IU Indianapolis ScholarWorks :: Browsing by Subject "Vaccinia virus"

Browsing by Subject "Vaccinia virus"

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Engineering Oncolytic Vaccinia Virus to redirect Macrophages to Tumor Cells
(Wiley, 2021) Cao, Felicia; Nguyen, Phuong; Hong, Bangxing; DeRenzo, Christopher; Rainusso, Nino C.; Rodriguez Cruz, Tania; Wu, Meng-Fen; Liu, Hao; Song, Xiao-Tong; Suzuki, Masataka; Wang, Lisa L.; Yustein, Jason T.; Gottschalk, Stephen; Biostatistics and Health Data Science, School of Medicine
Oncolytic virotherapy has been tested in numerous early phase clinical studies. However, the antitumor activity of oncolytic viruses thus far has been limited. Numerous strategies are being explored to enhance their antitumor activity by activating the adaptive arm of the immune system. We reasoned that it might also be possible to engineer oncolytic viruses to redirect tumor-associated macrophages to tumor cells for therapeutic benefit. We engineered an oncolytic vaccinia virus (VV) to disrupt the CD47/SIRPα interaction by expressing a chimeric molecule that consists of the ectodomain of SIRPα and the Fc domain of IgG4 (SIRPα-Fc-VV). SIRPα-Fc-VV readily replicated in tumor cells and redirected M1 as well as M2 macrophages to tumor cells in vitro. In contrast, control VVs that either encoded YFP (YFP-VV) or SIRPα (SIRPα-VV) did not. In vivo, SIRPα-Fc-VV had greater antitumor activity than YFP-VV and SIRPα-VV in an immune competent osteosarcoma model resulting in a significant survival advantage. Pretreatment with cytoxan further augmented the antitumor activity of SIRPα-Fc-VV. Thus, arming oncolytic viruses with SIRPα-Fc may present a promising strategy to enhance their antitumor activity for the virotherapy of solid tumors.
Primary Human B Cells at Different Differentiation and Maturation Stages Exhibit Distinct Susceptibilities to Vaccinia Virus Binding and Infection
(American Society for Microbiology, 2019-09-12) Shepherd, Nicole; Lan, Jie; Rane, Sushmita; Yu, Qigui; Microbiology and Immunology, School of Medicine
Vaccinia virus (VACV), the prototypical member of the poxvirus family, was used as a live-virus vaccine to eradicate smallpox worldwide and has recently received considerable attention because of its potential as a prominent vector for the development of vaccines against infectious diseases and as an oncolytic virus for cancer therapy. Studies have demonstrated that VACV exhibits an extremely strong bias for binding to and infection of primary human antigen-presenting cells (APCs), including monocytes, macrophages, and dendritic cells. However, very few studies have assessed the interactions of VACV with primary human B cells, a main type of professional APCs. In this study, we evaluated the susceptibility of primary human peripheral B cells at various differentiation and maturation stages to VACV binding, infection, and replication. We found that plasmablasts were resistant to VACV binding, while other B subsets, including transitional, mature naive, memory, and plasma cells, were highly susceptible to VACV binding. VACV binding preference was likely associated with differential expression of chemokine receptors, particularly CXCR5. Infection studies showed that plasmablast, plasma, transitional, and mature naive B cells were resistant to VACV infection, while memory B cells were preferentially infected. VACV infection in ex vivo B cells was abortive, which occurred at the stage of late viral gene expression. In contrast, activated B cells were permissive to productive VACV infection. Thus, primary human B cells at different differentiation stages exhibit distinct susceptibilities to VACV binding and infection, and the infections are abortive and productive in ex vivo and activated B cells, respectively. IMPORTANCE Our results provide critical information to the field of poxvirus binding and infection tropism. We demonstrate that VACV preferentially infects memory B cells that play an important role in a rapid and vigorous antibody-mediated immune response upon reinfection by a pathogen. Additionally, this work highlights the potential of B cells as natural cellular models to identify VACV receptors or dissect the molecular mechanisms underlying key steps of the VACV life cycle, such as binding, penetration, entry, and replication in primary human cells. The understanding of VACV biology in human primary cells is essential for the development of a safe and effective live-virus vector for oncolytic virus therapy and vaccines against smallpox, other pathogens, and cancer.
