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1.
Cell ; 187(6): 1363-1373.e12, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38366591

RESUMO

In response to the 2022 outbreak of mpox driven by unprecedented human-to-human monkeypox virus (MPXV) transmission, we designed BNT166, aiming to create a highly immunogenic, safe, accessible, and scalable next-generation vaccine against MPXV and related orthopoxviruses. To address the multiple viral forms and increase the breadth of immune response, two candidate multivalent mRNA vaccines were evaluated pre-clinically: a quadrivalent vaccine (BNT166a; encoding the MPXV antigens A35, B6, M1, H3) and a trivalent vaccine (BNT166c; without H3). Both candidates induced robust T cell responses and IgG antibodies in mice, including neutralizing antibodies to both MPXV and vaccinia virus. In challenge studies, BNT166a and BNT166c provided complete protection from vaccinia, clade I, and clade IIb MPXV. Furthermore, immunization with BNT166a was 100% effective at preventing death and at suppressing lesions in a lethal clade I MPXV challenge in cynomolgus macaques. These findings support the clinical evaluation of BNT166, now underway (NCT05988203).


Assuntos
Monkeypox virus , Mpox , Vacina Antivariólica , Animais , Humanos , Camundongos , Macaca fascicularis , Monkeypox virus/genética , Mpox/imunologia , Mpox/prevenção & controle , Vacinas Combinadas , Vaccinia virus/genética
2.
Cell ; 186(11): 2392-2409.e21, 2023 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-37164012

RESUMO

T cell responses play an important role in protection against beta-coronavirus infections, including SARS-CoV-2, where they associate with decreased COVID-19 disease severity and duration. To enhance T cell immunity across epitopes infrequently altered in SARS-CoV-2 variants, we designed BNT162b4, an mRNA vaccine component that is intended to be combined with BNT162b2, the spike-protein-encoding vaccine. BNT162b4 encodes variant-conserved, immunogenic segments of the SARS-CoV-2 nucleocapsid, membrane, and ORF1ab proteins, targeting diverse HLA alleles. BNT162b4 elicits polyfunctional CD4+ and CD8+ T cell responses to diverse epitopes in animal models, alone or when co-administered with BNT162b2 while preserving spike-specific immunity. Importantly, we demonstrate that BNT162b4 protects hamsters from severe disease and reduces viral titers following challenge with viral variants. These data suggest that a combination of BNT162b2 and BNT162b4 could reduce COVID-19 disease severity and duration caused by circulating or future variants. BNT162b4 is currently being clinically evaluated in combination with the BA.4/BA.5 Omicron-updated bivalent BNT162b2 (NCT05541861).


Assuntos
Vacina BNT162 , COVID-19 , Animais , Cricetinae , Humanos , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Epitopos , SARS-CoV-2/genética
3.
Nature ; 592(7853): 283-289, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33524990

RESUMO

A safe and effective vaccine against COVID-19 is urgently needed in quantities that are sufficient to immunize large populations. Here we report the preclinical development of two vaccine candidates (BNT162b1 and BNT162b2) that contain nucleoside-modified messenger RNA that encodes immunogens derived from the spike glycoprotein (S) of SARS-CoV-2, formulated in lipid nanoparticles. BNT162b1 encodes a soluble, secreted trimerized receptor-binding domain (known as the RBD-foldon). BNT162b2 encodes the full-length transmembrane S glycoprotein, locked in its prefusion conformation by the substitution of two residues with proline (S(K986P/V987P); hereafter, S(P2) (also known as P2 S)). The flexibly tethered RBDs of the RBD-foldon bind to human ACE2 with high avidity. Approximately 20% of the S(P2) trimers are in the two-RBD 'down', one-RBD 'up' state. In mice, one intramuscular dose of either candidate vaccine elicits a dose-dependent antibody response with high virus-entry inhibition titres and strong T-helper-1 CD4+ and IFNγ+CD8+ T cell responses. Prime-boost vaccination of rhesus macaques (Macaca mulatta) with the BNT162b candidates elicits SARS-CoV-2-neutralizing geometric mean titres that are 8.2-18.2× that of a panel of SARS-CoV-2-convalescent human sera. The vaccine candidates protect macaques against challenge with SARS-CoV-2; in particular, BNT162b2 protects the lower respiratory tract against the presence of viral RNA and shows no evidence of disease enhancement. Both candidates are being evaluated in phase I trials in Germany and the USA1-3, and BNT162b2 is being evaluated in an ongoing global phase II/III trial (NCT04380701 and NCT04368728).


