Abstract
Human cytomegalovirus (HCMV), a common opportunistic pathogen of significant clinical importance, targets immunocompromised individuals of the human population worldwide. The absence of a licensed vaccine and the low efficacy of currently available drugs remain a barrier to combating the global infection. The HCMV's ability to modulate and escape innate immune responses remains a critical step in the ongoing search for potential drug targets. Here, we describe the complex interplay between HCMV and the host immune system, focusing on different evasion strategies that the virus has employed to subvert innate immune responses. We especially highlight the mechanisms and role of host antiviral restriction factors and provide insights into viral modulation of pro-inflammatory NF-κB and interferon signaling pathways.
Papers of special note have been highlighted as: • of interest; •• of considerable interest
References
- 1 . Cytomegaloviruses. In: Fields Virology. Knipe DM, Howley PM (Eds). Lippincott Williams & Wilkins, Philadelphia, PA, USA, 2701–2772 (2007).
- 2 Decoding human cytomegalovirus. Science 338(6110), 1088–1093 (2012).
- 3 . The pathogenesis of human cytomegalovirus. J. Pathol. 235(2), 288–297 (2015).
- 4 . Expanding role of cytomegalovirus as a human pathogen. J. Med. Virol. 88(7), 1103–1112 (2016).
- 5 . The “silent” global burden of congenital cytomegalovirus. Clin. Microbiol. Rev. 26(1), 86–102 (2013).
- 6 . Congenital human cytomegalovirus infection and the enigma of maternal immunity. J. Virol. 91(15), e02392–16 (2017).
- 7 . On the demographic and selective forces shaping patterns of human cytomegalovirus variation within hosts. Pathogens 7(1), 16 (2018).
- 8 . Maternal immunity and the natural history of congenital human cytomegalovirus infection. Viruses 10(8), 405 (2018).
- 9 . Hallmarks of human “immunosenescence”: adaptation or dysregulation? Immun. Ageing 9(1), 15 (2012).
- 10 . Mechanisms underlying T cell immunosenescence: aging and cytomegalovirus infection. Front. Microbiol. 7, 2111 (2016).
- 11 Antibodies against human cytomegalovirus in the pathogenesis of systemic sclerosis: a gene array approach. PLoS Med. 3(1), e2 (2006).
- 12 . Human cytomegalovirus and autoimmune disease. Biomed. Res. Int. 2014, 472978 (2014).
- 13 Increased immunoreactivity against human cytomegalovirus UL83 in systemic sclerosis. Clin. Exp. Rheumatol. 106(4), 31–34 (2017).
- 14 A paradigmatic interplay between human cytomegalovirus and host immune system: possible involvement of viral antigen-driven CD8+ T cell responses in systemic sclerosis. Viruses 10(9), 508 (2018).
- 15 . Cytomegalovirus is present in a very high proportion of brains from vascular dementia patients. Neurobiol. Dis. 9(1), 82–87 (2002).
- 16 . Cytomegalovirus infection and coronary heart disease risk: a meta-analysis. Mol. Biol. Rep. 39(6), 6537–6546 (2012).
- 17 . Human cytomegalovirus infection and coronary heart disease: a systematic review. Virol. J. 15(1), 31 (2018).
- 18 . Chronic cytomegalovirus infection and inflammation are associated with prevalent frailty in community-dwelling older women. J. Am. Geriatr. Soc. 53(5), 747–754 (2005).
- 19 . Cytomegalovirus antibody level and mortality among community-dwelling older adults with stable cardiovascular disease. JAMA 301(4), 380–382 (2009).
- 20 . Cytomegalovirus infection in brain tumors. Oncoimmunology 1(5), 739–740 (2012).
- 21 Specific localisation of human cytomegalovirus nucleic acids and proteins in human colorectal cancer. Lancet 360(9345), 1557–1563 (2002).
- 22 . High prevalence of human cytomegalovirus in prostatic intraepithelial neoplasia and prostatic carcinoma. J. Urol. 170(3), 998–1002 (2003).
- 23 . Cytomegalovirus and brain tumor: epidemiology, biology and therapeutic aspects. Curr. Opin. Oncol. 25(6), 682–688 (2013).
- 24 . The human cytomegalovirus, from oncomodulation to oncogenesis. Viruses. 10(8), (2018).
- 25 . New therapies for human cytomegalovirus infections. Antiviral Res. 159, 153–174 (2018).
