1
|
Jones RP, Ponomarenko A. Roles for Pathogen Interference in Influenza Vaccination, with Implications to Vaccine Effectiveness (VE) and Attribution of Influenza Deaths. Infect Dis Rep 2022; 14:710-758. [PMID: 36286197 PMCID: PMC9602062 DOI: 10.3390/idr14050076] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 09/15/2022] [Accepted: 09/15/2022] [Indexed: 08/29/2023] Open
Abstract
Pathogen interference is the ability of one pathogen to alter the course and clinical outcomes of infection by another. With up to 3000 species of human pathogens the potential combinations are vast. These combinations operate within further immune complexity induced by infection with multiple persistent pathogens, and by the role which the human microbiome plays in maintaining health, immune function, and resistance to infection. All the above are further complicated by malnutrition in children and the elderly. Influenza vaccination offers a measure of protection for elderly individuals subsequently infected with influenza. However, all vaccines induce both specific and non-specific effects. The specific effects involve stimulation of humoral and cellular immunity, while the nonspecific effects are far more nuanced including changes in gene expression patterns and production of small RNAs which contribute to pathogen interference. Little is known about the outcomes of vaccinated elderly not subsequently infected with influenza but infected with multiple other non-influenza winter pathogens. In this review we propose that in certain years the specific antigen mix in the seasonal influenza vaccine inadvertently increases the risk of infection from other non-influenza pathogens. The possibility that vaccination could upset the pathogen balance, and that the timing of vaccination relative to the pathogen balance was critical to success, was proposed in 2010 but was seemingly ignored. Persons vaccinated early in the winter are more likely to experience higher pathogen interference. Implications to the estimation of vaccine effectiveness and influenza deaths are discussed.
Collapse
Affiliation(s)
- Rodney P Jones
- Healthcare Analysis and Forecasting, Wantage OX12 0NE, UK
| | - Andrey Ponomarenko
- Department of Biophysics, Informatics and Medical Instrumentation, Odessa National Medical University, Valikhovsky Lane 2, 65082 Odessa, Ukraine
| |
Collapse
|
2
|
Hosseini-Moghaddam SM, He S, Calzavara A, Campitelli MA, Kwong JC. Association of Influenza Vaccination With SARS-CoV-2 Infection and Associated Hospitalization and Mortality Among Patients Aged 66 Years or Older. JAMA Netw Open 2022; 5:e2233730. [PMID: 36169955 PMCID: PMC9520345 DOI: 10.1001/jamanetworkopen.2022.33730] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 08/11/2022] [Indexed: 11/14/2022] Open
Abstract
Importance Vaccine effectiveness studies have rarely implemented strategies to reduce the healthy vaccinee bias arising from differences in health care-seeking behavior between vaccinated and unvaccinated individuals. Although previous observational studies suggest that influenza vaccination is associated with a reduced risk of SARS-CoV-2-associated outcomes, the healthy vaccinee bias may have led to overestimating the vaccination effect. Objective To estimate the association between influenza vaccination and SARS-CoV-2-associated outcomes. Design, Setting, and Participants This cohort study was conducted over 2 consecutive influenza vaccination campaigns (2019-2020 and 2020-2021), owing to the substantial COVID-19 burden and the greater validity of influenza vaccination data in the studied age group. The study population included community-dwelling adults aged 66 years or older in Ontario, Canada. Exposure Influenza vaccination for a given season. Main Outcomes and Measures The outcomes of interest included SARS-CoV-2 infection, SARS-CoV-2-associated hospitalization, SARS-CoV-2-associated death, and a composite of SARS-CoV-2-associated hospitalization or death. Cox proportional hazards models were used to measure the association between influenza vaccination and SARS-CoV-2-associated outcomes, censoring individuals who moved into long-term care, received COVID-19 vaccines, or died before the observation period end date. Primary care periodic health examinations (PHEs) were explored as a negative tracer exposure (ie, no association expected with SARS-CoV-2 outcomes) and as an effect modifier of the association between influenza vaccination and SARS-CoV-2 outcomes. Results Of 2 922 449 