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1.
Transbound Emerg Dis ; 69(3): 1375-1386, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-33835709

RESUMEN

The SARS-CoV-2 virus has been rapidly spreading globally since December 2019, triggering a pandemic, soon after its emergence. While Iran was among the first countries confronted with rapid spread of virus in February 2020, no real-time SARS-CoV-2 whole-genome tracking in early phase of outbreak was performed in the country. To address this issue, we provided 50 whole-genome sequences of viral isolates ascertained from different geographical locations in Iran during March-July 2020. The corresponding analysis on origins, transmission dynamics and genetic diversity of SARS-CoV-2 virus, represented at least two introductions of the virus into the country, constructing two major clusters defined as B.4 and B.1*. The first entry of the virus might have occurred around very late 2019/early 2020, as suggested by the time to the most recent common ancestor, followed by a rapid community transmission that led to dominancy of B.4 lineage in early epidemic till the end of June. Gradually, reduction in dominancy of B.4 occurred possibly as a result of other entries of the virus, followed by surge of B.1* lineages, as of mid-May. Remarkably, variation tracking of the virus indicated the increase in frequency of D614G mutation, along with B.1* lineages, which showed continuity till October 2020. The increase in frequency of D614G mutation and B.1* lineages from mid-May onwards predicts a rapid viral transmission that may push the country into a critical health situation followed by a considerable change in composition of viral lineages circulating in the country.


Asunto(s)
COVID-19 , SARS-CoV-2 , Animales , COVID-19/epidemiología , COVID-19/veterinaria , Brotes de Enfermedades/veterinaria , Genoma Viral , Irán/epidemiología , Filogenia , SARS-CoV-2/genética
2.
Infect Agent Cancer ; 16(1): 69, 2021 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-34922563

RESUMEN

BACKGROUND: Despite recent advancements, limitations in the treatment and control of hepatitis C virus (HCV) infection reprioritized the studies for invention of an efficient HCV vaccine to elicit strong neutralizing antibodies (NAbs) and cellular responses. METHODS: Herein, we report molecular construction of a BacMam virus-based surface display for a subtype-1a HCV gpE2 (Bac-CMV-E2-gp64; Bac) that both expressed and displayed gpE2 in mammalian cells and bacouloviral envelope, respectively. RESULTS: Assessments by western blotting, Immunofluorescence and Immunogold-electron microscopy indicated the proper expression and incorporation in insect cell and baculovirus envelope, respectively. Mice immunized in three different prime-boost immunization groups of: Bac/Bac, Bac/Pro (bacoulovirus-derived gpE2) and Bac/DNA (plasmid DNA (pCDNA)-encoding gpE2) developed high levels of IgG and IFN-γ (highest for Bac/Bac group) indicating the induction of both humeral and cellular immune responses. Calculation of the IgG2a/IgG1 and IFN-γ/IL-4 ratios indicated a Th1 polarization of immune responses in the Bac/Bac and Bac/DNA groups but a balanced Th1-Th2 phenotype in the Bac/Pro group. Sera of the mice in the Bac/Bac group provided the highest percentage of cross-NAbs against a subtype-2a HCVcc (JFH1) compared to Bac/Pro and Bac/DNA groups (62% versus 41% and 6%). CONCLUSIONS: Results indicated that BacMam virus-based surface display for gpE2 might act as both subunit and DNA vaccine and offers a promising strategy for development of HCV vaccine for concurrent induction of strong humoral and cellular immune responses.

3.
Med Microbiol Immunol ; 207(1): 65-74, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29147974

RESUMEN

Hepatitis C virus (HCV) modulates immune-related inflammatory responses to induce milder reactions leading to virus persistence. In this regard, the present study aimed to investigate the link between the HCV genotypes and the proinflammatory and regulatory cytokine levels. Ninety patients with hepatitis C infection (68 treatment-naive and 22 treated patients) and 76 healthy blood donors were studied. The serum levels of IFN-γ, IL-10, IL-17A, and IL-21 were measured by ELISA in the patients and healthy controls. IL-10, IL-17A, and IL-21 levels were significantly higher in HCV patients than in the healthy controls. The same cytokines were also higher in genotype 3a-infected patients compared with genotype 1a-infected patients. Interestingly, in treated patients, lower serum levels of IL-17A and IL-21 were detected in G3a-infected individuals, but not in those infected with G1a. G3a viral load displayed a significant correlation with IL-21 and IL-17A levels. In addition, G1a viral load correlated with IL-10 levels. In G3a-infected patients, a significant association was found between IL-17A serum levels and ALT. We found differences in IL-21 and IL-17A serum levels among HCV-infected patients which were genotype dependent. Since Th17-associated cytokines are associated with the progression of liver disease in HCV patients, IL-17A and IL-21 can be used as important biological markers for evaluating the immunopathogenesis of chronic hepatitis. Our results suggest that HCV G3a along with immune responses such as cytokines in HCV patients should be taken into account when interpreting clinical data and IFN-based therapeutic response.


Asunto(s)
Citocinas/sangre , Genotipo , Hepacivirus/clasificación , Hepacivirus/inmunología , Hepatitis C Crónica/patología , Hepatitis C Crónica/virología , Adulto , Anciano , Anciano de 80 o más Años , Antivirales/uso terapéutico , Ensayo de Inmunoadsorción Enzimática , Femenino , Hepacivirus/genética , Hepacivirus/aislamiento & purificación , Hepatitis C Crónica/tratamiento farmacológico , Humanos , Interferones/uso terapéutico , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Carga Viral , Adulto Joven
4.
Trop Anim Health Prod ; 46(3): 549-54, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24389885

RESUMEN

Highly pathogenic avian influenza (HPAI) H5N1 virus is causing the death of a large number of wild birds and poultry. HPAI H5N1 was reported in the north of Iran in 2011. In this study, two A/Chicken/Iran/271/2011 and A/Duck/Iran/178/2011 viruses were genetically characterized by sequence analysis of Hemagglutinin (HA) and Neuraminidase (NA) genes. Phylogenetic analysis revealed that these viruses were different from previous Iranian isolates (Clade 2.2) and belonged to the subclade 2.3.2.1. The results showed that the detected viruses are almost identical to each other and closely related to HPAI H5N1 strains isolated in Mongolia in 2010. Based on the amino acid sequence analysis, these viruses at their HA cleavage sites contained the multibasic amino acid motif PQRERRRK-R/GLF lacking a lysine residue compared with the previous reports of the same motif. There is also a 20-amino acid deletion (resides 49-69) in the NA stalk similar to other viruses isolated after 2000. It seems that introduction of HPAI H5N1 to Iran might have happened by wild birds from Mongolian origin virus.


Asunto(s)
Hemaglutininas/genética , Subtipo H5N1 del Virus de la Influenza A/metabolismo , Gripe Aviar/virología , Glicoproteínas de Membrana/genética , Neuraminidasa/genética , Animales , Animales Salvajes/genética , Aves , Regulación Viral de la Expresión Génica/fisiología , Hemaglutininas/metabolismo , Subtipo H5N1 del Virus de la Influenza A/genética , Gripe Aviar/epidemiología , Irán , Glicoproteínas de Membrana/metabolismo , Neuraminidasa/metabolismo , Filogenia
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