- 26 . Progress toward development of a vaccine against congenital cytomegalovirus infection. Clin. Vaccine Immunol. 24(12), e00268–17 (2017).
- 27 . Vaccination against the human cytomegalovirus. Vaccine
pii:S0264-410X(18)30288-3 (2018) (Epub ahead of print). - 28 . Antiviral drug resistance of human cytomegalovirus. Clin. Microbiol. Rev. 23(4), 689–712 (2010).
- 29 . Drug susceptibility and replicative capacity of multidrug-resistant recombinant human cytomegalovirus harboring mutations in UL56 and UL54 genes. Antimicrob. Agents Chemother. 61(11), e01044–17 (2017).
- 30 . Rapid in vitro evolution of human cytomegalovirus UL56 mutations that confer letermovir resistance. Antimicrob. Agents Chemother. 59(10), 6588–6593 (2015).
- 31 . The genetic basis of human cytomegalovirus resistance and current trends in antiviral resistance analysis. Infect. Disord. Drug Targets 11(5), 504–513 (2011).
- 32 . Viral evasion of DNA-stimulated innate immune responses. Cell. Mol. Immunol. 14(1), 4–13 (2017).
- 33 Interplay between human cytomegalovirus and intrinsic/innate host responses: a complex bidirectional relationship. Mediators Inflamm. 2012, 607276 (2012).
- 34 . CMV and natural killer cells: shaping the response to vaccination. Eur. J. Immunol. 48(1), 50–65 (2018).
- 35 NKG2D and its ligands: “One for All, All for One.” Front. Immunol. 9, 476 (2018).
- 36 . Attenuation of innate immunity by cytomegalovirus IL-10 establishes a long-term deficit of adaptive antiviral immunity. Proc. Natl Acad. Sci. USA 107(52), 22647–22652 (2010).
- 37 . Tumor and viral recognition by natural killer cells receptors. Semin. Cancer Biol. 16(5), 348–358 (2006).
- 38 . CMV-encoded Fcγ receptors: modulators at the interface of innate and adaptive immunity. Semin. Immunopathol. 36(6), 627–640 (2014).
- 39 . Host cell-derived complement control proteins CD55 and CD59 are incorporated into the virions of two unrelated enveloped viruses. Human T cell leukemia/lymphoma virus type I (HTLV-I) and human cytomegalovirus (HCMV). J. Immunol. 155(9), 4376–4381 (1995).
- 40 . Altered expression of host-encoded complement regulators on human cytomegalovirus-infected cells. Eur. J. Immunol. 26(7), 1532–1538 (1996).
- 41 Human cytomegalovirus downregulates complement receptors (CR3, CR4) and decreases phagocytosis by macrophages. J. Med. Virol. 76(3), 361–366 (2005).
- 42 . Restriction factors: a defense against retroviral infection. Trends Microbiol. 11(6), 286–291 (2003). •• Provides the definition of RFs and their molecular mechanisms for retrovirus replication inhibition.
- 43 . Human immunodeficiency virus, restriction factors, and interferon. J. Interferon Cytokine Res. 29(9), 569–580 (2009).
- 44 . Intrinsic host restrictions to HIV-1 and mechanisms of viral escape. Nat. Immunol. 16(6), 546–553 (2015).
- 45 . Innate immune sensing of HIV-1 infection. Curr. Opin. HIV AIDS 10(2), 96–102 (2015).
- 46 . Recognition of herpesviruses by the innate immune system. Nat. Rev. Immunol. 11(2), 143–154 (2011). •• Describes the main pathways involved in innate immune detection of herpesviruses.
- 47 . Human cytomegalovirus immediate-early gene expression is restricted by the nuclear domain 10 component Sp100. J. Gen. Virol. 92(Pt 7), 1532–1538 (2011).
- 48 . Evidence for a dual antiviral role of the major nuclear domain 10 component Sp100 during the immediate-early and late phases of the human cytomegalovirus replication cycle. J. Virol. 85(18), 9447–9458 (2011).
- 49 . Emerging role of PML nuclear bodies in innate immune signaling. J. Virol. 90(13), 5850–5854 (2016).
- 50 . Herpesvirus tegument and immediate early proteins are pioneers in the battle between viral infection and nuclear domain 10-related host defense. Virus Res. 238, 40–48 (2017).
- 51 . Components of promyelocytic leukemia nuclear bodies (ND10) act cooperatively to repress herpesvirus infection. J. Virol. 87(4), 2174–2185 (2013).
