Etiological and epidemiological features of acute meningitis or encephalitis in China: a nationwide active surveillance study.

BACKGROUND: Acute meningitis or encephalitis (AME) results from a neurological infection causing high case fatality and severe sequelae. AME lacked comprehensive surveillance in China. METHODS: Nation-wide surveillance of all-age patients with AME syndromes was conducted in 144 sentinel hospitals of 29 provinces in China. Eleven AME-causative viral and bacterial pathogens were tested with multiple diagnostic methods. FINDINGS: Between 2009 and 2018, 20,454 AME patients were recruited for tests. Based on 9,079 patients with all-four-virus tested, 28.43% (95% CI: 27.50%‒29.36%) of them had at least one virus-positive detection. Enterovirus was the most frequently determined virus in children <18 years, herpes simplex virus and Japanese encephalitis virus were the most frequently determined in 18-59 and ≥60 years age groups, respectively. Based on 6,802 patients with all-seven-bacteria tested, 4.43% (95% CI: 3.94%‒4.91%) had at least one bacteria-positive detection, Streptococcus pneumoniae and Neisseria meningitidis were the leading bacterium in children aged <5 years and 5-17 years, respectively. Staphylococcus aureus was the most frequently detected in adults aged 18-59 and ≥60 years. The pathogen spectrum also differed statistically significantly between northern and southern China. Joinpoint analysis revealed age-specific positive rates, with enterovirus, herpes simplex virus and mumps virus peaking at 3-6 years old, while Japanese encephalitis virus peaked in the ≥60 years old. As age increased, the positive rate for Streptococcus pneumoniae and Escherichia coli statistically significantly decreased, while for Staphylococcus aureus and Streptococcus suis it increased. INTERPRETATION: The current findings allow enhanced identification of the predominant AME-related pathogen candidates for diagnosis in clinical practice and more targeted application of prevention and control measures in China, and a possible reassessment of vaccination strategy. FUNDING: China Mega-Project on Infectious Disease Prevention and the National Natural Science Funds.

Etiological and epidemiological features of acute respiratory infections in China.

Nationwide prospective surveillance of all-age patients with acute respiratory infections was conducted in China between 2009‒2019. Here we report the etiological and epidemiological features of the 231,107 eligible patients enrolled in this analysis. Children <5 years old and school-age children have the highest viral positivity rate (46.9%) and bacterial positivity rate (30.9%). Influenza virus, respiratory syncytial virus and human rhinovirus are the three leading viral pathogens with proportions of 28.5%, 16.8% and 16.7%, and Streptococcus pneumoniae, Mycoplasma pneumoniae and Klebsiella pneumoniae are the three leading bacterial pathogens (29.9%, 18.6% and 15.8%). Negative interactions between viruses and positive interactions between viral and bacterial pathogens are common. A Join-Point analysis reveals the age-specific positivity rate and how this varied for individual pathogens. These data indicate that differential priorities for diagnosis, prevention and control should be highlighted in terms of acute respiratory tract infection patients' demography, geographic locations and season of illness in China.

Etiological, epidemiological, and clinical features of acute diarrhea in China.

National-based prospective surveillance of all-age patients with acute diarrhea was conducted in China between 2009‒2018. Here we report the etiological, epidemiological, and clinical features of the 152,792 eligible patients enrolled in this analysis. Rotavirus A and norovirus are the two leading viral pathogens detected in the patients, followed by adenovirus and astrovirus. Diarrheagenic Escherichia coli and nontyphoidal Salmonella are the two leading bacterial pathogens, followed by Shigella and Vibrio parahaemolyticus. Patients aged <5 years had higher overall positive rate of viral pathogens, while bacterial pathogens were more common in patients aged 18‒45 years. A joinpoint analysis revealed the age-specific positivity rate and how this varied for individual pathogens. Our findings fill crucial gaps of how the distributions of enteropathogens change across China in patients with diarrhea. This allows enhanced identification of the predominant diarrheal pathogen candidates for diagnosis in clinical practice and more targeted application of prevention and control measures.

Serum dihydroxyacetone kinase peptide m/z 520.3 as predictor of disease severity in patients with compensated chronic hepatitis B.

