Recovery of natural killer cells is mainly in post-treatment period in chronic hepatitis C patients treated with sofosbuvir plus ledipasvir

AIM

To investigate how natural killer (NK) cells are affected in the elimination of hepatitis C virus (HCV) by sofosbuvir/ledipasvir, two highly effective direct-acting antivirals (DAAs).

METHODS

Thirteen treatment-naïve and treatment-experienced chronic hepatitis C (CHC) patients were treated with sofosbuvir/ledipasvir, and NK cells were detected at baseline, weeks 2, 4, 8 and 12 during therapy, and week post of treatment (Pt)-12 and 24 after the end of therapy by multicolor flow cytometry and compared with those from 13 healthy controls.

RESULTS

All patients achieved sustained virological response. There was a significant decline in CD56bright NK cell frequencies at week 8 (P = 0.002) and week 12 (P = 0.003), which were altered to the level comparable to healthy controls at week Pt-12, but no difference was observed in the frequency of CD56dim NK cells. Compared with healthy controls, the expression levels of NKG2A, NKp30 and CD94 on NK cells from CHC patients at baseline were higher. NKG2A, NKp30 and CD94 started to recover at week 12 and reached the levels similar to those of healthy controls at week Pt-12 or Pt-24. Before treatment, patients have higher interferon (IFN)-γ and perforin levels than healthy controls, and IFN-γ started to recover at week 8 and reached the normalized level at week Pt-12.

CONCLUSION

NK cells of CHC patients can be affected by DAAs, and phenotypes and function of NK cells recover not at early stage but mainly after the end of sofosbuvir/ledipasvir treatment.

Edible Gum-Phenolic-Lipid Incorporated Gluten Films for Food Packaging

The aim of this investigation was to improve the barrier and mechanical properties of gluten films and further explore their application in the packaging of seasonings. The effects of flaxseed gum (FG), oligomeric procyanidins (OPCs), and lauric acid (LA) on the water vapor permeability (WVP), mechanical properties, and peroxide value (POV) were determined. FG and OPCs improved the WVP properties of the gluten films, whereas LA significantly improved the oxygen-barrier properties. The FG/OPCs/LA/GP composite film was then optimized, and the morphological, microstructural, and thermal properties of the composite gluten film were investigated by scanning electron microscopy, atomic force microscopy, surface hydrophobicity analysis; Fourier transform infrared spectroscopy; thermal gravimetric analysis, respectively. The results confirmed that gluten is compatible with FG, OPCs, and LA, thereby leading to the formation of a more uniform, dense, and hydrophobic film. The changes in the preservation properties (appearance, POV, and acid value) of the composite gluten film for oil, salt, and vegetable packaging were also examined. The composite gluten film maintained some degree of seasoning packaging capacity over a 75-day storage period, indicating its potential for uses as a packaging material for seasonings in food production.

PRACTICAL APPLICATION

The edible composite film will be produced in industry according to the data provided in our paper; the film can be used as packaging material for seasonings in food production.

Rapid specific and visible detection of porcine circovirus type 3 using loop-mediated isothermal amplification (LAMP)

In this study, a rapid and specific assay for the detection of porcine circovirus type 3 (PCV3) was established using loop-mediated isothermal amplification (LAMP). Four primers were specifically designed to amplify PCV3. The LAMP assay was effectively optimized to amplify PCV3 by water bath at 60°C for 60 min. The detection limit was approximately 1 × 10¹ copy in this LAMP assay. Compared to porcine circovirus type 2 (PCV2), both gE and gD genes of pseudorabies virus (PRV) and porcine parvovirus (PPV), the LAMP assay showed a high specific detection of PCV3. A visible detection method was developed using SYBR Green I to recognize the results rapidly. Based on the detection of 20 clinical tissue samples, the LAMP assay was more practical and convenient than classical PCR due to its simplicity, high sensitivity, rapidity, specificity, visibility and cost efficiency.

