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1.
Hum Vaccin Immunother ; 17(2): 554-559, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-32750273

RESUMO

SeVRSV is a replication-competent Sendai virus (SeV)-based vaccine carrying the respiratory syncytial virus (RSV) fusion protein (F) gene. Unmanipulated, non-recombinant SeV is a murine parainfluenza virus type 1 (PIV-1) and serves as a Jennerian vaccine for human PIV-1 (hPIV-1). SeV protects African green monkeys (AGM) from infection after hPIV-1 challenge. The recombinant SeVRSV additionally targets RSV and protects AGM from lower respiratory infections after RSV challenge. The present study is the first to report on the safety, viral genome detection, and immunogenicity following SeVRSV vaccination of healthy adults. Seventeen and four healthy adults received intranasal SeVRSV and PBS, respectively, followed by six months of safety monitoring. Virus genome (in nasal wash) and vaccine-specific antibodies (in sera) were monitored for two and four weeks, respectively, post-vaccination. The vaccine was well-tolerated with only mild to moderate reactions that were also present in the placebo group. No severe reactions occurred. As expected, due to preexisting immunity toward hPIV-1 and RSV in adults, vaccine genome detection was transient. There were minimal antibody responses to SeV and negligible responses to RSV F. Results encourage further studies of SeVRSV with progression toward a clinical trial in seronegative children. Abbreviations: AE-adverse event; SAE-serious adverse event; SeV-Sendai virus; RSV-respiratory syncytial virus; PIV-1-parainfluenza virus-type 1; hPIV-1-human parainfluenza virus-type 1; F-RSV fusion protein; SeVRSV-recombinant SeV carrying the RSV F gene; Ab-antibody; MSW-medically significant wheezing; NOCMC-new onset chronic medical condition, mITT-modified Intent to Treat; ALRI-acute lower respiratory tract infection.


Assuntos
Infecções por Vírus Respiratório Sincicial , Vacinas contra Vírus Sincicial Respiratório , Vírus Sincicial Respiratório Humano , Adulto , Animais , Anticorpos Antivirais , Chlorocebus aethiops , Humanos , Imunogenicidade da Vacina , Vírus da Parainfluenza 1 Humana/genética , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Vacinas contra Vírus Sincicial Respiratório/efeitos adversos , Vacinas contra Vírus Sincicial Respiratório/genética , Vírus Sincicial Respiratório Humano/genética , Vírus Sendai/genética , Proteínas Virais de Fusão/genética
2.
Int Immunol ; 27(5): 229-36, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25477211

RESUMO

The respiratory syncytial virus (RSV) is responsible for as many as 199000 annual deaths worldwide. Currently, there is no standard treatment for RSV disease and no vaccine. Sendai virus (SeV) is an attractive pediatric vaccine candidate because it elicits robust and long-lasting virus-specific B cell and T cell activities in systemic and mucosal tissues. The virus serves as a gene delivery system as well as a Jennerian vaccine against its close cousin, human parainfluenza virus type 1. Here we describe the testing of a recombinant SeV (SeVRSV-Fs) that expresses an unconstrained, secreted RSV-F protein as a vaccine against RSV in cotton rats. After a single intranasal immunization of cotton rats with SeVRSV-Fs, RSV-specific binding and neutralizing antibodies were generated. These antibodies exhibited cross-reactivity with both RSV A and B isolates. RSV-F-specific IFN-γ-producing T cells were also activated. The SeVRSV-Fs vaccine conferred protection against RSV challenge without enhanced immunopathology. In total, results showed that an SeV recombinant that expresses RSV F in an unconstrained, soluble form can induce humoral and cellular immunity that protects against infection with RSV.