BACKGROUND AND AIM: Due to known limitations of liver biopsy, reliable non-invasive serum biomarkers for chronic liver diseases are needed. We performed serum peptidomics for such investigation in compensated chronic hepatitis B (CHB) patients. METHODS: Liquid chromatography combined with tandem mass spectrometry (LC-MS/MS) was used to identify differentially expressed peptides in sera from 40 CHB patients (20 with S0G0-S1G1 and 20 with S3G3-S4G4). Ion pair quantification from differentially expressed peptides in a validation set of sera from 86 CHB patients was done with multiple reaction monitoring (MRM). RESULTS: 21 differentially represented peptide peaks were found through LC-MS/MS. Ion pairs generated from eleven of these peptides (m/z < 800) were quantified by MRM. Summed peak area ratios of 6 ion pairs from peptide m/z 520.3 (176.1, 353.7, 459.8, 503.3, 351.3, 593.1), which was identified as dihydroxyacetone kinase (DAK) fragment, decreased from mild to advanced stages of fibrosis or inflammation. Area Under Receiver Operating Characteristic Curves (AUROCs) of five ion models discriminating fibrosis degrees were 0.871 ~ 0.915 (S2-4 versus S0-1) and 0.804 ~ 0.924 (S3-4 versus S0-2). AUROCs discriminating inflammation grades were 0.840 ~ 0.902 (G2-4 versus G0-1) and 0.787 ~ 0.888 (G3-4 versus G0-2). The diagnostic power of these models provides improved sensitivity and specificity for predicting disease progression as compared to aspartate aminotransferase to platelet ratio index (APRI), FIB-4, Forn's index and serum DAK protein. CONCLUSIONS: The peptide fragment (m/z 520.3) of DAK is a promising biomarker to guide timing of antiviral treatment and to avoid liver biopsy in compensated CHB patients.

Tetrazole and triazole as bioisosteres of carboxylic acid: discovery of diketo tetrazoles and diketo triazoles as anti-HCV agents.

A series of diketo tetrazoles and diketo triazoles were designed and synthesized as bioisosteres of α,γ-diketo acid, the active site inhibitor of HCV (Hepatitis C virus) polymerase NS5B. Among the synthesized compounds, 4-(4-fluorobenzyloxy)phenyl diketo triazole (30) exhibited anti-HCV activity with an EC50 value of 3.9 µM and an SI value more than 128. The reduction of viral protein and mRNA levels were also validated, supporting the anti-HCV activity of compound 30. These results provide convincing evidence that the diketo tetrazoles and diketo triazoles can be developed as bioisosteres of α,γ-diketo acid to exhibit potent inhibitory activity against HCV.

Results of a phase III clinical trial with an HBsAg-HBIG immunogenic complex therapeutic vaccine for chronic hepatitis B patients: experiences and findings.

BACKGROUND & AIMS: Even though various experimental therapeutic approaches for chronic hepatitis B infection have been reported, few of them have been verified by clinical trials. We have developed an antigen-antibody (HBsAg-HBIG) immunogenic complex therapeutic vaccine candidate with alum as adjuvant (YIC), aimed at breaking immune tolerance to HBV by modulating viral antigen processing and presentation. A double-blind, placebo-controlled, phase II B clinical trial of YIC has been reported previously, and herein we present the results of the phase III clinical trial of 450 patients. METHODS: Twelve doses of either YIC or alum alone as placebo were administered randomly to 450 CHB patients and they were followed for 24weeks after the completion of immunization. The primary end point was HBeAg seroconversion, and the secondary end points were decrease in viral load, improvement of liver function, and histology. RESULTS: In contrast to the previous phase II B trial using six doses of YIC and alum as placebo, six more injections of YIC or alum resulted in a decrease of the HBeAg seroconversion rate from 21.8% to 14.0% in the YIC group, but an increase from 9% to 21.9% in the alum group. Decrease in serum HBV DNA and normalization of liver function were similar in both groups (p>0.05). CONCLUSIONS: Overstimulation with YIC did not increase but decreased its efficacy due to immune fatigue in hosts. An appropriate immunization protocol should be explored and is crucial for therapeutic vaccination. Multiple injections of alum alone could have stimulated potent inflammatory and innate immune responses contributing to its therapeutic efficacy, and needs further investigation.

[The emergence of novel GII.4 norovirus variant, Sydney_2012, in Shanghai, China].

