Guinea pig cytomegalovirus GP129/131/133, homologues of human cytomegalovirus UL128/130/131A, are necessary for infection of monocytes and macrophages

The GP129, GP131 and GP133 genes of guinea pig cytomegalovirus (GPCMV) are homologues of human cytomegalovirus UL128, UL130 and UL131A, respectively, which are essential for infection of endothelial and epithelial cells, and for viral transmission to leukocytes. Our previous study demonstrated that a GPCMV strain lacking the 1.6 kb locus that contains the GP129, GP131 and GP133 genes had a growth defect in animals. Here, we demonstrated that the WT strain, but not the 1.6 kb-deleted strain, formed capsids in macrophages prepared from the peritoneal fluid. To understand the mechanism, we prepared GPCMV strains defective in each of GP129, GP131 and GP133, and found that they were all essential for the infection of peritoneal, splenic and PBMC-derived macrophages/monocytes, and for expression of immediate-early antigens in the macrophages/monocytes, although they were dispensable for infection of fibroblasts. Monocyte/macrophage tropism could be one of the important determinants for viral dissemination in vivo.

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Roles of GP33, a guinea pig cytomegalovirus-encoded G protein-coupled receptor homolog, in cellular signaling, viral growth and inflammation in vitro and in vivo

PLoS Pathogens ◽

10.1371/journal.ppat.1007487 ◽

2018 ◽

Vol 14 (12) ◽

pp. e1007487 ◽

Cited By ~ 2

Author(s):

Miei Takeda ◽

Shinji Watanabe ◽

Harutaka Katano ◽

Kazuma Noguchi ◽

Yuko Sato ◽

...

Keyword(s):

Guinea Pig ◽

G Protein ◽

Cellular Signaling ◽

G Protein Coupled Receptor ◽

Viral Growth ◽

Guinea Pig Cytomegalovirus ◽

G Protein Coupled

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Human Cytomegalovirus Genes in the 15-Kilobase Region Are Required for Viral Replication in Implanted Human Tissues in SCID Mice

Journal of Virology ◽

10.1128/jvi.79.4.2115-2123.2005 ◽

2005 ◽

Vol 79 (4) ◽

pp. 2115-2123 ◽

Cited By ~ 26

Author(s):

Weijia Wang ◽

Shannon L. Taylor ◽

Stacey A. Leisenfelder ◽

Robert Morton ◽

Jennifer F. Moffat ◽

...

Keyword(s):

Human Cytomegalovirus ◽

Severe Combined Immunodeficiency ◽

Artificial Chromosome ◽

Scid Mice ◽

Open Reading Frames ◽

Growth Defect ◽

Human Tissues ◽

Human Thymus ◽

Hcmv Replication

ABSTRACT Since animal models for studying human cytomegalovirus (HCMV) replication in vivo and pathogenesis are not available, severe combined immunodeficiency mice into which human tissues were implanted (SCID-hu mice) provide an alternative and valuable model for such studies. The HCMV clinical isolates, including those of the Toledo strain, replicate to high titers in human tissue implanted into SCID mice; however, the attenuated AD169 strain has completely lost this ability. The major difference between Toledo and AD169 is a 15-kb segment, encoding 19 open reading frames, which is present in all virulent strains but deleted from attenuated strains. This fact suggests that crucial genes required for HCMV replication in vivo are localized to this region. In this study, the importance of this 15-kb segment for HCMV replication in vivo was determined. First, ToledoBAC virus (produced from a Toledo bacterial artificial chromosome) and AD169 virus were tested for growth in SCID-hu mice. ToledoBAC, like Toledo, grew to high titers in implanted human thymus and liver tissues, while AD169 did not. This outcome showed that the Toledo genome propagated in bacteria (ToledoBAC) retained its virulence. The 15-kb segment was then deleted from ToledoBAC, and the resulting virus, ToledoΔ15kb, was tested for growth in both human foreskin fibroblast (HFF) cells and SCID-hu mice. ToledoΔ15kb had a minor growth defect in HFF but completely failed to replicate in human thymus and liver implants. This failure to grow was rescued when the 15-kb region was inserted back into the ToledoΔ15kb genome. These results directly demonstrated that the genes located in the 15-kb segment are crucial for HCMV replication in vivo.