Assuntos
Infecções por Vírus Respiratório Sincicial/prevenção & controle , Vírus Sinciciais Respiratórios/metabolismo , Vírus Sendai/imunologia , Linfócitos T/imunologia , Vacinas Virais/administração & dosagem , Administração Intranasal , Animais , Anticorpos Antivirais/metabolismo , Modelos Animais de Doenças , Técnicas de Transferência de Genes , Humanos , Imunização , Interferon gama/metabolismo , Ativação Linfocitária , Ratos , Proteínas Recombinantes de Fusão/genética , Infecções por Vírus Respiratório Sincicial/imunologia , Vírus Sinciciais Respiratórios/genética , Vírus Sendai/genética , Sigmodontinae , Linfócitos T/virologia , Proteínas Virais de Fusão/genética , Vacinas Virais/genética
3.
Vaccine ; 30(5): 959-68, 2012 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-22119594

RESUMO

Respiratory syncytial virus (RSV) is a serious disease of children, responsible for an estimated 160,000 deaths per year worldwide. Despite the ongoing need for global prevention of RSV and decades of research, there remains no licensed vaccine. Sendai virus (SeV) is a mouse parainfluenza virus-type 1 which has been previously shown to confer protection against its human cousin, human parainfluenza virus-type 1 in African green monkeys (AGM). Here is described the study of a RSV vaccine (SeVRSV), produced by reverse genetics technology using SeV as a backbone to carry the full-length gene for RSV F. To test for immunogenicity, efficacy and safety, the vaccine was administered to AGM by intratracheal (i.t.) and intranasal (i.n.) routes. Control animals received the empty SeV vector or PBS. There were no booster immunizations. SeV and SeVRSV were cleared from the URT and LRT of vaccinated animals by day 10. Antibodies with specificities toward SeV and RSV were detected in SeVRSV primed animals as early as day ten after immunizations in both sera and nasal wash samples. One month after immunization all test and control AGM received an i.n. challenge with RSV-A2. SeVRSV-vaccinated animals exhibited reduced RSV in the URT compared to controls, and complete protection against RSV in the LRT. There were no clinically relevant adverse events associated with vaccination either before or after challenge. These data encourage advanced testing of the SeVRSV vaccine candidate in clinical trials for protection against RSV.


Assuntos
Portadores de Fármacos , Vetores Genéticos , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Vacinas contra Vírus Sincicial Respiratório/imunologia , Vírus Sendai/genética , Proteínas Virais de Fusão/genética , Proteínas Virais de Fusão/imunologia , Administração por Inalação , Administração Intranasal , Animais , Anticorpos Antivirais/sangue , Chlorocebus aethiops , Modelos Animais de Doenças , Vacinas contra Vírus Sincicial Respiratório/administração & dosagem , Vacinas contra Vírus Sincicial Respiratório/efeitos adversos , Vacinas contra Vírus Sincicial Respiratório/genética , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/efeitos adversos , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia
4.
J Virol ; 84(2): 810-21, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19906935

RESUMO

While the molecular basis of fusion (F) protein refolding during membrane fusion has been studied extensively in vitro, little is known about the biological significance of membrane fusion activity in parainfluenza virus replication and pathogenesis in vivo. Two recombinant Sendai viruses, F-L179V and F-K180Q, were generated that contain F protein mutations in the heptad repeat A region of the ectodomain, a region of the protein known to regulate F protein activation. In vitro, the F-L179V virus caused increased syncytium formation (cell-cell membrane fusion) yet had a rate of replication and levels of F protein expression and cleavage similar to wild-type virus. The F-K180Q virus had a reduced replication rate along with reduced levels of F protein expression, cleavage, and fusogenicity. In DBA/2 mice, the hyperfusogenic F-L179V virus induced greater morbidity and mortality than wild-type virus, while the attenuated F-K180Q virus was much less pathogenic. During the first week of infection, virus replication and inflammation in the lungs were similar for wild-type and F-L179V viruses. After approximately 1 week of infection, the clearance of F-L179V virus was delayed, and more extensive interstitial inflammation and necrosis were observed in the lungs, affecting entire lobes of the lungs and having significantly greater numbers of syncytial cell masses in alveolar spaces on day 10. On the other hand, the slower-growing F-K180Q virus caused much less extensive inflammation than wild-type virus, presumably due to its reduced replication rate, and did not cause observable syncytium formation in the lungs. Overall, the results show that residues in the heptad repeat A region of the F protein modulate the virulence of Sendai virus in mice by influencing both the spread and clearance of the virus and the extent and severity of inflammation. An understanding of how the F protein contributes to infection and inflammation in vivo may assist in the development of antiviral therapies against respiratory paramyxoviruses.


