Relationship of genotypes of hepatitis B virus to mutations, disease progression and response to antiviral therapy

SUMMARY: Phylogenetic analysis has led to the classification of hepatitis B virus into eight genotypes, designated A to H. The genotypes have differences in biological properties and show heterogeneity in their global distribution. These attributes of the genotypes may account not only for differences in the prevalence of hepatitis B virus mutants in various geographic regions, but also be responsible for differences in the clinical outcome and response to antiviral treatment in different population groups.     

造血干细胞移植后巨细胞病毒感染患者糖蛋白B基因分型的初步研究

目的初步探讨造血干细胞移植(HSCT)后巨细胞病毒(CMV)感染患者CMV糖蛋白(G)B基因分型及其与致病性的关系。方法研究了2001年3月至2003年12月在我院行HSCT的患者38例,均采用巢式PCR方法检测CMV GBDNA为阳性,对PCR产物用RsaⅠ和HinfⅠ内切酶进行了酶切分型。结果Ⅰ型19/38例(50.0%),Ⅱ型3/38例(7.9%),Ⅲ型14/38例(36.8%),Ⅰ与Ⅲ混合型2例。Ⅰ型感染预后良好,Ⅲ型与致死性间质性肺炎(IP)发生有明显的相关性。Ⅰ、Ⅲ型患者移植物抗宿主病(GVHD)的发生率差异无统计学意义。结论CMVGB蛋白的基因分型与CMV的IP发生有关,与GVHD的发生无明显相关性。     

Cytomegalovirus (CMV) virus load kinetics to predict recurrent disease in solid-organ transplant patients with CMV disease

Despite standard therapy, cytomegalovirus (CMV) disease recurs in a significant proportion of organ transplant recipients. The kinetics of CMV load in response to therapy may allow early prediction of recurrence. CMV loads were obtained at regular intervals after starting ganciclovir therapy in 52 transplant recipients with CMV disease. Virus load kinetics were analyzed using decay curves to assess viral dynamics, including half-life and time to viral clearance. Recurrent CMV disease occurred in 12 (23%) of 50 patients. The time period to viral clearance was longer among patients with recurrence of CMV disease (P=.002), and lack of clearance was also associated among patients with disease recurrence (P<.001). Viral kinetics followed a logarithmic decay curve expressed by the equation y=y(0)e(-ax). Virus load half-life was 8.8 days among patients with recurrence versus 3.17 days among patients without recurrence (P=.001). This was not explainable by detectable ganciclovir resistance. CMV load kinetics are useful for identifying, at a very early stage, patients who are more likely to have recurrence.     

Salivary cytomegalovirus (CMV) shedding, glycoprotein B genotype distribution, and CMV disease in human immunodeficiency virus-seropositive patients.

To assess the frequency of shedding of cytomegalovirus (CMV) in saliva, the distribution of CMV glycoprotein B (gB) genotypes, and the occurrence of CMV diseases, we screened 98 human immunodeficiency virus (HIV)-seropositive patients without CMV disease. CMV was detected by culture more frequently in saliva (45 [46%] of 98 patients) than in blood (7 [7.5%] of 93) and was associated with CD4 cell counts <100 cells/mm3 (P=.013). CMV in the saliva of 37 patients was successfully genotyped. Three patients (8%) were infected by a gB1 strain, 26 (70%) by a gB2 strain, 2 (5.5%) by a gB3 strain, 1 (3%) by a gB4 strain, and 5 (13.5%) by mixed gB strains. Thirteen patients developed CMV disease after a mean period of 143+/-112 days; at inclusion, 9 (69%) had salivary CMV shedding and 2 had CMV viremia. CMV salivary shedding (P=.043), low CD4+ cell count (P=.041), and CMV viremia (P=.011) were associated with occurrence of CMV disease.     

