Effects of antibiotic treatment and antibiotics combined with surgery treatment on the prognosis of patients with infective endocarditis / 中华传染病杂志

Objective:To investigate the effects of antibiotic treatment and antibiotics combined with surgery treatment on the prognosis of patients with infective endocarditis (IE).Methods:The clinical data and prognosis of all patients diagnosed as IE discharged from Shanghai Jiao Tong University Affiliated Sixth People′s Hospital from June 2011 to May 2021 were collected. There were 240 IE patients, divided into antibiotic treatment group and the antibiotics combined with surgery group according to the treatment methods. The clinical characteristics and prognosis of the IE patients were compared between the two groups, so as to investigate the timing of surgery for IE patients and to analyze the effects of the two treatment methods on the prognosis of IE patients.Statistical analysis methods including Wilcoxon rank sum test, chi-square test, Kaplan-Meier survival analysis and Cox regression analysis were used when appropriate.Results:Of the 240 patients with IE, 63 cases were only treated with antibiotics and 177 cases were treated with antibiotics combined with surgery. After propensity score matching (PSM), one-year mortality rate of the IE patients in the antibiotics combined with surgery group was 11.1%(4/36), which was significantly lower than that in the antibiotic treatment group (33.3%(12/36), χ2=5.14, P=0.023). The median values of left ventricular ejection fraction (LVEF), left ventricular end diastolic diameter (LVEDD) and left ventricular fractional shortening (LVFS) in the antibiotics combined with surgery group were 59%, 47 mm and 31%, respectively, which were significantly lower than those before surgery (63%, 54 mm and 34%, respectively, Z=6.19, 9.36 and 6.11, respectively, all P<0.001). The most common surgical indication was moderate to severe heart failure, and there was no significant difference between the early operation group and the late operation group (both P>0.050). The one-year cumulative survival rate of antibiotics combined with surgery group was 94.9%, which was significantly higher than that in the antibiotic treatment group (83.2%, χ2=7.38, P=0.007). Heart failure and Pitt bacteremia scores≥4 were the independent risk factors for one-year all-cause death of the IE patients (hazard ratio ( HR)=5.668 and 19.392, respectively, both P<0.050). Hospital days and antibiotics combined with surgery were independent related factors for reducing the risks of one-year all-cause death ( HR=0.931 and 0.299, respectively, both P<0.050). Pitt bacteremia scores≥4 had the greatest impact on one-year prognosis of the IE patients. Conclusions:Surgery could significantly improve cardiac function and one-year prognosis of the IE patients. IE patients with heart failure and Pitt bacteremia score≥4 should be actively treated.

Effect of ubiquitination hepatitis B virus core antigen on inducing dendritic cells autophagy to enhance specific cytotoxic T lymphocyte responses / 中华传染病杂志