To describe the epidemiological characteristics of norovirus (NOV) associated acute gastroenteritis in Shanghai and characterize the evolution pattern of circulating strains. From March 2012 to February 2013, 502 stool specimens were collected from adult (> or = 16 years) outpatients who visited either of the two sentinel hospitals in Shanghai for acute gastroenteritis. Molecular detection and genotyping of NoV were performed and the phylogenetic relationship of the circulating strains has also been comprehensively analyzed. The epidemics level of GI NoV was low throughout the surveillance period, with the positive rate of 3.78% (19 cases), and no seasonality of GI NoV infection could be distinguished. For GII genogroup, higher epidemics in adults in Shanghai, with the detection rate of 17.13% (86 cases), were observed. And relatively high epidemics of GII NoV infection were spotted between October and December in 2012. The frequency of NoV associated acute gastroenteritis in older people is significantly higher than that in young individuals (P < 0.05). Sequencing and genotyping analysis revealed that the high epidemics of GII NoV infection between October and December in 2012 is associated with the emergence of a novel GII.4 norovirus strain, termed Sydney_2012. Sequence analysis also demonstrated that this was a recombinant virus between a GII.e polymerase and GII.4 capsid, which has also been the dominant circulating strain in Shanghai. In 2012, a new GII.4 variant, termed Sydney_2012, emerged in Shanghai and caused high epidemics of acute gastroenteritis during late autumn and winter.

[Plasma proteome analysis of chronic hepatitis B patients with different stages of liver fibrosis].

OBJECTIVE: To identify plasma biomarkers with specific relation to the various liver fibrosis stages that can be used to assess hepatitis B virus (HBV)-infected patients for non-invasive liver fibrosis and to evaluate the prognosis of the liver fibrosis. METHODS: Plasma samples were collected from 80 HBV-positive patients at the Hepatitis Department of Shanghai Public Health Clinical Center between September 2008 and January 2011. The samples were grouped according to the patient's stage of hepatic fibrosis determined by liver biopsy: S0-1 (n = 40), S2-3 (n = 20), and S4 (n = 20). Each plasma sample was processed to remove the two most abundant proteins, albumin and immunoglobulin G (IgG), and then resolved by two-dimensional (2D) electrophoresis. ImageMaster 2D analysis software was used to identify differentially expressed proteins related to the liver fibrosis stages. After trypsin digestion, the differential proteins were identified by online reversed-phase nano-flow liquid chromatography coupled with electrospray ionization ion trap mass spectrometry (MS). RESULTS: The patients in the three groups were not significantly different in age (range: 30-50 years; P = 0.053) or sex (x² = 0.155, P = 0.926). Low-abundance proteins were efficiently enriched by the albumin/IgG depletion method. Fourteen differentially expressed proteins were detected among the S0-1, S2-3 and S4 groups, all of which were identified by tandem MS and included fibrinogen gamma chain, haptoglobin, complement C3, Ig kappa chain C region, and apolipoprotein A-I. CONCLUSION: Plasma proteomic analysis of chronic hepatitis B patients identified a panel of differentially expressed proteins related to different stages of liver fibrosis. These proteins may represent diagnostic and prognostic biomarkers of HBV-related hepatic fibrosis.

DNA-dependent activator of interferon-regulatory factors inhibits hepatitis B virus replication.

AIM: To investigate whether DNA-dependent activator of interferon-regulatory factors (DAI) inhibits hepatitis B virus (HBV) replication and what the mechanism is. METHODS: After the human hepatoma cell line Huh7 was cotransfected with DAI and HBV expressing plasmid, viral protein (HBV surface antigen and HBV e antigen) secretion was detected by enzyme-linked immunosorbent assay, and HBV RNA was analyzed by real-time polymerase chain reaction and Northern blotting, and viral DNA replicative intermediates were examined by Southern blotting. Interferon regulatory factor 3 (IRF3) phosphorylation and nuclear translocation were analyzed via Western blotting and immunofluorescence staining respectively. Nuclear factor-κB (NF-κB) activity induced by DAI was detected by immunofluorescence staining of P65 and dual luciferase reporter assay. Transwell co-culture experiment was performed in order to investigate whether the antiviral effects of DAI were dependent on the secreted cytokines. RESULTS: Viral protein secretion was significantly reduced by 57% (P < 0.05), and the level of total HBV RNA was reduced by 67% (P < 0.05). The viral core particle-associated DNA was also dramatically down-regulated in DAI-expressing Huh7 cells. Analysis of involved signaling pathways revealed that activation of NF-κB signaling was essential for DAI to elicit antiviral response in Huh7 cells. When the NF-κB signaling pathway was blocked by a NF-κB signaling suppressor (IκBα-SR), the anti-HBV activity of DAI was remarkably abrogated. The inhibitory effect of DAI was independent of IRF3 signaling and secreted cytokines. CONCLUSION: This study demonstrates that DAI can inhibit HBV replication and the inhibitory effect is associated with activation of NF-κB but independent of IRF3 and secreted cytokines.

