scholarly journals The attenuated Towne strain of human cytomegalovirus may revert to both endothelial cell tropism and leuko- (neutrophil- and monocyte-) tropism in vitro

2002 ◽  
Vol 83 (8) ◽  
pp. 1993-2000 ◽  
Author(s):  
Giuseppe Gerna ◽  
Elena Percivalle ◽  
Antonella Sarasini ◽  
Fausto Baldanti ◽  
M. Grazia Revello
Keyword(s):  
Endothelial Cell ◽  
Cell Cultures ◽  
Human Cytomegalovirus ◽  
Biological Properties ◽  
Clinical Isolates ◽  
Viral Gene ◽  
Cell Tropism ◽  
Human Embryonic Lung ◽  
Healthy Human

The Towne strain of human cytomegalovirus (HCMV), originally recovered from the urine of a congenitally infected newborn, was attenuated through 125 passages in human embryonic lung fibroblast cell cultures. Although reliable markers of attenuation were not identified, the virus was shown to be attenuated by inoculation of both healthy human volunteers and immunocompromised patients. More recently, Towne (like other laboratory-adapted strains) was shown not to have two biological properties typical of recent clinical isolates: endothelial cell tropism and polymorphonuclear leukocyte tropism. These markers of attenuation are lost by all clinical isolates on extensive propagation in cell cultures and are apparently associated with one another. Here, we show that Towne may reacquire both endothelial cell tropism and leuko- (polymorphonuclear- and monocyte-) tropism on adaptation to growth in endothelial cell cultures. However, reversion to endothelial cell tropism is dissociated from reversion to leukotropism, since the latter was reacquired 10–20 passages later. Thus, these two biological properties, which were considered to be encoded by the same viral gene(s), appear to be distinct. Both restriction fragment length polymorphism and Southern blot analysis demonstrated the identity of the attenuated and endothelial cell tropic variants of Towne, thus suggesting that only minor variations (mutations) of the viral genome may be responsible for loss or reacquisition of the two biological properties. Viral genes involved in endothelial cell tropism and leukotropism remain to be identified. However, reversion of attenuated strains to pathogenicity in vivo cannot be excluded a priori.

scholarly journals Human Cytomegalovirus Cell Tropism and Host Cell Receptors

Vaccines ◽  
2019 ◽  
Vol 7 (3) ◽  
pp. 70 ◽  
Author(s):  
Gerna ◽  
Kabanova ◽  
Lilleri
Keyword(s):  
Endothelial Cells ◽  
Endothelial Cell ◽  
Epithelial Cells ◽  
Human Cytomegalovirus ◽  
Current Data ◽  
Immunosuppressed Patient ◽  
Cell Tropism ◽  
Virus Envelope

In the 1970s–1980s, a striking increase in the number of disseminated human cytomegalovirus (HCMV) infections occurred in immunosuppressed patient populations. Autopsy findings documented the in vivo disseminated infection (besides fibroblasts) of epithelial cells, endothelial cells, and polymorphonuclear leukocytes. As a result, multiple diagnostic assays, such as quantification of HCMV antigenemia (pp65), viremia (infectious virus), and DNAemia (HCMV DNA) in patient blood, were developed. In vitro experiments showed that only low passage or endothelial cell-passaged clinical isolates, and not laboratory-adapted strains, could reproduce both HCMV leuko- and endothelial cell-tropism, which were found through genetic analysis to require the three viral genes UL128, UL130, and UL131 of the HCMV UL128 locus (UL128L). Products of this locus, together with gH/gL, were shown to form the gH/gL/pUL128L pentamer complex (PC) required for infection of epithelial cells/endothelial cells, whereas gH/gL and gO form the gH/gL/gO trimer complex (TC) required for infection of all cell types. In 2016, following previous work, a receptor for the TC that mediates entry into fibroblasts was identified as PDGFRα, while in 2018, a receptor for the PC that mediates entry into endothelial/epithelial cells was identified as neuropilin2 (Nrp2). Furthermore, the olfactory receptor family member OR14I1 was recently identified as a possible additional receptor for the PC in epithelial cells. Thus, current data support two models of viral entry: (i) in fibroblasts, following interaction of PDGFRα with TC, the latter activates gB to fuse the virus envelope with the cell membrane, whereas (ii) in epithelial cells/endothelial cells, interaction of Nrp2 (and OR14I1) with PC promotes endocytosis of virus particles, followed by gB activation by gH/gL/gO (or gH/gL) and final low-pH entry into the cell.

scholarly journals In vitro selection of human cytomegalovirus variants unable to transfer virus and virus products from infected cells to polymorphonuclear leukocytes and to grow in endothelial cells

2001 ◽  
Vol 82 (6) ◽  
pp. 1429-1438 ◽  
Author(s):  
M. Grazia Revello ◽  
Fausto Baldanti ◽  
Elena Percivalle ◽  
Antonella Sarasini ◽  
Luciana De-Giuli ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Human Cytomegalovirus ◽  
Polymorphonuclear Leukocytes ◽  
In Vitro Selection ◽  
Biological Properties ◽  
Lung Fibroblasts ◽  
Human Embryonic Lung ◽  
Infected Cells ◽  
Selection Of

