1
|
Live Influenza Vaccine Provides Early Protection against Homologous and Heterologous Influenza and May Prevent Post-Influenza Pneumococcal Infections in Mice. Microorganisms 2022; 10:microorganisms10061150. [PMID: 35744668 PMCID: PMC9228789 DOI: 10.3390/microorganisms10061150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 05/27/2022] [Accepted: 05/30/2022] [Indexed: 02/04/2023] Open
Abstract
Influenza and S. pneumoniae infections are a significant cause of morbidity and mortality worldwide. Intranasal live influenza vaccine (LAIV) may prevent influenza-related bacterial complications. The objectives of the study are to estimate resistance against early influenza infection and post-influenza pneumococcal pneumonia after LAIV in mice. Mice were administered intranasally the monovalent LAIV A/17/Mallard Netherlands/00/95(H7N3), A/17/South Africa/2013/01(H1N1)pdm09 or trivalent LAIV 2017–2018 years of formulation containing A/17/New York/15/5364(H1N1)pdm09 vaccine strain. LAIV demonstrated early protection against homologous and heterologous infections with A/South Africa/3626/2013 (H1N1) pdm09 influenza virus on day six, following immunization. Following boost immunization, trivalent LAIV demonstrated a pronounced protective effect both in terms of lethality and pneumococcal lung infection when S. pneumoniae infection was performed three days after the onset of influenza infection. Conclusion: LAIV provides early protection against homologous and heterologous viral infections and has a protective effect against post-influenza pneumococcal infection. These data suggest that the intranasal administration of LAIV may be useful during the cycle of circulation not only of influenza viruses, but also of other causative agents of acute respiratory infections.
Collapse
|
2
|
Sender V, Hentrich K, Henriques-Normark B. Virus-Induced Changes of the Respiratory Tract Environment Promote Secondary Infections With Streptococcus pneumoniae. Front Cell Infect Microbiol 2021; 11:643326. [PMID: 33828999 PMCID: PMC8019817 DOI: 10.3389/fcimb.2021.643326] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 03/01/2021] [Indexed: 01/08/2023] Open
Abstract
Secondary bacterial infections enhance the disease burden of influenza infections substantially. Streptococcus pneumoniae (the pneumococcus) plays a major role in the synergism between bacterial and viral pathogens, which is based on complex interactions between the pathogen and the host immune response. Here, we discuss mechanisms that drive the pathogenesis of a secondary pneumococcal infection after an influenza infection with a focus on how pneumococci senses and adapts to the influenza-modified environment. We briefly summarize what is known regarding secondary bacterial infection in relation to COVID-19 and highlight the need to improve our current strategies to prevent and treat viral bacterial coinfections.
Collapse
Affiliation(s)
- Vicky Sender
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Karina Hentrich
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Birgitta Henriques-Normark
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden.,Clinical Microbiology, Karolinska University Hospital, Solna, Sweden
| |
Collapse
|
3
|
Sun Y, He Z, Li J, Gong S, Yuan S, Li T, Ning N, Xing L, Zhang L, Chen F, Li Z, Wang J, Luo D, Wang H. Gentamicin Induced Microbiome Adaptations Associate With Increased BCAA Levels and Enhance Severity of Influenza Infection. Front Immunol 2021; 11:608895. [PMID: 33708192 PMCID: PMC7940682 DOI: 10.3389/fimmu.2020.608895] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 12/22/2020] [Indexed: 12/12/2022] Open
Abstract
Involvement of gut microbiota in pulmonary disease by the gut-lung axis has been widely observed. However, the cross-talk messengers between respiratory mucosal immunity and gut microbiota are largely unknown. Using selective pharmacologic destruction of gut microenvironment mouse models, we found gut microbiota displayed significantly lower alpha diversity and relative abundance of bacteria in Gentamicin treated mice. Metagenomic studies revealed functional differences in gut bacteria in altering metabolic profiles in mice blood. Branched-chain amino acids (BCAAs) are the essential factors linked between gut and lung. During this process, selective destruction of gut microbiota by Gentamicin induced high levels of BCAAs, and the high levels of BCAAs impacted the lung immunity against influenza virus. In vivo, Gentamicin-treated mice or mice fed with high BCAAs diets displayed reduced survival. At the sites of infection, the number of CD11b+Ly6G+ cells decreased, and CD8+ T cells increased accompanied by exuberant expression of pro-inflammatory cytokines could result in tissue damage. CD11b+Ly6G+ cells transplantation conferred remarkable protection from influenza virus infections. In vitro, BCAAs promoted bone marrow-derived cells differentiation to dendritic cells. Taken together, these findings demonstrate that Gentamicin induced disruption of the gut microbiota leads to increased BCAA levels that suppress CD11b+Ly6c+ cell development in association with overactive CD8+ T responses which may contribute to enhanced severity of the viral infection.
Collapse
Affiliation(s)
- Yakun Sun
- Anhui Medical University, Hefei, China.,State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Zhili He
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Jiajia Li
- Anhui Medical University, Hefei, China.,State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Saisai Gong
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Shunzong Yuan
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Tao Li
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Nianzhi Ning
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Li Xing
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Liangyan Zhang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Fanghong Chen
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Zhan Li
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Jianxin Wang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Deyan Luo
- Anhui Medical University, Hefei, China.,State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Hui Wang
- Anhui Medical University, Hefei, China.,State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| |
Collapse
|
4
|
Zha H, Lu H, Wu J, Chang K, Wang Q, Zhang H, Li J, Luo Q, Lu Y, Li L. Vital Members in the More Dysbiotic Oropharyngeal Microbiotas in H7N9-Infected Patients. Front Med (Lausanne) 2020; 7:396. [PMID: 32850904 PMCID: PMC7433009 DOI: 10.3389/fmed.2020.00396] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Accepted: 06/24/2020] [Indexed: 01/09/2023] Open
Abstract
The dysbiosis of oropharyngeal (OP) microbiota is associated with multiple diseases, including H7N9 infection. Different OP microbial colonization states may reflect different severities or stages of disease and affect the effectiveness of the treatments. Current study aims to determine the vital bacteria that could possibly drive the OP microbiota in the H7N9 patients to more severe microbial dysbiosis state. The OP microbiotas of 42 H7N9 patients and 30 healthy subjects were analyzed by a series of bioinformatics and statistical analyses. Two clusters of OP microbiotas in H7N9 patients, i.e., Cluster_1_Diseased and Cluster_2_Diseased, were determined at two microbial colonization states by Partition Around Medoids (PAM) clustering analysis, each characterized by distinct operational taxonomic units (OTUs) and functional metabolites. Cluster_1_Diseased was determined at more severe dysbiosis status compared with Cluster_2_Diseased, while OTU143_Capnocytophaga and OTU269_Treponema acted as gatekeepers for both of the two clustered microbiotas. Nine OTUs assigned to seven taxa, i.e., Alloprevotella, Atopobium, Megasphaera, Oribacterium, Prevotella, Stomatobaculum, and Veillonella, were associated with both H7N9 patients with and without secondary bacterial lung infection in Cluster_1. In addition, two groups of healthy cohorts may have potential different susceptibilities to H7N9 infection. These findings suggest that two OP microbial colonization states of H7N9 patients were at different dysbiosis states, which may help determine the health status of H7N9 patients, as well as the susceptibility of healthy subjects to H7N9 infection.