individuals aged 66 years or older (54.2% female) living in Ontario, 2 279 805 were included in the study. Among these, 1 234 647 (54.2%) were female and 1 045 158 (45.8%) were male; their mean (SD) age was 75.08 (7.21) years. Those who had received influenza vaccination exhibited a lower incidence of SARS-CoV-2 infection than unvaccinated individuals for the 2019-2020 cohort (adjusted hazards ratio [aHR], 0.78; 95% CI, 0.73-0.84) and the 2020-2021 cohort (aHR, 0.76; 95% CI, 0.74-0.78). This association was also observed for SARS-CoV-2-associated hospitalization or death (2019-2020: aHR, 0.83; 95% CI, 0.74-0.92; 2020-2021: aHR, 0.66; 95% CI, 0.63-0.70). Similarly, undergoing a PHE was also associated with a lower incidence of SARS-CoV-2 infection (aHR, 0.85; 95% CI, 0.78-0.91) and SARS-CoV-2-associated hospitalization or death (aHR, 0.80; 95% CI, 0.70-0.90), and modified the association between influenza vaccination and SARS-CoV-2 infection for vaccinated individuals who underwent PHE (aHR, 0.62; 95% CI, 0.52-0.74) and for vaccinated individuals who did not undergo PHE (aHR, 0.81; 95% CI, 0.76-0.87), and also SARS-CoV-2-associated hospitalization or death in vaccinated individuals who underwent PHE (aHR, 0.66; 95% CI, 0.49-0.88) and vaccinated individuals who did not undergo PHE (aHR, 0.85, 95% CI, 0.76-0.95). Conclusions and Relevance The findings of this cohort study suggest that undergoing a PHE may at least partially modify the association between influenza vaccination and SARS-CoV-2-associated outcomes in individuals aged 66 years or older, providing evidence of the healthy vaccinee bias that may affect vaccine effectiveness studies.
Collapse
Affiliation(s)
- Seyed M. Hosseini-Moghaddam
- ICES, Toronto, Ontario, Canada
- Ajmera Transplant Centre, University Health Network, Toronto, Ontario, Canada
- Division of Infectious Diseases, Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Siyi He
- ICES, Toronto, Ontario, Canada
| | | | | | - Jeffrey C. Kwong
- ICES, Toronto, Ontario, Canada
- Public Health Ontario, Toronto, Canada
- Department of Family and Community Medicine, University of Toronto, Toronto, Ontario, Canada
- Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada
- Centre for Vaccine Preventable Diseases, University of Toronto, Toronto, Ontario, Canada
| |
Collapse
|
3
|
Kayhan S, Hepsen S, Kalkisim HK, Sendur IN, Altay FA, Yalcindag A. The evaluation of pancreas β-cell autoantibodies in non-diabetic COVID-19 patients. ARCHIVES OF ENDOCRINOLOGY AND METABOLISM 2022; 66:459-465. [PMID: 35657130 PMCID: PMC10697637 DOI: 10.20945/2359-3997000000498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 04/15/2022] [Indexed: 06/15/2023]
Abstract
Objective This study aims to evaluate potential pancreas endocrine damage due to SARS-CoV-2 by measuring β-cell autoantibodies in COVID-19 patients. Subjects and methods Between June and July 2020, 95 inpatients with a positive COVID-19 test result after polymerase-chain-reaction (PCR) and who met the inclusion criteria were enrolled in our study. Laboratory parameters that belong to glucose metabolism and β-cell autoantibodies, including anti-islet, anti-glutamic acid decarboxylase, and anti-insulin autoantibodies, were measured. β-cell autoantibodies levels of the patients were measured during COVID-19 diagnosis. Positive results were reevaluated in the 3rd month of control. Results In the initial evaluation, 4 (4.2%) patients were positive for anti-islet autoantibody. Only one (1.1%) patient was positive for anti-glutamic acid decarboxylase autoantibody. No patient had positive results for anti-insulin autoantibody. FPG, HbA1c, and C-peptide levels were similar in patients who were split into groups regarding the initial positive or negative status of anti-islet and anti-GAD autoantibodies (p>0.05). In the 3rd month after the initial measurements, anti-islet autoantibody positivity of 2 (50%) of 4 patients and anti-glutamic acid decarboxylase positivity of 1 (100%) patient were persistent. Finally, 3 (3.1%) patients in the whole group were positive for anti-islet autoantibody in the 3rd month of control. No difference was determined between the initial and the 3rd month of parameters of glucose metabolism. Conclusion Following an ongoing autoantibody positivity in the present study brings the mind that SARS-CoV-2 may be responsible for the diabetogenic effect. Clinicians should be aware of autoantibody-positive DM as a potential autoimmune complication in patients with SARS-CoV-2.
