The human cytomegalovirus (HCMV) is a widespread herpesvirus. Virus reactivation from latency can lead to stillbirth, miscarriage, fetal anomalies, and intrauterine growth retardation. During latent infection with the HCMV, the virus can be cleared by the immune response or apoptosis of host cells. However, the HCMV has developed several strategies to manipulate expression of its genes and the microenvironment of host cells. Recent studies have shown that latent infection with the HCMV is associated with viral: regulation of early expression of genes; evasion of cell death; evasion of the immune response; regulatin of non-coding RNAs. This review summarizes recent research progress on the mechanisms underpinning latent infection with the HCMV.
Animals ; Cytomegalovirus ; genetics ; physiology ; Cytomegalovirus Infections ; immunology ; virology ; Humans ; Viral Proteins ; genetics ; metabolism ; Virus Latency

BACKGROUNDCloning recombinant human Fab fragment against HCMV for the purpose of prophylaxis and control of HCMV infection.

METHODSThe authors constructed a HCMV phage display library with 2 x 10(6) clones, then used purified HCMV viral lysates to pan the library, then screened by ELISA.

RESULTSThree clones showed positive responses in ELISA, they also showed high specificity in IFA, two of them could neutralize HCMV in neutralizing assays.

CONCLUSIONThe specific binding of Fab antibodies to HCMV was demonstrated by ELISA, IFA and neutralizing activities. These results provide us the basis for further research of neutralizing recombinant human whole IgG molecule.

Antibodies, Viral ; genetics ; immunology ; Cytomegalovirus ; genetics ; immunology ; Cytomegalovirus Infections ; immunology ; virology ; Escherichia coli ; genetics ; metabolism ; Gene Expression ; Humans ; Immunoglobulin Fab Fragments ; genetics ; immunology ; Neutralization Tests ; Peptide Library

Biomarkers ; metabolism ; CD4-Positive T-Lymphocytes ; immunology ; metabolism ; Cytomegalovirus Retinitis ; immunology ; Female ; Humans ; Male ; Polymerase Chain Reaction ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; immunology ; metabolism ; virology

BACKGROUND: The dramatic increase in use of the IgG test for toxoplasma, rubella, cytomegalovirus (CMV), and herpes simplex virus (HSV) [TORCH] has led to the requirement for a high-efficiency method that can be used in the clinical laboratory. This study aimed to compare the results of BGI-Array ELISA TORCH IgG (BGI-GBI, China) screening method to those of Virion/Serion TORCH IgG ELISA (Virion/Serion, Germany). METHODS: Serum specimens (n=400) submitted for routine IgG testing by Virion/Serion ELISA were also tested using the BGI-Array ELISA method. The agreements of these two kinds of method were analyzed by kappa-coefficients calculation. RESULTS: Following repeat testing, the BGI-Array ELISA TORCH IgG assays demonstrated agreements of 99.5% (398/400 specimens), 98% (392/400 specimens), 99% (396/400 specimens), and 99.5% (398/400 specimens), respectively. The BGI-Array ELISA IgG assays provided results comparable to Virion/Serion ELISA results, with kappa-coefficients showing near-perfect agreement for the HSV (kappa=0.87), rubella (kappa=0.92) and CMV (kappa=0.93) and substantial agreement for the toxoplasma (kappa=0.80) IgG assays. The use of the BGI-Array ELISA TORCH IgG assays could reduce the turnaround time (1.5 hr vs. 5 hr by Virion/Serion ELISA for 100 specimens) and were easy to use. CONCLUSIONS: BGI-Array ELISA TORCH IgG shows a good agreement with Virion/Serion ELISA methods and is suitable for clinical application.
Antibodies, Viral/blood ; Cytomegalovirus/immunology/*metabolism ; *Enzyme-Linked Immunosorbent Assay ; Humans ; Immunoglobulin G/*analysis/blood ; Protozoan Infections/diagnosis ; Reagent Kits, Diagnostic ; Rubella virus/immunology/*metabolism ; Sensitivity and Specificity ; Simplexvirus/immunology/*metabolism ; Toxoplasma/immunology/*metabolism ; Virion/*immunology/metabolism ; Virus Diseases/diagnosis