Collapse
Affiliation(s)
- Hua Zha
- State Key Laboratory for Diagnosis and Treatment of Infectious Disease, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China.,School of Biological Sciences, The University of Auckland, Auckland, New Zealand.,Institute of Marine Science, The University of Auckland, Auckland, New Zealand
| | - Haifeng Lu
- State Key Laboratory for Diagnosis and Treatment of Infectious Disease, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Jieyun Wu
- School of Biological Sciences, The University of Auckland, Auckland, New Zealand.,Plant Health and Environment Laboratory, Ministry for Primary Industries, Auckland, New Zealand
| | - Kevin Chang
- Department of Statistics, The University of Auckland, Auckland, New Zealand
| | - Qiangqiang Wang
- State Key Laboratory for Diagnosis and Treatment of Infectious Disease, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Hua Zhang
- State Key Laboratory for Diagnosis and Treatment of Infectious Disease, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Jinyou Li
- Department of Geriatrics, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Qixia Luo
- State Key Laboratory for Diagnosis and Treatment of Infectious Disease, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Yanmeng Lu
- State Key Laboratory for Diagnosis and Treatment of Infectious Disease, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Lanjuan Li
- State Key Laboratory for Diagnosis and Treatment of Infectious Disease, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| |
Collapse
|
5
|
Shirani K, Sheikhbahaei E, Torkpour Z, Ghadiri Nejad M, Kamyab Moghadas B, Ghasemi M, Akbari Aghdam H, Ehsani A, Saber-Samandari S, Khandan A. A Narrative Review of COVID-19: The New Pandemic Disease. IRANIAN JOURNAL OF MEDICAL SCIENCES 2020; 45:233-249. [PMID: 32801413 PMCID: PMC7395956 DOI: 10.30476/ijms.2020.85869.1549] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Revised: 05/06/2020] [Accepted: 05/18/2020] [Indexed: 01/21/2023]
Abstract
Nearly every 100 years, humans collectively face a pandemic crisis. After the Spanish flu, now the world is in the grip of coronavirus disease 2019 (COVID-19). First detected in 2019 in the Chinese city of Wuhan, COVID-19 causes severe acute respiratory distress syndrome. Despite the initial evidence indicating a zoonotic origin, the contagion is now known to primarily spread from person to person through respiratory droplets. The precautionary measures recommended by the scientific community to halt the fast transmission of the disease failed to prevent this contagious disease from becoming a pandemic for a whole host of reasons. After an incubation period of about two days to two weeks, a spectrum of clinical manifestations can be seen in individuals afflicted by COVID-19: from an asymptomatic condition that can spread the virus in the environment, to a mild/moderate disease with cold/flu-like symptoms, to deteriorated conditions that need hospitalization and intensive care unit management, and then a fatal respiratory distress syndrome that becomes refractory to oxygenation. Several diagnostic modalities have been advocated and evaluated; however, in some cases, diagnosis is made on the clinical picture in order not to lose time. A consensus on what constitutes special treatment for COVID-19 has yet to emerge. Alongside conservative and supportive care, some potential drugs have been recommended and a considerable number of investigations are ongoing in this regard.
Collapse
Affiliation(s)
- Kiana Shirani
- Infectious Diseases and Tropical Medicine Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Erfan Sheikhbahaei
- Student Research Committee, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Zahra Torkpour
- Student Research Committee, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mazyar Ghadiri Nejad
- Industrial Engineering Department, Girne American University, Kyrenia, TRNC, Turkey
| | | | - Matina Ghasemi
- Faculty of Business and Economics, Business Department, Girne American University, Kyrenia, TRNC, Turkey
| | - Hossein Akbari Aghdam
- Department of Orthopedic Surgery, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Athena Ehsani
- Department of Biomedical Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | | | - Amirsalar Khandan
- Department of Electrical Engineering, Isfahan (Khorasgan) Branch, Islamic Azad University, Isfahan, Iran
- 0Technology Incubator Center, Isfahan (Khorasgan) Branch, Islamic Azad University, Isfahan, Iran
| |
Collapse
|
6
|
Keilich SR, Lorenzo EC, Torrance BL, Harrison AG, Bartley JM, Haynes L. Vaccination mitigates influenza-induced muscular declines in aged mice. GeroScience 2020; 42:1593-1608. [PMID: 32472355 DOI: 10.1007/s11357-020-00206-z] [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: 02/26/2020] [Accepted: 05/19/2020] [Indexed: 10/24/2022] Open
Abstract
Influenza (flu) infection increases the risk for disability, falls, and broken bones in older adults. We have employed a preclinical model to examine the impact of flu on muscle function, which has a direct impact on fall risk. In mice, flu causes mobility and strength impairments with induction of inflammatory and muscle degradation genes that are increased and prolonged with aging. To determine if vaccination could reduce flu-induced muscle decrements, mice were vaccinated with flu nucleoprotein, infected, and muscle parameters were measured. Vaccination of aged mice resulted in significant protection from functional decrements, muscle gene expressions alterations, and morphological damage. Vaccination also improved protection from lung localized and systemic inflammation in aged mice. Despite documented decreased vaccine efficacy with aging, vaccination still provided partial protection to aged mice and represents a potential strategy to prevent flu-induced disability. These findings provide translational insight on ways to reduce flu-induced disability with aging. Graphical abstract .
Collapse
Affiliation(s)
- Spencer R Keilich
- UConn Center on Aging, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT, 06030, USA.,Department of Immunology, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT, 06030, USA
| | - Erica C Lorenzo
- UConn Center on Aging, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT, 06030, USA.,Department of Immunology, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT, 06030, USA
| | - Blake L Torrance
- UConn Center on Aging, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT, 06030, USA.,Department of Immunology, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT, 06030, USA
| | - Andrew G Harrison
- Department of Immunology, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT, 06030, USA
| | - Jenna M Bartley
- UConn Center on Aging, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT, 06030, USA.,Department of Immunology, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT, 06030, USA
| | - Laura Haynes
- UConn Center on Aging, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT, 06030, USA. .,Department of Immunology, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT, 06030, USA.
| |
Collapse
|
7
|
Attenuation of Influenza A Virus Disease Severity by Viral Coinfection in a Mouse Model. J Virol 2018; 92:JVI.00881-18. [PMID: 30232180 DOI: 10.1128/jvi.00881-18] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 09/13/2018] [Indexed: 12/13/2022] Open
Abstract
Influenza viruses and rhinoviruses are responsible for a large number of acute respiratory viral infections in human populations and are detected as copathogens within hosts. Clinical and epidemiological studies suggest that coinfection by rhinovirus and influenza virus may reduce disease severity and that they may also interfere with each other's spread within a host population. To determine how coinfection by these two unrelated respiratory viruses affects pathogenesis, we established a mouse model using a minor serogroup rhinovirus (rhinovirus strain 1B [RV1B]) and mouse-adapted influenza A virus (A/Puerto Rico/8/1934 [PR8]). Infection of mice with RV1B 2 days before PR8 reduced the severity of infection by a low or medium, but not high, dose of PR8. Disease attenuation was associated with an early inflammatory response in the lungs and enhanced clearance of PR8. However, coinfection by RV1B did not reduce PR8 viral loads early in infection or inhibit replication of PR8 within respiratory epithelia or in vitro Inflammation in coinfected mice remained focal compared to diffuse inflammation and damage in the lungs of mice infected by PR8. The timing of RV1B coinfection was a critical determinant of protection, suggesting that sufficient time is needed to induce this response. Finally, disease attenuation was not unique to RV1B: dose-dependent coinfection by a murine coronavirus (mouse hepatitis virus strain 1 [MHV-1]) also reduced the severity of PR8 infection. Unlike RV1B, coinfection with MHV-1 reduced early PR8 replication, which was associated with upregulation of beta interferon (IFN-β) expression. This model is critical for understanding the mechanisms responsible for influenza disease attenuation during coinfection by unrelated respiratory viruses.IMPORTANCE Viral infections in the respiratory tract can cause severe disease and are responsible for a majority of pediatric hospitalizations. Molecular diagnostics have revealed that approximately 20% of these patients are infected by more than one unrelated viral pathogen. To understand how viral coinfection affects disease severity, we inoculated mice with a mild viral pathogen (rhinovirus or murine coronavirus), followed 2 days later by a virulent viral pathogen (influenza A virus). This model demonstrated that rhinovirus can reduce the severity of influenza A virus, which corresponded with an early but controlled inflammatory response in the lungs and early clearance of influenza A virus. We further determined the dose and timing parameters that were important for effective disease attenuation and showed that influenza disease is also reduced by coinfection with a murine coronavirus. These findings demonstrate that coinfecting viruses can alter immune responses and pathogenesis in the respiratory tract.