Cytomegalovirus (CMV) DNA load in plasma for the diagnosis of CMV disease before engraftment in hematopoietic stem-cell transplant recipients

Among hematopoietic stem-cell transplant (HSCT) recipients, cytomegalovirus (CMV) disease before engraftment is rare but often fatal, and cell-based diagnostic tests have low sensitivity in this clinical setting. We used the quantitative real-time polymerase chain reaction (PCR) assay to test for CMV DNA in plasma samples from 15 HSCT recipients who developed CMV disease before engraftment and from 33 matched control patients. CMV DNA was detected in plasma in 14 (93.3%) of the 15 patients who had CMV disease before engraftment, compared with 5 (15.2%) of 33 control patients (P<.001). CMV DNA was detected a median of 13 days before the onset of CMV disease (range, 0-35 days). The maximum CMV virus load in plasma was >1 log(10) higher among case patients than among control patients (median, 1700 [range, 50 to 5.5x107] vs. <50 [range, <50-350] CMV DNA copies/mL plasma, respectively; P<.001). Quantitative PCR for CMV DNA in plasma appears to be useful for the identification of HSCT recipients at risk for CMV disease before engraftment.     

Cytomegalovirus (CMV) blood DNA load, CMV retinitis progression, and occurrence of resistant CMV in patients with CMV retinitis

BACKGROUND. The amount of cytomegalovirus (CMV) DNA in the blood (CMV load) may be a marker for detection of resistant CMV.METHODS. A total of 165 patients with AIDS and CMV retinitis had CMV load measurements (plasma and leukocyte) and cultures performed every 3 months; these measurements were correlated with CMV resistance to antiviral drugs and CMV retinitis progression (from masked readings of retinal photographs).RESULTS. Detectable plasma and leukocyte CMV loads were associated with CMV retinitis progression (odds ratios [OR], 6.3; P<.0001 and OR, 6.6; P<.0001, respectively), phenotypic resistance (OR, 6.1; P<.0001 and OR, 23.4; P=.0002, respectively), and genotypic resistance (OR, 17.5; P<.0001 and OR, 51.6; P=.0004, respectively). The sensitivity, specificity, and positive and negative predictive values of plasma CMV loads were 0.47, 0.86, 0.36, and 0.91, respectively, for progression and 0.59, 0.81, 0.07, and 0.99, respectively, for resistance; those of leukocyte CMV loads were 0.52, 0.83, 0.35, and 0.91, respectively, for progression and 0.82, 0.78, 0.08, and 0.99, respectively, for resistance. A detectable plasma CMV load at the time of diagnosis of CMV retinitis was associated with mortality (median survival time, 13.6 vs. 29.7 months; P=.007).CONCLUSIONS. CMV load has limited clinical utility, because of its low positive predictive value. Its high negative predictive value for occurrence of resistant CMV suggests that it may have utility as a screening tool to exclude resistance.     

丙型肝炎患者IL28B基因型和HCV基因型对抗病毒治疗的影响

目的:研究丙型肝炎患者IL28B基因相关的rs12979860基因型和HCV基因型对聚乙二醇干扰素α和利巴韦林联合抗病毒治疗疗效的影响.方法:对干扰素α联合利巴韦林治疗后获得持续病毒学应答(SVR)和无应答(NR)的各30例丙型肝炎患者的血液样品样进行检测,采用PCR反向斑点杂交法进行HCV基因分型,采用聚合酶链-连接...     

Lack of antibodies against the antigen domain 2 epitope of cytomegalovirus (CMV) glycoprotein B is associated with CMV disease after renal transplantation in recipients having the same glycoprotein H serotypes as their donors