Transcriptional analysis of immune-related genes in dendritic cells from hepatitis B surface antigen (HBsAg)-positive transgenic mice and regulation of Fc gamma receptor IIB by HBsAg-anti-HBs complex.

To study the gene expression profiles in dendritic cells (DCs) from a hepatitis B surface antigen (HBsAg) positive host, transcriptional analysis of bone marrow -derived DCs from a lineage of HBsAg transgenic mice (#59) was compared to DCs from normal mice. Among the immune-related genes, 12 were up-regulated, and 14 were down-regulated in transgenic mice relative to those of normal mice. The up-regulated genes include genes encoding immunoglobulin, histocompatibility 2 (K region), and several complement component genes, while the down-regulated genes include the TAP1 (transporters associated with antigen processing gene-1), interferon induced gene (Ifi203), chemokine (C-X-C) ligands and leukocyte-immunoglobulin-like genes, Lck-interacting transmembrane adaptor genes and histocompatibility 2 (Q region and T region). Since an immunogenic complex containing HBsAg-anti-HBs has been used as a therapeutic vaccine for clinical trial in chronic hepatitis B patients, DCs from #59 were incubated with immunogenic complex compared to those incubated with HBsAg alone. The immune-related six genes up-regulated with immunogenic complex treatment were Fcgr2b, Cxcl2, Fth1, Clec4n, Lilrb4, and Dbh, with Fcgr2b (Fc gamma receptor IIB) being the highest up-regulated gene. Interestingly, levels of Fcgr2b were found up-regulated in patients with chronic hepatitis B undergoing immunogenic complex immunization, which returned to baseline when immunization was discontinued. In conclusion, by transcriptional analysis, immunogenic complex induced up-regulation of Fcgr2b expression both in dendritic cells from an HBsAg transgenic mouse model and peripheral B cells from patients with chronic hepatitis B, which indicates that Fcgr2b is one of the key molecules up-regulated by immunogenic complex.

[Subcellular proteome analysis of immune or alcohol induced rat liver fibrosis].

OBJECTIVE: To study the mechanism of liver fibrogenesis and to find new non-invasive biomarkers. METHOD: In this study, we used subcellular proteomic technology to study the plasma membrane proteins related to immune or alcohol induced liver fibrosis. Rat liver fibrosis models were induced by pig serum or alcohol injection. The liver fibrogenesis were detected by James's staining in the rat models after 2, 4, 6 and 8 weeks of treatment. The liver plasma membrane (PM) of the 2- and 8-week treatment model rats were enriched by two-step sucrose density gradient centrifugation. The purity of PM was verified by western blotting, and the plasma membrane proteins were extracted and analyzed by 2 DE. The differentially expressed proteins were identified by LC-MS/MS. Cellular location and function of these identified differential protein were classified. RESULTS: Immune or alcohol induced liver fibrosis rat models were successfully established. Liver plasma membrane was significantly enriched after sucrose density ultracentrifugation treatment. 87 differential protein spots were find out by 2DE combined with LC-MS/MS from the liver plasma membrane proteins of the 2- and 8-week treatment rat models, which corresponded to 30 non-redundant proteins including annexin A2, keratin 8 and keratin 18. CONCLUSIONS: A list of differentially expressed proteins relate to liver fibrosis were successfully identified. Differential proteins such as annexin A2, keratin 8 and keratin 18 could be new biomarkers for liver fibrosis diagnosis.

Serum HBeAg sero-conversion correlated with decrease of HBsAg and HBV DNA in chronic hepatitis B patients treated with a therapeutic vaccine.