Primary Human Macrophages Serve as Vehicles for Vaccinia Virus Replication and Dissemination
(American Society for Microbiology (ASM), 2014-06) Byrd, Daniel; Shepherd, Nicole; Lan, Jie; Hu, Ningjie; Amet, Tohti; Yang, Kai; Desai, Mona; Yu, Qigui; Department of Microbiology & Immunology, IU School of Medicine
Human monocytic and professional antigen-presenting cells have been reported only to exhibit abortive infections with vaccinia virus (VACV). We found that monocyte-derived macrophages (MDMs), including granulocyte macrophage colony-stimulating factor (GM-CSF)-polarized M1 and macrophage colony-stimulating factor (M-CSF)-polarized M2, but not human AB serum-derived cells, were permissive to VACV replication. The titers of infectious virions in both cell-free supernatants and cellular lysates of infected M1 and M2 markedly increased in a time-dependent manner. The majority of virions produced in permissive MDMs were extracellular enveloped virions (EEV), a secreted form of VACV associated with long-range virus dissemination, and were mainly found in the culture supernatant. Infected MDMs formed VACV factories, actin tails, virion-associated branching structures, and cell linkages, indicating that MDMs are able to initiate de novo synthesis of viral DNA and promote virus release. VACV replication was sensitive to inhibitors against the Akt and Erk1/2 pathways that can be activated by VACV infection and M-CSF stimulation. Classical activation of MDMs by lipopolysaccharide (LPS) plus gamma interferon (IFN-γ) stimulation caused no effect on VACV replication, while alternative activation of MDMs by interleukin-10 (IL-10) or LPS-plus-IL-1β treatment significantly decreased VACV production. The IL-10-mediated suppression of VACV replication was largely due to Stat3 activation, as a Stat3 inhibitor restored virus production to levels observed without IL-10 stimulation. In conclusion, our data demonstrate that primary human macrophages are permissive to VACV replication. After infection, these cells produce EEV for long-range dissemination and also form structures associated with virions which may contribute to cell-cell spread. IMPORTANCE Our results provide critical information to the burgeoning fields of cancer-killing (oncolytic) virus therapy with vaccinia virus (VACV). One type of macrophage (M2) is considered a common presence in tumors and is associated with poor prognosis. Our results demonstrate a preference for VACV replication in M2 macrophages and could assist in designing treatments and engineering poxviruses with special considerations for their effect on M2 macrophage-containing tumors. Additionally, this work highlights the importance of macrophages in the field of vaccine development using poxviruses as vectors. The understanding of the dynamics of poxvirus-infected foci is central in understanding the effectiveness of the immune response to poxvirus-mediated vaccine vectors. Monocytic cells have been found to be an important part of VACV skin lesions in mice in controlling the infection as well as mediating virus transport out of infected foci.
Vaccina Virus Binding and Infection of Primary Human B Cells
(2018-12) Shepherd, Nicole Elizabeth; Yu, Andy Qigui; Androphy, Elliot J.; Blum, Janice S.; Serezani, Henrique
Vaccinia virus (VACV), the prototypical poxvirus, was used to eradicate smallpox worldwide and, in recent years, has received considerable attention as a vector for the development of vaccines against infectious diseases and oncolytic virus therapy. Studies have demonstrated that VACV exhibits an extremely strong bias for binding to and infection of primary human antigenpresenting cells (APCs) including monocytes, macrophages, and dendritic cells. However, very few studies have evaluated VACV binding to and infection of primary human B cells, a main type of professional APC. In this study, we evaluated the susceptibility of primary human peripheral B cells at different developmental stages to VACV binding, infection, and replication. We found that VACV exhibited strong binding but little entry into ex vivo B cells. Phenotypic analysis of B cells revealed that plasmablasts were the only subset resistant to VACV binding. Infection studies showed that plasma and mature-naïve B cells were resistant to VACV infection, while memory B cells were preferentially infected. Additionally, VACV infection was increased in larger and proliferative B cells suggesting a bias of VACV infection towards specific stages of differentiation and proliferative ability. VACV infection in B cells was abortive, and cessation of VACV infection was determined to occur at the stage of late viral gene expression. Interestingly, B cell function, measured by cytokine production, was not affected within 24 hours post-infection. In contrast to ex vivo B cells, stimulated B cells were permissive to productive VACV infection. These results demonstrate the value of B cells as a tool to aid in deciphering the intricacies of poxvirus infection in humans. Understanding VACV infection in primary human B cells at various stages of differentiation and maturation is important for the development of a safer smallpox vaccine and better vectors for vaccines against cancers and other infectious diseases.
Vaccinia Virus Binding and Infection of Primary Human Leukocytes
(2014) Byrd, Daniel James; Yu, Andy; Brutkiewicz, Randy R.; Cornetta, Kenneth G.; Kaplan, Mark H.
Vaccinia virus (VV) is the prototypical member of the orthopoxvirus genus of the Poxviridae family, and is currently being evaluated as a vector for vaccine development and cancer cell-targeting therapy. Despite the importance of studying poxvirus effects on the human immune system, reports of the direct interactions between poxviruses and primary human leukocytes (PHLs) are limited. We studied the specific molecular events that determine the VV tropism for major PHL subsets including monocytes, B cells, neutrophils, NK cells, and T cells. We found that VV exhibited an extremely strong bias towards binding and infecting monocytes among PHLs. VV binding strongly co-localized with lipid rafts on the surface of these cell types, even when lipid rafts were relocated to the cell uropods upon cell polarization. In humans, monocytic and professional antigen-presenting cells (APCs) have so far only been reported to exhibit abortive infections with VV. We found that monocyte-derived macrophages (MDMs), including granulocyte macrophage colony-stimulating factor (GM-CSF)-polarized M1 and macrophage colony-stimulating factor (M-CSF)-polarized M2, were permissive to VV replication. The majority of virions produced in MDMs were extracellular enveloped virions (EEV). Visualization of infected MDMs revealed the formation of VV factories, actin tails, virion-associated branching structures and cell linkages, indicating that infected MDMs are able to initiate de novo synthesis of viral DNA and promote virus release. Classical activation of MDMs by LPS plus IFN-γ stimulation caused no effect on VV replication, whereas alternative activation of MDMs by IL-10 or LPS plus IL-1β treatment significantly decreased VV production. The IL-10-mediated suppression of VV replication was largely due to STAT3 activation, as a STAT3 inhibitor restored virus production to levels observed without IL-10 stimulation. In conclusion, our data indicate that PHL subsets express and share VV protein receptors enriched in lipid rafts. We also demonstrate that primary human macrophages are permissive to VV replication. After infection, MDMs produced EEV for long-range dissemination and also form structures associated with virions which may contribute to cell-cell spread.
