scholarly journals Mechanism of Synthesis of Vaccinia Virus Double-Stranded Ribonucleic Acid In Vivo and In Vitro

1971 ◽  
Vol 7 (1) ◽  
pp. 71-76 ◽  
Author(s):  
Clarence Colby ◽  
Christine Jurale ◽  
Joseph R. Kates
Keyword(s):  
Vaccinia Virus ◽  
Ribonucleic Acid

scholarly journals Neutrophil subtypes shape HIV-specific CD8 T-cell responses after vaccinia virus infection

npj Vaccines ◽  
2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Mauro Di Pilato ◽  
Miguel Palomino-Segura ◽  
Ernesto Mejías-Pérez ◽  
Carmen E. Gómez ◽  
Andrea Rubio-Ponce ◽  
...  
Keyword(s):  
T Cell ◽  
Immune Responses ◽  
Vaccinia Virus ◽  
Adaptive Immune System ◽  
T Cell Responses ◽  
Cd8 T Cell ◽  
Cell Responses ◽  
Adaptive Immune

AbstractNeutrophils are innate immune cells involved in the elimination of pathogens and can also induce adaptive immune responses. Nα and Nβ neutrophils have been described with distinct in vitro capacity to generate antigen-specific CD8 T-cell responses. However, how these cell types exert their role in vivo and how manipulation of Nβ/Nα ratio influences vaccine-mediated immune responses are not known. In this study, we find that these neutrophil subtypes show distinct migratory and motility patterns and different ability to interact with CD8 T cells in the spleen following vaccinia virus (VACV) infection. Moreover, after analysis of adhesion, inflammatory, and migration markers, we observe that Nβ neutrophils overexpress the α4β1 integrin compared to Nα. Finally, by inhibiting α4β1 integrin, we increase the Nβ/Nα ratio and enhance CD8 T-cell responses to HIV VACV-delivered antigens. These findings provide significant advancements in the comprehension of neutrophil-based control of adaptive immune system and their relevance in vaccine design.

scholarly journals Heavily Isotype-Dependent Protective Activities of Human Antibodies against Vaccinia Virus Extracellular Virion Antigen B5

2009 ◽  
Vol 83 (23) ◽  
pp. 12355-12367 ◽  
Author(s):  
Mohammed Rafii-El-Idrissi Benhnia ◽  
Megan M. McCausland ◽  
John Laudenslager ◽  
Steven W. Granger ◽  
Sandra Rickert ◽  
...  
Keyword(s):  
Antibody Response ◽  
Vaccinia Virus ◽  
Smallpox Vaccine ◽  
Human Antibody ◽  
Human Mabs ◽  
Complement Components ◽  
Vaccinia Virion ◽  
Virion Antigen

ABSTRACT Antibodies against the extracellular virion (EV or EEV) form of vaccinia virus are an important component of protective immunity in animal models and likely contribute to the protection of immunized humans against poxviruses. Using fully human monoclonal antibodies (MAbs), we now have shown that the protective attributes of the human anti-B5 antibody response to the smallpox vaccine (vaccinia virus) are heavily dependent on effector functions. By switching Fc domains of a single MAb, we have definitively shown that neutralization in vitro—and protection in vivo in a mouse model—by the human anti-B5 immunoglobulin G MAbs is isotype dependent, thereby demonstrating that efficient protection by these antibodies is not simply dependent on binding an appropriate vaccinia virion antigen with high affinity but in fact requires antibody effector function. The complement components C3 and C1q, but not C5, were required for neutralization. We also have demonstrated that human MAbs against B5 can potently direct complement-dependent cytotoxicity of vaccinia virus-infected cells. Each of these results was then extended to the polyclonal human antibody response to the smallpox vaccine. A model is proposed to explain the mechanism of EV neutralization. Altogether these findings enhance our understanding of the central protective activities of smallpox vaccine-elicited antibodies in immunized humans.

scholarly journals Vaccinia Virus Envelope H3L Protein Binds to Cell Surface Heparan Sulfate and Is Important for Intracellular Mature Virion Morphogenesis and Virus Infection In Vitro and In Vivo