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/imunologia , COVID-19/prevenção & controle , Modelos Animais de Doenças , SARS-CoV-2/imunologia , Envelhecimento/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Antígenos Virais/química , Antígenos Virais/genética , Antígenos Virais/imunologia , Vacina BNT162 , COVID-19/sangue , COVID-19/terapia , COVID-19/virologia , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/química , Vacinas contra COVID-19/genética , Linhagem Celular , Ensaios Clínicos como Assunto , Feminino , Humanos , Imunização Passiva , Internacionalidade , Macaca mulatta/imunologia , Macaca mulatta/virologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Multimerização Proteica , RNA Viral/análise , Sistema Respiratório/imunologia , Sistema Respiratório/virologia , SARS-CoV-2/química , SARS-CoV-2/genética , Solubilidade , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Linfócitos T/imunologia , Vacinação , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/química , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Soroterapia para COVID-19 , Vacinas de mRNA
4.
Mol Ther ; 26(2): 446-455, 2018 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-29275847

RESUMO

New vaccine platforms are needed to address the time gap between pathogen emergence and vaccine licensure. RNA-based vaccines are an attractive candidate for this role: they are safe, are produced cell free, and can be rapidly generated in response to pathogen emergence. Two RNA vaccine platforms are available: synthetic mRNA molecules encoding only the antigen of interest and self-amplifying RNA (sa-RNA). sa-RNA is virally derived and encodes both the antigen of interest and proteins enabling RNA vaccine replication. Both platforms have been shown to induce an immune response, but it is not clear which approach is optimal. In the current studies, we compared synthetic mRNA and sa-RNA expressing influenza virus hemagglutinin. Both platforms were protective, but equivalent levels of protection were achieved using 1.25 µg sa-RNA compared to 80 µg mRNA (64-fold less material). Having determined that sa-RNA was more effective than mRNA, we tested hemagglutinin from three strains of influenza H1N1, H3N2 (X31), and B (Massachusetts) as sa-RNA vaccines, and all protected against challenge infection. When sa-RNA was combined in a trivalent formulation, it protected against sequential H1N1 and H3N2 challenges. From this we conclude that sa-RNA is a promising platform for vaccines against viral diseases.


Assuntos
Vírus da Influenza A/imunologia , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , RNA Viral/imunologia , Animais , Modelos Animais de Doenças , Feminino , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Humanos , Imunização , Imunização Secundária , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A/genética , Vacinas contra Influenza/genética , Camundongos , RNA Mensageiro/genética , RNA Mensageiro/imunologia , RNA Viral/genética , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
5.
Infect Immun ; 82(3): 993-1006, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24343651

RESUMO

The obligate intracellular bacterial pathogen Chlamydia trachomatis is the causative agent of a variety of infectious diseases such as trachoma and sexually transmitted diseases. In infected target cells, C. trachomatis replicates within parasitophorous vacuoles and expresses the protease-like activity factor CPAF. Previous studies have suggested that CPAF degrades the host transcription factors RFX5 and NF-κB p65, which are involved in the regulation of constitutive and inducible expression of major histocompatibility complex class I (MHC I). It was speculated that Chlamydia suppresses the surface presentation of MHC I in order to evade an effective immune response. Nevertheless, a recent study suggested that RFX5 and NF-κB p65 may not serve as target substrates for CPAF-mediated degradation, raising concerns about the proposed MHC I subversion by Chlamydia. Hence, we investigated the direct influence of Chlamydia on MHC I expression and surface presentation in infected host cells. By using nine different human cells and cell lines infected with C. trachomatis (serovar D or LGV2), we demonstrate that chlamydial infection does not interfere with expression, maturation, transport, and surface presentation of MHC I, suggesting functional antigen processing in bacterium-infected cells. Our findings provide novel insights into the interaction of chlamydiae with their host cells and should be taken into consideration for the design of future therapies and vaccines.


