• Journal of Microbiology and Biotechnology
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• v.23 no.8
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• pp.1154-1158
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• 2013

Ganciclovir resistance of human cytomegalovirus is associated with mutations in the viral UL97 gene and poses severe problems for immunocompromised patients. In this study, PCR-based restriction fragment length polymorphism and sequencing analyses detected the UL97 D605E mutation in all five clinical isolates from patients with ganciclovir-resistant human cytomegalovirus infection during prolonged ganciclovir therapy, whereas the M460V mutation was only present in 1 of 5 isolates. On the other hand, the detection rates of the D605E mutation in the stored available DNA samples from the donor and allogeneic stem cell transplantation recipients were 66.7% and 93.7%, respectively, suggesting that the presence of D605E mutation was not associated with the ganciclovir exposure. Although the D605E mutation may not be related to ganciclovir resistance, we suggest that this mutation could be an important molecular marker of human cytomegalovirus evolution in East Asian countries. Moreover, the restriction fragment length polymorphism method using the restriction enzyme HaeIII, which is generally used to detect the UL97 A591V mutation, could also detect the D605E mutation and may therefore be a useful tool for future research on the investigation of UL97 gene mutations.

• Korean Journal of Microbiology
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• v.29 no.1
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• pp.25-33
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• 1991

Antiviral activities of papaverine and nucleoside analogs, 9-[(1,3-dihydroxy-2-propoxy)methyl]guanine (DHPG) and acyclovir, against human cytomegalovirus (HCMV) infection were compared in vitro. Papaverine and DHPG were effective in reducing infectious HCMV yields with $ED_{50}{\s}$ (effective dose 50: the concentraion at which 50% of virus yields was obtained) of approximately 1.02 and $0.45{\mu}{\M}$, respectively; while acyclovir was less effective with an $ED_{50}$ of about $10.4{\mu}{\M}$The relative cytotoxicity of these drugs was evaluated under the same conditions used to measure infectious HCMV yields. Papaverine and DHPG demonstrated little cellular toxicity as measured by their effect on the viability of confluent cells at concentrations in the range of those demonstrating potent inhibition of HCMV replication. Similarly, protein synthesis was largely unaffected by these drugs in stationary mock-infected cells as measured by the incorporation of isotopically labelled amino acids. In contrast, cellular DNA synthesis was invariably reduced in the presence of either drug. HCMV-specific DNA synthesis was also strongly inhibited by papaverine and DHPG.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.10a
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• pp.660-662
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• 2010

To control replication of human cytomegalovirus (HCMV) effectively, inhibitors of peptide nucleic acids (PNA) with a gene delivery agent, PEI (polyethylenimine) against HCMV were applied. The transfection of these PNA inhibitors with PEI agent into host cells showed synergic inhibition effect of HCMV replication. These inhibition effect was confirmed by methods of RT-PCR, CPE, real-time-PCR, and Western blot.

• Korean Journal of Microbiology
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• v.37 no.2
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• pp.145-150
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• 2001

Reactivation of human cytomegalovirus (HCMV) from latency is often fatal to immunocompromised individuals. To understand the effect of HCMV on human monocytes where HCMV establishes latency, two human monocyte cell lines at different stages in differentiation, THP-1 and HL-60 were infected with HCMV. While the viability and morphology of HL-60 cells were not significantly affected by HCMV, the viability of THP-1 cells was dramatically decreased by HCMV infection. THP-1 cells infected with HCMV became aggregated and adhered to the surface of culture dishes, probably due to the increased expression of adherence molecules CD11b on the infected THP-1 cells. THP-1 cells established a latent HCMV infection were induced to differentiate by treatment with TPA and hydrocortisone. Recovery of infectious HCMV from the culture supernatant of differentiated THP-1 cells was dependent on the time of induction of differentiation after HCMV infection. Thus, in vitro model of reactivation of HCMV from latently infected monocytes was established.

• Journal of Microbiology
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• v.40 no.3
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• pp.224-229
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• 2002

The effect of human cytomegalovirus (HCMV) on three human monocyte cell lines at different stages of differentiation was investigated. While the viability of HL-60 cells or U-937 cells was not significantly affected by HCMV infection, the viability of THP-1 cells was reduced. Acridine orange/ethidiurn bromide staining revealed that the reduction of THP-1 cell viability was due to increased apoptotic death following HCMV infection. Apoptosis in HL-60 cells was not affected by HCMV infection, and induction of apoptosis of U-937 cells by HCMV was intermediate between HL-60 and THP-1 cells. Since HL-60 cells are the least differentiated and THP-1 cells are the most differentiated, the induction of apoptosis of human monocytes appears to be related to the degree of cell differentiation. Flow cytometric and confocal microscopic studies using fluorescent calcium indicator Fluo-3 suggested a significant increase in intracellular free calcium concentration (［Ca$\^$2+/］i) in THP-1 cells undergoing apoptosis by HCMV infection. Again ［Ca$\^$2+/］i in HCMV-infected HL-60 cells was not critically altered, and that in HCMV-infected U-937 cells was intermediate between THP-1 cells and HL-60 cells. Calcium influx blockers such as verapamil and nifedipine partially reversed HCMV-induced apoptosis in THP-1 cells.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.3
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• pp.1453-1457
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• 2014

Background: The association of colorectal cancer with human cytomegalovirus (HCMV) is a controversial issue in cancer research. This study aimed to identify the HCMV virus in colorectal cancer tissues and to investigate the association of HCMV with colorectal cancer. In this study, 50 cancer tissue samples and 50 samples without colon cancer were studied in order to identify the HCMV virus through nested-polymerase chain reaction. The virus was identified in 15 cases of colorectal cancer tissues (15/50) and in 5 cases of normal tissues (5/50). Eight cases of adenocarcinoma tissues were in a moderately differentiated stage, and 7 cases had well-differentiated stage tissues that were positive for viral DNA. The findings were statistically evaluated at a significance level of p<0.05. The HCMV virus could playa role in creating malignancy and the progress of cancer through the process of oncomodulation.