K. Ishibashi T. Tokumoto, H. Shirakawa, K. Hashimoto, K. Ikuta, N. Kushida, T. Yanagida, K. Shishido, K. Aikawa, H. Toma, N. Inoue, O. Yamaguchi, K. Tanabe, T. Suzutani. Lack of antibodies against the antigen domain 2 epitope of cytomegalovirus (CMV) glycoprotein B is associated with CMV disease after renal transplantation in recipients having the same glycoprotein H serotypes as their donors.
Transpl Infect Dis 2011: 13: 318–323. All rights reserved Abstract: Cytomegalovirus (CMV) reinfection of seropositive individuals has been associated with adverse outcomes in organ transplantation and is a frequent cause of congenital infection. Previously we demonstrated that mismatching of CMV glycoprotein H (gH) serotypes was associated with CMV disease after renal transplantation. Because the antigen domain 2 (AD2) epitope of glycoprotein B (gB) is conserved among CMV isolates and is one of the known targets of neutralizing antibodies, in this study we investigated whether antibodies against the epitope contribute to protection from CMV reinfection in renal transplantation, irrespective of gH serological matching. For this purpose, the gB and gH serology and clinical outcomes were analyzed retrospectively for 77 transplant recipients in the donor positive/recipient positive setting, who were managed by preemptive strategy. We found that there was a good negative correlation between the numbers of antigenemia‐positive cells and the levels of antibodies against gB AD2 in the CMV‐gH antibody matched group, but not in the CMV‐gH antibody mismatched group. None of the recipients with antibodies against both gB AD2 and strain‐specific epitopes of gH have experienced CMV disease during 6 month after transplantation, while 28% of those who lacked either/both antibody response needed preemptive therapy. Because the outcome was statistically significant, antibodies against gB AD2 can be a useful indicator to predict emergence of CMV disease for preemptive therapy, in addition to antibodies against the mismatched gH types.     

Cytomegalovirus (CMV) polymerase chain reaction profiles in individuals with advanced human immunodeficiency virus infection: relationship to CMV disease

Cytomegalovirus (CMV) disease is a common complication of patients with advanced human immunodeficiency virus infection. The aim of the present study, based on a case-cohort design, was to determine the predictive value of follow-up and baseline qualitative plasma CMV polymerase chain reaction (PCR) values for CMV end-organ disease in 378 patients (158 who progressed to CMV end-organ disease and 220 who did not develop CMV disease). These patients are part of the full AIDS Clinical Trials Group 204 multinational study (1227 patients), a randomized, controlled trial that compared the effects of valacyclovir with those of acyclovir for CMV disease prevention. Baseline PCR positivity was a significant risk factor for CMV disease progression (relative risk [RR], 1.81; 95% confidence interval [CI], 1.09-3.00). In multivariate analyses, time-updated PCR positivity was strongly associated with progression to CMV end-organ disease (RR, 4.42; 95% CI, 2.87-6.81). Change in cumulative PCR status was informative for the risk of subsequent CMV disease.     

Hepatitis B genotypes and the response to interferon therapy

BACKGROUND/AIMS: Possible pathogenic differences among hepatitis B virus (HBV) genotypes have been observed; however, the response to interferon therapy among HBV genotypes remains unknown. We therefore analyzed the efficacy of interferon alfa in the treatment of chronic hepatitis B patients with different HBV genotypes. METHODS: Fifty-eight genotype B or C infected chronic hepatitis B patients who had been treated with interferon alfa-2b were retrospectively studied. The response to interferon was defined as normalization of serum aminotransferase level, loss of hepatitis B e antigen and HBV DNA 48 weeks post-treatment. RESULTS: Baseline data of both groups of patients were comparable; however, genotype C patients had a higher serum aminotransferase level and a higher frequency of core promoter mutation. The response rate was 41% and 15% in genotype B and C patients, respectively (p=0.045). In those with higher serum aminotransferase levels, the response rate was 50% and 17%, respectively (p=0.025). Additionally, younger age and genotype B infection may predict a better response to interferon alfa. CONCLUSIONS: HBV genotype C, compared to genotype B, is associated with a higher frequency of core promoter mutation, and a lower response rate to interferon alfa therapy.     

Cytomegalovirus (CMV) resistance in patients with CMV retinitis and AIDS treated with oral or intravenous ganciclovir

Treatment of cytomegalovirus (CMV) retinitis with oral ganciclovir results in relatively low plasma concentrations of drug, which theoretically could cause more frequent viral resistance compared with intravenous (iv) ganciclovir. By use of a plaque-reduction assay to quantify phenotypic sensitivity to ganciclovir, virus isolates were studied from patients with CMV retinitis participating in four clinical trials of oral ganciclovir. Before treatment, 69% of patients were culture-positive but just 1.1% of patients yielded a resistant CMV, defined as a median inhibitory concentration (IC50) >6 microM. On treatment, the first resistant isolate was recovered at 50 days. Overall, 3.1% of patients receiving iv ganciclovir and 6. 5% of those taking oral ganciclovir shed resistant CMV (median ganciclovir exposures of 75 and 165 days, respectively). Since IC50s for clinical isolates increased proportionately with treatment duration, it is likely that viral resistance would be more frequent with longer treatment.     