- 52 . Contribution of the major ND10 proteins PML, hDaxx and Sp100 to the regulation of human cytomegalovirus latency and lytic replication in the monocytic cell line THP-1. Viruses 7(6), 2884–2907 (2015).
- 53 . Nuclear domain 10 components upregulated via interferon during human cytomegalovirus infection potently regulate viral infection. J. Gen. Virol. 98(7), 1795–1805 (2017).
- 54 . Modulation of the innate immune response by human cytomegalovirus. Infect. Genet. Evol. 64, 105–114 (2018).
- 55 The intracellular DNA sensor IFI16 gene acts as restriction factor for human cytomegalovirus replication. PLoS Pathog. 8(1), e1002498 (2012).
- 56 . The interferon-inducible DNA-sensor protein IFI16: a key player in the antiviral response. New Microbiol. 38(1), 5–20 (2015).
- 57 . Intrinsic host restriction factors of human cytomegalovirus replication and mechanisms of viral escape. World J. Virol. 5(3), 87–96 (2016).
- 58 Human cytomegalovirus pUL83 stimulates activity of the viral immediate-early promoter through its interaction with the cellular IFI16 protein. J. Virol. 84(15), 7803–7814 (2010).
- 59 Innate nuclear sensor IFI16 translocates into the cytoplasm during the early stage of in vitro human cytomegalovirus infection and is entrapped in the egressing virions during the late stage. J. Virol. 88(12), 6970–6982 (2014).
- 60 Regulatory interaction between the cellular restriction factor IFI16 and viral pp65 (pUL83) modulates viral gene expression and IFI16 protein stability. J. Virol. 90(18), 8238–8250 (2016).
- 61 . Viral DNA sensors IFI16 and cyclic GMP-AMP synthase possess distinct functions in regulating viral gene expression, immune defenses, and apoptotic responses during herpesvirus infection. MBio 7(6), e01553–16 (2016).
- 62 Human cytomegalovirus tegument protein pp65 (pUL83) dampens type I interferon production by inactivating the DNA sensor cGAS without affecting STING. J. Virol. 92(6), e01774–17 (2018).
- 63 . Viperin (cig5), an IFN-inducible antiviral protein directly induced by human cytomegalovirus. Proc. Natl Acad. Sci. USA 98(26), 15125–15130 (2001).
- 64 . Viperin: a multifunctional, interferon-inducible protein that regulates virus replication. Cell Host Microbe 10(6), 534–539 (2011).
- 65 . Human cytomegalovirus directly induces the antiviral protein viperin to enhance infectivity. Science 332(6033), 1093–1097 (2011).
- 66 . Viperin regulates cellular lipid metabolism during human cytomegalovirus infection. PLoS Pathog. 9(8), e1003497 (2013).
- 67 . DNA Editing by APOBECs: a genomic preserver and transformer. Trends Genet. 32(1), 16–28 (2016).
- 68 . Intrinsic cellular defenses against human immunodeficiency viruses. Immunity 37(3), 399–411 (2012).
- 69 . Extensive editing of both hepatitis B virus DNA strands by APOBEC3 cytidine deaminases in vitro and in vivo. Proc. Natl Acad. Sci. USA 102(23), 8321–8326 (2005).
- 70 . Inhibition of hepatitis B virus replication by APOBEC3G. Science 303(5665), 1829 (2004).
- 71 . In vivo examination of mouse APOBEC3- and human APOBEC3A- and APOBEC3G-mediated restriction of parvovirus and herpesvirus infection in mouse models. J. Virol. 90(17), 8005–8012 (2016).
- 72 Deaminase-independent inhibition of parvoviruses by the APOBEC3A cytidine deaminase. PLoS Pathog. 5(5), e1000439 (2009).
- 73 . Evidence for editing of human papillomavirus DNA by APOBEC3 in benign and precancerous lesions. Science 320(5873), 230–233 (2008).
- 74 Characterization of BK polyomaviruses from kidney transplant recipients suggests a role for APOBEC3 in driving in-host virus evolution. Cell Host Microbe 23(5), 628.e7–635.e7 (2018).
- 75 Genetic editing of herpes simplex virus 1 and Epstein-Barr herpesvirus genomes by human APOBEC3 cytidine deaminases in culture and in vivo. J. Virol. 85(15), 7594–7602 (2011).