Currently, there are various approaches for developing therapeutic vaccines for chronic hepatitis B patients. Previously, an antigen-antibody-based therapeutic vaccine (YIC) has been conducted in a double-blind placebo controlled phase IIb clinical trial in 242 chronic hepatitis B patients. At the end of follow-up for 24 weeks, HBeAg sero-conversion rate was 21.6% in the 60 µg immunized group, compared to 9% in the alum immunized control group (p=0.03). To analyze the correlation between HBeAg-seroconversion, and decrease of serum HBsAg and HBV DNA, serum samples were back quantified for serum HBsAg and HBV DNA collected at baseline, end of treatment, and end of follow-up from patients who were treated either with 60 µg of YIC, or with placebo. Patients were dichotomized to HBeAg sero-converted and non-converted groups in comparison with patients in the placebo group. The correlations between HBeAg seroconversion and the decrease of HBsAg, HBV DNA and ALT levels during study period were analyzed using a logistic regression model. Results showed marked and sustained reduction of HBsAg, HBV DNA and ALT level in HBeAg sero-converted patients compared to those in patients of HBeAg non-converted and placebo groups. Reduction of HBV DNA and elevation of ALT was markedly associated with HBeAg seroconversion with an adjusted OR of 0.09 (95%CI: 0.01-0.62) and 0.08 (95%CI: 0.02-0.37) respectively after adjusted by age and sex, while reduction of HBsAg level was close to of significance (p=0.054). Analysis indicated that HBeAg sero-conversion was a reasonable endpoint for therapeutic vaccination.

Rupintrivir is a promising candidate for treating severe cases of Enterovirus-71 infection.

AIM: To evaluate the suitability of rupintrivir against Enterovirus 71 (EV71) induced severe clinical symptoms using computational methods. METHODS: The structure of EV71 3C protease was predicted by homology modeling. The binding free energies between rupintrivir and EV71 3C and human rhinovirus 3C protease were computed by molecular dynamics and molecular mechanics Poisson-Boltzmann/surface area and molecular mechanics generalized-born/surface area methods. EV71 3C fragments obtained from clinical samples collected during May to July 2008 in Shanghai were amplified by reverse-transcription and polymerase chain reaction and sequenced. RESULTS: We observed that rupintrivir had favorable binding affinity with EV71 3C protease (-10.76 kcal/mol). The variability of the 3C protein sequence in isolates of various outbreaks, including those obtained in our hospital from May to July 2008, were also analyzed to validate the conservation of the drug binding pocket. CONCLUSION: Rupintrivir, whose safety profiles had been proved, is an attractive candidate and can be quickly utilized for treating severe EV71 infection.

Measles virus infection in adults induces production of IL-10 and is associated with increased CD4+ CD25+ regulatory T cells.

Despite steady progress in elimination of measles virus globally, measles infection still causes 500,000 annual deaths, mostly in developing countries where endemic measles strains still circulate. Many adults are infected every year in China, with symptoms more severe than those observed in children. In this study, we have used blood samples from adult measles patients in Shanghai and age-matched healthy controls to gain an understanding of the immune status of adult measles patients. IFN-alpha mRNA was reduced in patient PBMC compared with healthy controls. In contrast, gene expression and plasma production of IL-2, IL-10, and IFN-gamma were elevated in patient blood. A similar cytokine profile was observed at early times when cultured PBMC were infected with a clinical isolate of measles virus. In contrast to previous studies in pediatric patients, we did not find a reduction in total CD4(+) and CD8(+) T cells in patient PBMC. Interestingly, we found that CD4(+)CD25(+)CD127(low) regulatory T cells were significantly increased in patient PBMC compared with controls. Using intracellular cytokine staining we also show that the measles virus induces IL-10-producing CD14(+) and CD4(+)CD25(+) cells in PBMC. Our results show that adult measles patients in the acute phase of the disease have a mixed Th1/Th2 type response, accompanied with severe immunosuppression of both innate and adaptive responses including suppression of type I IFN. Both regulatory T cells and plasma IL-10 may contribute to the immunosuppression.

Aspergillus fumigatus conidia upregulates NOD2 protein expression both in vitro and in vivo.