[A 20-year study on microvascular autologous transplantation of submandibular gland for treatment of severe dry eye]

Severe dry eye is a refractory ophthalmologic disease. Our multidisciplinary research group treated severe dry eye by microvascular autologous transplantation of submandibular gland (SMG) during the past 20 years. The SMG, with its blood vessels and Wharton's duct, was harvested from the submandibular triangle and transferred to the temporal area. The blood vessels in the SMG were anastomosed with the temporal blood vessels using a microsurgical technique. Then, the distal end of Wharton's duct was sutured to form an opening in the upper lateral conjunctival fold. The tear was replaced by the secretion of the transplanted SMG to lubricate the ocular surface. In our study, the surgical techniques of blood vessel management were continuously modified to increase the survival rate of the transplanted SMG. A novel surgical modality of partial transplantation of SMG was established to prevent postoperative epiphora. A clinical study with the largest case number in the world was conducted and the effectiveness of transplantation of SMG for severe dry eye was fully confirmed. In order to resolve two main clinical problems including ductal obstruction resulted from low secretion rate during the latent period, and epiphora due to over secretion of the transplanted SMG in the later term of transplantation, the regulation of the secretion mechanism of the normal and transplanted SMG were investigated. New opinions on mechanisms of saliva secretion were provided. Based on the priniciple of translational medicine, the results of related basic research were applied in the clinic. The clinical guidelines for secretion regulation of transplanted SMG were established. A concept of chronic obstructive sialadenitis of transplanted SMG was provided and its diagnostic criteria, diagnostic technique of sialography, and therapeutic regimen were established. As a result, the surgical success rate was obviously elevated, the surgical complications were decreased, and life quality of the patients was greatly improved.

MYL6B, a myosin light chain, promotes MDM2-mediated p53 degradation and drives HCC development

BACKGROUND

Identification of novel MDM2 or p53 binding proteins may reveal undefined oncogenes, tumor suppressors, signaling pathways and possible treatment targets.

METHODS

By means of immunoprecipitation and Mass Spectrometry analysis, we aimed to identify novel regulators of the MDM2-p53 pathway. We further clarified the impact of MYL6B on the p53 protein level and on the process of apoptosis. We also investigated the role of MYL6B in hepatocellular carcinoma by clone formation assay and by determining the correlation between its expression and prognosis of HCC patients.

RESULTS

We identified a novel MDM2 and p53 binding protein, MYL6B. It is a myosin light chain that could bind myosin II heavy chains to form non-muscle myosin II holoenzymes (NMII). We found that MYL6B could facilitate the binding of MDM2 to p53, which consequently promotes the ubiquitination and degradation of p53 protein. We further proved that MYL6B exerts the suppression effect on p53 as part of NMII holoenzymes because inhibiting the ATPase activity of myosin II heavy chain largely blocked this effect. We also discovered that MYL6B is overexpressed in HCC tissues and linked to the bad prognosis of HCC patients. Knocking out of MYL6B dramatically suppressed the clonogenic ability and increased the apoptosis level of HCC cell lines.

CONCLUSIONS

To summary, our results demonstrate that MYL6B is a putative tumor driver gene in HCC which could promote the degradation of p53 by enhancing its' MDM2-mediated ubiquitination.

Presence of Torque teno sus virus 1 and 2 in porcine circovirus 3-positive pigs

In this study, the co-infection of Torque teno sus virus (TTSuV) and porcine circovirus type 3 (PCV3) was reported. One hundred and ten of 132 (83.3%) PCV3-positive samples were co-infected with Torque teno sus virus 1 (TTSuV1). Ninety-four of 132 (71.2%) PCV3-positive samples were co-infected with Torque teno sus virus 2 (TTSuV2). Sixty-six of 132 (50.0%) of PCV3-positive samples were co-infected with both TTSuV1 and TTSuV2. There were no clinical signs of infection in pigs that were both PCV3-positive and PCV2-negative, in either multiparous sows or live-born infants. The high co-infection rate provides valuable information for the further study of the pathological correlation between PCV3 and TTSuVs.