Collapse
Affiliation(s)
- Sanem Kayhan
- Department of Internal Medicine, University of Health Sciences, Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey,
| | - Sema Hepsen
- Department of Endocrinology and Metabolism, University of Health Sciences, Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey
| | - Hatice Kozan Kalkisim
- Department of Internal Medicine, University of Health Sciences, Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey
| | - Ibrahim Nahit Sendur
- Department of Internal Medicine, University of Health Sciences, Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey
| | - Fatma Aybala Altay
- Department of Infectious Diseases and Clinical Microbiology, University of Health Sciences, Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey
| | - Ali Yalcindag
- Department of Clinical Biochemistry, University of Health Sciences, Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey
| |
Collapse
|
4
|
Homologies between SARS-CoV-2 and allergen proteins may direct T cell-mediated heterologous immune responses. Sci Rep 2021; 11:4792. [PMID: 33637823 PMCID: PMC7910599 DOI: 10.1038/s41598-021-84320-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 02/15/2021] [Indexed: 01/30/2023] Open
Abstract
The outbreak of the new severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is a public health emergency. Asthma does not represent a risk factor for COVID-19 in several published cohorts. We hypothesized that the SARS-CoV-2 proteome contains T cell epitopes, which are potentially cross-reactive to allergen epitopes. We aimed at identifying homologous peptide sequences by means of two distinct complementary bioinformatics approaches. Pipeline 1 included prediction of MHC Class I and Class II epitopes contained in the SARS-CoV-2 proteome and allergens along with alignment and elaborate ranking approaches. Pipeline 2 involved alignment of SARS-CoV-2 overlapping peptides with known allergen-derived T cell epitopes. Our results indicate a large number of MHC Class I epitope pairs including known as well as de novo predicted allergen T cell epitopes with high probability for cross-reactivity. Allergen sources, such as Aspergillus fumigatus, Phleum pratense and Dermatophagoides species are of particular interest due to their association with multiple cross-reactive candidate peptides, independently of the applied bioinformatic approach. In contrast, peptides derived from food allergens, as well as MHC class II epitopes did not achieve high in silico ranking and were therefore not further investigated. Our findings warrant further experimental confirmation along with examination of the functional importance of such cross-reactive responses.
Collapse
|
5
|
Balz K, Chen M, Kaushik A, Cemic F, Heger V, Renz H, Nadeau K, Skevaki C. Homologies between SARS-CoV-2 and allergen proteins may direct T cell-mediated heterologous immune responses. RESEARCH SQUARE 2020:rs.3.rs-86873. [PMID: 33052330 PMCID: PMC7553154 DOI: 10.21203/rs.3.rs-86873/v1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The outbreak of the new Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is a public health emergency. Asthma does not represent a risk factor for COVID-19 in several published cohorts. We hypothesized that the SARS-CoV-2 proteome contains T cell epitopes, which are potentially cross-reactive to allergen epitopes. We aimed at identifying homologous peptide sequences by means of two distinct complementary bioinformatics approaches. Pipeline 1 included prediction of MHC Class I and Class II epitopes contained in the SARS-CoV-2 proteome and allergens along with alignment and elaborate ranking approaches. Pipeline 2 involved alignment of SARS-CoV-2 overlapping peptides with known allergen-derived T cell epitopes. Our results indicate a large number of MHC Class I epitope pairs including known as well as de novo predicted allergen T cell epitopes with high probability for cross-reactivity. Allergen sources, such as Aspergillus fumigatus , Phleum pratense and Dermatophagoides species are of particular interest due to their association with multiple cross-reactive candidate peptides, independently of the applied bioinformatic approach. In contrast, peptides derived from food allergens, as well as MHC class II epitopes did not achieve high in silico ranking and were therefore not further investigated. Our findings warrant further experimental confirmation along with examination of the functional importance of such cross-reactive responses.