Collapse
|
8
|
Li X, Li C, Liu JC, Pan YP, Li YG. In vitro effect of Porphyromonas gingivalis combined with influenza A virus on respiratory epithelial cells. Arch Oral Biol 2018; 95:125-133. [PMID: 30107300 DOI: 10.1016/j.archoralbio.2018.04.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 03/08/2018] [Accepted: 04/04/2018] [Indexed: 12/14/2022]
Abstract
OBJECTIVE Respiratory epithelial cells are the first natural barrier against bacteria and viruses; hence, the interactions among epithelial cells, bacteria, and viruses are associated with disease occurrence and development. The effect of co-infection by P. gingivalis and influenza A virus (IAV) on respiratory epithelial cells remains unknown. The aim of this study was to analyze in vitro cell viability and apoptosis rates in respiratory epithelial A549 cells infected with P. gingivalis or IAV alone, or a combination of both pathogens. DESIGN A549 cells were first divided into a control group, a P. gingivalis group, an IAV group, and a P. gingivalis + IAV group, to examine cell viability and apoptosis rates, the levels of microtubule associated protein 1 light chain 3 B (LC3-II), microtubule associated protein 1 light chain 3A (LC3-I), and sequestosome 1 (P62), and the formation of autophagosomes. The autophagy inhibitor, 3-methyladenine (3MA), was used to assess autophagy and apoptosis in A549 cells infected with P. gingivalis or IAV. RESULTS An MTT assay revealed that cell viability was significantly lower in the IAV group than in the P. gingivalis + IAV group (P < 0.05). Flow cytometry indicated that the apoptosis rate was significantly higher in the IAV group than in the P. gingivalis + IAV group (P < 0.05). The fluorescence levels of GFP-LC3 increased significantly, the LC3-II/LC3-I ratio was significantly higher, and the P62 protein levels were statistically lower in the P. gingivalis + IAV group compared with the IAV group (all P < 0.05). Western blotting revealed that the LC3- II/LC3-I ratio was significantly lower, and caspase-3 levels were significantly higher in the 3MA + P. gingivalis + IAV group compared to the P. gingivalis + IAV group (all P < 0.05). CONCLUSION In vitro studies showed that infection by P. gingivalis combined with IAV temporarily inhibited apoptosis in respiratory epithelial cells, and this may be related to the initiation of autophagy.
Collapse
Affiliation(s)
- Xin Li
- Department of Periodontics and Oral Biology, School of Stomatology, China Medical University, Nanjing North St. 117, Shenyang 110002, Liaoning Province, China.
| | - Chen Li
- Department of Periodontics and Oral Biology, School of Stomatology, China Medical University, Nanjing North St. 117, Shenyang 110002, Liaoning Province, China.
| | - Jun-Chao Liu
- Department of Periodontics and Oral Biology, School of Stomatology, China Medical University, Nanjing North St. 117, Shenyang 110002, Liaoning Province, China.
| | - Ya-Ping Pan
- Department of Periodontics and Oral Biology, School of Stomatology, China Medical University, Nanjing North St. 117, Shenyang 110002, Liaoning Province, China.
| | - Yong-Gang Li
- Department of Immunology and Microbiology, Jinzhou Medical University, Jinzhou 121000, Liaoning Province, China.
| |
Collapse
|
9
|
The impact of aging on CD4 + T cell responses to influenza infection. Biogerontology 2018; 19:437-446. [PMID: 29616390 PMCID: PMC6170716 DOI: 10.1007/s10522-018-9754-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 03/23/2018] [Indexed: 12/29/2022]
Abstract
CD4+ T cells are important for generating high quality and robust immune responses to influenza infection. Immunosenescence that occurs with aging, however, compromises the ability of CD4+ T cells to differentiate into functional subsets resulting in a multitude of dysregulated responses namely, delayed viral clearance and prolonged inflammation leading to increased pathology. Current research employing animal models and human subjects has provided new insights into the description and mechanisms of age-related CD4+ T cell changes. In this review, we will discuss the consequences of aging on CD4+ T cell differentiation and function and how this influences the initial CD4+ T cell effector responses to influenza infection. Understanding these age-related alterations will aid in the pharmacological development of therapeutic treatments and improved vaccination strategies for the vulnerable elderly population.
Collapse
|
10
|
Disordered oropharyngeal microbial communities in H7N9 patients with or without secondary bacterial lung infection. Emerg Microbes Infect 2017; 6:e112. [PMID: 29259328 PMCID: PMC5750457 DOI: 10.1038/emi.2017.101] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Revised: 11/02/2017] [Accepted: 11/07/2017] [Indexed: 02/06/2023]
Abstract
Secondary bacterial lung infection (SBLI) is a serious complication in patients with H7N9 virus infection, and increases disease severity. The oropharyngeal (OP) microbiome helps prevent colonisation of respiratory pathogens. We aimed to investigate the OP microbiome of H7N9 patients with/without secondary bacterial pneumonia using 16S rRNA gene sequencing. OP swab samples were collected from 51 H7N9 patients (21 with SBLI and 30 without) and 30 matched healthy controls (HCs) and used for comparative composition, diversity and richness analyses of microbial communities. Principal coordinates analysis successfully distinguished between the OP microbiomes of H7N9 patients and healthy subjects, and the OP microbiome diversity of patients with SBLI was significantly increased. There was significant dysbiosis of the OP microbiome in H7N9 patients, with an abundance of Leptotrichia, Oribacterium, Streptococcus, Atopobium, Eubacterium, Solobacterium and Rothia species in patients with SBLI, and Filifactor, Megasphaera and Leptotrichia species in patients without SBLI, when compared with HCs. Importantly, Haemophilus and Bacteroides species were enriched in HCs. These findings revealed dysbiosis of the OP microbiota in H7N9 patients, and identified OP microbial risk indicators of SBLI, suggesting that the OP microbiome could provide novel and non-invasive diagnostic biomarkers for early microbiota-targeted prophylactic therapies for SBLI prevention.
Collapse
|
11
|
Pettigrew MM, Alderson MR, Bakaletz LO, Barenkamp SJ, Hakansson AP, Mason KM, Nokso-Koivisto J, Patel J, Pelton SI, Murphy TF. Panel 6: Vaccines. Otolaryngol Head Neck Surg 2017; 156:S76-S87. [PMID: 28372533 DOI: 10.1177/0194599816632178] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Objective To review the literature on progress regarding (1) effectiveness of vaccines for prevention of otitis media (OM) and (2) development of vaccine antigens for OM bacterial and viral pathogens. Data Sources PubMed database of the National Library of Science. Review Methods We performed literature searches in PubMed for OM pathogens and candidate vaccine antigens, and we restricted the searches to articles in English that were published between July 2011 and June 2015. Panel members reviewed literature in their area of expertise. Conclusions Pneumococcal conjugate vaccines (PCVs) are somewhat effective for the prevention of pneumococcal OM, recurrent OM, OM visits, and tympanostomy tube insertions. Widespread use of PCVs has been associated with shifts in pneumococcal serotypes and bacterial pathogens associated with OM, diminishing PCV effectiveness against AOM. The 10-valent pneumococcal vaccine containing Haemophilus influenzae protein D (PHiD-CV) is effective for pneumococcal OM, but results from studies describing the potential impact on OM due to H influenzae have been inconsistent. Progress in vaccine development for H influenzae, Moraxella catarrhalis, and OM-associated respiratory viruses has been limited. Additional research is needed to extend vaccine protection to additional pneumococcal serotypes and other otopathogens. There are likely to be licensure challenges for protein-based vaccines, and data on correlates of protection for OM vaccine antigens are urgently needed. Implications for Practice OM continues to be a significant health care burden globally. Prevention is preferable to treatment, and vaccine development remains an important goal. As a polymicrobial disease, OM poses significant but not insurmountable challenges for vaccine development.