Abnormal phenotypic features of IgM+B cell subsets in patients with chronic hepatitis C virus infection

Hepatitis C virus (HCV) infection is associated with B cell abnormality; however the phenotypic profiles of immunoglobulin (Ig)M+B cell subsets in patients with HCV infection remain unclear. In the current study, the effect of HCV infection on IgM+B cell subsets was evaluated. The percentages, as well as the differentiation and activation features of peripheral IgM+B naive subsets [cluster of differentiation (CD)27-IgM+B cells] and IgM+B memory subsets (CD27+IgM+B cells) were assessed using flow cytometry in 27 patients with chronic hepatitis C (CHC) and 20 healthy controls (HCs). The frequency of CD27+IgM+B memory subsets detected in patients with CHC was significantly higher than that in HCs (P<0.05). Although the frequency of CD27-IgM+B naive subsets was similar in both groups, there was a significantly higher proportion of CD5+B cells detected in the CD27-IgM+B subsets of patients with CHC compared with HCs (P<0.05). Among CD27-IgM+B subsets, abnormal differentiation was associated with HCV infection, with significantly increased percentages of IgD+B cells and CD38+B cells in patients with CHC compared with HCs (P<0.05). In CD27+IgM+B memory subsets, the abnormality of cell differentiation was associated with a significantly increased percentage of CD38+B cells in patients with CHC compared with HCs (P<0.05). In addition, the percentage of activated CD27+IgM+B subsets in patients with CHC were significantly higher than those observed in HCs (P<0.05). The number of CD27-IgD+IgM+B, CD27-CD38+IgM+B and CD27+CD38+IgM+B cells were negatively correlated with HCV RNA in patients with CHC. These results suggest that HCV infection contributes to abnormalities in the percentage, differentiation and activation of IgM+B cell subsets and may disrupt the immune response mediated by IgM+B cells.

PPPDE1 is a novel deubiquitinase belonging to a cysteine isopeptidase family

Ubiquitinlation of proteins is prevalent and important in both normal and pathological cellular processes. Deubiquitinating enzymes (DUBs) can remove the ubiquitin tags on substrate proteins and dynamically regulate the ubiquitination process. The PPPDE family proteins were predicted to be a novel class of deubiquitinating peptidase, but this has not yet been experimentally proved. Here we validated the deubiquitinating activity of PPPDE1 and revealed its isopeptidase activity against ubiquitin conjugated through Lys 48 and Lys 63. We also identified ribosomal protein S7, RPS7, as a substrate protein of PPPDE1. Moreover, PPPDE1 could mediate the ubiquitin chain editing of RPS7, deubiquitinating Lys 48-linked ubiquitination, and finally stabilize RPS7 proteins. Taken together, we report that PPPDE1 is a novel deubiquitinase that belongs to a cysteine isopeptidase family.

Endothelial Tight Junctions Are Opened in Cholinergic-Evoked Salivation In Vivo

Blood vessels provide the original supplies for the formation of primary saliva, which is regulated by the tight junctions (TJs) between endothelial cells. Previous studies have shown that blood flow increases with vasodilatation during cholinergic-evoked salivation. However, changes in vascular paracellular permeability and the role of endothelial TJs in salivation are unknown. Here, we established an in vivo paracellular permeability detection system and observed that the endothelial TJs were permeable to 4-kDa fluorescein isothiocyanate (FITC)-dextran while impermeable to 40- and 70-kDa FITC-dextran under an unstimulated condition in mouse submandibular glands (SMGs). Pilocarpine increased the flux of 4- and 40-kDa FITC-dextran out of blood vessels but did not affect 70-kDa FITC-dextran. Claudin 5, a TJ protein specifically localized in salivary endothelial cells, was redistributed from the apicolateral membranes to the lateral and basolateral membranes and cytoplasm in cholinergic-stimulated mouse SMGs and freshly cultured human SMG tissues. In the transplanted SMGs from epiphora patients, we found that claudin 5 was present in the basolateral membranes and cytoplasm, instead of the apical region in control SMGs. Moreover, the level of phospho-myosin light chain 2 increased within the blood vessels of the pilocarpine-stimulated mouse SMGs and transplanted human SMGs, while the downstream molecule F-actin was reorganized in the endothelial cells of the transplanted human SMGs. Taken together, our findings provide direct visual evidence that the opening of endothelial TJs and the redistribution of claudin 5 are essential events contributing to cholinergic-evoked salivation, thus enriching our understanding of the secretory mechanisms that link blood flow to primary saliva formation by regulating the endothelial paracellular permeability.

Role of intrahepatic B cells in non-alcoholic fatty liver disease by secreting pro-inflammatory cytokines and regulating intrahepatic T cells

OBJECTIVE

To investigate the alterations and functions of intrahepatic B (IHB) cells in non-alcoholic fatty liver disease (NAFLD) model induced by high-fat diet (HFD).