2000 ◽  
Vol 74 (7) ◽  
pp. 3353-3365 ◽  
Author(s):  
Chi-Long Lin ◽  
Che-Sheng Chung ◽  
Hans G. Heine ◽  
Wen Chang
Keyword(s):  
Cell Surface ◽  
Vaccinia Virus ◽  
Heparan Sulfate ◽  
Mutant Virus ◽  
Wild Type Virus ◽  
Type Virus ◽  
Wild Type ◽  
Virion Morphogenesis

ABSTRACT An immunodominant antigen, p35, is expressed on the envelope of intracellular mature virions (IMV) of vaccinia virus. p35 is encoded by the viral late gene H3L, but its role in the virus life cycle is not known. This report demonstrates that soluble H3L protein binds to heparan sulfate on the cell surface and competes with the binding of vaccinia virus, indicating a role for H3L protein in IMV adsorption to mammalian cells. A mutant virus defective in expression of H3L (H3L−) was constructed; the mutant virus has a small plaque phenotype and 10-fold lower IMV and extracellular enveloped virion titers than the wild-type virus. Virion morphogenesis is severely blocked and intermediate viral structures such as viral factories and crescents accumulate in cells infected with the H3L− mutant virus. IMV from the H3L− mutant virus are somewhat altered and less infectious than wild-type virions. However, cells infected by the mutant virus form multinucleated syncytia after low pH treatment, suggesting that H3L protein is not required for cell fusion. Mice inoculated intranasally with wild-type virus show high mortality and severe weight loss, whereas mice infected with H3L− mutant virus survive and recover faster, indicating that inactivation of the H3L gene attenuates virus virulence in vivo. In summary, these data indicate that H3L protein mediates vaccinia virus adsorption to cell surface heparan sulfate and is important for vaccinia virus infection in vitro and in vivo. In addition, H3L protein plays a role in virion assembly.

Identification of rpo30, a vaccinia virus RNA polymerase gene with structural similarity to a eucaryotic transcription elongation factor

1990 ◽  
Vol 10 (10) ◽  
pp. 5433-5441
Author(s):  
B Y Ahn ◽  
P D Gershon ◽  
E V Jones ◽  
B Moss
Keyword(s):  
Rna Polymerase ◽  
Vaccinia Virus ◽  
Rna Polymerase Ii ◽  
Elongation Factor ◽  
Viral Rna ◽  
In Vitro Translation ◽  
Virus Protein ◽  
Transcriptional Elongation

Eucaryotic transcription factors that stimulate RNA polymerase II by increasing the efficiency of elongation of specifically or randomly initiated RNA chains have been isolated and characterized. We have identified a 30-kilodalton (kDa) vaccinia virus-encoded protein with apparent homology to SII, a 34-kDa mammalian transcriptional elongation factor. In addition to amino acid sequence similarities, both proteins contain C-terminal putative zinc finger domains. Identification of the gene, rpo30, encoding the vaccinia virus protein was achieved by using antibody to the purified viral RNA polymerase for immunoprecipitation of the in vitro translation products of in vivo-synthesized early mRNA selected by hybridization to cloned DNA fragments of the viral genome. Western immunoblot analysis using antiserum made to the vaccinia rpo30 protein expressed in bacteria indicated that the 30-kDa protein remains associated with highly purified viral RNA polymerase. Thus, the vaccinia virus protein, unlike its eucaryotic homolog, is an integral RNA polymerase subunit rather than a readily separable transcription factor. Further studies showed that the expression of rpo30 is regulated by dual early and later promoters.

scholarly journals Modified Vaccinia Virus Ankara Triggers Chemotaxis of Monocytes and Early Respiratory Immigration of Leukocytes by Induction of CCL2 Expression

2009 ◽  
Vol 83 (6) ◽  
pp. 2540-2552 ◽  
Author(s):  
Michael H. Lehmann ◽  
Wolfgang Kastenmuller ◽  
Judith D. Kandemir ◽  
Florian Brandt ◽  
Yasemin Suezer ◽  
...  
Keyword(s):  
Vaccinia Virus ◽  
Viral Vector ◽  
Monocytic Cell ◽  
Monocytic Cell Line ◽  
Human Monocytic Cell Line ◽  
Modified Vaccinia Virus Ankara ◽  
Ccl2 Expression ◽  
Human Monocytic Cell