Objective:To clarify the effect of ubiquitination hepatitis B virus core antigen (Ub-HBcAg) on dendritic cells (DC) autophagy, and to explore the mechanism of autophagy in enhancing DC antigen presentation and inducing hepatitis B virus-specific cytotoxic T lymphocyte (CTL) responses.Methods:Ub-HBcAg lentiviral vector (LV-Ub-HBcAg), lentiviral vector-hepatitis B virus core antigen (LV-HBcAg) and no-load plasmid LV (LV) were constructed and packaged. DC2.4 cells were divided into LV-Ub-HBcAg group, LV-HBcAg group and LV group. The blank control group (NC group) was also set. The protein expression of autophagy-related protein P62, microtubule associated protein 1 light chain 3 beta (LC3B), autophagy related 5(ATG5) and Beclin-1 were detected by Western blotting. The expressions of co-stimulatory molecules such as CD86, CD80 and major histocompatibility complex (MHC)-Ⅱ were detected by flow cytometry. Cell counting kit-8 (CCK-8) method was used to detect T lymphocytes proliferation. The non-radioactive lactic acid dehydrogenase (LDH) release method was applied to detect the killing ability of CTL. Statistical analysis was conducted by independent sample t test. Results:The relative protein expressions of LC3B-Ⅱ/LC3B-Ⅰ, Beclin-1 and ATG5 in NC group were 0.445±0.076, 0.522±0.026 and 0.761±0.038, respectively, which were all lower than those in LV-Ub-HBcAg group (0.926±0.021, 0.919±0.016 and 1.451±0.028, respectively). The relative protein expression of P62 in the NC group was higher than that in LV-Ub-HBcAg group ((1.875±0.016) vs (0.647±0.121)). The differences were all statistically significant ( t=6.102, 9.842, 17.490 and 10.590, respectively, all P<0.01). The expressions of CD86 (75.51%), CD80 (83.35%), MHC-Ⅱ (66.66%) in the LV-Ub-HBcAg group were high, and those in the NC group were 8.03%, 7.49%, 0.04%, respectively. The specific CTL killing rate ((65.310±2.091)%) of the LV-Ub-HBcAg group was significantly higher than both NC group ((14.400±0.497)%) and LV-HBcAg group ((54.870±1.443)%), and the differences were both statistically significant ( t=23.690 and 4.111, respectively, both P<0.05). Conclusion:Ub-HBcAg promotes the DC autophagy, up-regulates the expressions of costimulatory molecules on cell surface of DC to induce the maturation and activation, and then stimulates T lymphocyte to induce a stronger specific CTL response under the effort of ubiquitination.

siRNA-mediated knockdown of FoxP3 promotes the ratio of T-helper 1 (Th1) to Th2 in chronic hepatitis B patients.

To determine the effect of regulatory T cells on the ratio of Th1/Th2 differentiation in peripheral blood mononuclear cells of chronic hepatitis B patients, FoxP3, the essential transcription factor for Tcells differentiation and function, was knocked down by FoxP3 siRNA, which was affirmed by real-time polymerase chain reaction for decreased expression of FoxP3. Then, at different time points, comparing with control groups, we detected enhanced lymphocyte proliferation and up-regulated Th1-type cytokines, but down-regulated Th2-type cytokines by ELISA. Finally, to research the involved mechanisms, an increased ratio of T-bet/GATA-3 mRNA expression was found by real-time polymerase chain reaction. Our results suggest that siRNA-mediated knockdown of FoxP3 could regulate the immune balance of Th1/Th2 in chronic hepatitis B patients, which may be mediated partly by regulating transcription factors T-bet and GATA-3.

The fusion protein of cytoplasmic transduction peptide (CTP)-HBcAg18-27-Tapasin enhances specific immune response to hepatitis B virus and inhibits viral replication in transgenic mice / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate the effect of protein transduction domain-hepatitis B virus core antigen (CTP-HBcAg18-27)-Tapasin fusion protein-induced specific cytotoxic T lymphocyte (CTL) response on hepatitis B virus (HBV) replication in HBV transgenic mice.</p><p><b>METHODS</b>Twenty HBV-transgenic mice were randomly divided into two groups for a 3-week course of once weekly subcutaneous immunizations with either CTP-HBcAg18-27-Tapasin fusion protein or CTP-HBcAg18-27. Mice administered isotonic saline served as blank controls. Expressions of cytokines in splenocytes were analyzed by flow cytometry. Serum levels of hepatitis B surface antigen (HBsAg) and HBV DNA were determined by microparticle enzyme immunoassay and real-time fluorescent PCR assay, respectively. Expression of HBsAg in hepatic tissues was detected by immunohistochemistry.</p><p><b>RESULTS</b>Immunization with 100 mug of CTP-HBcAg18-27-Tapasin fusion protein led to a significant increase in proportions of CTLs in spleen (2.70%+/-0.20% vs. 50 mug of CTP-HBcAg18-27-Tapasin: 1.66%+/-0.53%, 50 mug of CTP-HBcAg18-27: 1.26%+/-0.56%, and blank controls: 0.75%+/-0.71%; F = 741.45, P = 0.000) and up-regulation of inflammatory cells in hepatic tissue. In addition, both immunizations of CTP-HBcAg18-27-Tapasin led to significant decreases in serum HBsAg and HBV DNA levels compared to those in the CTP-HBcAg18-27 group.</p><p><b>CONCLUSION</b>HBV-related modification of the expression of the molecular chaperone Tapasin may affect its interaction with intracellular antigen peptides, thereby leading to increases the number of specific CTLs in the spleen, decreases in serum HBsAg and HBV DNA levels, and down-regulation of HBsAg expression in hepatic tissue. These results obtained in HBV-transgenic mice suggest that the CTP-HBcAg18-27-Tapasin fusion protein has anti-HBV activity.</p>