METHODS

C57BL/6 J mice were fed with HFD for 16 weeks to induce NAFLD. Flow cytometry was used to analyze lymphocytes from liver, spleen and peripheral blood mononuclear cells (PBMC). Real-time polymerase chain reaction and immunofluorescence stain were applied to investigate cytokine expression in the intrahepatic lymphocytes and IHB cells. CD4(+) intrahepatic T (IHT) cells and IHB cells were enriched by a magnetic-activated cell sorting method and cultured in vitro. The cytokines and immunoglobulin (Ig) levels in the plasma, cultural supernatants and liver homogenates were monitored with cytometric bead arrays or multiplex immunoassays.

RESULTS

The percentage of IHB cells in CD45(+) cells was significantly higher in the NAFLD group than in the control group (P < 0.05). IHB cells expressed higher levels of interleukin (IL)-6 and tumor necrosis factor (TNF)-α in the NAFLD group, and produced higher levels of IL-6 and TNF-α under the stimulation of lipopolysaccharide (LPS) than the control group. IgG2a levels were higher in the plasma, liver homogenates and the culture supernatants of IHB cells after stimulated by LPS and anti-CD40/IgM in the NAFLD group than in the control group. Moreover, IHB cells enhanced the activation of CD4(+) IHT cells and promoted the differentiation into T helper (Th) 1 cells in the NAFLD group.

CONCLUSION

IHB cells might be involved in NAFLD both by inducing the secretion of IL-6, TNF-α and IgG2a and by enhancing the activation of CD4(+) IHT cells and their differentiation into Th1 cells.

Interleukin-17 Impairs Salivary Tight Junction Integrity in Sjögren's Syndrome

Sjögren's syndrome (SS) is an inflammatory autoimmune disease that causes secretory dysfunction of the salivary glands. It has been reported that proinflammatory cytokine interleukin-17 (IL-17) was elevated and tight junction (TJ) integrity disrupted in minor salivary glands from SS patients. However, whether the elevated IL-17 in SS affects TJ integrity and thereby alters the function of salivary gland is unknown. Here, by using nonobese diabetic (NOD) mice as SS model, we found that the stimulated salivary flow rate was significantly decreased in NOD mice. Lymphocyte infiltration was mainly observed in submandibular glands (SMGs), but not parotid glands (PGs), of NOD mice. IL-17 was significantly increased and mainly located in lymphocytic-infiltrating regions in SMGs but not detectable in PGs of NOD mice. Meanwhile, the epithelial barrier function was disrupted, as evidenced by an increased paracellular tracer clearance and an enlarged acinar TJ width in SMGs of NOD mice. Furthermore, claudin-1 and -3 were elevated especially at the basolateral membranes, whereas claudin-4, occludin, and zonula occludens-1 (ZO-1) were reduced in SMGs of NOD mice. Moreover, occludin and ZO-1 were dispersed into cytoplasm in SMGs of NOD mice. However, no change in the expression and distribution of TJ proteins was found in PGs. In vitro, IL-17 significantly decreased the levels and apical staining of claudin-4 and ZO-1 proteins in the cultured SMG tissues, as well as claudin-1, occludin, and ZO-1 in PG tissues. Moreover, IL-17 activated the phosphorylation of IκBα and p65 in SMG cells, whereas pretreatment with NF-κB inhibitor pyrrolidine dithiocarbamate suppressed the IL-17-induced downregulation of claudin-4 and ZO-1 in SMG tissues. Taken together, these findings indicate that IL-17 derived from infiltrating lymphocyte impairs the integrity of TJ barrier through NF-κB signaling pathway, and thus might contribute to salivary gland dysfunction in SS.

Gut-derived lymphocyte recruitment to liver and induce liver injury in non-alcoholic fatty liver disease mouse model

BACKGROUND AND AIM

Most studies focus on gut-derived factors like microbiota and its products and how they contribute to non-alcoholic fatty liver disease (NAFLD) progression. This study investigated whether the gut-derived lymphocytes could migrate to the liver and induce liver injury in NAFLD.

