scholarly journals Host-Adapted Gene Families Involved in Murine Cytomegalovirus Immune Evasion

Viruses ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 128
Author(s):  
Sara Becker ◽  
Annette Fink ◽  
Jürgen Podlech ◽  
Matthias J. Reddehase ◽  
Niels A. Lemmermann

Cytomegaloviruses (CMVs) are host species-specific and have adapted to their respective mammalian hosts during co-evolution. Host-adaptation is reflected by “private genes” that have specialized in mediating virus-host interplay and have no sequence homologs in other CMV species, although biological convergence has led to analogous protein functions. They are mostly organized in gene families evolved by gene duplications and subsequent mutations. The host immune response to infection, both the innate and the adaptive immune response, is a driver of viral evolution, resulting in the acquisition of viral immune evasion proteins encoded by private gene families. As the analysis of the medically relevant human cytomegalovirus by clinical investigation in the infected human host cannot make use of designed virus and host mutagenesis, the mouse model based on murine cytomegalovirus (mCMV) has become a versatile animal model to study basic principles of in vivo virus-host interplay. Focusing on the immune evasion of the adaptive immune response by CD8+ T cells, we review here what is known about proteins of two private gene families of mCMV, the m02 and the m145 families, specifically the role of m04, m06, and m152 in viral antigen presentation during acute and latent infection.

Author(s):  
Mathias Hochgerner ◽  
Eva M Sturm ◽  
Diana Schnoegl ◽  
Grazyna Kwapiszewska ◽  
Horst Olschewski ◽  
...  

2020 ◽  
Vol 8 (1) ◽  
pp. e000337 ◽  
Author(s):  
Lorenzo Galluzzi ◽  
Ilio Vitale ◽  
Sarah Warren ◽  
Sandy Adjemian ◽  
Patrizia Agostinis ◽  
...  

Cells succumbing to stress via regulated cell death (RCD) can initiate an adaptive immune response associated with immunological memory, provided they display sufficient antigenicity and adjuvanticity. Moreover, multiple intracellular and microenvironmental features determine the propensity of RCD to drive adaptive immunity. Here, we provide an updated operational definition of immunogenic cell death (ICD), discuss the key factors that dictate the ability of dying cells to drive an adaptive immune response, summarize experimental assays that are currently available for the assessment of ICD in vitro and in vivo, and formulate guidelines for their interpretation.


2011 ◽  
Vol 79 (10) ◽  
pp. 3940-3946 ◽  
Author(s):  
Cuixia Shi ◽  
Bikash Sahay ◽  
Jennifer Q. Russell ◽  
Karen A. Fortner ◽  
Nicholas Hardin ◽  
...  

ABSTRACTLittle is known regarding the function of γδ T cells, although they accumulate at sites of inflammation in infections and autoimmune disorders. We previously observed that γδ T cellsin vitroare activated byBorrelia burgdorferiin a TLR2-dependent manner. We now observe that the activated γδ T cells can in turn stimulate dendritic cellsin vitroto produce cytokines and chemokines that are important for the adaptive immune response. This suggested thatin vivoγδ T cells may assist in activating the adaptive immune response. We examined this possibilityin vivoand observed that γδ T cells are activated and expand in number duringBorreliainfection, and this was reduced in the absence of TLR2. Furthermore, in the absence of γδ T cells, there was a significantly blunted response of adaptive immunity, as reflected in reduced expansion of T and B cells and reduced serum levels of anti-Borreliaantibodies, cytokines, and chemokines. This paralleled a greaterBorreliaburden in γδ-deficient mice as well as more cardiac inflammation. These findings are consistent with a model of γδ T cells functioning to promote the adaptive immune response during infection.


2010 ◽  
Vol 7 (48) ◽  
pp. 1049-1059 ◽  
Author(s):  
John F. Markham ◽  
Cameron J. Wellard ◽  
Edwin D. Hawkins ◽  
Ken R. Duffy ◽  
Philip D. Hodgkin

During the adaptive immune response, lymphocyte populations undergo a characteristic three-phase process: expansion through a series of cell divisions; cessation of expansion; and, finally, most of the accumulated lymphocytes die by apoptosis. The data used, thus far, to inform understanding of these processes, both in vitro and in vivo , are taken from flow cytometry experiments. One significant drawback of flow cytometry is that individual cells cannot be tracked, so that it is not possible to investigate interdependencies in the fate of cells within a family tree. This deficit in experimental information has recently been overcome by Hawkins et al . (Hawkins et al . 2009 Proc. Natl Acad. Sci. USA 106 , 13 457–13 462 ( doi:10.1073/pnas.0905629106 )), who reported on time-lapse microscopy experiments in which B-cells were stimulated through the TLR-9 receptor. Cells stimulated in this way do not aggregate, so that data regarding family trees can be recorded. In this article, we further investigate the Hawkins et al . data. Our conclusions are striking: in order to explain the familial correlation structure in division times, death times and propensity to divide, a minimum of two distinct heritable factors are necessary. As the data show that two distinct factors are necessary, we develop a stochastic model that has two heritable factors and demonstrate that it can reproduce the key features of the data. This model shows that two heritable factors are sufficient. These deductions have a clear impact upon biological understanding of the adaptive immune response. They also necessitate changes to the fundamental premises behind the tools developed by statisticians to draw deductions from flow cytometry data. Finally, they affect the mathematical modelling paradigms that are used to study these systems, as these are widely developed based on assumptions of cellular independence that are not accurate.