BACKGROUND: Quantitation of cytomegalovirus (CMV) DNA using real-time PCR has been utilized for monitoring CMV infection. However, the CMV antigenemia assay is still the 'gold standard' assay. There are only a few studies in Korea that compared the efficacy of use of real-time PCR for quantitation of CMV DNA in whole blood with the antigenemia assay, and most of these studies have been limited to transplant recipients. METHOD: 479 whole blood samples from 79 patients, falling under different disease groups, were tested by real-time CMV DNA PCR using the Q-CMV real-time complete kit (Nanogen Advanced Diagnostic S.r.L., Italy) and CMV antigenemia assay (CINA Kit, ArgeneBiosoft, France), and the results were compared. Repeatedly tested patients were selected and their charts were reviewed for ganciclovir therapy. RESULTS: The concordance rate of the two assays was 86.4% (Cohen's kappa coefficient value=0.659). Quantitative correlation between the two assays was a moderate (r=0.5504, P<0.0001). Among 20 patients tested repeatedly with the two assays, 13 patients were transplant recipients and treated with ganciclovir. Before treatment, CMV was detected earlier by real-time CMV DNA PCR than the antigenemia assay, with a median difference of 8 days. After treatment, the antigenemia assay achieved negative results earlier than real-time CMV DNA PCR with a median difference of 10.5 days. CONCLUSIONS: Q-CMV real-time complete kit is a useful tool for early detection of CMV infection in whole blood samples in transplant recipients.
Antiviral Agents/therapeutic use ; Cytomegalovirus/*genetics ; Cytomegalovirus Infections/drug therapy/pathology/virology ; DNA, Viral/*blood/metabolism ; Ganciclovir/therapeutic use ; Humans ; *Immunoassay ; Organ Transplantation ; Phosphoproteins/genetics/immunology/*metabolism ; *Real-Time Polymerase Chain Reaction ; Viral Matrix Proteins/genetics/immunology/*metabolism ; Virology/*methods

BACKGROUNDRheumatic diseases involve multiple organs that are affected by immunological mechanisms. Treatment with corticosteroids and immunosuppressive agents may also increase the frequency of infection. Cytomegalovirus (CMV) is a widespread herpes virus and a well-recognized pathogen, which causes an opportunistic and potentially fatal infection in immunocompromised patients. This retrospective study aimed to investigate the clinical and laboratory characteristics of CMV pneumonia in patients with rheumatic diseases after immunosuppressive therapy in a single center in Shanghai, China.

METHODSEight hundred and thirty-four patients with rheumatic diseases who had undergone CMV-DNA viral load tests were included, and the medical records of 142 patients who were positive for CMV-DNA in plasma samples were evaluated. GraphPad Prism version 5.013 (San Diego, CA, USA) was used to conduct statistical analysis. The correlation between CMV-DNA viral loads and lymphocyte counts was assessed using the Spearman rank correlation coefficient test. Significance between qualitative data was analyzed using Pearson's Chi-squared test. The cut-off thresholds for CMV-DNA viral load and lymphocyte count were determined by receiver operating characteristic (ROC) curve analysis.

RESULTSOne hundred and forty-two patients had positive CMV viral load tests. Of these 142 patients, 73 patients with CMV pneumonia were regarded as symptomatic, and the other 69 were asymptomatic. The symptomatic group received higher doses of prednisolone (PSL) and more frequently immunosuppressants than the asymptomatic group (P < 0.01). The symptomatic group had lower lymphocyte counts, especially CD4+ T-cells, than the asymptomatic group (P < 0.01). By ROC curve analysis, when CD4+ T-cell count was <0.39 × 109/L, patients with rheumatic diseases were at high risk for symptomatic CMV infection. The CMV-DNA load was significantly higher in the symptomatic patients than that in asymptomatic patients (P < 0.01; threshold viral loads: 1.75 × 104 copies/ml). Seven patients had a fatal outcome, and they had lower peripheral lymphocyte counts (P < 0.01), including CD4+ and CD8+ T-cells (P < 0.01).

CONCLUSIONSWhen CD4+ T-cell count is <0.39 × 109/L, patients are at high risk for pulmonary CMV infection. Patients are prone to be symptomatic with CMV-DNA load >1.75 × 104 copies/ml. Lymphopenia (especially CD4+ T-cells), presence of symptoms, and other infections, especially fungal infection, are significant risk factors for poor outcome, and a higher PSL dosage combined with immunosuppressants may predict CMV pneumonia.