Collapse
Affiliation(s)
- Melinda M Pettigrew
- 1 Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven Connecticut, USA
| | | | - Lauren O Bakaletz
- 3 Center for Microbial Pathogenesis, The Research Institute at Nationwide Children's Hospital, and Department of Pediatrics, The Ohio State University College of Medicine, Columbus, Ohio, USA
| | | | | | - Kevin M Mason
- 3 Center for Microbial Pathogenesis, The Research Institute at Nationwide Children's Hospital, and Department of Pediatrics, The Ohio State University College of Medicine, Columbus, Ohio, USA
| | | | - Janak Patel
- 7 University of Texas Medical Branch, Galveston, Texas, USA
| | - Stephen I Pelton
- 8 Boston University School of Medicine, Boston, Massachusetts, USA
| | - Timothy F Murphy
- 9 University at Buffalo, The State University of New York, Buffalo, New York, USA
| |
Collapse
|
12
|
Desheva YA, Leontieva GF, Kramskaya TA, Smolonogina TA, Grabovskaya KB, Kiseleva IV, Rudenko LG, Suvorov AN. Evaluation in Mouse Model of Combined Virus-bacterial Vaccine Based on Attenuated Influenza A(H7N3) Virus and the Group B Streptococcus Recombinant Polypeptides. Open Microbiol J 2016; 10:168-175. [PMID: 27867430 PMCID: PMC5101632 DOI: 10.2174/1874285801610010168] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Revised: 10/06/2016] [Accepted: 10/06/2016] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Secondary bacterial influenza complications are a common cause of excesses morbidity and mortality, which determines the need to develop means for specific prophylaxis. Group B streptococcal infection is especially common cause of pneumonia among children and the elderly with underlying conditions. Here we investigate in a mouse model the effects of combined intranasal immunization using live attenuated influenza vaccine and recombinant polypeptides based on group B Streptococcus surface proteins. METHODS Groups of outbred mice received two doses of the following preparations: 1) the reassortant A/17/Mallard/Netherlands/00/95 (H7N3) influenza virus; 2) a mixture of P6, ScaAB, ScpB1 and Stv recombinant GBS proteins (20 µg total); 3) the A(H7N3) influenza vaccine pooled with the four bacterial peptide preparation; 4) control animals were treated with PBS. RESULTS Intranasal vaccination using LAIV in combination with GBS polypeptides provided advantageous protection against infections with homologous A/Mallard/Netherlands/12/00 (H7N3) wild type virus or heterologous A/Puerto Rico/8/34 (H1N1) followed by serotype II GBS infection. Also, combined vaccination improved bacterial clearance from the lungs of mice. CONCLUSION Intranasal immunization with LAIV+GBSV was safe and enabled to induce the antibody response to each of vaccine components. Thus, the combined vaccine increased the protective effect against influenza and its bacterial complications in mice compared to LAIV-only.
Collapse
Affiliation(s)
- Yulia A Desheva
- Federal State Budgetary Scientific Institution "Institute of Experimental Medicine", Saint Petersburg, Russian Federation; Saint Petersburg State University, Saint Petersburg, Russian Federation
| | - Galina F Leontieva
- Federal State Budgetary Scientific Institution "Institute of Experimental Medicine", Saint Petersburg, Russian Federation
| | - Tatiana A Kramskaya
- Federal State Budgetary Scientific Institution "Institute of Experimental Medicine", Saint Petersburg, Russian Federation
| | - Tatiana A Smolonogina
- Federal State Budgetary Scientific Institution "Institute of Experimental Medicine", Saint Petersburg, Russian Federation
| | - Kornelia B Grabovskaya
- Federal State Budgetary Scientific Institution "Institute of Experimental Medicine", Saint Petersburg, Russian Federation
| | - Irina V Kiseleva
- Federal State Budgetary Scientific Institution "Institute of Experimental Medicine", Saint Petersburg, Russian Federation; Saint Petersburg State University, Saint Petersburg, Russian Federation
| | - Larisa G Rudenko
- Federal State Budgetary Scientific Institution "Institute of Experimental Medicine", Saint Petersburg, Russian Federation
| | - Alexander N Suvorov
- Federal State Budgetary Scientific Institution "Institute of Experimental Medicine", Saint Petersburg, Russian Federation; Saint Petersburg State University, Saint Petersburg, Russian Federation
| |
Collapse
|
13
|
Host Physiologic Changes Induced by Influenza A Virus Lead to Staphylococcus aureus Biofilm Dispersion and Transition from Asymptomatic Colonization to Invasive Disease. mBio 2016; 7:mBio.01235-16. [PMID: 27507829 PMCID: PMC4981728 DOI: 10.1128/mbio.01235-16] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Staphylococcus aureus is a ubiquitous opportunistic human pathogen and a major health concern worldwide, causing a wide variety of diseases from mild skin infections to systemic disease. S. aureus is a major source of severe secondary bacterial pneumonia after influenza A virus infection, which causes widespread morbidity and mortality. While the phenomenon of secondary bacterial pneumonia is well established, the mechanisms behind the transition from asymptomatic colonization to invasive staphylococcal disease following viral infection remains unknown. In this report, we have shown that S. aureus biofilms, grown on an upper respiratory epithelial substratum, disperse in response to host physiologic changes related to viral infection, such as febrile range temperatures, exogenous ATP, norepinephrine, and increased glucose. Mice that were colonized with S. aureus and subsequently exposed to these physiologic stimuli or influenza A virus coinfection developed pronounced pneumonia. This study provides novel insight into the transition from colonization to invasive disease, providing a better understanding of the events involved in the pathogenesis of secondary staphylococcal pneumonia. In this study, we have determined that host physiologic changes related to influenza A virus infection causes S. aureus to disperse from a biofilm state. Additionally, we report that these same host physiologic changes promote S. aureus dissemination from the nasal tissue to the lungs in an animal model. Furthermore, this study identifies important aspects involved in the transition of S. aureus from asymptomatic colonization to pneumonia.
Collapse
|
14
|
Lefebvre JS, Lorenzo EC, Masters AR, Hopkins JW, Eaton SM, Smiley ST, Haynes L. Vaccine efficacy and T helper cell differentiation change with aging. Oncotarget 2016; 7:33581-94. [PMID: 27177221 PMCID: PMC5085104 DOI: 10.18632/oncotarget.9254] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Accepted: 04/27/2016] [Indexed: 12/22/2022] Open
Abstract
Influenza and pneumonia are leading causes of death in elderly populations. With age, there is an increased inflammatory response and slower viral clearance during influenza infection which increases the risk of extended illness and mortality. Here we employ a preclinical murine model of influenza infection to examine the protective capacity of vaccination with influenza nucleoprotein (NP). While NP vaccination reduces influenza-induced lung inflammation in young mice, aged mice do not show this reduction, but are protected from influenza-induced mortality. Aged mice do make a significant amount of NP-specific IgG and adoptive transfer experiments show that NP antibody can protect from death but cannot reduce lung inflammation. Furthermore, young but not aged vaccinated mice generate significant numbers of NP-specific T cells following subsequent infection and few of these T cells are found in aged lungs early during infection. Importantly, aged CD4 T cells have a propensity to differentiate towards a T follicular helper (Tfh) phenotype rather than a T helper 1 (Th1) phenotype that predominates in the young. Since Th1 cells are important in viral clearance, reduced Th1 differentiation in the aged is critical and could account for some or all of the age-related differences in vaccine responses and infection resolution.