Assuntos
Regulação Viral da Expressão Gênica , Vírus Sendai/patogenicidade , Proteínas Virais de Fusão/química , Animais , Linhagem Celular , Chlorocebus aethiops , Feminino , Pulmão/patologia , Pulmão/virologia , Fusão de Membrana/fisiologia , Camundongos , Camundongos Endogâmicos DBA , Mutação Puntual , Infecções por Respirovirus/mortalidade , Infecções por Respirovirus/fisiopatologia , Infecções por Respirovirus/virologia , Vírus Sendai/genética , Vírus Sendai/metabolismo , Células Vero , Proteínas Virais de Fusão/metabolismo , Virulência
5.
J Virol ; 82(17): 8400-10, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18579600

RESUMO

BCX 2798 (4-azido-5-isobutyrylamino-2,3-didehydro-2,3,4,5-tetradeoxy-d-glycero-d-galacto-2-nonulopyranosic acid) effectively inhibited the activities of the hemagglutinin-neuraminidase (HN) of human parainfluenza viruses (hPIV) in vitro and protected mice from lethal infection with a recombinant Sendai virus whose HN was replaced with that of hPIV-1 (rSeV[hPIV-1HN]) (I. V. Alymova, G. Taylor, T. Takimoto, T. H. Lin., P. Chand, Y. S. Babu, C. Li, X. Xiong, and A. Portner, Antimicrob. Agents Chemother. 48:1495-1502, 2004). The ability of BCX 2798 to select drug-resistant variants in vivo was examined. A variant with an Asn-to-Ser mutation at residue 173 (N173S) in HN was recovered from mice after a second passage of rSeV(hPIV-1HN) in the presence of BCX 2798 (10 mg/kg of body weight daily). The N173S mutant remained sensitive to BCX 2798 in neuraminidase inhibition assays but was more than 10,000-fold less sensitive to the compound in hemagglutination inhibition tests than rSeV(hPIV-1HN). Its susceptibility to BCX 2798 in plaque reduction assays was reduced fivefold and did not differ from that of rSeV(hPIV-1HN) in mice. The N173S mutant failed to be efficiently eluted from erythrocytes and released from cells. It demonstrated reduced growth in cell culture and superior growth in mice. The results for gel electrophoresis analysis were consistent with the loss of the N-linked glycan at residue 173 in the mutant. Sequence and structural comparisons revealed that residue 173 on hPIV-1 HN is located close to the region of the second receptor-binding site identified in Newcastle disease virus HN. Our study suggests that the N-linked glycan at residue 173 masks a second receptor-binding site on hPIV-1 HN.


Assuntos
Proteína HN/genética , Vírus da Parainfluenza 1 Humana/genética , Vírus da Parainfluenza 1 Humana/metabolismo , Sítios de Ligação , Linhagem Celular Tumoral , Proteína HN/química , Humanos , Cinética , Modelos Moleculares , Mutação , Vírus da Parainfluenza 1 Humana/química , Vírus da Parainfluenza 1 Humana/ultraestrutura , Receptores Virais/metabolismo
6.
Vaccine ; 26(27-28): 3480-8, 2008 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-18499307