CD4-Positive T-Lymphocytes ; metabolism ; China ; Cytomegalovirus ; pathogenicity ; Cytomegalovirus Infections ; genetics ; immunology ; therapy ; virology ; Humans ; Immunosuppression ; methods ; Pneumonia ; genetics ; immunology ; therapy ; virology ; Polymerase Chain Reaction ; Retrospective Studies ; Rheumatic Diseases ; genetics ; immunology ; therapy ; virology ; Viral Load

The N-terminal segment (FR-1) of the heavy chain (VH) of antibodies may have a great impact on IgG secretion in Escherichia coli and other hosts. Decrease in secretion may be caused by a single amino acid change in the framework region. To investigate the high antibody expression in mammalian cells, we designed the site-directed mutagenesis of the FR-I of the pCMV-RV/VH gene,which expressed the immunoglobulin heavy chain of human anti-Rabies virus antibody. Mutating Glu (H6) to Gln could improve both antibody secretion and affinity. The immunofluorescence assay indicated that both the secretion-deficient antibodies and the secretion- efficient antibodies could be transcribed and translated intracellularly, and led into ER,then transferred to Golgi apparatus,and the difference in secretion may relate to the contribution of the FR-I to the folding and assembly of the antibody. In this study, we have confirmed experimentally that the nature of residues H6 in antibody heavy chains indeed determines the antibody secretion in mammalian cells. These results also provide the basis for antibody production.
Animals ; Antibodies ; genetics ; immunology ; metabolism ; Antibodies, Viral ; genetics ; immunology ; metabolism ; Antibody Affinity ; Biological Transport ; COS Cells ; Cercopithecus aethiops ; Cytomegalovirus ; genetics ; Endoplasmic Reticulum ; metabolism ; Enzyme-Linked Immunosorbent Assay ; Fluorescent Antibody Technique ; Glycoproteins ; genetics ; immunology ; Golgi Apparatus ; metabolism ; Humans ; Immunoglobulin Fragments ; genetics ; immunology ; Immunoglobulin Heavy Chains ; chemistry ; genetics ; immunology ; Immunoglobulin Variable Region ; chemistry ; genetics ; immunology ; Mutagenesis, Site-Directed ; Plasmids ; genetics ; Rabies virus ; genetics ; immunology ; metabolism

OBJECTIVETo explore the clinical value of determination of ATP levels in CD4(+) cells of patients with cytomegaloviral pneumonia after kidney transplantation.

METHODSTwenty-eight patients with cytomegaloviral pneumonia following kidney transplantation and 30 healthy volunteers were enrolled in this study. ATP-bioluminescence assay (ATP-CVA) was used to assess the immune response of CD4(+) cells to phytohemagglutinin (PHA) stimulation in the normal volunteers and the recipients (before and at 1, 2, and 4 weeks after renal transplantation, before and at 2 and 4 week after the treatment).

RESULTSATP concentration in CD4(+) cells of the recipients was 402-/+58 ng/ml before the operation, significantly lower than that in normal volunteers (458-/+196 ng/ml, P<0.05), and reached the lowest level in the first week after operation especially in the recipients with antibody-inducing therapy; ATP level increased slowly since week 2 post-operation, but still remained significantly lower than the preoperative by the fourth week (266-/+87 ng/ml, P<0.05), especially in the recipients receiving antibody-inducing therapy. In the event of cytomegaloviral pneumonia, ATP level underwent a mild reduction to 152-/+78 ng/ml in comparison with the postoperative level at the first week (P>0.05), and was significantly lower than preoperative level (P<0.01); the decrease was especially obvious during the exacerbation of the condition. ATP level then increased slowly after effective treatment, but was still lower than the preoperative level at 4 weeks after the operation (336-/+92 ng/ml, P<0.05).

CONCLUSIONThe determination of ATP level in CD4(+) cells allows more accurate assessment of the cellular immunity in the renal transplant recipients with cytomegaloviral pneumonia to help in the clinical treatment of the patients.