Hepatitis B virus genotypes and the response to lamivudine therapy

Hepatitis B virus (HBV) can be classified into eight major genotypes (A-H) that have mainly a geographic distribution. The HBV genotype may influence disease progression, HBeAg seroconversion rates, response to antiviral treatment. The aim of study was to analyze the distribution and frequency of genotypes in patients with chronic hepatitis B. Response to lamivudine 100 mg daily therapy was examined in respect to genotype. Sixty six patients (45 (68,2%) male, 21 (31,8%) female) with chronic hepatits B were enrolled. HBV genotypes were assigned before treatment with INNO-LiPA HBV Genotyping, Innogenetics, N. V., Ghent assay, which is a line probe test based on the reverse hybridization principle. In baseline and after 12 months of treatment serological markers of HBV infection, alanine aminotransferase (ALT) activities and HBV DNA serum levels were tested. Patients with chronic hepatitis B were infected predominantly with genotype A. HBV genotype distribution was: 78,8% for genotype A, 13,6% for genotype D, 1,5% for mixed infection with genotypes A and D. Distribution of genotypes A and D was asymmetrically regardless of sex, HBeAg status, ALT and HBV DNA levels. Four (6,1%) specimens had indeterminate A results by LiPA. There were no significant differences between patients with genotypes A and D regarding age and sex. There were also no significant differences between these two groups regarding rates of HBeAg and anti-HBe positivity, ALT activity and viral load. Twenty months of lamivudine (100 mg daily) therapy resulted in significant decreases in serum HBV DNA and ALT activities in patients with genotype A as well as with genotype D. After 12 months of treatment there were no statistical differences in HBeAg seroconversion rates, ALT activities, viral loads, frequency of HBeAg and anti-HBe between genotypes A and D.     

Distinct genotypic distribution of cytomegalovirus (CMV) envelope glycoprotein B (gB) in a Cuban cohort of patients with different CMV diseases

To investigate the association between human CMV glycoprotein B (gB) genotypes and CMV disease, we retrospectively analysed 73 biological samples from 56 Cuban patients with different CMV-related diseases using a multiplex nested PCR for detection of the reported 5 CMV gB genotypes. All 4 main genotypes 1 to 4 were found in the clinical samples while no genotype 5 was detected. Among the individuals analysed, genotype gB-2 was the most prevalent (38%) followed by gB-1 (30%) and mixed infections (16%) being mainly detected among immunosuppressed patients (7 out of 9), although there was no association between mixed infections and CMV rejection in transplant recipients. Genotype gB-4 was the least frequent (5 patients), which was almost exclusively detected in mixed infections (4 out of 5, p<0.0001). Genotype gB-1 was more frequently detected in AIDS patients (47%) although it was not statistically significant, while 68% of transplant patients showed mixed infections (p<0.05). This study represents the first report of human CMV gB genotypes in Cuban patients; however, the study is limited by the small number patients, thus making it difficult to draw firm conclusions about the distribution of CMV genotypes in Cuba. Nevertheless, this preliminary report has allowed us to identify that the main 4 CMV genotypes are present in the Cuban population, with genotypes 2 and 1 being the most frequent strains.     

Discordant phenotypes and genotypes of cytomegalovirus (CMV) in patients with AIDS and relapsing CMV retinitis