Assuntos
Infecções por Chlamydia/imunologia , Chlamydia trachomatis/imunologia , Células Epiteliais/imunologia , Células Epiteliais/microbiologia , Fibroblastos/imunologia , Fibroblastos/microbiologia , Genes MHC Classe I/imunologia , Linhagem Celular Tumoral , Células HeLa , Humanos , Células MCF-7
6.
Front Immunol ; 15: 1360698, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38979428

RESUMO

Regulatory T cells (Tregs) play a crucial and complex role in balancing the immune response to viral infection. Primarily, they serve to regulate the immune response by limiting the expression of proinflammatory cytokines, reducing inflammation in infected tissue, and limiting virus-specific T cell responses. But excessive activity of Tregs can also be detrimental and hinder the ability to effectively clear viral infection, leading to prolonged disease and potential worsening of disease severity. Not much is known about the impact of Tregs during severe influenza. In the present study, we show that CD4+/CD25+FoxP3+ Tregs are strongly involved in disease progression during influenza A virus (IAV) infection in mice. By comparing sublethal with lethal dose infection in vivo, we found that not the viral load but an increased number of CD4+/CD25+FoxP3+ Tregs may impair the immune response by suppressing virus specific CD8+ T cells and favors disease progression. Moreover, the transfer of induced Tregs into mice with mild disease symptoms had a negative and prolonged effect on disease outcome, emphasizing their importance for pathogenesis. Furthermore, treatment with MEK-inhibitors resulted in a significant reduction of induced Tregs in vitro and in vivo and positively influenced the progression of the disease. Our results demonstrate that CD4+/CD25+FoxP3+ Tregs are involved in the pathogenesis of severe influenza and indicate the potential of the MEK-inhibitor zapnometinib to modulate CD4+/CD25+FoxP3+ Tregs. Thus, making MEK-inhibitors even more promising for the treatment of severe influenza virus infections.


Assuntos
Vírus da Influenza A , Infecções por Orthomyxoviridae , Linfócitos T Reguladores , Animais , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/efeitos dos fármacos , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/tratamento farmacológico , Camundongos , Vírus da Influenza A/imunologia , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Feminino , Camundongos Endogâmicos C57BL , Fatores de Transcrição Forkhead/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Carga Viral/efeitos dos fármacos , Modelos Animais de Doenças
7.
Vaccines (Basel) ; 11(2)2023 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-36851293

RESUMO

The emergence of SARS-CoV-2 at the end of 2019 required the swift development of a vaccine to address the pandemic. Nonclinical GLP-compliant studies in Wistar Han rats were initiated to assess the local tolerance, systemic toxicity, and immune response to four mRNA vaccine candidates encoding immunogens derived from the spike (S) glycoprotein of SARS-CoV-2, encapsulated in lipid nanoparticles (LNPs). Vaccine candidates were administered intramuscularly once weekly for three doses at 30 and/or 100 µg followed by a 3-week recovery period. Clinical pathology findings included higher white blood cell counts and acute phase reactant concentrations, lower platelet and reticulocyte counts, and lower RBC parameters. Microscopically, there was increased cellularity (lymphocytes) in the lymph nodes and spleen, increased hematopoiesis in the bone marrow and spleen, acute inflammation and edema at the injection site, and minimal hepatocellular vacuolation. These findings were generally attributed to the anticipated immune and inflammatory responses to the vaccines, except for hepatocyte vacuolation, which was interpreted to reflect hepatocyte LNP lipid uptake, was similar between candidates and resolved or partially recovered at the end of the recovery phase. These studies demonstrated safety and tolerability in rats, supporting SARS-CoV-2 mRNA-LNP vaccine clinical development.

8.
Mol Ther Nucleic Acids ; 34: 102045, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37876532

RESUMO

The response to mRNA vaccines needs to be sufficient for immune cell activation and recruitment, but moderate enough to ensure efficacious antigen expression. The choice of the cap structure and use of N1-methylpseudouridine (m1Ψ) instead of uridine, which have been shown to reduce RNA sensing by the cellular innate immune system, has led to improved efficacy of mRNA vaccine platforms. Understanding how RNA modifications influence the cell intrinsic immune response may help in the development of more effective mRNA vaccines. In the current study, we compared mRNA vaccines in mice against influenza virus using three different mRNA formats: uridine-containing mRNA (D1-uRNA), m1Ψ-modified mRNA (D1-modRNA), and D1-modRNA with a cap1 structure (cC1-modRNA). D1-uRNA vaccine induced a significantly different gene expression profile to the modified mRNA vaccines, with an up-regulation of Stat1 and RnaseL, and increased systemic inflammation. This result correlated with significantly reduced antigen-specific antibody responses and reduced protection against influenza virus infection compared with D1-modRNA and cC1-modRNA. Incorporation of m1Ψ alone without cap1 improved antibodies, but both modifications were required for the optimum response. Therefore, the incorporation of m1Ψ and cap1 alters protective immunity from mRNA vaccines by altering the innate immune response to the vaccine material.