Four human cytomegalovirus (HCMV) isolates from different clinical sources were extensively propagated in human embryonic lung fibroblasts (HELF). Plaque isolates from each of the four virus strains were evaluated for their ability to be transferred to polymorphonuclear leukocytes (PMNL) and to grow in endothelial cells (EC). While all four of the clinical strains were found to be both PMNL- and EC-tropic, variants were identified from each of the four strains that lacked both biological properties, while three of the four parental strains lost their transfer capacity before passage 50 in HELF. It was demonstrated that one of the four field isolates (VR6110) and its transfer-deficient variant were genetically related, but showed different curves of virus yield in HELF. In addition, neither the immediate-early (IE) mRNA nor the IE protein p72 were found to be transferred to PMNL before 72 h post-infection (late in infection) or in the presence of viral DNA replication inhibitors. These findings link EC and PMNL tropism and suggest that PMNL tropism is a late HCMV function.

scholarly journals Inactivation and Disassembly of the Anaphase-Promoting Complex during Human Cytomegalovirus Infection Is Associated with Degradation of the APC5 and APC4 Subunits and Does Not Require UL97-Mediated Phosphorylation of Cdh1

2010 ◽  
Vol 84 (20) ◽  
pp. 10832-10843 ◽  
Author(s):  
Karen Tran ◽  
Jeremy P. Kamil ◽  
Donald M. Coen ◽  
Deborah H. Spector
Keyword(s):  
Human Cytomegalovirus ◽  
De Novo ◽  
Cellular Protein ◽  
Early Gene ◽  
Mass Spectrometry Analysis ◽  
Wild Type Virus ◽  
Viral Gene ◽  
Anaphase Promoting Complex ◽  
Core Complex

ABSTRACT Infection of quiescent cells by human cytomegalovirus (HCMV) elicits severe cell cycle deregulation, resulting in a G1/S arrest, which can be partly attributed to the inactivation of the anaphase-promoting complex (APC). As we previously reported, the premature phosphorylation of its coactivator Cdh1 and/or the dissociation of the core complex can account for the inactivation. We have expanded on these results and further delineated the key components required for disabling the APC during HCMV infection. The viral protein kinase UL97 was hypothesized to phosphorylate Cdh1, and consistent with this, phosphatase assays utilizing a virus with a UL97 deletion mutation (ΔUL97 virus) indicated that Cdh1 is hypophosphorylated at early times in the infection. Mass spectrometry analysis demonstrated that UL97 can phosphorylate Cdh1 in vitro, and the majority of the sites identified correlated with previously characterized cyclin-dependent kinase (Cdk) consensus sites. Analysis of the APC core complex during ΔUL97 virus infection showed APC dissociation occurring at the same time as during infection with wild-type virus, suggesting that the UL97-mediated phosphorylation of Cdh1 is not required for this to occur. Further investigation of the APC subunits showed a proteasome-dependent loss of the APC5 and APC4 subunits that was temporally associated with the disassembly of the APC. Immediate early viral gene expression was not sufficient for the degradation of APC4 and APC5, indicating that a viral early gene product(s), possibly in association with a de novo-synthesized cellular protein(s), is involved.

Characterization of microvascular cell cultures from normotensive and hypertensive rat brains: Pericyte—endothelial cell interactions in vitro

1987 ◽  
Vol 19 (2) ◽  
pp. 197-206 ◽  
Author(s):  
Ira M. Herman ◽  
Patricia M. Newcomb ◽  
John E. Coughlin ◽  
Stanley Jacobson
Keyword(s):  
Endothelial Cell ◽  
Cell Cultures ◽  
Cell Interactions ◽  
Hypertensive Rat

scholarly journals Mutational Mapping of pUL131A of Human Cytomegalovirus Emphasizes Its Central Role for Endothelial Cell Tropism

2011 ◽  
Vol 86 (1) ◽  
pp. 504-512 ◽  
Author(s):  
A. Schuessler ◽  
K. L. Sampaio ◽  
S. Straschewski ◽  
C. Sinzger
Keyword(s):  
Endothelial Cell ◽  
Human Cytomegalovirus ◽  
Cell Tropism ◽  
Mutational Mapping

Cell-cycle-dependent localization of human cytomegalovirus UL83 phosphoprotein in the nucleolus and modulation of viral gene expression in human embryo fibroblasts in vitro

2011 ◽  
Vol 112 (1) ◽  
pp. 307-317 ◽  
Author(s):  
Maria-Cristina Arcangeletti ◽  
Isabella Rodighiero ◽  
Prisco Mirandola ◽  
Flora De Conto ◽  
Silvia Covan ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Cycle ◽  
Human Cytomegalovirus ◽  
Human Embryo ◽  
Viral Gene Expression ◽  
Viral Gene ◽  
Embryo Fibroblasts ◽  
Cycle Dependent

scholarly journals Pleural Fluid Has Pro-Growth Biological Properties Which Enable Cancer Cell Proliferation