Collapse
Affiliation(s)
- Kathrin Balz
- Institute of Laboratory Medicine, Universities of Giessen and Marburg Lung Center (UGMLC), Philipps University Marburg, German Center for Lung Research (DZL), Marburg, Germany
| | - Meng Chen
- Sean N. Parker Center for Allergy and Asthma Research at Stanford University and Division of Pulmonary, Allergy & Critical Care Medicine, Stanford, CA, USA
| | - Abhinav Kaushik
- Sean N. Parker Center for Allergy and Asthma Research at Stanford University and Division of Pulmonary, Allergy & Critical Care Medicine, Stanford, CA, USA
| | - Franz Cemic
- TH Mittelhessen, Department of Computer Science, University of Applied Sciences Gießen, Hessen, Deutschland
| | - Vanessa Heger
- TH Mittelhessen, Department of Computer Science, University of Applied Sciences Gießen, Hessen, Deutschland
| | - Harald Renz
- Institute of Laboratory Medicine, Universities of Giessen and Marburg Lung Center (UGMLC), Philipps University Marburg, German Center for Lung Research (DZL), Marburg, Germany
| | - Kari Nadeau
- Sean N. Parker Center for Allergy and Asthma Research at Stanford University and Division of Pulmonary, Allergy & Critical Care Medicine, Stanford, CA, USA
| | - Chrysanthi Skevaki
- Institute of Laboratory Medicine, Universities of Giessen and Marburg Lung Center (UGMLC), Philipps University Marburg, German Center for Lung Research (DZL), Marburg, Germany
| |
Collapse
|
6
|
Najjar S, Najjar A, Chong DJ, Pramanik BK, Kirsch C, Kuzniecky RI, Pacia SV, Azhar S. Central nervous system complications associated with SARS-CoV-2 infection: integrative concepts of pathophysiology and case reports. J Neuroinflammation 2020; 17:231. [PMID: 32758257 PMCID: PMC7406702 DOI: 10.1186/s12974-020-01896-0] [Citation(s) in RCA: 162] [Impact Index Per Article: 40.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 07/14/2020] [Indexed: 02/06/2023] Open
Abstract
Coronavirus disease 2019 (COVID-19) is a highly infectious pandemic caused by a novel coronavirus called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It frequently presents with unremitting fever, hypoxemic respiratory failure, and systemic complications (e.g., gastrointestinal, renal, cardiac, and hepatic involvement), encephalopathy, and thrombotic events. The respiratory symptoms are similar to those accompanying other genetically related beta-coronaviruses (CoVs) such as severe acute respiratory syndrome CoV (SARS-CoV) and Middle East Respiratory Syndrome CoV (MERS-CoV). Hypoxemic respiratory symptoms can rapidly progress to Acute Respiratory Distress Syndrome (ARDS) and secondary hemophagocytic lymphohistiocytosis, leading to multi-organ system dysfunction syndrome. Severe cases are typically associated with aberrant and excessive inflammatory responses. These include significant systemic upregulation of cytokines, chemokines, and pro-inflammatory mediators, associated with increased acute-phase proteins (APPs) production such as hyperferritinemia and elevated C-reactive protein (CRP), as well as lymphocytopenia. The neurological complications of SARS-CoV-2 infection are high among those with severe and critical illnesses. This review highlights the central nervous system (CNS) complications associated with COVID-19 attributed to primary CNS involvement due to rare direct neuroinvasion and more commonly secondary CNS sequelae due to exuberant systemic innate-mediated hyper-inflammation. It also provides a theoretical integration of clinical and experimental data to elucidate the pathogenesis of these disorders. Specifically, how systemic hyper-inflammation provoked by maladaptive innate immunity may impair neurovascular endothelial function, disrupt BBB, activate CNS innate immune signaling pathways, and induce para-infectious autoimmunity, potentially contributing to the CNS complications associated with SARS-CoV-2 infection. Direct viral infection of the brain parenchyma causing encephalitis, possibly with concurrent neurovascular endotheliitis and CNS renin angiotensin system (RAS) dysregulation, is also reviewed.
Collapse
Affiliation(s)
- Souhel Najjar
- Department of Neurology, Zucker School of Medicine at Hofstra/Northwell, Lenox Hill Hospital, New York, NY, USA.