AIM: To determine if NOD2 is involved in host recognition of Aspergillus fumigatus (Af) conidia. METHODS: An Af conidia pulmonary infection murine model was established by intranasal inoculation of Af conidia suspensions. Protein levels of NOD2 in lung tissue were determined by immunohistochemistry. A549 and phorbol-12-myristate 13-acetate (PMA)-activated THP-1 cell lines were treated with heat-killed Af conidia, then the presence of NOD2 protein in these cell lines was detected by Western blotting. The ability of muramyl dipeptide (MDP) to induce the secretion of TNF-alpha after incubation with heatkilled Af conidia was measured by enzyme-linked immunosorbent assay. RESULTS: The expression of NOD2 protein in lung tissue increased after Af conidia infection. Heat-killed Af conidia significantly upregulated NOD2 protein expression in A549 cells and PMA-activated THP-1 cells. Additionally, Af conidia in conjuction with MDP, significantly increased the secretion of TNF-alpha in A549 cells and PMA-activated THP-1 cells. CONCLUSION: Af conidia upregulates NOD2 protein expression in vitro and in vivo. These findings indicate that NOD2 protein may respond to Af conidia.

A randomized controlled phase IIb trial of antigen-antibody immunogenic complex therapeutic vaccine in chronic hepatitis B patients.

BACKGROUND: The safety of the immune complexes composed of yeast-derived hepatitis B surface antigen (HBsAg) and antibodies (abbreviated as YIC) among healthy adults and chronic hepatitis B patients has been proved in phase I and phase IIa trial. A larger number of patients for study of dosage and efficacy are therefore needed. METHODS AND PRINCIPAL FINDINGS: Two hundred forty two HBeAg-positive chronic hepatitis B patients were immunized with six injections of either 30 microg YIC, 60 microg of YIC or alum adjuvant as placebo at four-week intervals under code. HBV markers and HBV DNA were monitored during immunization and 24 weeks after the completion of immunization. The primary endpoint was defined as loss of HBeAg, or presence of anti-HBe antibody or suppression of HBV DNA, while the secondary endpoint was both HBeAg seroconversion and suppression of HBV DNA. Statistical significance was not reached in primary endpoints four weeks after the end of treatment among three groups, however, at the end of follow-up, HBeAg sero-conversion rate was 21.8% (17/78) and 9% (7/78) in the 60 microg YIC and placebo groups respectively (p = 0.03), with 95% confidence intervals at 1.5% to 24.1%. Using generalized estimating equations (GEEs) model, a significant difference of group effects was found between 60 microg YIC and the placebo groups in terms of the primary endpoint. Eleven serious adverse events occurred, which were 5.1%, 3.6%, and 5.0% in the placebo, 30 microg YIC and 60 microg YIC groups respectively (p>0.05). CONCLUSIONS: Though statistical differences in the preset primary and secondary endpoints among the three groups were not reached, a late and promising HBeAg seroconversion effect was shown in the 60 microg YIC immunized regimen. By increasing the number of patients and injections, the therapeutic efficacy of YIC in chronic hepatitis B patients will be further evaluated. TRIAL REGISTRATION: ChiCTR.org ChiCTR-TRC-00000022.

[A study on the mechanisms of mycobacterial clearance induced by CpG-oligodeoxynucleotides in mice].