OBJECTIVE: To investigate the correlation between genotypic studies performed on blood leukocytes and phenotypic results obtained from the corresponding blood viral isolates in AIDS patients with relapsing cytomegalovirus (CMV) retinitis. METHODS: Sequential blood samples were collected from patients failing intravenous or oral ganciclovir therapy. The CMV UL97 gene was amplified directly from leukocyte DNA extracts for assessing the presence of viral mutations using restriction fragment length polymorphism analysis and direct sequencing. Positive viral cultures from the same blood samples were also analyzed for their susceptibility to ganciclovir and their UL97 genotype was determined. RESULTS: Discordant CMV genotypes between the clinical specimen and the viral culture were found in at least one blood sample from three of the four patients with relapsing CMV retinitis. Furthermore, some UL97 mutations at known resistance codons (592, 594) were associated with a drug-susceptible phenotype. In all four cases, genotypic analyses of blood samples better correlated with clinical progression than phenotypic analyses of viral cultures. CONCLUSIONS: The presence of mixed viral populations in blood samples of AIDS patients and the potential selection bias introduced by susceptibility testing may underestimate the real impact of CMV resistance in patients failing antiviral therapy.     

Cytomegalovirus (CMV)-specific CD4+ T lymphocyte immune function in long-term survivors of AIDS-related CMV end-organ disease who are receiving potent antiretroviral therapy

To better understand the relation of cytomegalovirus (CMV)-specific CD4+ T lymphocyte immunity and clinical outcome in AIDS-related CMV end-organ disease, 2 patient groups were prospectively studied: patients recently diagnosed with active CMV end-organ disease and survivors of CMV retinitis who had responded to highly active antiretroviral therapy and had quiescent retinitis when anti-CMV therapy was discontinued. Most patients with active CMV disease had negative CMV-specific CD4+ T lymphocyte responses at diagnosis, as measured by lymphoproliferation (7/7) or cytokine flow cytometry (3/5) assays. In contrast, all 10 subjects with quiescent retinitis and >150 absolute CD4+ T lymphocytes/microL whose anti-CMV therapy was discontinued during 6 months of follow-up had positive CMV-specific immune responses at least once by each assay. However, 6 of these 10 subjects also had negative CMV-specific immune responses > or =1 time. Such patients may be at risk for future CMV disease progression and should be closely monitored.     

Cytomegalovirus (CMV)-specific intravenous immunoglobulin for the prevention of primary CMV infection and disease after marrow transplant.

Cytomegalovirus (CMV)-specific immunoglobulin (IVIG) was evaluated in a randomized controlled trial in CMV-seronegative marrow transplant patients with seropositive marrow donors for the prevention of primary CMV infection during the first 100 days after transplant. Patients received 200 mg/kg CMV IVIG on days 8 and 6 before transplant, the day after transplant, weekly for the first month, and then every 2 weeks to complete 10 doses. Patients were followed with weekly CMV cultures and serologic studies and for clinical and histologic evidence of CMV disease. Sixty patients were evaluable in each group. There was significantly less CMV excretion (P = .04) and viremia (P = .01) in the treatment group. However, the incidence of CMV disease including CMV pneumonia, CMV enteritis, and CMV syndrome (fever, leukopenia, hepatitis) was not statistically different. There was also no difference in median time of onset of CMV infection or disease, median number of hospital days, or survival between the two groups.     

A canarypox vector expressing cytomegalovirus (CMV) glycoprotein B primes for antibody responses to a live attenuated CMV vaccine (Towne).

To develop a vaccine against cytomegalovirus (CMV), a canarypox virus (ALVAC) expressing CMV glycoprotein (gB) was evaluated alone or in combination with a live, attenuated CMV vaccine (Towne). Three doses of 106.5 TCID50 of ALVAC-CMV(gB) induced very low neutralizing or ELISA antibodies in most seronegative adults. However, to determine whether ALVAC-CMV(gB) could prime for antibody responses, 20 seronegative adults randomly received either 106.8 TCID50 of ALVAC-CMV(gB) or 106.8 TCID50 of ALVAC-RG, expressing the rabies glycoprotein, administered at 0 and 1 month, with all subjects receiving a dose of 103.5 pfu of the Towne vaccine at 90 days. For subjects primed with ALVAC-CMV(gB), neutralizing titers and ELISA antibodies to CMV(gB) developed sooner, were much higher, and persisted longer than for subjects primed with ALVAC-RG. All vaccines were well tolerated. These results demonstrate that ALVAC-CMV(gB) primes the immune system and suggest a combined-vaccine strategy to induce potentially protective levels of neutralizing antibodies.