Effects of cytoplasmic transduction peptide-HBcAg18-27-Tapasin induced murine bone marrow derived dendritic cell maturation on T lymphocyte proliferation in vitro / 中华传染病杂志

Objective To observe the effects of cytoplasmic transduction peptide (CTP)-HBcAg18-27-Tapasin induced murine bone marrow-derived dendritic cell (DC) maturation on T lymphocyte proliferation in vitro,Methods Bone marrow derived DC isolated from BALB/c mice were cultured with recombinant granulocyte-macrophage colony-stimulating factor and recombinant interleutin (IL)-4 for 5 days followed by lipopolysaccharide added to induce DC maturation.10 μg/L CTP-HBcAg18-27-Tapasin,50 μg/L CTP-HBcAg18-27-Tapasin,10 μg/L CTP-HBcAg18-27 or RPMI-1640 were added into culture medium to induce DC maturation.DC phenotypes were analyzed by flow cytometry.The level of IL-12p70 in the supernatant was detected by enzyme linked immunosorbent assay.The proliferation of.T lymphocytes was performed by using cell counting kit-8 and intracellular cytokine of proliferative T cells were analyzed by flow cytometry.The means among groups were compared using one-way ANOVA and those between two groups were compared by least significant difference test.Results DC were cultured and induced successfully.The molecules on DC surface,such as CD80,CD86 and major histocompatibility antigen-Ⅰ were upregulated by CTP-HBcAg18-27-Tapasin.IL-12p70 level induced by 50 μg/L CTP-HBcAg18-27-Tapasin was (61.12±10.25) pg/mL,which was higher than those induced by 10 μg/L CTP-HBcAg18-27-Tapasin (50.43±10.42) pg/mL,10μg/L CTP-HBcAg18-27 (40.17±8.54) pg/mL and medium control (30.51±8.03) pg/mL (F=15.85,P=0.030 and 0.037).The proliferation of T lymphocytes induced by CTP- HBcAg18-27 -Tapasin was higher than control groups.The amounts of cytotoxic T lymphocyte (CTL) induced by 50 μg/L CTP-HBcAg18-27-Tapasin [(2.05±0.41) ％] and 10 μg/L CTP-HBcAg18-27-Tapasin [(1.06 ±0.10 )％] were both significantly higher than the 10 μg/L CTP-HBcAg18-27 group [(0.45±0.11)％] and medium group [(0.09±0.02)％,F=60.22,P=0.003].Conclusions CTP HBcAg18- 27 Tapasin could promote the differentiation and maturation of DC,and enhance the ability of DC stimulating T lymphocytes proliferation and increase CTL expression effectively.

Trans-activator of transcription protein transduction domain mediated cell membrane penetration of HBcAg / 中华传染病杂志