Collapse
Affiliation(s)
- Julie S. Lefebvre
- The Trudeau Institute, Saranac Lake, NY, United States of America
- Département de Pneumologie, Centre de Recherche de l'Institut Universitaire de Cardiologie et Pneumologie de Québec, Québec, QC, Canada
| | - Erica C. Lorenzo
- Department of Immunology and Center on Aging, University of Connecticut Health Center, Farmington, CT, United States of America
| | - April R. Masters
- Department of Immunology and Center on Aging, University of Connecticut Health Center, Farmington, CT, United States of America
| | - Jacob W. Hopkins
- Department of Immunology and Center on Aging, University of Connecticut Health Center, Farmington, CT, United States of America
| | - Sheri M. Eaton
- The Trudeau Institute, Saranac Lake, NY, United States of America
| | - Stephen T. Smiley
- The Trudeau Institute, Saranac Lake, NY, United States of America
- NIAID/NIH, Bethesda, MD, USA
| | - Laura Haynes
- Department of Immunology and Center on Aging, University of Connecticut Health Center, Farmington, CT, United States of America
| |
Collapse
|
15
|
Lee B, Robinson KM, McHugh KJ, Scheller EV, Mandalapu S, Chen C, Di YP, Clay ME, Enelow RI, Dubin PJ, Alcorn JF. Influenza-induced type I interferon enhances susceptibility to gram-negative and gram-positive bacterial pneumonia in mice. Am J Physiol Lung Cell Mol Physiol 2015; 309:L158-67. [PMID: 26001778 DOI: 10.1152/ajplung.00338.2014] [Citation(s) in RCA: 100] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 05/16/2015] [Indexed: 11/22/2022] Open
Abstract
Suppression of type 17 immunity by type I interferon (IFN) during influenza A infection has been shown to enhance susceptibility to secondary bacterial pneumonia. Although this mechanism has been described in coinfection with gram-positive bacteria, it is unclear whether similar mechanisms may impair lung defense against gram-negative infections. Furthermore, precise delineation of the duration of type I IFN-associated susceptibility to bacterial infection remains underexplored. Therefore, we investigated the effects of preceding influenza A virus infection on subsequent challenge with the gram-negative bacteria Escherichia coli or Pseudomonas aeruginosa and the temporal association between IFN expression with susceptibility to Staphylococcus aureus challenge in a mouse model of influenza and bacterial coinfection. Here we demonstrate that preceding influenza A virus led to increased lung E. coli and P. aeruginosa bacterial burden, which was associated with suppression of type 17 immunity and attenuation of antimicrobial peptide expression. Enhanced susceptibility to S. aureus coinfection ceased at day 14 of influenza infection, when influenza-associated type I IFN levels had returned to baseline levels, further suggesting a key role for type I IFN in coinfection pathogenesis. These findings further implicate type I IFN-associated suppression of type 17 immunity and antimicrobial peptide production as a conserved mechanism for enhanced susceptibility to both gram-positive and gram-negative bacterial coinfection during influenza infection.
Collapse
Affiliation(s)
- Benjamin Lee
- Department of Pediatrics, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, Pennsylvania
| | - Keven M Robinson
- Department of Pediatrics, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, Pennsylvania; Department of Medicine, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania
| | - Kevin J McHugh
- Department of Pediatrics, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, Pennsylvania
| | - Erich V Scheller
- Department of Pediatrics, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, Pennsylvania
| | - Sivanarayana Mandalapu
- Department of Pediatrics, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, Pennsylvania
| | - Chen Chen
- Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, Pennsylvania; and
| | - Y Peter Di
- Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, Pennsylvania; and
| | - Michelle E Clay
- Department of Pediatrics, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, Pennsylvania
| | - Richard I Enelow
- Department of Medicine, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire
| | - Patricia J Dubin
- Department of Pediatrics, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, Pennsylvania
| | - John F Alcorn
- Department of Pediatrics, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, Pennsylvania;
| |
Collapse
|
16
|
Metzger DW, Furuya Y, Salmon SL, Roberts S, Sun K. Limited Efficacy of Antibacterial Vaccination Against Secondary Serotype 3 Pneumococcal Pneumonia Following Influenza Infection. J Infect Dis 2015; 212:445-52. [PMID: 25649173 DOI: 10.1093/infdis/jiv066] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 01/26/2015] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND Secondary bacterial infections following influenza represent a major cause of mortality in the human population, which, in turn, has led to a call for stockpiling of bacterial vaccines for pandemic preparedness. METHODS To investigate the efficacy of bacterial vaccination for protection against secondary pneumococcal infection, mice were immunized with pneumococcal capsular polysaccharide conjugate vaccine, and then sequentially coinfected 5 weeks later with PR8 influenza virus and A66.1 Streptococcus pneumoniae. RESULTS In the absence of influenza virus exposure, vaccination with polysaccharide conjugate vaccine was highly effective, as indicated by 100% survival from lethal pneumococcal pneumonia and 10 000-fold greater efficiency in clearance of bacteria from the lung compared to unvaccinated mice. Enhanced clearance after vaccination was dependent upon Fc receptor (FcR) expression. However, following influenza, <40% of vaccinated mice survived bacterial coinfection and FcR-dependent clearance of antibody-opsonized bacteria reduced bacterial levels in the lungs only 5-10 fold. No differences in lung myeloid cell numbers or in FcR cell surface expression were observed following influenza. CONCLUSIONS The results show that induction of antibacterial humoral immunity is only partially effective in protection against secondary bacterial infections that occur following influenza, and suggest that additional therapeutic strategies to overcome defective antibacterial immunity should be explored.
Collapse
Affiliation(s)
- Dennis W Metzger
- Center for Immunology and Microbial Disease, Albany Medical College, New York
| | - Yoichi Furuya
- Center for Immunology and Microbial Disease, Albany Medical College, New York
| | - Sharon L Salmon
- Center for Immunology and Microbial Disease, Albany Medical College, New York
| | - Sean Roberts
- Center for Immunology and Microbial Disease, Albany Medical College, New York
| | - Keer Sun
- Center for Immunology and Microbial Disease, Albany Medical College, New York
| |
Collapse
|
17
|
Lethal coinfection of influenza virus and Streptococcus pneumoniae lowers antibody response to influenza virus in lung and reduces numbers of germinal center B cells, T follicular helper cells, and plasma cells in mediastinal lymph Node. J Virol 2014; 89:2013-23. [PMID: 25428873 DOI: 10.1128/jvi.02455-14] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Secondary Streptococcus pneumoniae infection after influenza is a significant clinical complication resulting in morbidity and sometimes mortality. Prior influenza virus infection has been demonstrated to impair the macrophage and neutrophil response to the subsequent pneumococcal infection. In contrast, how a secondary pneumococcal infection after influenza can affect the adaptive immune response to the initial influenza virus infection is less well understood. Therefore, this study focuses on how secondary pneumococcal infection after influenza may impact the humoral immune response to the initial influenza virus infection in a lethal coinfection mouse model. Compared to mice infected with influenza virus alone, mice coinfected with influenza virus followed by pneumococcus had significant body weight loss and 100% mortality. In the lung, lethal coinfection significantly increased virus titers and bacterial cell counts and decreased the level of virus-specific IgG, IgM, and IgA, as well as the number of B cells, CD4 T cells, and plasma cells. Lethal coinfection significantly reduced the size and weight of spleen, as well as the number of B cells along the follicular developmental lineage. In mediastinal lymph nodes, lethal coinfection significantly decreased germinal center B cells, T follicular helper cells, and plasma cells. Adoptive transfer of influenza virus-specific immune serum to coinfected mice improved survival, suggesting the protective functions of anti-influenza virus antibodies. In conclusion, coinfection reduced the B cell response to influenza virus. This study helps us to understand the modulation of the B cell response to influenza virus during a lethal coinfection. IMPORTANCE Secondary pneumococcal infection after influenza virus infection is an important clinical issue that often results in excess mortality. Since antibodies are key mediators of protection, this study aims to examine the antibody response to influenza virus and demonstrates that lethal coinfection reduced the B cell response to influenza virus. This study helps to highlight the complexity of the modulation of the B cell response in the context of coinfection.
