can be especially dangerous in hospital settings while managing frail patients. Sterilizing immunity requires neutralizing antibodies at the site of infection, which for respiratory viruses such as SARS-CoV-2 implies the occurrence of neutralizing IgA in mucosal secretions. Systemic vaccination by intramuscular delivery induces no or low-titer neutralizing IgA against vaccine antigens. Mucosal priming or boosting, is needed to provide sterilizing immunity. On the other side of the coin, sterilizing immunity, by zeroing interhuman transmission, could confine SARS-CoV-2 in animal reservoirs, preventing spontaneous attenuation of virulence in humans as presumably happened with the endemic coronaviruses. We review here the pros and cons of each vaccination strategy, the current mucosal SARS-CoV-2 vaccines under development, and their implications for public health.
Collapse
Affiliation(s)
- Daniele Focosi
- North-Western Tuscany Blood Bank, Pisa University Hospital, 56124 Pisa, Italy
| | - Fabrizio Maggi
- Department of Medicine and Surgery, University of Insubria, 21100 Varese, Italy;
| | - Arturo Casadevall
- Department of Medicine, Johns Hopkins School of Public Health and School of Medicine, Baltimore, MD 21218, USA;
| |
Collapse
|
6
|
Expression of SARS-CoV-2 Spike Protein Receptor Binding Domain on Recombinant B. subtilis on Spore Surface: A Potential COVID-19 Oral Vaccine Candidate. Vaccines (Basel) 2021; 10:vaccines10010002. [PMID: 35062663 PMCID: PMC8780001 DOI: 10.3390/vaccines10010002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 12/13/2021] [Accepted: 12/19/2021] [Indexed: 12/11/2022] Open
Abstract
Various types of vaccines, such as mRNA, adenovirus, and inactivated virus by injection, have been developed to prevent SARS-CoV-2 infection. Although some of them have already been approved under the COVID-19 pandemic, various drawbacks, including severe side effects and the requirement for sub-zero temperature storage, may hinder their applications. Bacillus subtilis (B. subtilis) is generally recognized as a safe and endotoxin-free Gram-positive bacterium that has been extensively employed as a host for the expression of recombinant proteins. Its dormant spores are extraordinarily resistant to the harsh environment in the gastrointestinal tract. This feature makes it an ideal carrier for oral administration in resisting this acidic environment and for release in the intestine. In this study, an engineered B. subtilis spore expressing the SARS-CoV-2 spike protein receptor binding domain (sRBD) on the spore surface was developed. In a pilot test, no adverse health event was observed in either mice or healthy human volunteers after three oral courses of B. subtilis spores. Significant increases in neutralizing antibody against sRBD, in both mice and human volunteers, after oral administration were also found. These findings may enable the further clinical developments of B. subtilis spores as an oral vaccine candidate against COVID-19 in the future.
Collapse
|