RESUMO

The human parainfluenza viruses (hPIVs) and respiratory syncytial virus (RSV) are the leading causes of serious respiratory illness in the human pediatric population. Despite decades of research, there are currently no licensed vaccines for either the hPIV or RSV pathogens. Here we describe the testing of hPIV-3 and RSV candidate vaccines using Sendai virus (SeV, murine PIV-1) as a vector. SeV was selected as the vaccine backbone, because it has been shown to elicit robust and durable immune activities in animal studies, and has already advanced to human safety trials as a xenogenic vaccine for hPIV-1. Two new SeV-based hPIV-3 vaccine candidates were first generated by inserting either the fusion (F) gene or hemagglutinin-neuraminidase (HN) gene from hPIV-3 into SeV. The resultant rSeV-hPIV3-F and rSeV-hPIV3-HN vaccines expressed their inserted hPIV-3 genes upon infection. The inoculation of either vaccine into cotton rats elicited binding and neutralizing antibody activities, as well as interferon-gamma-producing T cells. Vaccination of cotton rats resulted in protection against subsequent challenges with either homologous or heterologous hPIV-3. Furthermore, vaccination of cotton rats with a mixture of rSeV-hPIV3-HN and a previously described recombinant SeV expressing the F protein of RSV resulted in protection against three different challenge viruses: hPIV-3, hPIV-1 and RSV. Results encourage the continued development of the candidate recombinant SeV vaccines to combat serious respiratory infections of children.


Assuntos
Proteína HN/imunologia , Vacinas contra Parainfluenza/imunologia , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Vacinas contra Vírus Sincicial Respiratório/imunologia , Infecções por Respirovirus/prevenção & controle , Vírus Sendai/genética , Proteínas Virais de Fusão/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Antivirais/sangue , Feminino , Vetores Genéticos , Proteína HN/genética , Pulmão/virologia , Dados de Sequência Molecular , Vacinas contra Parainfluenza/genética , Ratos , Vacinas contra Vírus Sincicial Respiratório/genética , Sigmodontinae , Linfócitos T/imunologia , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Proteínas Virais de Fusão/genética
7.
Vaccine ; 25(52): 8782-93, 2007 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-18037543

RESUMO

The respiratory syncytial virus (RSV) is a serious pediatric pathogen for which there is currently no clinically approved vaccine. This report describes the design and testing of a new RSV vaccine construct (rSV-RSV-F), created by the recombination of an RSV F sequence with the murine parainfluenza virus-type 1 (Sendai virus, SV) genome. SV was selected as the vaccine backbone for this study, because it has previously been shown to elicit high-magnitude, durable immune activities in animal studies and has advanced to human safety trials as a xenogenic vaccine for human parainfluenza virus-type 1 (hPIV-1). Cells infected with the recombinant SV expressed RSV F protein, but F was not incorporated into progeny SV virions. When cotton rats were inoculated with the vaccine, high-titer RSV-binding and neutralizing antibodies as well as interferon-gamma-producing T-cells were induced. Most striking was the protection against intra-nasal RSV challenge conferred by the vaccine. The rSV-RSV-F construct was also tested as a mixture with a second SV construct expressing the RSV G protein, but no clear advantage was demonstrated by combining the two vaccines. As a final analysis, the efficacy of the rSV-RSV-F vaccine was tested against an array of RSV isolates. Results showed that neutralizing and protective responses were effective against RSV isolates of both A and B subtypes. Together, experimental results encourage promotion of this recombinant SV construct as a vaccine candidate for the prevention of RSV in humans.