Collapse
|
18
|
Pasquali C, Salami O, Taneja M, Gollwitzer ES, Trompette A, Pattaroni C, Yadava K, Bauer J, Marsland BJ. Enhanced Mucosal Antibody Production and Protection against Respiratory Infections Following an Orally Administered Bacterial Extract. Front Med (Lausanne) 2014; 1:41. [PMID: 25593914 PMCID: PMC4292070 DOI: 10.3389/fmed.2014.00041] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Accepted: 10/12/2014] [Indexed: 01/19/2023] Open
Abstract
Secondary bacterial infections following influenza infection are a pressing problem facing respiratory medicine. Although antibiotic treatment has been highly successful over recent decades, fatalities due to secondary bacterial infections remain one of the leading causes of death associated with influenza. We have assessed whether administration of a bacterial extract alone is sufficient to potentiate immune responses and protect against primary infection with influenza, and secondary infections with either Streptococcus pneumoniae or Klebsiella pneumoniae in mice. We show that oral administration with the bacterial extract, OM-85, leads to a maturation of dendritic cells and B-cells characterized by increases in MHC II, CD86, and CD40, and a reduction in ICOSL. Improved immune responsiveness against influenza virus reduced the threshold of susceptibility to secondary bacterial infections, and thus protected the mice. The protection was associated with enhanced polyclonal B-cell activation and release of antibodies that were effective at neutralizing the virus. Taken together, these data show that oral administration of bacterial extracts provides sufficient mucosal immune stimulation to protect mice against a respiratory tract viral infection and associated sequelae.
Collapse
Affiliation(s)
| | - Olawale Salami
- Faculty of Biology and Medicine, University of Lausanne, Service de Pneumologie, CHUV , Lausanne , Switzerland
| | - Manisha Taneja
- Faculty of Biology and Medicine, University of Lausanne, Service de Pneumologie, CHUV , Lausanne , Switzerland
| | - Eva S Gollwitzer
- Faculty of Biology and Medicine, University of Lausanne, Service de Pneumologie, CHUV , Lausanne , Switzerland
| | - Aurelien Trompette
- Faculty of Biology and Medicine, University of Lausanne, Service de Pneumologie, CHUV , Lausanne , Switzerland
| | - Céline Pattaroni
- Faculty of Biology and Medicine, University of Lausanne, Service de Pneumologie, CHUV , Lausanne , Switzerland
| | - Koshika Yadava
- Faculty of Biology and Medicine, University of Lausanne, Service de Pneumologie, CHUV , Lausanne , Switzerland
| | | | - Benjamin J Marsland
- Faculty of Biology and Medicine, University of Lausanne, Service de Pneumologie, CHUV , Lausanne , Switzerland
| |
Collapse
|
19
|
Wang W, Huang B, Jiang T, Wang X, Qi X, Tan W, Ruan L. Maximal immune response and cross protection by influenza virus nucleoprotein derived from E. coli using an optimized formulation. Virology 2014; 468-470:265-273. [PMID: 25213406 DOI: 10.1016/j.virol.2014.08.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 07/11/2014] [Accepted: 08/09/2014] [Indexed: 12/16/2022]
Abstract
The highly conserved internal nucleoprotein (NP) is a promising antigen to develop a universal influenza A virus vaccine. In this study, mice were injected intramuscularly with Escherichia coli-derived NP protein alone or in combination with adjuvant alum (Al(OH)3), CpG or both. The results showed that the NP protein formulated with adjuvant was effective in inducing a protective immune response. Additionally, the adjuvant efficacy of Al(OH)3 was stronger than that of CpG. Optimal immune responses were observed in BALB/c mice immunized with a combination of NP protein plus Al(OH)3 and CpG. These mice also showed maximal resistance following challenge with influenza A virus PR8 strain. Most importantly, 10 µg NP formulated with Al(OH)3 and CpG induced higher protection than did 90 µg NP. These findings indicated that a combination of Al(OH)3 and CpG may be an efficient adjuvant in the NP formulation.
Collapse
Affiliation(s)
- Wenling Wang
- National Institute for Viral Disease Control & Prevention, Chinese Center for Disease Control and Prevention (China CDC), 155# Chang Bai Road, Chang Ping District, Beijing 102206, China
| | - Baoying Huang
- National Institute for Viral Disease Control & Prevention, Chinese Center for Disease Control and Prevention (China CDC), 155# Chang Bai Road, Chang Ping District, Beijing 102206, China
| | - Tao Jiang
- National Institute for Viral Disease Control & Prevention, Chinese Center for Disease Control and Prevention (China CDC), 155# Chang Bai Road, Chang Ping District, Beijing 102206, China
| | - Xiuping Wang
- National Institute for Viral Disease Control & Prevention, Chinese Center for Disease Control and Prevention (China CDC), 155# Chang Bai Road, Chang Ping District, Beijing 102206, China
| | - Xiangrong Qi
- National Institute for Viral Disease Control & Prevention, Chinese Center for Disease Control and Prevention (China CDC), 155# Chang Bai Road, Chang Ping District, Beijing 102206, China
| | - Wenjie Tan
- National Institute for Viral Disease Control & Prevention, Chinese Center for Disease Control and Prevention (China CDC), 155# Chang Bai Road, Chang Ping District, Beijing 102206, China
| | - Li Ruan
- National Institute for Viral Disease Control & Prevention, Chinese Center for Disease Control and Prevention (China CDC), 155# Chang Bai Road, Chang Ping District, Beijing 102206, China.
| |
Collapse
|
20
|
Nonneutralizing functional antibodies: a new "old" paradigm for HIV vaccines. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2014; 21:1023-36. [PMID: 24920599 DOI: 10.1128/cvi.00230-14] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Animal and human data from various viral infections and vaccine studies suggest that nonneutralizing antibodies (nNAb) without neutralizing activity in vitro may play an important role in protection against viral infection in vivo. This was illustrated by the recent human immunodeficiency virus (HIV) RV144 vaccine efficacy trial, which demonstrated that HIV-specific IgG-mediated nNAb directed against the V2 loop of HIV type 1 envelope (Env) were inversely correlated with risk for HIV acquisition, while Env-specific plasma IgA-mediated antibodies were directly correlated with risk. However, tier 1 NAb in the subset of responders with a low level of plasma Env-specific IgA correlated with decreased risk. Nonhuman primate simian immunodeficiency virus (SIV) and simian-human immunodeficiency virus (SHIV) challenge studies suggest that Env-mediated antibodies are essential and sufficient for protection. A comparison of immune responses generated in human efficacy trials reveals subtle differences in the fine specificities of the antibody responses, in particular in HIV-specific IgG subclasses. The underlying mechanisms that may have contributed to protection against HIV acquisition in humans, although not fully understood, are possibly mediated by antibody-dependent cell-mediated cytotoxicity (ADCC) and/or other nonneutralizing humoral effector functions, such as antibody-mediated phagocytosis. The presence of such functional nNAb in mucosal tissues and cervico-vaginal and rectal secretions challenges the paradigm that NAb are the predominant immune response conferring protection, although this does not negate the desirability of evoking neutralizing antibodies through vaccination. Instead, NAb and nNAb should be looked upon as complementary or synergistic humoral effector functions. Several HIV vaccine clinical trials to study these antibody responses in various prime-boost modalities in the systemic and mucosal compartments are ongoing. The induction of high-frequency HIV-specific functional nNAb at high titers may represent an attractive hypothesis-testing strategy in future HIV vaccine efficacy trials.