2020 ◽  
Author(s):  
Bo Zhu ◽  
Zhengyu Wang ◽  
Licheng Yao ◽  
Xingyu Lin ◽  
Jie Zhang ◽  
...  

Abstract Recent development of some new immune checkpoint inhibitors has been particularly successfully in melanoma, but the majority of melanoma patients exhibit resistance. Understanding and targeting the potential underlying mechanism/targets, especially the tumor-intrinsic modulators to convert resistant melanomas to immunotherapy sensitivity will potentially provide a significant improvement in patient outcome. Here, Mi-2β, a chromatin remodeling enzyme was identified as a key melanoma-intrinsic effector regulating the adaptive anti-tumor immune response. Loss of Mi-2β rescued the immune response to immunotherapy in vivo. Mechanistically, targeting Mi-2β induced the adaptive immune response by transcriptionally enhancing expression of a set of IFN-γ-responsive genes including CXCL9, CXCL10 and IRF1. Finally, we developed a Mi-2β-targeted inhibitor Z36-MP5, which specifically and effectively induced a response to immune checkpoint blockades in otherwise resistant melanomas. Our work provides a new insight into the epigenetic regulation in adaptive immune response, and highlights a viable strategy to improve immunotherapies in melanoma.


2021 ◽  
Vol 12 ◽  
Author(s):  
Jesús Hernández ◽  
Yanli Li ◽  
Enric Mateu

Dendritic cells (DCs) are the most potent antigen-presenting cells, unique to initiate and coordinate the adaptive immune response. In pigs, conventional DCs (cDCs), plasmacytoid DCs (pDCs), and monocyte-derived DCs (moDCs) have been described in blood and tissues. Different pathogens, such as viruses, could infect these cells, and in some cases, compromise their response. The understanding of the interaction between DCs and viruses is critical to comprehend viral immunopathological responses. Porcine reproductive and respiratory syndrome virus (PRRSV) is the most important respiratory pathogen in the global pig population. Different reports support the notion that PRRSV modulates pig immune response in addition to their genetic and antigenic variability. The interaction of PRRSV with DCs is a mostly unexplored area with conflicting results and lots of uncertainties. Among the scarce certainties, cDCs and pDCs are refractory to PRRSV infection in contrast to moDCs. Additionally, response of DCs to PRRSV can be different depending on the type of DCs and maybe is related to the virulence of the viral isolate. The precise impact of this virus-DC interaction upon the development of the specific immune response is not fully elucidated. The present review briefly summarizes and discusses the previous studies on the interaction of in vitro derived bone marrow (bm)- and moDCs, and in vivo isolated cDCs, pDCs, and moDCs with PRRSV1 and 2.


eLife ◽  
2016 ◽  
Vol 5 ◽  
Author(s):  
Franziska Fuhrmann ◽  
Timo Lischke ◽  
Fridolin Gross ◽  
Tobias Scheel ◽  
Laura Bauer ◽  
...  

The IL-2/IL-2Ralpha (CD25) axis is of central importance for the interplay of effector and regulatory T cells. Nevertheless, the question how different antigen loads are translated into appropriate IL-2 production to ensure adequate responses against pathogens remains largely unexplored. Here we find that at single cell level, IL-2 is binary (digital) and CD25 is graded expressed whereas at population level both parameters show graded expression correlating with the antigen amount. Combining in vivo data with a mathematical model we demonstrate that only this binary IL-2 expression ensures a wide linear antigen response range for Teff and Treg cells under real spatiotemporal conditions. Furthermore, at low antigen concentrations binary IL-2 expression safeguards by its spatial distribution selective STAT5 activation only of closely adjacent Treg cells regardless of their antigen specificity. These data show that the mode of IL-2 secretion is critical to tailor the adaptive immune response to the antigen amount.


2020 ◽  
Author(s):  
Donald R. Griffin ◽  
Maani M. Archang ◽  
Chen H. Kuan ◽  
Westbrook M. Weaver ◽  
Jason S. Weinstein ◽  
...  

AbstractBiomaterial scaffolds represent a promising approach for material-based tissue regeneration. We previously developed microporous annealed particle (MAP) hydrogels - a flowable, microparticle-based hydrogel in which neighboring hydrogel particles are linked in situ to form a porous scaffold that accelerates wound healing. To promote more extensive tissue ingrowth before scaffold degradation, we aimed to slow scaffold degradation by switching the chirality of the crosslinking peptides from L-peptides to D-peptides. Unexpectedly, despite showing the predicted slower enzymatic degradation in vitro, D-peptide crosslinked MAP hydrogel (D-MAP) hastened material degradation in vivo and imparted significant tissue regeneration to healed cutaneous wounds, including increased tensile strength and hair neogenesis. By themselves, D-chiral peptides were poor activators of macrophage innate immune signaling in vivo, but MAP particles elicit IL-33 type 2 myeloid cell recruitment which is amplified in vivo in the presence of D-peptides. Remarkably, D-MAP elicited significant antigen-specific immunity against the D-chiral peptides, and an intact adaptive immune system was required for the hydrogel-induced skin regeneration. These findings demonstrate that the generation of an adaptive immune response from a biomaterial is sufficient to induce cutaneous regenerative healing despite faster scaffold degradation.