OBJECTIVE: To investigate the possible mechanisms of mycobacterial clearance induced by CpG-oligodeoxynucleotides (CpG-ODN) in mice. METHODS: Eight-week-old female BALB/c mice were treated with intraperitoneal CpG-ODN (30 microg), while the control mice with normal saline. After 2 weeks, the control mice and the CpG-treated mice were infected with Mycobacterium tuberculosis (1 x 10(6) colony-forming units, H(37)Rv strain) through the tail vein. At 3 weeks, 4 weeks and 6 weeks after mycobacterial infection, the lung and the spleen tissues were examined for histopathological changes. Real time-PCR was performed to measure the messenger RNA (mRNA) of interleukin (IL)-12, IL-18, interferon (IFN)-gamma, IL-4, IL-10 and inducible nitric oxide synthase (iNOS) in the tissues. The homogenates of lungs and spleens were cultured, and the colonies were counted after a 4 weeks incubation period at 37 degrees C. RESULTS: At 3 weeks and 4 weeks of mycobacterial infection, CpG-ODN-pretreated mice showed less mycobacterial burden in the lungs and the spleens than that in the control mice [(0 +/- 0) x 10(6) CFU/g vs (32 +/- 11) x 10(6) CFU/g, (0 +/- 0) x 10(6) CFU/g vs (10 +/- 4) x 10(6) CFU/g; (26 +/- 4) x 10(6) CFU/g vs (56 +/- 8) x 10(6) CFU/g, (4 +/- 3) x 10(6) CFU/g vs (27 +/- 8) x 10(6) CFU/g]. At 4 weeks of mycobacterial infection, CpG-ODN-pretreated mice displayed increased levels of IL-18 mRNA, IFN-gamma mRNA, iNOS mRNA [(3.6 +/- 0.5, 1.6 +/- 1.1, 0.32 +/- 0.14) vs (0.20 +/- 0.10, 23.17 +/- 4.72, 16.18 +/- 5.09)], and decreased level of IL-12p40 mRNA (5.66 +/- 0.64 vs 14.54 +/- 1.89), but there was no difference in the levels of IL-4 mRNA and IL-10 mRNA in the lungs between CpG-ODN-pretreated mice and the control mice [(0.30 +/- 0.09 vs 0.26 +/- 0.05), (0.28 +/- 0.05 vs 0.29 +/- 0.08)]. CpG-ODN-pretreated mice displayed increased levels of IL-18 mRNA, IFN-gamma mRNA, iNOS mRNA [(5.54 +/- 1.29 vs 0.79 +/- 0.36), (0.52 +/- 0.07 vs 0.21 +/- 0.06), (9.07 +/- 1.81 vs 5.97 +/- 1.44)], and decreased levels of IL-12p40 mRNA, IL-4 mRNA and IL-10 mRNA [(2.10 +/- 0.27 vs 5.07 +/- 0.39), (0.23 +/- 0.10 vs 1.21 +/- 0.26), (0.10 +/- 0.04 vs 0.57 +/- 0.13)] in the spleens as compared with the control mice. In CpG-ODN-pretreated mice, expression level of IFN-gamma mRNA in the lungs at 6 weeks post-infection was higher than that at 4 weeks post-infection (0.95 +/- 0.27 vs 0.32 +/- 0.14). CONCLUSION: The activation of Toll-like receptor-9 (TLR-9) with CpG-ODN could enhance murine mycobacterial clearance in vivo. TLR-9-induced anti-mycobacterial activity involves increased expression of IL-18, IFN-gamma, and iNOS but decreased expression of IL-4 and IL-10.

Localization of CD8+ cells specific for hepatitis B virus surface protein in the liver of immunized mice.

DNA plasmids are potent inducers of long-lasting antigen-specific CTL responses. Little is known about the distribution of antigen-specific CD8+ T cells in the lymphoid tissue and the non-lymphoid tissue after DNA immunization. HBsAg-specific CD8+ T cells in peripheral blood mononuclear cells, spleen, lymph nodes, and the liver of Balb/c mice have been quantified after injection with a DNA plasmid expressing the major S protein of hepatitis B virus (HBV). The kinetics of CD8+ T-cell responses in the circulation were measured after priming and boosting, showing that antigen-specific CD8+ T cells undergo first expansion and then decline to a sustainable level in the circulation, although the frequencies of HBsAg-specific CD8+ T cells in the circulation were lower than for the spleen. The greater frequencies of HBsAg-specific CD8+ T cells were found in the liver, whereas the largest numbers of antigen-specific CD8+ T cells were found in the spleen. By day 100 after priming, HBsAg-specific CD8+ T cells were still detected in the circulation, the spleen and the liver. After boosting with the same plasmid DNA immunogen, HBsAg-specific CD8+ T cells proliferated quickly and vigorously. By 150 days after boosting, HBsAg-specific memory CD8+ T cells were sustained at higher levels than those recorded after the first, primary injection, both in the spleen and the liver: anti-HBs antibody-secreting plasma cells persisted in the bone marrow and in the spleen, consistent with the detection of anti-HBs antibodies detected in the blood. These findings indicate that DNA immunization has considerable potential for inducing specific T cell responses in the liver and offers a strategy for the development of post-exposure immunotherapy against persistent hepatitis B infections.

Therapeutic effect of hepatitis B surface antigen-antibody complex is associated with cytolytic and non-cytolytic immune responses in hepatitis B patients.