Collapse
|
21
|
Worobey M, Han GZ, Rambaut A. Genesis and pathogenesis of the 1918 pandemic H1N1 influenza A virus. Proc Natl Acad Sci U S A 2014; 111:8107-12. [PMID: 24778238 PMCID: PMC4050607 DOI: 10.1073/pnas.1324197111] [Citation(s) in RCA: 152] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The source, timing, and geographical origin of the 1918-1920 pandemic influenza A virus have remained tenaciously obscure for nearly a century, as have the reasons for its unusual severity among young adults. Here, we reconstruct the origins of the pandemic virus and the classic swine influenza and (postpandemic) seasonal H1N1 lineages using a host-specific molecular clock approach that is demonstrably more accurate than previous methods. Our results suggest that the 1918 pandemic virus originated shortly before 1918 when a human H1 virus, which we infer emerged before ∼1907, acquired avian N1 neuraminidase and internal protein genes. We find that the resulting pandemic virus jumped directly to swine but was likely displaced in humans by ∼1922 by a reassortant with an antigenically distinct H1 HA. Hence, although the swine lineage was a direct descendent of the pandemic virus, the post-1918 seasonal H1N1 lineage evidently was not, at least for HA. These findings help resolve several seemingly disparate observations from 20th century influenza epidemiology, seroarcheology, and immunology. The phylogenetic results, combined with these other lines of evidence, suggest that the high mortality in 1918 among adults aged ∼20 to ∼40 y may have been due primarily to their childhood exposure to a doubly heterosubtypic putative H3N8 virus, which we estimate circulated from ∼1889-1900. All other age groups (except immunologically naive infants) were likely partially protected by childhood exposure to N1 and/or H1-related antigens. Similar processes may underlie age-specific mortality differences between seasonal H1N1 vs. H3N2 and human H5N1 vs. H7N9 infections.
Collapse
MESH Headings
- Adult
- Aged
- Animals
- Biological Evolution
- Birds
- Child
- Disease Resistance/immunology
- Genetic Variation
- Humans
- Influenza A Virus, H1N1 Subtype/genetics
- Influenza A Virus, H1N1 Subtype/immunology
- Influenza A Virus, H1N1 Subtype/pathogenicity
- Influenza A Virus, H3N2 Subtype/genetics
- Influenza A Virus, H3N2 Subtype/immunology
- Influenza A Virus, H3N2 Subtype/pathogenicity
- Influenza A Virus, H3N8 Subtype/genetics
- Influenza A Virus, H3N8 Subtype/immunology
- Influenza A Virus, H3N8 Subtype/pathogenicity
- Influenza A Virus, H5N1 Subtype/genetics
- Influenza A Virus, H5N1 Subtype/immunology
- Influenza A Virus, H5N1 Subtype/pathogenicity
- Influenza A Virus, H7N9 Subtype/genetics
- Influenza A Virus, H7N9 Subtype/immunology
- Influenza A Virus, H7N9 Subtype/pathogenicity
- Influenza A virus/genetics
- Influenza A virus/immunology
- Influenza A virus/pathogenicity
- Influenza Pandemic, 1918-1919/mortality
- Influenza, Human/mortality
- Influenza, Human/virology
- Phylogeny
- Reassortant Viruses/genetics
- Reassortant Viruses/immunology
- Reassortant Viruses/pathogenicity
- Swine
- Virulence
Collapse
Affiliation(s)
- Michael Worobey
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721;
| | - Guan-Zhu Han
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721
| | - Andrew Rambaut
- Institute of Evolutionary Biology andCentre for Infection, Immunity, and Evolution, University of Edinburgh, Edinburgh EH9 3JT, United Kingdom; andFogarty International Center, National Institutes of Health, Bethesda, MD 20892
| |
Collapse
|
22
|
Dangor Z, Izu A, Moore DP, Nunes MC, Solomon F, Beylis N, von Gottberg A, McAnerney JM, Madhi SA. Temporal association in hospitalizations for tuberculosis, invasive pneumococcal disease and influenza virus illness in South African children. PLoS One 2014; 9:e91464. [PMID: 24618667 PMCID: PMC3950213 DOI: 10.1371/journal.pone.0091464] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Accepted: 02/11/2014] [Indexed: 11/18/2022] Open
Abstract
Introduction The seasonal variability in hospitalization for tuberculosis may in part relate to super-imposed bacterial or predisposing respiratory viral infections. We aimed to study the temporal association between hospitalization for culture-confirmed pulmonary tuberculosis (PTB), invasive pneumococcal disease (IPD) and influenza virus epidemics in South African children. Methods We undertook a retrospective analysis which examined seasonal trends, from 2005 to 2008, for hospitalization for culture-confirmed PTB and IPD among children in relation to the influenza epidemics in Soweto, South Africa. Original time-series of the influenza virus epidemics and hospitalization rates for PTB and IPD were decomposed into three components: a trend cycle component, a seasonal component and an irregular component using the X-11 seasonal adjustment method. To compare the seasonality amongst the three series, the trend and irregular components were removed and only seasonal components examined. Results Across the study period, the influenza virus epidemics peaked during May to July (winter) months, which was closely followed by an increase in the incidence of hospitalization for IPD (August to October) and PTB (August to November). Discussion Within- and between-year temporal changes associated with childhood TB hospitalization may in part be driven by factors which influence temporal changes in pneumococcal disease, including potential variability in the severity of influenza virus epidemics in temperate climates. The dynamics of the interplay between the host and these infectious agents appears to be complex and multifactorial.
Collapse
Affiliation(s)
- Ziyaad Dangor
- Medical Research Council, Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Department of Paediatrics, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Alane Izu
- Medical Research Council, Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases, University of the Witwatersrand, Johannesburg, South Africa
| | - David P. Moore
- Medical Research Council, Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases, University of the Witwatersrand, Johannesburg, South Africa
| | - Marta C. Nunes
- Medical Research Council, Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases, University of the Witwatersrand, Johannesburg, South Africa
| | - Fatima Solomon
- Medical Research Council, Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases, University of the Witwatersrand, Johannesburg, South Africa
| | - Natalie Beylis
- Mycobacteriology Referral Laboratory, National Health Laboratory Service, Johannesburg, South Africa
| | - Anne von Gottberg
- Center for Respiratory and Meningitis Diseases, National Institute for Communicable Diseases: A Division of National Health Laboratory Service, Sandringham, South Africa
| | - Johanna M. McAnerney
- Center for Respiratory and Meningitis Diseases, National Institute for Communicable Diseases: A Division of National Health Laboratory Service, Sandringham, South Africa
| | - Shabir A. Madhi
- Medical Research Council, Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases, University of the Witwatersrand, Johannesburg, South Africa
- Center for Respiratory and Meningitis Diseases, National Institute for Communicable Diseases: A Division of National Health Laboratory Service, Sandringham, South Africa
- * E-mail:
| |
Collapse
|
23
|
Pretreatment of epithelial cells with live Streptococcus pneumoniae has no detectable effect on influenza A virus replication in vitro. PLoS One 2014; 9:e90066. [PMID: 24594847 PMCID: PMC3940721 DOI: 10.1371/journal.pone.0090066] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2013] [Accepted: 01/29/2014] [Indexed: 12/16/2022] Open
Abstract
Influenza A virus (IAV) and Streptococcus pneumoniae (pneumococcus) are two major upper respiratory tract pathogens responsible for exacerbated disease in coinfected individuals. Despite several studies showing increased susceptibility to secondary bacterial infections following IAV infection, information on the direct effect of S. pneumoniae on IAV in vitro is unknown. This is an important area of investigation as S. pneumoniae is a common commensal of the human upper respiratory tract, present as an important coinfecting pathogen with IAV infection. A recent study showed that S. pneumoniae enhances human metapneumovirus infection in polarized bronchial epithelial cells in vitro. The aim of the current study was to determine whether treatment of epithelial cells with S. pneumoniae affects IAV replication using a standard immunofluorescence assay (IFA). For this study we used four IAV permissive epithelial cell lines including two human-derived cell lines, 12 pneumococcal strains including recent human clinical isolates which represent different genetic backgrounds and serotypes, and six IAV strains of varying genetic nature and pathogenic potential including the pandemic 2009 H1N1 virus. Our results suggested that pretreatment of MDCK cells with 7.5×106 colony-forming units (CFUs) of live S. pneumoniae resulted in gradual cell-death in a time-dependent manner (0.5 to 4 hr). But, pretreatment of cell lines with 7.5×105 and lower CFUs of S. pneumoniae had no detectable effect on either the morphology of cells or on the IAV replication. However, unlike in epithelial cell lines, due to influence of secreted host factors the effect of pneumococci on IAV replication may be different during coinfections in vivo in the human upper respiratory tract, and in vitro with primary human polarized bronchial epithelial cells.