9.
J Immunol ; 185(8): 4824-34, 2010 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-20861351

RESUMO

Highly pathogenic avian influenza viruses (HPAIVs) cause severe disease in humans. Still, the basis for their increased pathogenesis remains unclear. Additionally, the high morbidity in the younger population stays inexplicable, and the recent pandemic H1N1v outbreak in 2009 demonstrated the urgent need for a better understanding about influenza virus infection. In the present study, we demonstrated that HPAIV infection of mice not only led to lung destruction but also to functional damage of the thymus. Moreover, respiratory dendritic cells in the lung functioned as targets for HPAIV infection being able to transport infectious virus from the lung into the thymus. The pandemic H1N1 influenza virus was able to infect respiratory dendritic cells without a proper transport to the thymus. The strong interference of HPAIV with the immune system is especially devastating for the host and can lead to lymphopenia. In summary, from our data, we conclude that highly pathogenic influenza viruses are able to reach the thymus via dendritic cells and to interfere with T lymphocyte development. Moreover, this exceptional mechanism might not only be found in influenza virus infection, but also might be the reason for the increased immune evasion of some new emerging pathogens.


Assuntos
Células Dendríticas/virologia , Infecções por Orthomyxoviridae/imunologia , Linfócitos T/citologia , Timo/imunologia , Timo/virologia , Animais , Contagem de Células , Separação Celular , Quimiotaxia de Leucócito/imunologia , Citometria de Fluxo , Imunofluorescência , Imuno-Histoquímica , Vírus da Influenza A/imunologia , Pulmão/imunologia , Pulmão/virologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Linfócitos T/imunologia , Timo/citologia
10.
Sci Immunol ; 7(78): eade9888, 2022 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-36378074

RESUMO

The SARS-CoV-2 Omicron variant and its sublineages show pronounced viral escape from neutralizing antibodies elicited by vaccination or prior SARS-CoV-2 variant infection owing to over 30-amino acid alterations within the spike (S) glycoprotein. Breakthrough infection of vaccinated individuals with Omicron sublineages BA.1 and BA.2 is associated with distinct patterns of cross-neutralizing activity against SARS-CoV-2 variants of concern (VOCs). In continuation of our previous work, we characterized the effect of Omicron BA.4/BA.5 S glycoprotein exposure on the neutralizing antibody response upon breakthrough infection in vaccinated individuals and upon variant-adapted booster vaccination in mice. We found that immune sera from triple mRNA-vaccinated individuals with subsequent breakthrough infection during the Omicron BA.4/BA.5 wave showed cross-neutralizing activity against previous Omicron variants BA.1, BA.2, BA.2.12.1, and BA.4/BA.5 itself. Administration of a prototypic BA.4/BA.5-adapted mRNA booster vaccine to mice after SARS-CoV-2 wild-type strain-based primary immunization is associated with broader cross-neutralizing activity than a BA.1-adapted booster. Whereas the Omicron BA.1-adapted mRNA vaccine in a bivalent format (wild-type + BA.1) broadens cross-neutralizing activity relative to the BA.1 monovalent booster, cross-neutralization of BA.2 and descendants is more effective in mice boosted with a bivalent wild-type + BA.4/BA.5 vaccine. In naïve mice, primary immunization with the bivalent wild-type + Omicron BA.4/BA.5 vaccine induces strong cross-neutralizing activity against Omicron VOCs and previous variants. These findings suggest that, when administered as boosters, mono- and bivalent Omicron BA.4/BA.5-adapted vaccines enhance neutralization breadth and that the bivalent version also has the potential to confer protection to individuals with no preexisting immunity against SARS-CoV-2.