VIRAL MODULATION OF MHC CLASS II-MEDIATED ANTIGEN PRESENTATION
(2009-06-24T12:57:08Z) Wang, Nan; Blum, Janice Sherry, 1957-; He, Johnny J.; Kaplan, Mark H.; Gallagher, Patricia J.; Harrington, Maureen A.
Vaccinia virus (VV) has been used as a vaccine, yet safety concerns remain due to its viral immunoevasive properties. Among these, VV infection of antigen presentation cells (APC) perturbs MHC class II-mediated antigen (Ag) presentation. The goals of this project include: 1) to define mechanisms by which VV disrupts class II presentation; and 2) to examine whether disruption of the class II pathway by VV alters T cell responses in vitro and in vivo. A significant reduction in the expression of the class II chaperone, invariant chain (Ii), was observed during the late stage of VV infection. Yet surface expression of MHC class II molecules was maintained along with cell viability. To examine whether VV acts solely to disrupt host protein synthesis, B cells were treated with an inhibitor of translation-cycloheximide (CHX). Like VV, CHX negatively regulated Ii protein expression and class II presentation. Ii proteolysis also contributed in part to reduce Ii expression in VV infected and CHX treated APC. Yet only VV infection altered lysosomal protease expression, potentially influencing Ii degradation. Over-expression or ectopic-expression of Ii partially protected cells from VV-induced class II dysfunction. These studies suggest VV destabilizes class II molecules by disrupting Ii expression. To examine the presentation of viral Ags by class II, CD4 T cells from VV-primed mice were used. Viral proteins were presented by class II shortly after APC exposure to low concentrations of VV. The presentation of VV Ags correlated temporally with reductions in exogenous peptide presentation. At higher MOI (≥ 1), class II presentation of VV Ags was reduced. To examine the in vivo effects of VV on Ag presentation, a mouse model of ovalbumin-induced airway hypersensitivity was used. Th2 cytokine production was reduced, while a novel inflammatory cytokine Interleukin-17 (IL-17) production was enhanced in asthmatic VV-infected mice. In health mice, repeated VV infections lead to enhanced CD8 T cell production of Interferon-γ (IFN-γ) and IL-17. Finally, antibodies to a viral protein H3 were generated and shown to preserve class II presentation. Together these studies suggest VV disruption of the class II pathway may blunt T cell responses to VV.
Virus-encoded ectopic CD74 enhances poxvirus vaccine efficacy
(Wiley Blackwell (Blackwell Publishing), 2014-04) Walline, Crystal C.; Deffit, Sarah N.; Wang, Nan; Guindon, Lynette M.; Crotzer, Victoria L.; Liu, Jianyun; Hollister, Kristin; Eisenlohr, Laurence C.; Brutkiewicz, Randy R.; Kaplan, Mark H.; Blum, Janice S.; Department of Microbiology & Immunology, IU School of Medicine
Vaccinia virus (VV) has been used globally as a vaccine to eradicate smallpox. Widespread use of this viral vaccine has been tempered in recent years because of its immuno-evasive properties, with restrictions prohibiting VV inoculation of individuals with immune deficiencies or atopic skin diseases. VV infection is known to perturb several pathways for immune recognition including MHC class II (MHCII) and CD1d-restricted antigen presentation. MHCII and CD1d molecules associate with a conserved intracellular chaperone, CD74, also known as invariant chain. Upon VV infection, cellular CD74 levels are significantly reduced in antigen-presenting cells, consistent with the observed destabilization of MHCII molecules. In the current study, the ability of sustained CD74 expression to overcome VV-induced suppression of antigen presentation was investigated. Viral inhibition of MHCII antigen presentation could be partially ameliorated by ectopic expression of CD74 or by infection of cells with a recombinant VV encoding murine CD74 (mCD74-VV). In contrast, virus-induced disruptions in CD1d-mediated antigen presentation persisted even with sustained CD74 expression. Mice immunized with the recombinant mCD74-VV displayed greater protection during VV challenge and more robust anti-VV antibody responses. Together, these observations suggest that recombinant VV vaccines encoding CD74 may be useful tools to improve CD4⁺ T-cell responses to viral and tumour antigens.

Browsing by Subject "Vaccinia virus"

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