ABSTRACT
Background The proliferation and migration of vascular endothelial cells is a primary link during angiogenesis.Studies showed that heat shock protein B6 (HspB6) promotes the secretion of multiple angiogenesis-related factors and therefore leads to neovascularization.Understanding the effects of neutralizing HspB6 antibody on the biological behavior of human choroidal vascular endothelial cells has an important significance in the target treatment of choroidal neovacularization diseases.Objective This study was to address the role and mechanism of neutralizing HspB6 antibody in tube formation of human choroidal vascular endothelial cells.Methods Human choroidal vascular endothelial cell line was normally cultured and harvested for total RNA extraction.Expressions of HspB6 mRNA and protein in human choroidal vascular endothelial cells were detected by reverse transcription PCR (RT-PCR) and flow cytometry (FCM).The cells were seeded on 96-well plate covered with matrigel at the density of 2×104/hole.Then the neutralizing HspB6 antibody at the concentration of 100 μg/Land 500 μg/L was added into the medium respectively,and the control cells were set without the addition of HspB6 antibody.The number of capillary tubes was calculated 12 hours after culture by three-dimensional matrigel assay.In addition,0,50,100,500 μg/L of neutralizing HspB6 antibody were added into the cell medium separately for 24hours,cell counting kit-8 (CCK-8) method was employed to assay the inhibitory rate(IR) of the cells.Transwell test was used to count the cell number across chamber membrane for the evaluation of migration ability of the cells.The apoptosis of the cells was assayed by FCM.Results Both HspB6 mRNA and protein were expressed on human choroidal vascular endothelial cells.The number of capillary tube formation of human choroidal vascular endothelial cells was (67.25±5.75),(60.39±6.41) and (39.76±10.73) /field in the 0,100 and 500 μg/L neutralizing HspB6 antibody groups,with significant difference among them (F =10.210,P =0.012),and the tube number was significantly less in the 500 μg/L neutralizing HspB6 antibody group compared with 0 μg/L neutralizing HspB6 group (P =0.005).The IR of neutralizing HspB6 antibody to the cellular proliferation and migration was enhanced with the increases of concentration and time lapse(Fconcentration =7.485,P =0.002 ; Ftime =16.684,P =0.001).The number of the cells through Transwell chamber membrane was 14.0 ± 2.5,11.1 ± 0.8,6.6 ± 0.1,6.7 ± 0.2 in the 0,50,100,500 μg/L neutralizing HspB6 antibody group respectively,and that in the 100 μg/L and 500 μg/L neutralizing HspB6 antibody group was lessened in comparison with the 0 μg/L neutralizing HspB6 antibody group(both at P=0.000).The apoptosis rate of the cells was (22.73 ± 2.53)％ in the neutralizing HspB6 antibody group,which was significantly lower than (13.33±2.08) ％ of the control group (t=4.967,P=0.008).Conclusions Neutralizing HspB6 antibody inhibits capillary tube formation of human choroidal endothelial cells in vitro in dose-and timedependent manner,probably through suppressing the proliferation and migration and promoting the apoptosis of choroidal endothelial cells.
ABSTRACT
<p><b>OBJECTIVE</b>To study the resistant rate of hepatitis B virus (HBV) to ADV and the dynamic evolution of HBV in lamivudine (Lam)-resistant chronic hepatitis B (CHB) patients.</p><p><b>METHODS</b>Twenty-three Lam-resistant CHB patients were assigned to a 10mg/d ADV monotherapy for 68-116 weeks. The baseline and different time point blood samples after ADV monotherapy were analyzed for ADV-resistant mutations using direct sequencing of PCR products; the evolution of HBV mutations was examined by clonal analysis of serial samples from one patient infected with ADV-associated resistant HBV strains.</p><p><b>RESULTS</b>The cumulative incidence of genotypic ADV resistance at weeks 48 and 96 was 4.3% and 10.5% respectively respectively. The evolution analysis of HBV mutant strains in an ADV-resistant CHB patient showed that the proportion of YMDD mutants gradually decreased with rtA181S mutants increasing over time after ADV monotherapy, and that rtA181S+N236T mutants became the predominant strains during prolonged ADV monotherapy. The addition of Lam to the ongoing ADV treatment had poorer antiviral response in the patient with rtA181S or rtA181S+N236T mutant infection; one clone with multi-drug resistant mutations was selected during Lam and ADV combination therapy.</p><p><b>CONCLUSION</b>Increased risk of adefovir resistance and selection of multi-drug resistant mutations are associated with long-term ADV monotherapy in patients with Lam-resistant chronic hepatitis B.</p>
Subject(s)
Adult , Female , Humans , Male , Middle Aged , Adenine , Therapeutic Uses , Antiviral Agents , Therapeutic Uses , Drug Resistance, Viral , Evolution, Molecular , Hepatitis B virus , Classification , Genetics , Hepatitis B, Chronic , Drug Therapy , Virology , Lamivudine , Pharmacology , Organophosphonates , Therapeutic UsesABSTRACT
Objective To establish a convenient,accurate and practical method for detection of adefovir dipivoxil resistance-as- sociated mutation in hepatitis B virus:rtA181V/T/S and rtN236T mutations.Methods According to HBV complete sequences in GenBank,two pairs of primers were designed to amplify the region of HBV reverse transcriptase in order to introduce a BglI restriction site upon PCR product of wild type (wt) and a BseDI restriction site upon PCR product of rt236 mutant type.After amplification,the PCR products were digested with BglI and BseDI separately.We used this method to detect wild,rt181 mu- tant,rt236 mutant plasmids and 3 chronic hepatitis B patients' serum with obvious ADV resistance-associated mutations.We also tested the sensitivity of this method by mixing the wild and mutant plasmids in different proportions.Results The method could detect rt181 and rt236 mutations simultaneously.The result of RFLP analysis was in accordance with that of DNA se- quencing and cloning analysis.This method could detect the mutants even when they comprised only 10% of the total virus population.Conclusions The PCR-RFLP method with high sensitivity can detect rt181 and rt236 mutations simultaneously.It can be used for early detection of ADV resistance-associated mutation in hepatitis B virus.