- Department of Neurology, Zucker School of Medicine at Hofstra/Northwell, North Shore University Hospital, Manhasset, NY, USA.
| | - Amanda Najjar
- Department of Neurology, Zucker School of Medicine at Hofstra/Northwell, Lenox Hill Hospital, New York, NY, USA
- Ferkauf Graduate School of Psychology, Yeshiva University, Bronx, NY, USA
| | - Derek J Chong
- Department of Neurology, Zucker School of Medicine at Hofstra/Northwell, Lenox Hill Hospital, New York, NY, USA
| | - Bidyut K Pramanik
- Department of Radiology, Zucker School of Medicine at Hofstra/Northwell, Lenox Hill Hospital, New York, NY, USA
| | - Claudia Kirsch
- Department of Radiology, Zucker School of Medicine at Hofstra/Northwell, North Shore University Hospital, Manhasset, NY, USA
| | - Ruben I Kuzniecky
- Department of Neurology, Zucker School of Medicine at Hofstra/Northwell, Lenox Hill Hospital, New York, NY, USA
| | - Steven V Pacia
- Department of Neurology, Zucker School of Medicine at Hofstra/Northwell, Lenox Hill Hospital, New York, NY, USA
- Department of Neurology, Zucker School of Medicine at Hofstra/Northwell, North Shore University Hospital, Manhasset, NY, USA
| | - Salman Azhar
- Department of Neurology, Zucker School of Medicine at Hofstra/Northwell, Lenox Hill Hospital, New York, NY, USA
| |
Collapse
|
7
|
Somasundaram NP, Ranathunga I, Ratnasamy V, Wijewickrama PSA, Dissanayake HA, Yogendranathan N, Gamage KKK, de Silva NL, Sumanatilleke M, Katulanda P, Grossman AB. The Impact of SARS-Cov-2 Virus Infection on the Endocrine System. J Endocr Soc 2020; 4:bvaa082. [PMID: 32728654 PMCID: PMC7337839 DOI: 10.1210/jendso/bvaa082] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 06/17/2020] [Indexed: 02/06/2023] Open
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus has spread across the globe rapidly causing an unprecedented pandemic. Because of the novelty of the disease, the possible impact on the endocrine system is not clear. To compile a mini-review describing possible endocrine consequences of SARS-CoV-2 infection, we performed a literature survey using the key words Covid-19, Coronavirus, SARS CoV-1, SARS Cov-2, Endocrine, and related terms in medical databases including PubMed, Google Scholar, and MedARXiv from the year 2000. Additional references were identified through manual screening of bibliographies and via citations in the selected articles. The literature review is current until April 28, 2020. In light of the literature, we discuss SARS-CoV-2 and explore the endocrine consequences based on the experience with structurally-similar SARS-CoV-1. Studies from the SARS -CoV-1 epidemic have reported variable changes in the endocrine organs. SARS-CoV-2 attaches to the ACE2 system in the pancreas causing perturbation of insulin production resulting in hyperglycemic emergencies. In patients with preexisting endocrine disorders who develop COVID-19, several factors warrant management decisions. Hydrocortisone dose adjustments are required in patients with adrenal insufficiency. Identification and management of critical illness-related corticosteroid insufficiency is crucial. Patients with Cushing syndrome may have poorer outcomes because of the associated immunodeficiency and coagulopathy. Vitamin D deficiency appears to be associated with increased susceptibility or severity to SARS-CoV-2 infection, and replacement may improve outcomes. Robust strategies required for the optimal management of endocrinopathies in COVID-19 are discussed extensively in this mini-review.