Assuntos
COVID-19 , Vacinas , Humanos , Animais , Camundongos , SARS-CoV-2 , COVID-19/prevenção & controle , Anticorpos Neutralizantes , Infecções Irruptivas , RNA Mensageiro
11.
Stroke ; 42(3): 783-91, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21293018

RESUMO

BACKGROUND AND PURPOSE: Stroke is triggered by several risk factors, including influenza and other respiratory tract infections. However, it is unknown how and in which way influenza infection affects stroke outcome. METHODS: We infected mice intranasally with human influenza A (H1N1) virus and occluded the middle cerebral artery to induce ischemic strokes. Infarct volume and intracerebral hemorrhage were determined by histology. To evaluate the integrity of the blood-brain barrier and inflammation, we measured various cytokines in vivo and in vitro and performed immunohistochemistry of leukocyte markers, collagen IV, immunoglobulins, and matrix metalloproteinase-9. RESULTS: Influenza virus infection increased infarct size. Whereas changes in cardiovascular parameters did not explain this effect, we found evidence for an inflammatory mechanism. In influenza virus infection, the respiratory tract released cytokines into the blood, such as RANTES that induced macrophage inflammatory protein-2 and other inflammatory mediators in the ischemic brain. In infected mice, there was an increased number of neutrophils expressing the matrix metalloproteinase-9 in the ischemic brain. This was accompanied by severe disruption of the blood-brain barrier and an increased rate of intracerebral hemorrhages after tissue plasminogen activator treatment. To investigate the role of cytokines, we blocked cytokine release by using GTS-21, a selective agonist of the α7 nicotinic acetylcholine receptor. GTS-21 ameliorated ischemic brain damage and improved survival. CONCLUSIONS: Influenza virus infection triggers a cytokine cascade that aggravates ischemic brain damage and increases the risk of intracerebral hemorrhage after tissue plasminogen activator treatment. Blockade of cytokine production by α7 nicotinic acetylcholine receptor agonists is a novel therapeutic option to treat stroke in a proinflammatory context.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Influenza Humana/complicações , Acidente Vascular Cerebral/complicações , Animais , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Barreira Hematoencefálica/virologia , Quimiocina CCL5/antagonistas & inibidores , Quimiocina CCL5/metabolismo , Quimiocina CXCL2/antagonistas & inibidores , Quimiocina CXCL2/metabolismo , Humanos , Inflamação/complicações , Inflamação/metabolismo , Inflamação/patologia , Vírus da Influenza A Subtipo H1N1/patogenicidade , Influenza Humana/metabolismo , Influenza Humana/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Distribuição Aleatória , Fatores de Risco , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/patologia , Resultado do Tratamento
12.
Vaccines (Basel) ; 9(4)2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33915773

RESUMO

BNT162b2 is a highly efficacious mRNA vaccine approved to prevent COVID-19. This brief report describes the immunogenicity and anti-viral protective effect of BNT162b2 in hACE2 transgenic mice. Prime-boost immunization with BNT162b2 elicited high titers in neutralizing antibodies against SARS-CoV-2, which correlated with viral clearance and alleviated lung lesions in these mice after viral challenge.

13.
Mol Ther Nucleic Acids ; 25: 483-493, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34589271

RESUMO

Self-amplifying mRNA (saRNA) represents a promising platform for nucleic acid delivery of vaccine immunogens. Unlike plasmid DNA, saRNA does not require entry into the nucleus of target cells for expression, having the capacity to drive higher protein expression compared to mRNA as it replicates within the cytoplasm. In this study, we examined the potential of stabilized native-like HIV-1 Envelope glycoprotein (Env) trimers to elicit immune responses when delivered by saRNA polyplexes (PLXs), assembled with linear polyethylenimine. We showed that Venezuelan equine encephalitis virus (VEEV) saRNA induces a stronger humoral immune response to the encoded transgene compared to Semliki Forest virus saRNA. Moreover, we characterized the immunogenicity of the soluble and membrane-bound ConSOSL.UFO Env design in mice and showed a faster humoral kinetic and an immunoglobulin G (IgG)2a skew using a membrane-bound design. The immune response generated by PLX VEEV saRNA encoding the membrane-bound Env was then evaluated in larger animal models including macaques, in which low doses induced high IgG responses. Our data demonstrated that the VEEV saRNA PLX nanoparticle formulation represents a suitable platform for the delivery of stabilized HIV-1 Env and has the potential to be used in a variety of vaccine regimens.