2021 ◽  
Vol 11 ◽  
Author(s):  
Rachelle Asciak ◽  
Nikolaos I. Kanellakis ◽  
Xuan Yao ◽  
Megat Abd Hamid ◽  
Rachel M. Mercer ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Pleural Fluid ◽  
Cancer Cell ◽  
Cell Cultures ◽  
Biological Properties ◽  
Cancer Cell Proliferation ◽  
Different Types ◽  
Pleural Metastases ◽  
Similar Growth

ObjectivesPatients with malignant pleural mesothelioma (MPM) or pleural metastases often present with malignant pleural effusion (MPE). This study aimed to analyze the effect of pleural fluid on cancer cells.Materials and MethodsEstablished patient-derived cancer cell cultures derived from MPE (MPM, breast carcinoma, lung adenocarcinoma) were seeded in 100% pleural fluid (exudate MPM MPE, transudate MPE, non-MPE transudate fluid) and proliferation was monitored. In addition, the establishment of new MPM cell cultures, derived from MPE specimens, was attempted by seeding the cells in 100% MPE fluid.ResultsAll established cancer cell cultures proliferated with similar growth rates in the different types of pleural fluid. Primary MPM cell culture success was similar with MPE fluid as with full culture medium.ConclusionsPleural fluid alone is adequate for cancer cell proliferation in vitro, regardless of the source of pleural fluid. These results support the hypothesis that pleural fluid has important pro-growth biological properties, but the mechanisms for this effect are unclear and likely not malignant effusion specific.

scholarly journals Cellular and Viral Control over the Initial Events of Human Cytomegalovirus Experimental Latency in CD34+ Cells

2010 ◽  
Vol 84 (11) ◽  
pp. 5594-5604 ◽  
Author(s):  
Ryan T. Saffert ◽  
Rhiannon R. Penkert ◽  
Robert F. Kalejta
Keyword(s):  
Gene Expression ◽  
Human Cytomegalovirus ◽  
Nuclear Body ◽  
Immune Defense ◽  
Lytic Infection ◽  
Viral Gene ◽  
Viral Control ◽  
Clinical Strains ◽  
Early Protein

ABSTRACT Human cytomegalovirus (HCMV) persists for the life of its host by establishing a latent infection. The identification of viral and cellular determinants of latency is the first step toward developing antiviral treatments that target and might clear or control the reservoir of latent virus. HCMV latency is established in CD34+ cells when expression of viral immediate early (IE) proteins that initiate lytic infection is silenced. Viral IE gene expression during lytic infection is controlled by a cellular intrinsic immune defense mediated by promyelocytic leukemia nuclear body (PML-NB) proteins such as Daxx and histone deacetylases (HDACs). This defense is inactivated at the start of lytic infection by the HCMV virion tegument protein pp71, which upon viral entry traffics to the nucleus and induces Daxx degradation. Here we show that a similar defense is present, active, and not neutralized during experimental latency in CD34+ cells infected in vitro because tegument-delivered pp71 remains in the cytoplasm. Artificial inactivation of this defense by HDAC inhibition or Daxx knockdown rescues viral IE gene expression upon infection of CD34+ cells with a laboratory-adapted viral strain but not with clinical strains. Interestingly, coinfection of CD34+ cells with clinical viral strains blocked the ability of an HDAC inhibitor to activate IE1 and early protein expression during infection with a laboratory-adapted strain. This suggests that in addition to the intrinsic defense, HCMV clinical strains contribute an HDAC-independent, trans-acting dominant means of control over viral gene expression during the early stages of experimental HCMV latency modeled in vitro in CD34+ cells.

scholarly journals Metabolic response of blood vessels to TNFα

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Abidemi Junaid ◽  
Johannes Schoeman ◽  
Wei Yang ◽  
Wendy Stam ◽  
Alireza Mashaghi ◽  
...  
Keyword(s):  
Endothelial Cell ◽  
Cell Cultures ◽  
Inflammatory Responses ◽  
Metabolic Response ◽  
Three Dimensional ◽  
Two Dimensional ◽  
Bioactive Lipids ◽  
Liquid Chromatography Tandem Mass ◽  
Endothelial Cell Cultures

TNFα signaling in the vascular endothelium elicits multiple inflammatory responses that drive vascular destabilization and leakage. Bioactive lipids are main drivers of these processes. In vitro mechanistic studies of bioactive lipids have been largely based on two-dimensional endothelial cell cultures that, due to lack of laminar flow and the growth of the cells on non-compliant stiff substrates, often display a pro-inflammatory phenotype. This complicates the assessment of inflammatory processes. Three-dimensional microvessels-on-a-chip models provide a unique opportunity to generate endothelial microvessels in a more physiological environment. Using an optimized targeted liquid chromatography–tandem mass spectrometry measurements of a panel of pro- and anti-inflammatory bioactive lipids, we measure the profile changes upon administration of TNFα. We demonstrate that bioactive lipid profiles can be readily detected from three-dimensional microvessels-on-a-chip and display a more dynamic, less inflammatory response to TNFα, that resembles more the human situation, compared to classical two-dimensional endothelial cell cultures.

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