Collapse
Affiliation(s)
| | - Ishara Ranathunga
- Diabetes and Endocrine Unit, National Hospital of Sri Lanka, Colombo, Sri Lanka
| | - Vithiya Ratnasamy
- University Medical Unit, National Hospital of Sri Lanka, Colombo, Sri Lanka
| | | | | | | | | | - Nipun Lakshitha de Silva
- Diabetes and Endocrine Unit, National Hospital of Sri Lanka, Colombo, Sri Lanka.,Department of Clinical Sciences, Faculty of Medicine, General Sir John Kotelawala Defence University, Sri Lanka, Rathmalana, Sri Lanka
| | | | - Prasad Katulanda
- University Medical Unit, National Hospital of Sri Lanka, Colombo, Sri Lanka.,Diabetes Research Unit, Department of Clinical Medicine, Faculty of Medicine, University of Colombo, Sri Lanka, Colombo, Sri Lanka
| | - Ashley Barry Grossman
- Oxford Centre for Diabetes, Endocrinology and Metabolism, Churchill Hospital, University of Oxford, London, UK.,Centre for Endocrinology, Barts and the London School of Medicine, Queen Mary University of London, Oxford, UK
| |
Collapse
|
8
|
Yaqinuddin A. Cross-immunity between respiratory coronaviruses may limit COVID-19 fatalities. Med Hypotheses 2020; 144:110049. [PMID: 32758887 PMCID: PMC7326438 DOI: 10.1016/j.mehy.2020.110049] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Accepted: 06/25/2020] [Indexed: 01/09/2023]
Abstract
Of the seven coronaviruses associated with disease in humans, SARS-CoV, MERS-CoV and SARS-CoV-2 cause considerable mortality but also share significant sequence homology, and potentially antigenic epitopes capable of inducing an immune response. The degree of similarity is such that perhaps prior exposure to one virus could confer partial immunity to another. Indeed, data suggests a considerable amount of cross-reactivity and recognition by the hosts immune response between different coronavirus infections. While the ongoing COVID-19 outbreak rapidly overwhelmed medical facilities of particularly Europe and North America, accounting for 78% of global deaths, only 8% of deaths have occurred in Asia where the outbreak originated. Interestingly, Asia and the Middle East have previously experienced multiple rounds of coronavirus infections, perhaps suggesting buildup of acquired immunity to the causative SARS-CoV-2 that underlies COVID-19. This article hypothesizes that a causative factor underlying such low morbidity in these regions is perhaps (at least in part) due to acquired immunity from multiple rounds of coronavirus infections and discusses the mechanisms and recent evidence to support such assertions. Further investigations of such phenomenon would allow us to examine strategies to confer protective immunity, perhaps aiding vaccine development.
Collapse
|
9
|
Agrawal B, Gupta N, Vedi S, Singh S, Li W, Garg S, Li J, Kumar R. Heterologous Immunity between Adenoviruses and Hepatitis C Virus (HCV): Recombinant Adenovirus Vaccine Vectors Containing Antigens from Unrelated Pathogens Induce Cross-Reactive Immunity Against HCV Antigens. Cells 2019; 8:E507. [PMID: 31130710 PMCID: PMC6562520 DOI: 10.3390/cells8050507] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 05/13/2019] [Accepted: 05/24/2019] [Indexed: 12/15/2022] Open
Abstract
Host immune responses play an important role in the outcome of infection with hepatitis C virus (HCV). They can lead to viral clearance and a positive outcome, or progression and severity of chronic disease. Extensive research in the past >25 years into understanding the immune responses against HCV have still resulted in many unanswered questions implicating a role for unknown factors and events. In our earlier studies, we made a surprising discovery that peptides derived from structural and non-structural proteins of HCV have substantial amino acid sequence homologies with various proteins of adenoviruses and that immunizing mice with a non-replicating, non-recombinant adenovirus vector leads to induction of a robust cross-reactive cellular and humoral response against various HCV antigens. In this work, we further demonstrate antibody cross-reactivity between Ad and HCV in vivo. We also extend this observation to show that recombinant adenoviruses containing antigens from unrelated pathogens also possess the ability to induce cross-reactive immune responses against HCV antigens along with the induction of transgene antigen-specific immunity. This cross-reactive immunity can (a) accommodate the making of dual-pathogen vaccines, (b) play an important role in the natural course of HCV infection and (c) provide a plausible answer to many unexplained questions regarding immunity to HCV.
Collapse
Affiliation(s)
- Babita Agrawal
- Department of Surgery, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G2S2, Canada.
| | - Nancy Gupta
- Department of Laboratory Medicine & Pathology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G2S2, Canada.
| | - Satish Vedi
- Department of Laboratory Medicine & Pathology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G2S2, Canada.
| | - Shakti Singh
- Department of Surgery, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G2S2, Canada.
| | - Wen Li
- Department of Surgery, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G2S2, Canada.
| | - Saurabh Garg
- Department of Laboratory Medicine & Pathology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G2S2, Canada.
| | - Jie Li
- Department of Surgery, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G2S2, Canada.
| | - Rakesh Kumar
- Department of Laboratory Medicine & Pathology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G2S2, Canada.
| |
Collapse
|