ABSTRACT Orthopoxviruses commonly enter into humans and animals via the respiratory tract. Herein, we show that immigration of leukocytes into the lung is triggered via intranasal infection of mice with modified vaccinia virus Ankara (MVA) and not with the vaccinia virus (VACV) Elstree, Wyeth, or Western Reserve (WR) strain. Immigrating cells were identified as monocytes, neutrophils, and CD4+ lymphocytes by flow cytometry and could be detected 24 h and 48 h postinfection. Using an in vitro chemotaxis assay, we confirmed that infection with MVA induces the expression of a soluble chemotactic factor for monocytes, identified as CCL2 (monocyte chemotactic protein-1 [MCP-1]). In contrast to infection with several other VACV strains, MVA induced the expression of CCL2, CCL3, CCL4, and CXCL10 in the human monocytic cell line THP-1 as well as in primary human monocytes. Thus, MVA, and not the VACV Elstree, Wyeth, or WR strain, consistently triggered the expression of a panel of chemokines, including CCL2, in the murine lung, correlating considerably with the immigration of leukocytes. Using CCL2-deficient mice, we demonstrate that CCL2 plays a key role in MVA-triggered respiratory immigration of leukocytes. Moreover, UV irradiation of MVA prevented CCL2 expression in vitro and in vivo as well as respiratory immigration of leukocytes, demonstrating the requirement for an activated molecular viral life cycle. We propose that MVA-triggered chemokine expression causes early immigration of leukocytes to the site of infection, a feature that is important for rapid immunization and its safety and efficiency as a viral vector.

scholarly journals ON THE ROLE OF RIBONUCLEIC ACID IN ANIMAL VIRUS SYNTHESIS

1960 ◽  
Vol 111 (3) ◽  
pp. 351-368 ◽  
Author(s):  
Igor Tamm ◽  
Rostom Bablanian
Keyword(s):  
Herpes Simplex ◽  
Vaccinia Virus ◽  
Ribonucleic Acid ◽  
Chorioallantoic Membrane ◽  
Host Cells ◽  
Active Inhibitor ◽  
Herpes Simplex Viruses ◽  
Virus Particles ◽  
Highly Active

Ribonuclease is a highly active inhibitor of vaccinia virus multiplication in vitro in the chorioallantoic membrane removed from embryonated chicken eggs. It is also a highly active inhibitor of pock formation by vaccinia and herpes simplex viruses on the chorioallantoic membrane in vivo. Marked inhibitory effects were obtained with 12.5 µg. of RNase. However, complete inhibition was not obtained with several hundred micrograms of the enzyme. RNase caused no inactivation of the infectivity of vaccinia virus particles but it had a marked inhibitory effect on multiplication of this virus when administered many hours after infection of host cells had occurred. RNase also failed to inactivate the infectivity of herpes simplex virus particles. The results obtained indicate that ribonucleic acid is necessary for the multiplication of two DNA-containing viruses; i.e., vaccinia and herpes simplex.

scholarly journals By Binding CD80 and CD86, the Vaccinia Virus M2 Protein Blocks Their Interactions with both CD28 and CTLA4 and Potentiates CD80 Binding to PD-L1

2019 ◽  
Vol 93 (11) ◽  
Author(s):  
Patricia Kleinpeter ◽  
Christelle Remy-Ziller ◽  
Eline Winter ◽  
Murielle Gantzer ◽  
Virginie Nourtier ◽  
...  
Keyword(s):  
Immune Response ◽  
Vaccinia Virus ◽  
Cytotoxic T Lymphocyte ◽  
Myxoma Virus ◽  
Parental Virus ◽  
M2 Protein ◽  
First Results ◽  
Infected Cells