0bjective To observe the cell membrane penetration of protein transduction domain (PTD)-HBeAg fusion protein in vitro.Methods The sequence of trans-activator of transcription (Tat)-PTD was synthesized and the whole HBcAg gene was amplified by polymerase chain reaction (PCR).Overlap extension PCR was employed to fuse Tat-PTD and whole HBcAg gene.Then the fusion gene was cloned into prokaryotic expression vector pMAL-c2X.The correct vector was transformed into E.coli Rosetta-gamiTM 2(DE3),and the protein was induced by isopropyl β-D-1-thiogalactopyranoside(IPTG).Western blot was used tO identify the protein. Furthermore,the fusion protein PTD-HBcAg was purified by affinity chromatography.HBcAg protein expressed using the same methods was employed as eontr0l.The purified protein was added tO HuH-7 cell culture,then the transduction of PTD-HBcAg and HBcAg in cells were detected by indirect immunofluorescence assay (IFA).Results The fusion protein was effectively expressed in E. Coli and purified by affinity chromatography.Both purified PTD-HBcAg and HBcAg could be recognized by HBeAg monoclonal antibody in Western blot analysis.IFA visualization showed that PTD-HBeAg could be introduced into HUH-7 ceils while HBcAg only could not be detected in cells.Conclusions PTD-HBcAg fusion protein can be expressed effectively and purified in prokaryotic expression system.PTD could mediate HBcAg penetrating eell membrane into the cells.

A mouse model of congenital human cytomegalovirus infection that induces liver damage in fetus / 中华传染病杂志

Objective To define that human cytomegalovirus (HCMV) can cross the placenta of the Balb/c mice and induce liver damage in developing fetus. Methods HCMV AD169 (6.0 logTCID 50 , 3.0 logTCID 50 , 1.5 logTCID 50 per mouse respectively) was injected into the peritoneum of mice (half of mice were female) when they were about 10 weeks old (weight 25 30g). Then, these mice were paired to mate. Fetus on day about to give birth was removed from the uterus and liver was obtained for virus isolation, pathological studies, examination of the viral DNA positive cells by in situ hybridization using digoxigenin labelled HCMV DNA oligonucleotide probe. Results HCMV could be isolated from the supernatant of tissues; HCMV DNA was found by PCR in supernatant of cell culture with CPE; the presence of viral DNA sequence in hepatocytes was confirmed by in situ hybridization; pathological changes in liver consist of swollen cytoplasm and destroyed nuclei of hepatocytes and distinct intranuclear inclusion in hepatocytes with a cellular infiltrates of predominantly phagocytic cells. All above were found more obviously in fetal mouse liver tissues from the group inoculated with 6.0 log TCID 50 HCMV AD169 as compared with 3.0 log TCID 50 group. In contrast, these positive results couldn't be well found in 1.5 log TCID 50 group. Nothing could be found in normal controls. Conclusions Our research suggests that primary maternal HCMV infection during pregnancy could induce congenital infection in fetus by transplacental transmission and induce fetal liver damage. The mouse model will provide the basis for the study on pathogenesis of congenital HCMV infection in liver and the development of prevention, diagnosis and antiviral agents for congenital HCMV infection in human being.

Construction of a phage display library of human single-chain Fv antibodies from peripheral blood lymphocytes of people with positive serum antibody against hepatitis B virus core protein / 中华传染病杂志

Objective To construcr a phage display library of human single-chain Fv antibodies from peripheral blood lymphocytes of people with positive serum antibody against hepatitis B virus core protein. Methods The heavy chain and light chain variable region gene of human immunoglobulin were amplified individually by RT-PCR from peripheral blood Lymphocytes mRNA of patients with positive serum hepatitis B virus core protein antibody and randomly combined through a DNA linker encoding the peptide (Gly 4Ser) 3 to construct single-chain variable fragments (ScFv)gene. In the presence of helper phage M13KO7, the ScFv were displayed on the surface of recombinant phages. Results Repertoire antibody library was obtained with 10 6 clonies resistant to ampicillin and kanamycin. Conclusions A typical phage display library of human single-chain Fv antibodies has been constructed Using RT-polymerase chain reaction (RT-PCR) and phage display technique, human single-chain Fv antibodies can be screened from this library.