Assuntos
Infecções por Vírus Respiratório Sincicial/prevenção & controle , Vírus Sinciciais Respiratórios/imunologia , Vírus Sendai/imunologia , Proteínas Virais de Fusão/imunologia , Vacinas Virais/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Antivirais/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Interferon gama/biossíntese , Pulmão/patologia , Pulmão/virologia , Dados de Sequência Molecular , Testes de Neutralização , Infecções por Vírus Respiratório Sincicial/imunologia , Infecções por Vírus Respiratório Sincicial/patologia , Vírus Sinciciais Respiratórios/genética , Vírus Sendai/genética , Sigmodontinae , Linfócitos T/imunologia , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/imunologia , Proteínas Virais de Fusão/genética , Ensaio de Placa Viral , Vacinas Virais/genética
8.
J Med Microbiol ; 56(Pt 9): 1133-1137, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17761473

RESUMO

Respiratory syncytial virus (RSV) infection is associated with secondary bacterial infections caused by nontypeable Haemophilus influenzae (NTHi) and Streptococcus pneumoniae. The pathogenesis of these complications is not completely understood; however, viral infection of respiratory epithelial cells promotes colonization by these bacteria. In the present study, RSV virions associated with NTHi and pneumococci in an inoculum-dependent manner in a fluid-phase binding assay. Adherence of NTHi and S. pneumoniae to epithelial cells transiently expressing RSV G glycoprotein was 2- and 2.2-fold higher, respectively, than adhesion to cells transfected with the vector alone (P <0.01). Furthermore, 4.6- and 6.2-fold larger numbers of NTHi and pneumococci bound to cells expressing a membrane-bound full-length RSV G protein than to cells expressing a truncated non-membrane-bound protein (P

Assuntos
Aderência Bacteriana/fisiologia , Haemophilus influenzae/fisiologia , Streptococcus pneumoniae/fisiologia , Proteínas Virais de Fusão/metabolismo , Animais , Células CHO , Cricetinae , Cricetulus , Células Epiteliais/microbiologia , Células Epiteliais/virologia , Infecções por Haemophilus/microbiologia , Haemophilus influenzae/classificação , Infecções Pneumocócicas/microbiologia , Ligação Proteica , Infecções por Vírus Respiratório Sincicial/complicações
9.
J Virol ; 80(11): 5145-55, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16698995

RESUMO

Newcastle disease virus (NDV) is a negative-strand RNA virus with oncolytic activity against human tumors. Its effectiveness against tumors and safety in normal tissue have been demonstrated in several clinical studies. Here we show that the spread of NDV infection is drastically different in normal cell lines than in tumor cell lines and that the two cell types respond differently to beta interferon (IFN-beta) treatment. NDV rapidly replicated and killed HT-1080 human fibrosarcoma cells but spread poorly in CCD-1122Sk human skin fibroblast cells. Pretreatment with endogenous or exogenous IFN-beta completely inhibited NDV replication in normal cells but had little or no effect in tumor cells. Thus, the outcome of NDV infection appeared to depend on the response of uninfected cells to IFN-beta. To investigate their differences in IFN responsiveness, we analyzed and compared the expression and activation of components of the IFN signal transduction pathway in these two types of cells. The levels of phosphorylated STAT1 and STAT2 and that of the ISGF3 complex were markedly reduced in IFN-beta-treated tumor cells. Moreover, cDNA microarray analysis revealed significantly fewer IFN-regulated genes in the HT-1080 cells than in the CDD-1122Sk cells. This finding suggests that tumor cells demonstrate a less-than-optimum antiviral response because of a lesion in their IFN signal transduction pathway. The rapid spread of NDV in HT-1080 cells appears to be caused by their deficient expression of anti-NDV proteins upon exposure to IFN-beta.


Assuntos
Interferons/biossíntese , Doença de Newcastle/fisiopatologia , Vírus da Doença de Newcastle/fisiologia , Proteínas Virais/fisiologia , Animais , Linhagem Celular , Regulação Viral da Expressão Gênica , Interferons/imunologia , Células Tumorais Cultivadas/metabolismo , Células Tumorais Cultivadas/virologia , Proteínas Virais/genética
10.
Antimicrob Agents Chemother ; 48(5): 1495-502, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15105096