To study the responses of chronic hepatitis B patients to yeast-derived HBsAg-HBIG complexes (YIC) and the mechanisms involved, twenty HBeAg-positive chronic hepatitis B patients were immunized with 60microg of YIC or alum as the control at 4-week intervals, for 24 weeks. Five of ten patients responded to 60microg YIC immunization showing > or =2 logs decrease of serum HBV DNA with loss or marked reduction of HBeAg and appearance of anti-HBe; two of these patients developed anti-HBs. Flares of alanine aminotransferase were observed in 4 of the 5 responders, and in 2 out of 10 control patients. HBsAg-stimulated peripheral blood mononuclear cells (PBMCs) secreted Th1/Th2 cytokines around 24 weeks after immunization. Dendritic cells incubated with YIC showed the highest levels of IL-12 secretion and up-regulation of functional markers. Thus, the therapeutic effect of YIC is associated with cytolytic and non-cytolytic responses in patients.

[The effects of CpG-oligodeoxynucleotides on airway remodeling in chronic asthmatic mice].

OBJECTIVE: To investigate if CpG-oligodeoxynucleotides (CpG-ODN) intervention has inhibitory effects on the development of airway remodeling in an ovalbumin (OVA)-sensitized mouse model of chronic asthma. METHODS: Forty female C57BL/6 mice were randomly divided into four groups (n = 10): (1) Group A (chronic asthma model): mice were sensitized by intraperitoneal injection of OVA (10 microg) precipitated with aluminium hydroxide (100 microg) on days 1 and 14. From day 21, the mice were challenged by nebulized 2.5% OVA solution (30 min/d, three times a week for 8 weeks). (2) Group B (CpG-ODN intervention group): mice were sensitized and challenged as above, and were given 60 microg CpG-ODN by intraperitoneal injection for once every two weeks. (3) Group C (GpG-ODN control): Mice were given GpC-ODN instead of CpG motifs, other treatments same as Group B. (4) Group D (saline control): mice were sensitized and challenged by saline. All mice were killed 24 h after the final OVA challenge. Blood was obtained for eosinophil counts and measurement of serum IgE by enzyme-linked immunoabsorbent assay (ELISA). Bronchoalveolar lavage fluid (BALF) was collected for total and differential counts. The concentration of interleukin-13 (IL-13) and transforming growth factor-beta1 (TGF-beta(1)) in BALF was measured by ELISA. The left lung was isolated for pathological examination. Lung sections were stained with hematoxylin and eosin (HE), and Masson's trichrome. Other sections were prepared for immunohistochemistry using monoclonal antibodies against alpha-smooth muscle actin (alpha-SMA) and TGF-beta(1). RESULTS: The eosinophil count [(89 +/- 10) x 10(4)/ml], serum IgE [(279 +/- 53) ng/ml], BALF eosinophils [(6.30 +/- 1.30) x 10(5)/ml] and the concentrations of BALF IL-13 [(4 015 +/- 361) pg/ml] and TGF-beta(1) [(356 +/- 64) pg/ml] in the OVA-sensitized mice (Group A) showed significant difference as compared with those in the NS control group (Group D, t values are 24.0, 15.7, 14.7, 18.4, 12.0 and 18.9 respectively, all P < 0.01). In Group A, the percentages of positive staining area in Masson's trichrome, alpha-SMA staining and TGF-beta(1) staining were (29.7 +/- 4.2)%, (45 +/- 7)% and (34 +/- 4)% respectively. These percentages were significantly different from those in the NS control group (Group D, t values are 18.0, 15.6 and 17.9 respectively, all P < 0.01). In mice treated with CpG-ODN (Group B), the percentages of positive staining area in Masson's trichrome, alpha-SMA staining and TGF-beta(1) staining were (13.8 +/- 3.2)%, (24.7 +/- 3.1)%, (18 +/- 4)% respectively, which were significantly different from those in Group A (t values are 9.5, 8.9 and 9.8 respectively, all P < 0.05). CONCLUSIONS: This study demonstrated that CpG-ODN could prevent Th2 responses, eosinophilic inflammation and the development of airway remodeling. Its inhibitory effect on airway remodeling might, in part, be due to inhibition of the expression of cytokines such as TGF-beta(1) and IL-13.