METHODS

A high-fat diet induced an NAFLD mouse model, and lymphocytes were labeled with 1,1-dioctadecyl-3,3,3,3 tetramethylindotricarbocyanine iodide and carboxy-fluorescein succinimidyl ester, respectively, and intravenously injected to mice to monitor lymphocyte migration.

RESULTS

Adoptive transfer model results indicated that compared with lymphocytes from the spleen, bone marrow and thymus of NAFLD donor mice, mesenteric lymph nodes (MLN) cells from NAFLD donor mice predominately accumulated in the livers of NAFLD recipient mice. The frequencies of central memory CD4(+) T and CD8(+) T cells in livers of NAFLD mice were significantly increased; however, the activated T cells were not significantly altered. After adoptively transferred MLN cells, the frequencies of the activated CD4(+) T and CD8(+) T cells increased in livers of NAFLD recipient mice. By contrast, the frequencies of central memory and naïve CD4(+) T and CD8(+) T cells decreased. MLN cells also induced liver injury in NAFLD recipient mice, as reflected by elevated serum alanine aminotransferase and glutamic oxaloacetic transaminase serums. Moreover, the chemotaxis assay showed that CCL5 mediated the MLN cell migration to the liver. Also, blocking the CCL5 inhibited MLN cell migration to the liver in vitro.

CONCLUSIONS

Gut-derived lymphocytes from NAFLD mice could migrate to the liver and induce liver injury and hepatic CD4(+) T and CD8(+) T cells activation. The migration was associated with the upregulation of CCL5 in the liver.

CD4+CXCR5+ T cells activate CD27+IgG+ B cells via IL-21 in patients with hepatitis C virus infection

BACKGROUND

Chronic hepatitis C virus (HCV) infection causes the skewing and activation of B cell subsets, but the characteristics of IgG+ B cells in patients with chronic hepatitis C (CHC) infection have not been thoroughly elucidated. CD4+CXCR5+ follicular helper T (Tfh) cells, via interleukin (IL)-21 secretion, activate B cells. However, the role of CD4+CXCR5+ T cells in the activation of IgG+ B cells in CHC patients is not clear.

METHODS

The frequency of IgG+ B cells, including CD27-IgG+ B and CD27+IgG+ B cells, the expression of the activation markers (CD86 and CD95) in IgG+ B cells, and the percentage of circulating CD4+CXCR5+ T cells were detected by flow cytometry in CHC patients (n=70) and healthy controls (n=25). The concentrations of serum IL-21 were analyzed using ELISA. The role of CD4+CXCR5+ T cells in the activation of IgG+ B cells was investigated using a co-culture system.

RESULTS

A significantly lower proportion of CD27+IgG+ B cells with increased expression of CD86 and CD95 was observed in CHC patients. The expression of CD95 was negatively correlated with the percentage of CD27+IgG+ B cells, and it contributed to CD27+IgG+ B cell apoptosis. Circulating CD4+CXCR5+ T cells and serum IL-21 were significantly increased in CHC patients. Moreover, circulating CD4+CXCR5+ T cells from CHC patients induced higher expressions of CD86 and CD95 in CD27+IgG+ B cells in a co-culture system; the blockade of the IL-21 decreased the expression levels of CD86 and CD95 in CD27+IgG+ B cells.

CONCLUSIONS

HCV infection increased the frequency of CD4+CXCR5+ T cells and decreased the frequency of CD27+IgG+ B cells. CD4+CXCR5+ T cells activated CD27+IgG+ B cells via the secretion of IL-21.