ABSTRACTIn this article we report that the M2 protein encoded by the vaccinia virus is secreted as a homo-oligomer by infected cells and binds two central costimulation molecules, CD80 (B7-1) and CD86 (B7-2). These interactions block the ligation of the two B7 proteins to both soluble CD28 and soluble cytotoxic T-lymphocyte associated protein 4 (CTLA4) but favor the binding of soluble PD-L1 to soluble CD80. M2L gene orthologues are found in several other poxviruses, and the B7-CD28/CTLA4 blocking activity has been identified for several culture supernatants of orthopoxvirus-infected cells and for a recombinant myxoma virus M2 protein homolog (i.e., Gp120-like protein, or Gp120LP). Overall, these data indicate that the M2 poxvirus family of proteins may be involved in immunosuppressive activities broader than the NF-κB inhibition already reported (R. Gedey, X. L. Jin, O. Hinthong, and J. L. Shisler, J Virol 80:8676–8685, 2006, https://doi.org/10.1128/JVI.00935-06). A Copenhagen vaccinia virus with a deletion of the nonessential M2L locus was generated and compared with its parental virus. This M2L-deleted vaccinia virus, unlike the parental virus, does not generate interference with the B7-CD28/CTLA4/PD-L1 interactions. Moreover, this deletion did not affect any key features of the virus (in vitroreplication, oncolytic activitiesin vitroandin vivo,and intratumoral expression of a transgene in an immunocompetent murine model). Altogether, these first results suggest that the M2 protein has the potential to be used as a new immunosuppressive biotherapeutic and that the M2L-deleted vaccinia virus represents an attractive new oncolytic platform with an improved immunological profile.IMPORTANCEThe vaccinia virus harbors in its genome several genes dedicated to the inhibition of the host immune response. Among them, M2L was reported to inhibit the intracellular NF-κB pathway. We report here several new putative immunosuppressive activities of M2 protein. M2 protein is secreted and binds cornerstone costimulatory molecules (CD80/CD86). M2 binding to CD80/CD86 blocks their interaction with soluble CD28/CTLA4 but also favors the soluble PD-L1-CD80 association. These findings open the way for new investigations deciphering the immune system effects of soluble M2 protein. Moreover, a vaccinia virus with a deletion of its M2L has been generated and characterized as a new oncolytic platform. The replication and oncolytic activities of the M2L-deleted vaccinia virus are indistinguishable from those of the parental virus. More investigations are needed to characterize in detail the immune response triggered against both the tumor and the virus by this M2-defective vaccinia virus.

scholarly journals F11-Mediated Inhibition of RhoA Signalling Enhances the Spread of Vaccinia Virus In Vitro and In Vivo in an Intranasal Mouse Model of Infection

PLoS ONE ◽  
2009 ◽  
Vol 4 (12) ◽  
pp. e8506 ◽  
Author(s):  
João V. Cordeiro ◽  
Susana Guerra ◽  
Yoshiki Arakawa ◽  
Mark P. Dodding ◽  
Mariano Esteban ◽  
...  
Keyword(s):  
Mouse Model ◽  
Vaccinia Virus ◽  
Mouse Model Of Infection

scholarly journals Studies on the pathogenesis of liver necrosis by α-amanitin. Effect of α-amanitin on ribonucleic acid synthesis and on ribonucleic acid polymerase in mouse liver nuclei

1967 ◽  
Vol 105 (2) ◽  
pp. 779-782 ◽  
Author(s):  
F. Stirpe ◽  
L. Fiume
Keyword(s):  
Rna Polymerase ◽  
Ammonium Sulphate ◽  
Ribonucleic Acid ◽  
Mouse Liver ◽  
Orotic Acid ◽  
Acid Synthesis ◽  
Liver Necrosis ◽  
Liver Nuclei

1. Injection of α-amanitin to mice causes a decreased incorporation of [6−14C]-orotic acid into liver RNA in vivo. 2. The activity of RNA polymerase activated by Mn2+ and ammonium sulphate is greatly impaired in liver nuclei isolated from mice poisoned with α-amanitin, and is inhibited by the addition of the same toxin in vitro. 3. The activity of the Mg2+-activated RNA polymerase is only slightly affected by α-amanitin either administered to mice or added in vitro.

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