Adenosine Triphosphate ; blood ; Adult ; Aged ; CD4-Positive T-Lymphocytes ; metabolism ; Case-Control Studies ; Cytomegalovirus Infections ; immunology ; Female ; Humans ; Kidney Transplantation ; Male ; Middle Aged ; Pneumonia, Viral ; immunology ; metabolism ; virology ; Postoperative Complications ; immunology ; metabolism ; Young Adult

Cytomegalovirus (CMV) infection is a dangerous complication in patients with chronic graft versus host disease (cGVHD). CMV-specific immunity depends on the activity of T cells. This study was aimed to investigate the effect of CMV pp65 gene modified dendritic cells (DCs) on activation of autologous T cells. Lentivirus system was utilized to introduce the CMV full-length pp65 gene into mouse DCs; CpG-DNA was used to induce mature DCs; flow cytometry and immunofluorescence were used to determine the expression of antigen and IFNgamma in T lymphocytes. The results showed that the DCs were infected with lentivirus at a multiplicity of infection (MOI) of 50 with optimal infectious efficiency of 30%-40%; mature DCs expressing pp65 gene could stimulate autologous naive T cells to express CD69 specifically; mature DCs expressing PP65 could stimulate autologous CD4+ or CD8+ T cells to produce IFNgamma. It is concluded that CMV pp65-modified and CpG-DNA-induced mature DCs can activate CMV-specific T lymphocytes in vitro.
Animals ; Antigens, CD ; genetics ; metabolism ; Antigens, Differentiation, T-Lymphocyte ; genetics ; metabolism ; Antigens, Viral ; immunology ; CD4-Positive T-Lymphocytes ; immunology ; CD8-Positive T-Lymphocytes ; immunology ; CpG Islands ; genetics ; Cytomegalovirus ; immunology ; DNA ; genetics ; Dendritic Cells ; cytology ; immunology ; metabolism ; Humans ; Interferon-gamma ; genetics ; metabolism ; Lectins, C-Type ; Lentivirus ; genetics ; metabolism ; Mice ; Phosphoproteins ; genetics ; metabolism ; Viral Matrix Proteins ; genetics ; metabolism

Quantification of cytotoxic T lymphocytes (CTL) is extremely important due to the pivotal role they play in controlling pathogen infection and anti-tumor actions. Previously used methods for detecting specific CTL are usually indirect. In recent years, tetramer technology has been developed to directly visualize antigen-specific CTL efficiently, and become the critical approach in studying T cell immune responses. A simplified procedure for preparing tetramers is reported here in this paper and a tetramer loaded with human cytomegalovirus (HCMV) peptide was successfully obtained using this procedure, which possessed binding activity with specific CTL. The heavy chain of HLA-A * 0201 gene was cloned by RT-PCR from HLA-A2+ donor. An expression vector, encoding the extracellular domain of HLA-A * 0201 heavy chain (A2) fused with a BirA substrate peptide (BSP) at its carboxyl terminus, was constructed by PCR with cloned A2 gene as the template. The A2 heavy chain was expressed in Escherichia coli mostly in the form of inclusion body and purified by washing inclusion body. The monomer of soluble A2 loaded with peptide was reconstructed by dilution from the heavy chain in the presence of light chain beta2-microglobulin and HLA-A2 restricted HCMV pp65(495-503) peptide (NLVPMVATV, NLV). Refolded A2-NLV monomer was biotinylated with a commercial BirA and purified by low pressure anion exchange chromatography on a Q-Sepharose (fast flow) column. The tetramer was then formed by mixing A2-NLV monomer with streptavidin-PE in a ratio of 4:0.8 leading to more than 85% multiplication as revealed by SDS-PADE under non-reducing conditions without boiling the sample. Flow cytometry analysis indicated that this tetramer could bind to specific CTL from HLA-A2+ donor. In conclusion, a simplified procedure is established to prepare HLA-A2 tetramer, which may not only facilitate the application of tetramer technology for studying specific T lymphocyte immune response but A2-NLV itself be applied clinically to monitor CMV-specific CTL in stem cell and organ transplantation.
Cloning, Molecular ; Cytomegalovirus ; genetics ; immunology ; Escherichia coli ; genetics ; metabolism ; HLA-A Antigens ; biosynthesis ; genetics ; immunology ; HLA-A2 Antigen ; Humans ; Phosphoproteins ; biosynthesis ; genetics ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; T-Lymphocytes, Cytotoxic ; immunology ; metabolism ; Viral Matrix Proteins ; biosynthesis ; genetics