• Parasites, Hosts and Diseases
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• v.30 no.1
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• pp.53-58
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• 1992

This 54-year-old Korean coal miner soBered from continuous watery diarrhea and weight loss after corticosteroid treatment(${\beta}-methasone$, 4 mg daily for 1 week) due to hip-bone fracture in January 1991. Except for the short therapy f steroid, no other histories were contributory. The malabsorption syndrome was aggravated while the case was treated under the impression of amebiasis or intestinal tuberculosis. AIDS antibody test by EIA was negative and quantitative analysis of serum immunoglobulins was in normal ranges. Nine months after the onset of symptoms, the case was diagnosed as malabsorption syndrome caused by complected and aggravated infection by Strengyleides stercoralis, Isospora and cytomegalovirus in the small intestine, which were proved by stool examination and duodenal biopsy. His clinical course became worse even after high-dosaged and prolonged albendazole treatment for strongyloidiasis with supportive quid therapy. The patient was discharged in hopeless status in November, 1991 and died after one week at home.

• Journal of Microbiology
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• v.35 no.2
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• pp.152-157
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• 1997

Infection of human fibroblast (HF) cells with human cytomegalovirus (HCMV) result in changes in the intracellular level of second messengers. Since nitric oxide (NO) production has been known to be related with other second messengers, it is probable that HCMV infection of HF cells may involve NO. To test this possibility, the amount of NO was measured following ogenous addition of NO generators such as sodium nitroprusside (SNP) or S-nitroso-N-a-cetylpenicillamine (SNAP) immediately after HCMV infection, however, inhibited virus multiplication. Furthermore, immunoblot experiment using monoclonal antibody to HCMV major immediate early (MIE) proteins or CAT assay using pCMVIE/CAT (plasmid containing CAT gene driven by HCMV MIE promoter) revealed that SNP or SNAP blocked the MIE gene expression. SNP was more effective than SNAP in hibiting HCMV multiplication or MIE gene expression. SNP produced more NO than SNAP in inhibiting HCMV multiplication or MIE gene expression. SNP produced more NO than SNAP. Although the mechanism for the inhibition of HCMV multiplication and MIE gene expression by NO is still elusive some correlation with NO-mediated inhibition of HCMV-induced increase in cytosolic free Ca$\^$2+/ concentration ([Ca$\^$2+/]) was observed. The increase of [Ca$\^$2+/] following HCMV infection was inhibited by SNP, and less effectively by SNAP. Raising [Ca$\^$2+/ with bromo-A23187 partially reversed the SNP block of MIE gene expression. Thus, there appear to e some relationships among NO. [Ca$\^$2+/], and HCMV MIE gene expression.

• Journal of Microbiology
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• v.38 no.4
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• pp.255-259
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• 2000

For rapid and sensitive measurement of antiviral activities, application of a recombinant virus containing firefly luciferase gene was attempted. Recombinant human cytomegalovirus (HCMV) containing luciferase gene driven by HCMV late gene pp28 promoter (HCMV/pp28-luc) was used to test the antiviral activities of three known compounds and the result was compared with results from the conventional plaque assay for measuring the production of infectious viruses. When human fibroblast cells were infected with HCMV/pp28-luc, luciferase activity was observed at 2 days after infection and reached maximum at 6 days after infection, whereas the production of infectious virus was maximal at 4 days after infection. The antiviral activities of ganciclovir, acyclovir, and papaverine were measured in HFF cells infected with HCMV/PP28-luc and the luciferase activity was compared with the infectious virus titers. Luciferase activity decreased as the concentration of ganciclovir or papaverine increased, while there was a slight decrease in luciferase activity with acyclovir. The level of the decrease in Luciferase activity was comparable to the level of decrease in the production of infectious virus. Therefore, the antiviral assay using recombinant virus HCMV/pp28-luc resulted in sensitivity similar to the conventional plaque assay with a significant reduction in assay time.

• The Journal of Korean Society of Virology
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• v.29 no.4
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• pp.261-269
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• 1999

The relationship between second messenger cGMP and human cytomegalovirus (HCMV) replication was investigated. First, the intracellular level of cGMP ([cGMP]i) in HCMV-infected cells was measured. The [cGMP]i increased at early times after HCMV infection, reached maximum level at 12 hr and returned to basal level at 24 hr after virus infection, while [cGMP]i in mock-infected cells remained relatively unchanged. Increasing [cGMP]i resulted in enhanced transcription of HCMV major immediate early gene. For early gene expression, cGMP had varying effect. Expression of 1.2 kb RNA decreased and 2.2 kb RNA increased with increasing cGMP, while 2.7 kb RNA gene expression was not affected. HCMV early genes are regulated by immediate early gene, and the effect of cGMP on the regulatory effect of major immediate early gene on early genes was investigated. In the absence of cGMP, major immediate early gene repressed 2.7 kb RNA gene expression, while 1.2 kb RNA and 2.2 kb RNA early genes were not significantly affected. In the presence of $1\;{\mu}M$ cGMP, however, major immediate early gene stimulated the expression of three early genes.