- 76 APOBEC3A is upregulated by human cytomegalovirus (HCMV) in the maternal-fetal interface, acting as an innate Anti-HCMV effector. J. Virol. 91(23), e01296–17 (2017).
- 77 Evasion strategy of human cytomegalovirus to escape interferon-β-induced APOBEC3G editing activity. J. Virol. 92(19), e01224–18 (2018).
- 78 . Vaccinia virus replication is not affected by APOBEC3 family members. Virol. J. 3, 86 (2006).
- 79 . APOBECs and virus restriction. Virology 479–480, 131–145 (2015). •• Discusses the viral pathogens whose replication is impaired by APOBEC enzymes.
- 80 SPOC1 (PHF13) is required for spermatogonial stem cell differentiation and sustained spermatogenesis. J. Cell. Sci. 124(Pt 18), 3137–3148 (2011).
- 81 SPOC1: a novel PHD-containing protein modulating chromatin structure and mitotic chromosome condensation. J. Cell. Sci. 122(Pt 16), 2946–2956 (2009).
- 82 . Inefficient double-strand break repair in murine rod photoreceptors with inverted heterochromatin organization. Curr. Biol. 24(10), 1080–1090 (2014).
- 83 SPOC1 modulates DNA repair by regulating key determinants of chromatin compaction and DNA damage response. Nucleic Acids Res. 40(22), 11363–11379 (2012).
- 84 PHF13 is a molecular reader and transcriptional co-regulator of H3K4me2/3. Elife 5, e10607 (2016).
- 85 SPOC1-mediated antiviral host cell response is antagonized early in human adenovirus type 5 infection. PLoS Pathog. 9(11), e1003775 (2013).
- 86 Chromatin-remodeling factor SPOC1 acts as a cellular restriction factor against human cytomegalovirus by repressing the major immediate early promoter. J. Virol. 92(14), e00342–18 (2018).
- 87 . Human MxA protein: an interferon-induced dynamin-like GTPase with broad antiviral activity. J. Interferon Cytokine Res. 31(1), 79–87 (2011).
- 88 . Mx GTPases: dynamin-like antiviral machines of innate immunity. Trends Microbiol. 23(3), 154–163 (2015).
- 89 Human MX2 is an interferon-induced post-entry inhibitor of HIV-1 infection. Nature 502(7472), 559–562 (2013).
- 90 The interferon-inducible MxB protein inhibits HIV-1 infection. Cell Host Microbe 14(4), 398–410 (2013).
- 91 MX2 is an interferon-induced inhibitor of HIV-1 infection. Nature 502(7472), 563–566 (2013).
- 92 . Role of MxB in alpha interferon-mediated inhibition of HIV-1 infection. J. Virol. 92(17), e00422–18 (2018).
- 93 . Evolutionary analyses suggest a function of MxB immunity proteins beyond lentivirus restriction. PLoS Pathog. 11(12), e1005304 (2015).
- 94 Human MxB protein is a pan-herpesvirus restriction factor. J. Virol. 92(17), e01056–18 (2018).
- 95 MxB is an interferon-induced restriction factor of human herpesviruses. Nat. Commun. 9(1), 1980 (2018).
- 96 . Interferons and viruses: an evolutionary arms race of molecular interactions. Trends Immunol. 36(3), 124–138 (2015). •• Outlines the knowledge about the interplay and the evolution between interferon pathways and viral infections.
- 97 . Pathogen recognition and inflammatory signaling in innate immune defenses. Clin. Microbiol. Rev. 22(2), 240–273; Table of Contents (2009).
- 98 . Interferon-γ and systemic autoimmunity. Discov. Med. 16(87), 123–131 (2013).
- 99 . Human cytomegalovirus induces the interferon response via the DNA sensor ZBP1. J. Virol. 84(1), 585–598 (2010).
- 100 cGAS senses human cytomegalovirus and induces type I interferon responses in human monocyte-derived cells. PLoS Pathog. 12(4), e1005546 (2016).
- 101 Human cytomegalovirus exploits interferon-induced transmembrane proteins to facilitate morphogenesis of the virion assembly compartment. J. Virol. 89(6), 3049–3061 (2015).
- 102 . IFITMs restrict the replication of multiple pathogenic viruses. J. Mol. Biol. 425(24), 4937–4955 (2013).