14.
Mol Ther Methods Clin Dev ; 12: 32-46, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30547051

RESUMO

Focusing T cell responses on the most vulnerable parts of HIV-1, the functionally conserved regions of HIV-1 proteins, is likely a key prerequisite for vaccine success. For a T cell vaccine to efficiently control HIV-1 replication, the vaccine-elicited individual CD8+ T cells and as a population have to display a number of critical traits. If any one of these traits is suboptimal, the vaccine is likely to fail. Fine-tuning of individual protective characteristics of T cells will require iterative stepwise improvements in clinical trials. Although the second-generation tHIVconsvX immunogens direct CD8+ T cells to predominantly protective and conserved epitopes, in the present work, we have used formulated self-amplifying mRNA (saRNA) to deliver tHIVconsvX to the immune system. We demonstrated in BALB/c and outbred mice that regimens employing saRNA vaccines induced broadly specific, plurifunctional CD8+ and CD4+ T cells, which displayed structured memory subpopulations and were maintained at relatively high frequencies over at least 22 weeks post-administration. This is one of the first thorough analyses of mRNA vaccine-elicited T cell responses. The combination of tHIVconsvX immunogens and the highly versatile and easily manufacturable saRNA platform may provide a long-awaited opportunity to define and optimize induction of truly protective CD8+ T cell parameters in human volunteers.

16.
PLoS Negl Trop Dis ; 10(6): e0004746, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27336830

RESUMO

Rabies is a zoonotic infectious disease of the central nervous system (CNS). In unvaccinated or untreated subjects, rabies virus infection causes severe neurological symptoms and is invariably fatal. Despite the long-standing existence of effective vaccines, vaccine availability remains insufficient, with high numbers of fatal infections mostly in developing countries. Nucleic acid based vaccines have proven convincingly as a new technology for the fast development of vaccines against newly emerging pathogens, diseases where no vaccine exists or for replacing already existing vaccines. We used an optimized non-replicating rabies virus glycoprotein (RABV-G) encoding messenger RNA (mRNA) to induce potent neutralizing antibodies (VN titers) in mice and domestic pigs. Functional antibody titers were followed in mice for up to one year and titers remained stable for the entire observation period in all dose groups. T cell analysis revealed the induction of both, specific CD4+ as well as CD8+ T cells by RABV-G mRNA, with the induced CD4+ T cells being higher than those induced by a licensed vaccine. Notably, RABV-G mRNA vaccinated mice were protected against lethal intracerebral challenge infection. Inhibition of viral replication by vaccination was verified by qRT-PCR. Furthermore, we demonstrate that CD4+ T cells are crucial for the generation of neutralizing antibodies. In domestic pigs we were able to induce VN titers that correlate with protection in adult and newborn pigs. This study demonstrates the feasibility of a non-replicating mRNA rabies vaccine in small and large animals and highlights the promises of mRNA vaccines for the prevention of infectious diseases.


Assuntos
Glicoproteínas/imunologia , Fragmentos de Peptídeos/imunologia , RNA Mensageiro/imunologia , Vacina Antirrábica , Raiva/veterinária , Doenças dos Suínos/prevenção & controle , Proteínas Virais/imunologia , Animais , Animais Recém-Nascidos , Sequência de Bases , Relação Dose-Resposta Imunológica , Feminino , Células HeLa , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Gravidez , RNA Mensageiro/química , Raiva/mortalidade , Raiva/prevenção & controle , Vacina Antirrábica/genética , Vacina Antirrábica/imunologia , Suínos , Linfócitos T , Vacinas Sintéticas/imunologia
17.
J Clin Invest ; 123(1): 206-14, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23202729

RESUMO

Influenza causes substantial morbidity and mortality, and highly pathogenic and drug-resistant strains are likely to emerge in the future. Protease-activated receptor 1 (PAR1) is a thrombin-activated receptor that contributes to inflammatory responses at mucosal surfaces. The role of PAR1 in pathogenesis of virus infections is unknown. Here, we demonstrate that PAR1 contributed to the deleterious inflammatory response after influenza virus infection in mice. Activating PAR1 by administering the agonist TFLLR-NH2 decreased survival and increased lung inflammation after influenza infection. Importantly, both administration of a PAR1 antagonist and PAR1 deficiency protected mice from infection with influenza A viruses (IAVs). Treatment with the PAR1 agonist did not alter survival of mice deficient in plasminogen (PLG), which suggests that PLG permits and/or interacts with a PAR1 function in this model. PAR1 antagonists are in human trials for other indications. Our findings suggest that PAR1 antagonism might be explored as a treatment for influenza, including that caused by highly pathogenic H5N1 and oseltamivir-resistant H1N1 viruses.