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Molecular, Biological, and In Vivo Characterization of the Guinea Pig Cytomegalovirus (CMV) Homologs of the Human CMV Matrix Proteins pp71 (UL82) and pp65 (UL83)

Journal of Virology ◽

10.1128/jvi.78.18.9872-9889.2004 ◽

2004 ◽

Vol 78 (18) ◽

pp. 9872-9889 ◽

Cited By ~ 24

Author(s):

Alistair McGregor ◽

Fenyong Liu ◽

Mark R. Schleiss

Keyword(s):

Guinea Pig ◽

Guinea Pigs ◽

Matrix Proteins ◽

Wild Type ◽

Viral Dna ◽

Guinea Pig Cytomegalovirus ◽

Human Cmv ◽

Hsv 1

ABSTRACT We recently identified the genes encoding the guinea pig cytomegalovirus (GPCMV) homologs of the upper and lower matrix proteins of human CMV, pp71 (UL82) and pp65 (UL83), which we designated GP82 and GP83, respectively. Transient-expression studies with a GP82 plasmid demonstrated that the encoded protein targets the nucleus and that the infectivity and plaquing efficiency of cotransfected GPCMV viral DNA was enhanced by GP82. The transactivation function of GP82 was not limited to GPCMV, but was also observed for a heterologous virus, herpes simplex virus type 1 (HSV-1). This was confirmed by its ability to complement the growth of an HSV-1 VP16 transactivation-defective mutant virus in an HSV viral DNA cotransfection assay. Study of a GP82 “knockout” virus (and its attendant rescuant), generated on a GPCMV bacterial artificial chromosome construct, confirmed the essential nature of the gene. Conventional homologous recombination was used to generate a GP83 mutant to examine the role of GP83 in the viral life cycle. Comparison of the one-step growth kinetics of the GP83 mutant (vAM409) and wild-type GPCMV indicated that GP83 protein is not required for viral replication in tissue culture. The role of GP83 in vivo was examined by comparing the pathogenesis of wild-type GPCMV, vAM409, and a control virus, vAM403, in guinea pigs. The vAM409 mutant was significantly attenuated for dissemination in immunocompromised strain 2 guinea pigs, suggesting that the GP83 protein is essential for full pathogenicity in vivo.

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Characterization of the guinea pig cytomegalovirus genome locus that encodes homologs of human cytomegalovirus major immediate-early genes, UL128, and UL130

Virology ◽

10.1016/j.virol.2009.05.034 ◽

2009 ◽

Vol 391 (1) ◽

pp. 99-106 ◽

Cited By ~ 38

Author(s):

Souichi Yamada ◽

Naoki Nozawa ◽

Harutaka Katano ◽

Yoshiko Fukui ◽

Mihoko Tsuda ◽

...

Keyword(s):

Guinea Pig ◽

Human Cytomegalovirus ◽

Immediate Early Genes ◽

Immediate Early ◽

Early Genes ◽

Guinea Pig Cytomegalovirus

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Antiviral effect of oxetanocin G against guinea pig cytomegalovirus infection in vitro and in vivo.

The Journal of Antibiotics ◽

10.7164/antibiotics.43.1573 ◽

1990 ◽

Vol 43 (12) ◽

pp. 1573-1578 ◽

Cited By ~ 7

Author(s):

NAOHIKO YAMAMOTO ◽

YOSHINARI YAMADA ◽

TOHRU DAIKOKU ◽

YUKIHIRO NISHIYAMA ◽

YOSHIHIRO TSUTSUI ◽

...

Keyword(s):

Guinea Pig ◽

Cytomegalovirus Infection ◽

Antiviral Effect ◽

Guinea Pig Cytomegalovirus

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The Human Cytomegalovirus Chemokine vCXCL-1 Modulates Normal Dissemination Kinetics of Murine CytomegalovirusIn Vivo

mBio ◽

10.1128/mbio.01289-19 ◽

2019 ◽

Vol 10 (3) ◽

Cited By ~ 4

Author(s):

Joseph W. Jackson ◽

Trevor J. Hancock ◽

Ellen LaPrade ◽

Pranay Dogra ◽

Eric R. Gann ◽

...

Keyword(s):