- 103 . The antiviral restriction factors IFITM1, 2 and 3 do not inhibit infection of human papillomavirus, cytomegalovirus and adenovirus. PLoS ONE 9(5), e96579 (2014).
- 104 . Major human cytomegalovirus structural protein pp65 (ppUL83) prevents interferon response factor 3 activation in the interferon response. J Virol. 78(20), 10995–11006 (2004).
- 105 . Human cytomegalovirus UL83-coded pp65 virion protein inhibits antiviral gene expression in infected cells. Proc. Natl Acad. Sci. USA 100(20), 11439–11444 (2003).
- 106 . Human cytomegalovirus tegument protein pUL83 inhibits IFI16-mediated DNA sensing for immune evasion. Cell Host Microbe 14(5), 591–599 (2013).
- 107 . Nuclear/cytoplasmic localization of IRFs in response to viral infection or interferon stimulation. J. Interferon Cytokine Res. 22(1), 103–109 (2002).
- 108 Human cytomegalovirus protein UL31 inhibits DNA sensing of cGAS to mediate immune evasion. Cell Host Microbe 24(1), 69.e4–80.e4 (2018).
- 109 Human cytomegalovirus tegument protein UL82 inhibits STING-mediated signaling to evade antiviral immunity. Cell Host Microbe 21(2), 231–243 (2017).
- 110 Human cytomegalovirus-encoded US9 targets MAVS and STING signaling to evade type I interferon immune responses. Nat. Commun. 9(1), 125 (2018).
- 111 . Interferon regulatory factor 3 is necessary for induction of antiviral genes during human cytomegalovirus infection. J. Virol. 80(2), 1032–1037 (2006).
- 112 . Human cytomegalovirus immediate-early 2 gene expression blocks virus-induced beta interferon production. J. Virol. 79(6), 3873–3877 (2005).
- 113 . Human cytomegalovirus immediate-early 2 protein IE86 blocks virus-induced chemokine expression. J. Virol. 80(2), 920–928 (2006).
- 114 . Human cytomegalovirus IE2 86 kDa protein induces STING degradation and inhibits cGAMP-mediated IFN-β induction. Front. Microbiol. 8, 1854 (2017).
- 115 . Mechanisms of type-I- and type-II-interferon-mediated signalling. Nat. Rev. Immunol. 5(5), 375–386 (2005).
- 116 Human cytomegalovirus UL23 inhibits transcription of interferon-γ stimulated genes and blocks antiviral interferon-γ responses by interacting with human N-myc interactor protein. PLoS Pathog. 14(1), e1006867 (2018).
- 117 Consecutive inhibition of ISG15 expression and ISGylation by cytomegalovirus regulators. PLoS Pathog. 12(8), e1005850 (2016).
- 118 . Restriction of human cytomegalovirus replication by ISG15, a host effector regulated by cGAS-STING double-stranded-DNA sensing. J. Virol. 91(9), e02483–16 (2017).
- 119 . The multiple faces of proteinkinase R in antiviral defense. Virulence 4(1), 85–89 (2013).
- 120 Protein kinase R contributes to immunity against specific viruses by regulating interferon mRNA integrity. Cell Host Microbe 7(5), 354–361 (2010).
- 121 . NF-kappaB activation by double-stranded-RNA-activated protein kinase (PKR) is mediated through NF-kappaB-inducing kinase and IkappaB kinase. Mol. Cell. Biol. 20(4), 1278–1290 (2000).
- 122 . Essential role for either TRS1 or IRS1 in human cytomegalovirus replication. J Virol. 83(9), 4112–4120 (2009).
- 123 . Human cytomegalovirus pTRS1 and pIRS1 antagonize protein kinase R to facilitate virus replication. J. Virol. 90(8), 3839–3848 (2016).
- 124 . The human cytomegalovirus UL26 protein antagonizes NF-κB activation. J. Virol. 88(24), 14289–14300 (2014).
- 125 Deletion of open reading frame UL26 from the human cytomegalovirus genome results in reduced viral growth, which involves impaired stability of viral particles. J. Virol. 80(11), 5423–5434 (2006).
- 126 . UL26-deficient human cytomegalovirus produces virions with hypophosphorylated pp28 tegument protein that is unstable within newly infected cells. J. Virol. 80(7), 3541–3548 (2006).
- 127 . Human cytomegalovirus gene UL76 induces IL-8 expression through activation of the DNA damage response. PLoS Pathog. 9(9), e1003609 (2013).