Screening,identifying and sequencing of human single-chain variable fragment specific to hepatitis B virus core protein / 中国病理生理杂志

AIM: To Screen and identify human single-chain variable fragment (ScFv) specific to hepatitis B virus core protein and determine its gene sequence. METHODS: The recombinant phages were panned by HBcAg coated in a 96-pore plate and 48 clones were identified specific to HBc after three rounds of panning. The specificity of ScFv from the positive clone was determined by ELISA. Then, the soluble ScFv was expressed in E.coli. HB2151 and secreted in the supernatant. Subsequently, SDS-PAGE and dot blot were performed to identify the ScFv in the supernatant and cell lysate. The gene of ScFv specific to hepatitis B virus core protein was sequenced. RESULTS: The ScFv screened from phage antibodies has a specific combination character with hepatitis B virus core antigen. Soluble ScFv was confirmed to express in E.coli. HB2151 and secrete in the supernatant. The sequence of ScFv gene conformed to that of heavy chain and kappa chain of human immunoglubulin. CONCLUSION: Human ScFv specific to hepatitis B virus core protein has been identified by means of the phage display technology, and its gene sequence has been determined.

CD_(25) Expression in Peripheral Blood T Lymphocytes from Patients with Chronic Hepatitis B and Its Significance / 中华医院感染学杂志

OBJECTIVE To investigate CD25 expression in peripheral blood T lymphocytes from patients with chronic hepatitis B,and explore its significance in the pathogenesis of chronic hepatitis B.METHODS To detect CD25 expression in peripheral blood T lymphocytes of patients with chronic hepatitis B by means of flow cytometry.CD25 expression was observed in chronic hepatitis B patients.In the meantime,CD25 expression in T cells from severe chronic hepatitis or acute hepatitis B patients and asymptomatic carriers of HBV was also observed.RESULTS Varying degrees of CD25 were expressed in T cells from hepatitis B patients.The expression in CD3+ T and CD8+T cells was higher than that in CD4+T cells.CD25 expression in CD4+T was lower.The average of CD25 expression in CD3+T cells from patients with chronic hepatitis B,acute hepatitis B,and chronic severe hepatitis B and asymptomatic carriers of HBV was(2.92?0.13)%,(0.51?0.36)%,(1.60?0.07)%,and(0.95?0.23)%,respectively.The average of CD25 expression in CD4+T cells from patients with chronic hepatitis B,acute hepatitis B and chronic severe hepatitis B and asymptomatic carriers of HBV was(2.58?0.50)%,(0.34?0.07)%,(1.45?0.02)%,and(0.83?0.13)%,respectively.CD3+T and CD4+T CD25 expression in patients with chronic hepatitis and,severe chronic hepatitis B was increased compared with that of acute hepatitis B patients and asymptomatic carriers of HBV.Compared with chronic severe hepatitis B,the expression of chronic hepatitis B was higher.CONCLUSIONS CD4+ CD25+T cells in chronic hepatitis B virus infection are increased compared with acute hepatitis,CD4+ CD25+T cells may be related to immune tolerance.

Construction of human anti-HBc ScFv eukaryotic expression vector and expression of anti-HBc ScFv in HepG2 cells / 中国病理生理杂志

AIM: To construct an eukaryotic expression vector of human single-chain variable fragment ~against hepatitis B virus core protein (anti-HBc ScFv) and detect its expression in HepG2 cells. METHODS: Anti-HBc ScFv genes were amplified from the plasmids abstracted from positive clone and inserted into pEGFP-c1 vector that contained green fluorescent protein gene. The recombinant plasmids were transfected into HepG2 cells, and resistant clones were obtained by G418 selection. The expression of the gene of fusion protein was determined by fluorescent invert microscope and ELISA. RESULTS: Recombinant plasmids were successfully constructed. The plasmid transfected HepG2 cells were obtained by G418 selection. Specific fluorescence was observed in HepG2 cells 48 hours after transfection. ELISA analysis confirmed the expression of anti-HBc ScFv in the cells. CONCLUSION: The construction of human anti-HBc ScFv eukaryotic expression vector and its expression in HepG2 cells lay the foundation for advanced research of intracellular anti-HBc ScFv.