ZO-1 and -2 Are Required for TRPV1-Modulated Paracellular Permeability

The tight junction–based paracellular pathway plays an important role in saliva secretion. Zonula occludens (ZO) proteins are submembranous proteins of tight junction complex; however, their function in salivary epithelium is poorly understood. Here, we found that activation of transient receptor potential vanilloid subtype 1 (TRPV1) by capsaicin increased rat saliva secretion both in vivo and ex vivo. Meanwhile, TRPV1 activation enlarged the width of tight junctions between neighboring acinar cells, increased the paracellular flux of 4-kDa fluorescein isothiocyanate (FITC)-dextran in submandibular gland (SMG) tissues, and decreased transepithelial electric resistance (TER) in SMG-C6 cells. ZO-1, -2, and -3 were distributed principally to the apical lateral region of acinar cells in SMG tissues and continuously encircled the peripheries of SMG-C6 cells in the untreated condition. TRPV1 activation obviously diminished ZO-1 and -2 staining, but not ZO-3 or β-catenin, at the cell-cell contacts ex vivo and in vitro. Moreover, in untreated SMG-C6 cells, ZO-1 and -2 single or double knockdown by small interfering RNA (siRNA) increased the paracellular flux of 4-kDa FITC-dextran. In capsaicin-treated cells, ZO-1 and -2 single or double knockdown abolished, whereas their re-expression restored, the capsaicin-induced increase in paracellular permeability. Furthermore, TRPV1 activation increased RhoA activity, and inhibition of either RhoA or Rho kinase (ROCK) abolished the capsaicin-induced TER decrease as well as ZO-1 and -2 redistribution. These results indicate that ZO-1 and -2 play crucial roles in both basal salivary epithelial barrier function and TRPV1-modulated paracellular transport. RhoA-ROCK signaling pathway is responsible for TRPV1-modulated paracellular permeability as well as ZO-1 and -2 redistribution.

GII.4 Sydney_2012 norovirus infection in immunocompromised patients in Beijing and its rapid evolution in vivo

To study the epidemiology and evolution of norovirus (NoV) in immunocompromised patients in a tertiary hospital in China. Stool specimens were collected from 131 hospitalized patients presenting with diarrhea from July 1, 2012, to June 30, 2013, and were tested for NoV using RT-PCR. RT-PCR was performed to amplify the complete capsid genome for a series of samples from chronic diarrhea patients, and nucleotide and amino acid changes were analyzed. There were nine NoV-positive patients among 124 immunocompromised patients (7.3%); all nine were infected with GII.4 Sydney_2012 strain. In three chronic diarrhea patients, the GII.4 Sydney_2012 strains accumulated 19, 18, and eight nucleotide mutations within 110, 113, and 22 days, respectively, most were non-synonymous. The greatest number of stable amino acid mutations was 10 in patient 2; eight stable mutations (including three in antigenic sites) occurred while the patient was asymptomatic and shedding the virus. GII.4 Sydney_2012 strain tends to undergo stable mutations during the asymptomatic shedding phase and may generate new variants in chronic diarrhea patients.

Abnormal CD4 + T helper (Th) 1 cells and activated memory B cells are associated with type III asymptomatic mixed cryoglobulinemia in HCV infection

Background

Mixed cryoglobulinemia (MC) in hepatitis C virus (HCV) infection is associated with abnormal immune responses mediated by T cells and B cells, while the relationships of different subsets of CD4 + T helper (Th) cells, B cells and associated cytokines with type III asymptomatic MC in HCV infection are poorly understood.

Methods

Fifty-four chronic hepatitis C (CHC) patients and 23 healthy controls (HCs) were enrolled in the study. Serum cryoglobulins were detected by cryoprecipitation. The types of cryoglobulin were determined by western blot. The phenotypes and frequencies of Th cell and B cell subsets were detected by flow cytometric analysis. The cytokines IFN-γ, IL-4, IL-17, IL-21, IL-22, and TGF-β were measured by enzyme-linked immunosorbent assay.

Results

Twenty-six CHC patients were detected with type III asymptomatic MC. The frequencies of Th2, Th17, follicular helper T (Tfh cells), Th22, and tissue-like B cells were significantly higher in CHC patients compared to HCs, while these cell subsets were not significantly different between CHC patients and HCV-related MC patients. The frequencies of Th1 and activated memory B cells increased in HCV-related MC patients compared to HCs, although the difference between the two cell subsets in CHC patients and HCs was not significant. The frequency of regulatory T cells (Treg cells) was higher in CHC patients than in HCV-related MC patients and HCs. Higher expressions of serum IFN-γ, IL-17, IL-21, and IL-22 were observed in CHC patients than in HCs, but the differences were not significantly different in CHC patients and HCV-related MC patients. The frequency of Th1 cells was associated with activated memory B cells in HCV-related MC patients, and the frequency of Th1 cells and activated memory B cells was closely related to HCV RNA in HCV-related MC patients.