RESUMO

Human parainfluenza viruses are important respiratory tract pathogens, especially of children. However, no vaccines or specific therapies for infections caused by these viruses are currently available. In the present study we characterized the efficacy of the novel parainfluenza virus inhibitors BCX 2798 and BCX 2855, which were designed based on the three-dimensional structure of the hemagglutinin-neuraminidase (HN) protein. The compounds were highly effective in inhibiting hemagglutinin (HA) and neuraminidase (NA) activities and the growth of hPIV-1, hPIV-2, and hPIV-3 in LLC-MK(2) cells. The concentrations required to reduce the activity to 50% of that of a control ranged from 0.1 to 6.0 micro M in HA inhibition assays and from 0.02 to 20 micro M in NA inhibition assays. The concentrations required to inhibit virus replication to 50% of the level of the control ranged from 0.7 to 11.5 micro M. BCX 2798 and BCX 2855 were inactive against influenza virus HA and NA and bacterial NA. In mice infected with a recombinant Sendai virus whose HN gene was replaced with that of hPIV-1 [rSV(hHN)], intranasal administration of BCX 2798 (10 mg/kg per day) and of BCX 2855 (50 mg/kg per day) 4 h before the start of infection resulted in a significant reduction in titers of virus in the lungs and protection from death. Treatment beginning 24 h after the start of infection did not prevent death. Together, our results indicate that BCX 2798 and BCX 2855 are effective inhibitors of parainfluenza virus HN and may limit parainfluenza virus infections in humans.


Assuntos
Antivirais/farmacologia , Azidas/farmacologia , Inibidores Enzimáticos/farmacologia , Hemaglutininas/efeitos dos fármacos , Ácidos Hexurônicos/farmacologia , Neuraminidase/antagonistas & inibidores , Vírus da Parainfluenza 1 Humana/efeitos dos fármacos , Vírus da Parainfluenza 2 Humana/efeitos dos fármacos , Vírus da Parainfluenza 3 Humana/efeitos dos fármacos , Sulfonamidas/farmacologia , Animais , Feminino , Humanos , Células LLC-PK1 , Pulmão/patologia , Pulmão/virologia , Camundongos , Infecções por Paramyxoviridae/tratamento farmacológico , Infecções por Paramyxoviridae/patologia , Infecções por Paramyxoviridae/virologia , Proteínas Recombinantes , Vírus Sendai/efeitos dos fármacos , Vírus Sendai/genética , Suínos , Proteínas Virais de Fusão/efeitos dos fármacos , Proteínas Virais de Fusão/genética , Replicação Viral/efeitos dos fármacos
11.
J Virol ; 76(24): 13028-33, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12438628

RESUMO

Paramyxovirus infects cells by initially attaching to a sialic acid-containing cellular receptor and subsequently fusing with the plasma membrane of the cells. Hemagglutinin-neuraminidase (HN) protein, which is responsible for virus attachment, interacts with the fusion protein in a virus type-specific manner to induce efficient membrane fusion. To elucidate the mechanism of HN-promoted membrane fusion, we characterized a series of Newcastle disease virus HN proteins whose surface residues were mutated. Fusion promotion activity was substantially altered in only the HN proteins with a mutation in the first or sixth beta sheet. These regions overlap the large hydrophobic surface of HN; thus, the hydrophobic surface may contain the fusion promotion domain. Furthermore, a comparison of the HN structure crystallized alone or in complex with 2-deoxy-2,3-dehydro-N-acetylneuraminic acid revealed substantial conformational changes in several loops within or near the hydrophobic surface. Our results suggest that the binding of HN protein to the receptor induces the conformational change of residues near the hydrophobic surface of HN protein and that this change triggers the activation of the F protein, which initiates membrane fusion.


Assuntos
Proteína HN/fisiologia , Fusão de Membrana/fisiologia , Vírus da Doença de Newcastle/fisiologia , Dimerização , Proteína HN/química , Células HeLa , Humanos , Conformação Proteica , Proteínas Virais de Fusão/fisiologia
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