- 128 . Functional map of human cytomegalovirus AD169 defined by global mutational analysis. Proc. Natl Acad. Sci. USA 100(21), 12396–12401 (2003).
- 129 . RNAs are packaged into human cytomegalovirus virions in proportion to their intracellular concentration. J. Virol. 78(19), 10390–10398 (2004).
- 130 Identification of proteins in human cytomegalovirus (HCMV) particles: the HCMV proteome. J. Virol. 78(20), 10960–10966 (2004).
- 131 . The human cytomegalovirus virion possesses an activated casein kinase II that allows for the rapid phosphorylation of the inhibitor of NF-κB, IκBα. J. Virol. 81(10), 5305–5314 (2007).
- 132 . Modulation of the NFκb signalling pathway by human cytomegalovirus. Virology 1(1), 104 (2017).
- 133 Cutting edge: a novel viral TNF receptor superfamily member in virulent strains of human cytomegalovirus. J. Immunol. 162(12), 6967–6970 (1999).
- 134 . The UL144 gene product of human cytomegalovirus activates NFkappaB via a TRAF6-dependent mechanism. EMBO J. 25(18), 4390–4399 (2006).
- 135 . An activation-defective mutant of the human cytomegalovirus IE2p86 protein inhibits NF-kappaB-mediated stimulation of the human interleukin-6 promoter. J. Gen. Virol. 88(Pt 9), 2435–2440 (2007).
- 136 NF-κB-mediated activation of the chemokine CCL22 by the product of the human cytomegalovirus gene UL144 escapes regulation by viral IE86. J. Virol. 82(9), 4250–4256 (2008).
- 137 . Who's Driving? Human cytomegalovirus, interferon, and NFκB signaling. Viruses 10(9), 447 (2018).
- 138 . Human cytomegalovirus harbors its own unique IL-10 homolog (cmvIL-10). Proc. Natl Acad. Sci. USA 97(4), 1695–1700 (2000).
- 139 . Crystal structure of human cytomegalovirus IL-10 bound to soluble human IL-10R1. Proc. Natl Acad. Sci. USA 99(14), 9404–9409 (2002).
- 140 . HCMV IL-10 suppresses cytokine expression in monocytes through inhibition of nuclear factor-kappaB. Viral Immunol. 21(4), 477–482 (2008).
- 141 . Latency and reactivation of human cytomegalovirus. J. Gen. Virol. 87(Pt 7), 1763–1779 (2006).
- 142 . The human cytomegalovirus-encoded receptor US28 increases the activity of the major immediate-early promoter/enhancer. Virus Res. 118(1–2), 196–200 (2006).
- 143 . Human cytomegalovirus chemokine receptor gene US28 is transcribed in latently infected THP-1 monocytes. J. Virol. 75(13), 5949–5957 (2001).
- 144 . Transcriptome-wide characterization of human cytomegalovirus in natural infection and experimental latency. Proc. Natl Acad. Sci. USA 114(49), E10586–E10595 (2017).
- 145 Defining the transcriptional landscape during cytomegalovirus latency with single-cell RNA sequencing. mBio 9(2), e00013–e00018 (2018).
- 146 Constitutive signaling of the human cytomegalovirus-encoded chemokine receptor US28. J. Biol. Chem. 276(2), 1133–1137 (2001).
- 147 . Latency-associated expression of human cytomegalovirus US28 attenuates cell signaling pathways to maintain latent infection. mBio 8(6), e01754–17 (2017).
- 148 Latency-associated degradation of the MRP1 drug transporter during latent human cytomegalovirus infection. Science 340(6129), 199–202 (2013).
- 149 Long and short isoforms of the human cytomegalovirus UL138 protein silence IE transcription and promote latency. J. Virol. 90(20), 9483–9494 (2016).
- 150 . The Role of HCMV and HIV-1 microRNAs: processing, and mechanisms of action during viral infection. Front. Microbiol. 8, 689 (2017).
- 151 . Human cytomegalovirus encoded microRNAs: hitting targets. Expert Rev. Anti Infect. Ther. 13(12), 1469–1479 (2015).
- 152 . Cytomegalovirus microRNAs. Curr. Opin. Virol. 7, 40–46 (2014).
- 153 The expression of human cytomegalovirus microRNA MiR-UL148D during latent infection in primary myeloid cells inhibits activin A-triggered secretion of IL-6. Sci. Rep. 6, 31205 (2016).