2020 ◽  
Author(s):  
Sajad Ahmad Wani ◽  
Manas Ranjan Praharaj ◽  
Amit R Sahu ◽  
Raja Ishaq Nabi Khan ◽  
Kaushal Kishor Rajak ◽  
...  

AbstractImmune response is a highly coordinated cascade involving all the subsets of PBMCs. In this study, RNA-Seq analysis of PBMC subsets - CD4+, CD8+, CD14+, CD21+ and CD335+ cells from day 0 and day 5 of Sungri/96 Peste des Petits Ruminants vaccinated sheep and goats was done to delineate the systems biology behind immune - protection of the vaccine in sheep and goats. Assessment of the immune response processes enriched by the differentially expressed genes in all the subsets suggested a strong dysregulation towards development of early inflammatory microenvironment, which is very much required for differentiation of monocytes to macrophages, and for activation and migration of dendritic cells into the draining lymph nodes. The protein - protein interaction networks among the antiviral molecules (IFIT3, ISG15, MX1, MX2, RSAD2, ISG20, IFIT5 and IFIT1) and common DEGs across PBMCs subsets in both the species identified ISG15 to be an ubiquitous hub, that helps in orchestrating antiviral host response against PPRV. IRF7 was found to be the key master regulator activated in most of the subsets in sheep and goats. Most of the pathways were found to be inactivated in B - lymphocytes of both the species indicating that 5 dpv is too early a time point for the B - lymphocytes to react. The cell mediated immune response and humoral immune response pathways were found more enriched in goats than in sheep. Though, animals from both the species survived the challenge, a contrast in pathway activation was observed in CD335+ cells.ImportancePeste des petits ruminants (PPR) by PPRV is an OIE listed acute, contagious transboundary viral disease of small ruminants. Attenuated Sungri/96 PPRV vaccine used all over India against this PPR, provides long-lasting robust innate and adaptive immune response. The early antiviral response was found mediated through type I interferon independent ISGs expression. However, systems biology behind this immune response is unknown. In this study, in vivo transcriptome profiling of PBMC subsets (CD4+, CD8+, CD14+, CD21+ and CD335+) in vaccinated goats and sheep (at 5 days of post vaccination) was done to understand this systems biology. Though there are a few differences in the systems biology across cells (specially the NK cells) between sheep and goats, the co-ordinated response that is inclusive of all the cell subsets was found to be towards induction of strong innate immune response, which is needed for an appropriate adaptive immune response.


2018 ◽  
Vol 92 (16) ◽  
Author(s):  
James M. Burke ◽  
Clovis R. Bass ◽  
Rodney P. Kincaid ◽  
Emin T. Ulug ◽  
Christopher S. Sullivan

ABSTRACTPolyomaviruses (PyVs) can cause serious disease in immunosuppressed hosts. Several pathogenic PyVs encode microRNAs (miRNAs), small RNAs that regulate gene expression via RNA silencing. Despite recent advances in understanding the activities of PyV miRNAs, the biological functions of PyV miRNAs duringin vivoinfections are mostly unknown. The studies presented here used murine polyomavirus (MuPyV) as a model to assess the roles of the PyV miRNAs in a natural host. This analysis revealed that a MuPyV mutant that is unable to express miRNAs has enhanced viral DNA loads in select tissues at late times after infection. This is consistent with the PyV miRNAs functioning to reduce viral replication during the persistent phase of infection in a natural host. Additionally, the MuPyV miRNA locus promotes viruria during the acute phase of infection as evidenced by a defect in shedding during infection with the miRNA mutant virus. The viruria defect of the miRNA mutant virus could be rescued by infectingRag2−/−mice. These findings implicate the miRNA locus as functioning in both the persistent and acute phases of infection and suggest a role for MuPyV miRNA in evading the adaptive immune response.IMPORTANCEMicroRNAs are expressed by diverse viruses, but for only a few is there any understanding of theirin vivofunction. PyVs can cause serious disease in immunocompromised hosts. Therefore, increased knowledge of how these viruses interact with the immune response is of clinical relevance. Here we show a novel activity for a viral miRNA locus in promoting virus shedding. This work indicates that in addition to any role for the PyV miRNA locus in long-term persistence, it also has biological activity during the acute phase. As this mutant phenotype is alleviated by infection of mice lacking an adaptive immune response, our work also connects thein vivoactivity of the PyV miRNA locus to the immune response. Given that PyV-associated disease is associated with alterations in the immune response, our findings help to better understand how the balance between PyVs and the immune response becomes altered in pathogenic states.


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