Collapse
|
24
|
Michael P, Brabant D, Bleiblo F, Ramana CV, Rutherford M, Khurana S, Tai T, Kumar A, Kumar A. Influenza A induced cellular signal transduction pathways. J Thorac Dis 2013; 5 Suppl 2:S132-41. [PMID: 23977434 PMCID: PMC3747532 DOI: 10.3978/j.issn.2072-1439.2013.07.42] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2013] [Accepted: 07/25/2013] [Indexed: 12/28/2022]
Abstract
Influenza A is a negative sense single stranded RNA virus that belongs to the Orthomyxoviridae Family. This enveloped virus contains 8 segments of viral RNA which encodes 11 viral proteins. Influenza A infects humans and is the causative agent of the flu. Annually it infects approximately 5% to 15% of the population world wide and results in an estimated 250,000 to 500,000 deaths a year. The nature of influenza A replication results in a high mutation rate which results in the need for seasonal vaccinations. In addition the zoonotic nature of the influenza virus allows for recombination of viral segments from different strains creating new variants that have not been encountered before. This type of mutation is the method by which pandemic strains of the flu arises. Infection with influenza results in a respiratory illness that for most individuals is self limiting. However in susceptible populations which include individuals with pre-existing pulmonary or cardiac conditions, the very young and the elderly fatal complications may arise. The most serious of these is the development of viral pneumonia which may be accompanied by secondary bacterial infections. Progression of pneumonia leads to the development of acute respiratory distress syndrome (ARDS), acute lung injury (ALI) and potentially respiratory failure. This progression is a combined effect of the host immune system response to influenza infection and the viral infection itself. This review will focus on molecular aspects of viral replication in alveolar cells and their response to infection. The response of select innate immune cells and their contribution to viral clearance and lung epithelial damage will also be discussed. Molecular aspects of antiviral response in the cells in particular the protein kinase RNA dependent response, and the oligoadenylate synthetase RNAse L system in relation to influenza infection.
Collapse
Affiliation(s)
- Paul Michael
- Department of Chemistry and Biochemistry and the Biomolecular Sciences Program, Laurentian University, Sudbury, P3E 2C6, ON, Canada
| | - Danielle Brabant
- Department of Chemistry and Biochemistry and the Biomolecular Sciences Program, Laurentian University, Sudbury, P3E 2C6, ON, Canada
| | - Farag Bleiblo
- Department of Chemistry and Biochemistry and the Biomolecular Sciences Program, Laurentian University, Sudbury, P3E 2C6, ON, Canada
- Department of Biology, University of Benghazi, Benghazi, Libya
| | | | - Michael Rutherford
- Department of Pathology, Health Sciences North, Sudbury, P3E 5J1, ON, Canada
- Medical Sciences Division, Northern Ontario School of Medicine, Sudbury, P3E 2C6, ON, Canada
| | - Sandhya Khurana
- Department of Chemistry and Biochemistry and the Biomolecular Sciences Program, Laurentian University, Sudbury, P3E 2C6, ON, Canada
- Medical Sciences Division, Northern Ontario School of Medicine, Sudbury, P3E 2C6, ON, Canada
| | - T.C. Tai
- Department of Chemistry and Biochemistry and the Biomolecular Sciences Program, Laurentian University, Sudbury, P3E 2C6, ON, Canada
- Medical Sciences Division, Northern Ontario School of Medicine, Sudbury, P3E 2C6, ON, Canada
| | - Anand Kumar
- Section of Critical Care Medicine, University of Manitoba, Winnipeg, R3A 1R9, MB, Canada
| | - Aseem Kumar
- Department of Chemistry and Biochemistry and the Biomolecular Sciences Program, Laurentian University, Sudbury, P3E 2C6, ON, Canada
- Medical Sciences Division, Northern Ontario School of Medicine, Sudbury, P3E 2C6, ON, Canada
| |
Collapse
|
25
|
Lefebvre JS, Haynes L. Vaccine strategies to enhance immune responses in the aged. Curr Opin Immunol 2013; 25:523-8. [PMID: 23764092 DOI: 10.1016/j.coi.2013.05.014] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Revised: 05/20/2013] [Accepted: 05/21/2013] [Indexed: 12/20/2022]
Abstract
The elderly population is more susceptible to infections with higher risks of morbidity and mortality. This is caused by the accumulation of immune defects with aging. The best way to protect people against infections is vaccination. Unfortunately, the same immune defects that render the elderly susceptible to infectious diseases also prevent the development of protective immunity following immunization. A good example of this is the influenza vaccine that only protects between 40 and 60% of the vaccinees over 65 years. In the past decade, tremendous efforts have been put toward improving the influenza vaccine for the elderly. We therefore use this example to present various strategies employed to overcome these age-associated immune defects and hence make vaccines more efficacious for the aged.
Collapse
Affiliation(s)
- Julie S Lefebvre
- Trudeau Institute, 154 Algonquin Avenue, Saranac Lake, NY 12983, USA
| | | |
Collapse
|
26
|
Yin L, Calvo-Calle JM, Cruz J, Newman FK, Frey SE, Ennis FA, Stern LJ. CD4+ T cells provide intermolecular help to generate robust antibody responses in vaccinia virus-vaccinated humans. THE JOURNAL OF IMMUNOLOGY 2013; 190:6023-33. [PMID: 23667112 DOI: 10.4049/jimmunol.1202523] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Immunization with vaccinia virus elicits a protective Ab response that is almost completely CD4(+) T cell dependent. A recent study in a rodent model observed a deterministic linkage between Ab and CD4(+) T cell responses to particular vaccinia virus proteins suggesting that CD4(+) T cell help is preferentially provided to B cells with the same protein specificity (Sette et al. 2008. Immunity 28: 847-858). However, a causal linkage between Ab and CD4(+) T cell responses to vaccinia or any other large pathogen in humans has yet to be done. In this study, we measured the Ab and CD4(+) T cell responses against four vaccinia viral proteins (A27L, A33R, B5R, and L1R) known to be strongly targeted by humoral and cellular responses induced by vaccinia virus vaccination in 90 recently vaccinated and 7 long-term vaccinia-immunized human donors. Our data indicate that there is no direct linkage between Ab and CD4(+) T cell responses against each individual protein in both short-term and long-term immunized donors. Together with the observation that the presence of immune responses to these four proteins is linked together within donors, our data suggest that in vaccinia-immunized humans, individual viral proteins are not the primary recognition unit of CD4(+) T cell help for B cells. Therefore, we have for the first time, to our knowledge, shown evidence that CD4(+) T cells provide intermolecular (also known as noncognate or heterotypic) help to generate robust Ab responses against four vaccinia viral proteins in humans.
Collapse
Affiliation(s)
- Liusong Yin
- Department of Pathology, University of Massachusetts Medical School, Worcester, MA 01655, USA
| | | | | | | | | | | | | |
Collapse
|