Human Cytomegalovirus ◽

Hcmv Infection ◽

Host Immune System ◽

Mcmv Infection ◽

Term Survival ◽

Viral Dissemination ◽

Immunocompromised Mice ◽

Kinetics Of

ABSTRACTHuman cytomegalovirus (HCMV) is a betaherpesvirus that is a significant pathogen within newborn and immunocompromised populations. Morbidity associated with HCMV infection is the consequence of viral dissemination. HCMV has evolved to manipulate the host immune system to enhance viral dissemination and ensure long-term survival within the host. The immunomodulatory protein vCXCL-1, a viral chemokine functioning primarily through the CXCR2 chemokine receptor, is hypothesized to attract CXCR2+neutrophils to infection sites, aiding viral dissemination. Neutrophils harbor HCMVin vivo; however, the interaction between vCXCL-1 and the neutrophil has not been evaluatedin vivo. Using the mouse model and mouse cytomegalovirus (MCMV) infection, we show that murine neutrophils harbor and transfer infectious MCMV and that virus replication initiates within this cell type. Utilizing recombinant MCMVs expressing vCXCL-1 from the HCMV strain (Toledo), we demonstrated that vCXCL-1 significantly enhances MCMV dissemination kinetics. Through cellular depletion experiments, we observe that neutrophils impact dissemination but that overall dissemination is largely neutrophil independent. This work adds neutrophils to the list of innate cells (i.e., dendritic and macrophages/monocytes) that contribute to MCMV dissemination but refutes the hypothesis that neutrophils are the primary cell responding to vCXCL-1.IMPORTANCEAn adequatein vivoanalysis of HCMV’s viral chemokine vCXCL-1 has been lacking. Here we generate recombinant MCMVs expressing vCXCL-1 to study vCXCL-1 functionin vivousing MCMV as a surrogate. We demonstrate that vCXCL-1 increases MCMV dissemination kinetics for both primary and secondary dissemination. Additionally, we provide evidence, that the murine neutrophil is largely a bystander in the mouse’s response to vCXCL-1. We confirm the hypothesis that vCXCL-1 is a HCMV virulence factor. Infection of severely immunocompromised mice with MCMVs expressing vCXCL-1 was lethal in more than 50% of infected animals, while all animals infected with parental virus survived during a 12-day period. This work provides needed insights into vCXCL-1 functionin vivo.

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Human Cytomegalovirus Promotes Survival of Infected Monocytes via a Distinct Temporal Regulation of Cellular Bcl-2 Family Proteins

Journal of Virology ◽

10.1128/jvi.01994-15 ◽

2015 ◽

Vol 90 (5) ◽

pp. 2356-2371 ◽

Cited By ~ 22

Author(s):

Donna Collins-McMillen ◽

Jung Heon Kim ◽

Maciej T. Nogalski ◽

Emily V. Stevenson ◽

Gary C. Chan ◽

...

Keyword(s):

Human Cytomegalovirus ◽

Survival Strategy ◽

Blood Monocytes ◽

Viral Dissemination ◽

Hematogenous Dissemination ◽

Viral Spread ◽

Organ Systems ◽

Viral Survival

ABSTRACTMonocytes play a key role in the hematogenous dissemination of human cytomegalovirus (HCMV) to target organ systems. To infect monocytes and reprogram them to deliver infectious virus, HCMV must overcome biological obstacles, including the short life span of monocytes and their antiviral proapoptotic response to infection. We have shown that virally induced upregulation of cellular Mcl-1 promotes early survival of HCMV-infected monocytes, allowing cells to overcome an early apoptotic checkpoint at around 48 h postinfection (hpi). Here, we demonstrate an HCMV-dependent shift from Mcl-1 as the primary antiapoptotic player to the related protein, Bcl-2, later during infection. Bcl-2 was upregulated in HCMV-infected monocytes beginning at 48 hpi. Treatment with the Bcl-2 antagonist ABT-199 only reduced the prosurvival effects of HCMV in target monocytes beginning at 48 hpi, suggesting that Mcl-1 controls survival prior to 48 hpi, while Bcl-2 promotes survival after 48 hpi. Although Bcl-2 was upregulated following viral binding/signaling through cellular integrins (compared to Mcl-1, which is upregulated through binding/activation of epidermal growth factor receptor [EGFR]), it functioned similarly to Mcl-1, adopting the early role of Mcl-1 in preventing caspase-3 cleavage/activation. This distinct, HCMV-induced shift from Mcl-1 to Bcl-2 occurs in response to a cellular upregulation of proapoptotic Bax, as small interfering RNA (siRNA)-mediated knockdown of Bax reduced the upregulation of Bcl-2 in infected monocytes and rescued the cells from the apoptotic effects of Bcl-2 inhibition. Our data demonstrate a distinct survival strategy whereby HCMV induces a biphasic regulation of cellular Bcl-2 proteins to promote host cell survival, leading to viral dissemination and the establishment of persistent HCMV infection.IMPORTANCEHematogenous dissemination of HCMV via infected monocytes is a crucial component of the viral survival strategy and is required for the establishment of persistent infection and for viral spread to additional hosts. Our system of infected primary human blood monocytes provides us with an opportunity to answer specific questions about viral spread and persistence inin vivo-relevant myeloid cells that cannot be addressed with the more traditionally used replication-permissive cells. Our goal in examining the mechanisms whereby HCMV reprograms infected monocytes to promote viral dissemination is to uncover new targets for therapeutic intervention that would disrupt key viral survival and persistence strategies. Because of this important role in maintaining survival of HCMV-infected monocytes, our new data on the role of Bcl-2 regulation during viral infection represents a promising molecular target for mitigating viral spread and persistence.

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