Assuntos
Vírus da Influenza A Subtipo H1N1/patogenicidade , Virus da Influenza A Subtipo H5N1/patogenicidade , Infecções por Orthomyxoviridae/tratamento farmacológico , Infecções por Orthomyxoviridae/imunologia , Receptor PAR-1/imunologia , Animais , Cães , Humanos , Influenza Humana/tratamento farmacológico , Influenza Humana/genética , Influenza Humana/imunologia , Camundongos , Camundongos Knockout , Células NIH 3T3 , Oligopeptídeos/farmacologia , Infecções por Orthomyxoviridae/genética , Infecções por Orthomyxoviridae/patologia , Plasminogênio/genética , Plasminogênio/imunologia , Receptor PAR-1/agonistas , Receptor PAR-1/antagonistas & inibidores , Receptor PAR-1/genética
18.
Nat Biotechnol ; 30(12): 1210-6, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23159882

RESUMO

Despite substantial improvements, influenza vaccine production-and availability-remain suboptimal. Influenza vaccines based on mRNA may offer a solution as sequence-matched, clinical-grade material could be produced reliably and rapidly in a scalable process, allowing quick response to the emergence of pandemic strains. Here we show that mRNA vaccines induce balanced, long-lived and protective immunity to influenza A virus infections in even very young and very old mice and that the vaccine remains protective upon thermal stress. This vaccine format elicits B and T cell-dependent protection and targets multiple antigens, including the highly conserved viral nucleoprotein, indicating its usefulness as a cross-protective vaccine. In ferrets and pigs, mRNA vaccines induce immunological correlates of protection and protective effects similar to those of a licensed influenza vaccine in pigs. Thus, mRNA vaccines could address substantial medical need in the area of influenza prophylaxis and the broader realm of anti-infective vaccinology.


Assuntos
Vírus da Influenza A/genética , Vírus da Influenza A/imunologia , Vacinas contra Influenza/genética , Vacinas contra Influenza/imunologia , RNA Mensageiro/genética , RNA Mensageiro/imunologia , Envelhecimento/imunologia , Animais , Animais Recém-Nascidos , Linfócitos B/imunologia , Biotecnologia , Proteção Cruzada , Feminino , Furões , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Dados de Sequência Molecular , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , RNA Viral/genética , RNA Viral/imunologia , Ratos , Ratos Endogâmicos Lew , Sus scrofa , Linfócitos T/imunologia , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia
19.
J Interferon Cytokine Res ; 31(6): 515-25, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21323570

RESUMO

The recent emergence of pandemic swine-origin influenza virus (H1N1) and the severe outbreaks of highly pathogenic avian influenza virus of the H5N1 subtype leading to death in humans is a reminder that influenza remains a frightening foe throughout the world. Besides vaccination, there is an urgent need for new antiviral strategies to protect against influenza. The innate immune response to influenza viruses involves production of interferon alpha and beta (IFN-α/ß), which plays a crucial role in virus clearance during the initial stage of infection. We examined the effect of IFN-α on the replication of H5N1 and H1N1 in vitro and in vivo. A single pretreatment with low-dose IFN-α reduced lung virus titers up to 1.4 log(10) pfu. The antiviral effect increased after multiple pretreatments. Low-dose IFN-α protected mice against lethal H5N1 viral infection. Further, IFN-α was also effective against H1N1 in vitro and in the mouse model. These results indicate that low-dose IFN-α treatment leads to the induction of antiviral cytokines that are involved in the reduction of influenza virus titers in the lung. Moreover, it might be possible that a medical application during pandemic outbreak could help contain fulminant infections.


Assuntos
Células Epiteliais/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/fisiologia , Virus da Influenza A Subtipo H5N1/fisiologia , Influenza Humana/tratamento farmacológico , Interferon Tipo I/administração & dosagem , Infecções por Orthomyxoviridae/tratamento farmacológico , Animais , Aves , Linhagem Celular Tumoral , Progressão da Doença , Células Epiteliais/imunologia , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Células Epiteliais/virologia , Fibroblastos/imunologia , Fibroblastos/metabolismo , Fibroblastos/patologia , Fibroblastos/virologia , Humanos , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/patogenicidade , Virus da Influenza A Subtipo H5N1/efeitos dos fármacos , Virus da Influenza A Subtipo H5N1/patogenicidade , Influenza Aviária/virologia , Influenza Humana/imunologia , Influenza Humana/virologia , Interferon Tipo I/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/fisiopatologia , Infecções por Orthomyxoviridae/virologia , Proteínas Recombinantes , Especificidade da Espécie , Suínos , Replicação Viral/efeitos dos fármacos
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