Conclusions

The increased frequencies of Th17 cells, Tfh cells, Th22 cells, Treg cells, cytokines IL-17, IL-21, IL-22, and tissue-like B cells, were related to HCV infection but not type III asymptomatic MC. Higher frequencies of Th1 cells and activated memory B cells were associated with type III asymptomatic MC in HCV infection.

Early predictive efficacy of core antigen on antiviral outcomes in genotype 1 hepatitis C virus infected patients

Response-guided therapy is of limited use in developing countries because hepatitis C virus RNA detection by sensitive molecular methods is time- and labor-consuming and expensive. We evaluated early predictive efficacy of serum hepatitis C virus core antigen kinetics on sustained virologic response in patients with genotype 1 hepatitis C virus during pegylated interferon plus ribavirin treatment. For 478 patients recruited, hepatitis C virus RNAs were detected at baseline, and at weeks 4, 12, 24, 48, and 72 using Cobas TaqMan. Architect hepatitis C virus core antigen was performed at baseline, and weeks 4 and 12. Predictive values of hepatitis C virus core antigen on sustained virologic response were compared to hepatitis C virus RNA. In the first 12 weeks after treatment initiation the dynamic patterns of serum hepatitis C virus core antigen and hepatitis C virus RNA levels were similar in sustained virologic response, relapse, and null response patients groups. Although areas under the receiver operating characteristics curves of hepatitis C virus core antigen were lower than those of hepatitis C virus RNA at the same time points, modeling analysis showed that undetectable hepatitis C virus core antigen (rapid virological response based on hepatitis C virus core antigen) had similar positive predictive value on sustained virologic response to hepatitis C virus RNA at week 4 (90.4% vs 93.3%), and hepatitis C virus core antigen decrease greater than 1 log₁₀ IU/mL (early virological response based on hepatitis C virus core antigen) had similar negative predictive value to hepatitis C virus RNA at week 12 (94.1% vs 95.2%). Analysis on the validation group demonstrated a positive predictivevalue of 97.5% in rapid virological response based on hepatitis C virus core antigen and a negative predictive value of 100% in early virological response based on hepatitis C virus core antigen. In conclusion, hepatitis C virus core antigen is comparable to hepatitis C virus RNA in predicting sustained virologic response of chronic genotype 1 hepatitis C virus infected patients, and can be used to guide anti-hepatitis C virus treatment, especially in resource-limited areas.

Pre- and Post-synaptic Effects of Botulinum Toxin A on Submandibular Glands

Intraglandular injection of botulinum toxin type A (BoNT/A) is an effective treatment for sialorrhea. Despite numerous experimental and clinical studies on inhibition of saliva section by BoNT/A, the proteolysis of synaptosomal-associated protein 25 (SNAP-25) following BoNT/A treatment has not yet been confirmed in the salivary gland after injection of BoNT/A. More important, it is not known whether BoNT/A exerts a direct effect in acinar cells. Here, we show that injection of BoNT/A into the rat submandibular gland (SMG) decreased salivary flow in a dose-dependent manner; the inhibitory effect lasted at least 4 wk, and salivary flow recovered to normal levels by 12 wk. During the inhibitory period, SMG neurons and synapses expressed lower levels of full-length SNAP-25, and cleavage of SNAP-25 was observed, as indicated by detection of reduced molecular weight SNAP-25 using Western blotting. In addition, the water channel aquaporin 5 (AQP5) was downregulated and abnormally distributed in rat SMG after injection of BoNT/A. The direct effects of BoNT/A on AQP5 expression and distribution were assessed in vitro to exclude the influence of BoNT/A-induced inhibitory neurotransmission. In stable GFP-AQP5-transfected SMG-C6 cells, treatment with BoNT/A reduced the cell surface protein level of AQP5 in a dose- and time-dependent manner without affecting total AQP5 protein expression. Cell surface biotinylation and immunofluorescence demonstrated translocation of AQP5 from the membrane to the cytoplasm, which was confirmed by decreased levels of AQP5 protein in the membrane fraction and increased levels in the cytoplasmic fraction, suggestive of AQP5 redistribution. Taken together, these results indicated that BoNT/A reversibly decreased saliva secretion in rat SMGs through not only the presynaptic SNAP-25 cleavage but also the postsynaptic AQP5 redistribution. These data provide the first evidence for a direct effect of BoNT/A on the salivary gland.