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1.
Cell ; 185(7): 1223-1239.e20, 2022 03 31.
Article in English | MEDLINE | ID: mdl-35290801

ABSTRACT

While CRISPR screens are helping uncover genes regulating many cell-intrinsic processes, existing approaches are suboptimal for identifying extracellular gene functions, particularly in the tissue context. Here, we developed an approach for spatial functional genomics called Perturb-map. We applied Perturb-map to knock out dozens of genes in parallel in a mouse model of lung cancer and simultaneously assessed how each knockout influenced tumor growth, histopathology, and immune composition. Moreover, we paired Perturb-map and spatial transcriptomics for unbiased analysis of CRISPR-edited tumors. We found that in Tgfbr2 knockout tumors, the tumor microenvironment (TME) was converted to a fibro-mucinous state, and T cells excluded, concomitant with upregulated TGFß and TGFß-mediated fibroblast activation, indicating that TGFß-receptor loss on cancer cells increased TGFß bioavailability and its immunosuppressive effects on the TME. These studies establish Perturb-map for functional genomics within the tissue at single-cell resolution with spatial architecture preserved and provide insight into how TGFß responsiveness of cancer cells can affect the TME.


Subject(s)
Neoplasms , Tumor Microenvironment , Animals , Clustered Regularly Interspaced Short Palindromic Repeats/genetics , Genomics , Mice , Neoplasms/genetics , Transforming Growth Factor beta/genetics
2.
Cell ; 175(4): 1141-1155.e16, 2018 11 01.
Article in English | MEDLINE | ID: mdl-30343902

ABSTRACT

CRISPR pools are being widely employed to identify gene functions. However, current technology, which utilizes DNA as barcodes, permits limited phenotyping and bulk-cell resolution. To enable novel screening capabilities, we developed a barcoding system operating at the protein level. We synthesized modules encoding triplet combinations of linear epitopes to generate >100 unique protein barcodes (Pro-Codes). Pro-Code-expressing vectors were introduced into cells and analyzed by CyTOF mass cytometry. Using just 14 antibodies, we detected 364 Pro-Code populations; establishing the largest set of protein-based reporters. By pairing each Pro-Code with a different CRISPR, we simultaneously analyzed multiple phenotypic markers, including phospho-signaling, on dozens of knockouts. Pro-Code/CRISPR screens found two interferon-stimulated genes, the immunoproteasome component Psmb8 and a chaperone Rtp4, are important for antigen-dependent immune editing of cancer cells and identified Socs1 as a negative regulator of Pd-l1. The Pro-Code technology enables simultaneous high-dimensional protein-level phenotyping of 100s of genes with single-cell resolution.


Subject(s)
CRISPR-Cas Systems , Flow Cytometry/methods , Genomics/methods , Mass Spectrometry/methods , Single-Cell Analysis/methods , Animals , Epitopes/chemistry , Epitopes/classification , Epitopes/genetics , HEK293 Cells , Humans , Immunophenotyping/methods , Jurkat Cells , Mice, Inbred BALB C , Proteome/chemistry , Proteome/classification , Proteome/genetics , THP-1 Cells
3.
Immunity ; 48(2): 271-285.e5, 2018 02 20.
Article in English | MEDLINE | ID: mdl-29466757

ABSTRACT

Stem cells are critical for the maintenance of many tissues, but whether their integrity is maintained in the face of immunity is unclear. Here we found that cycling epithelial stem cells, including Lgr5+ intestinal stem cells, as well as ovary and mammary stem cells, were eliminated by activated T cells, but quiescent stem cells in the hair follicle and muscle were resistant to T cell killing. Immune evasion was an intrinsic property of the quiescent stem cells resulting from systemic downregulation of the antigen presentation machinery, including MHC class I and TAP proteins, and is mediated by the transactivator NLRC5. This process was reversed upon stem cell entry into the cell cycle. These studies identify a link between stem cell quiescence, antigen presentation, and immune evasion. As cancer-initiating cells can derive from stem cells, these findings may help explain how the earliest cancer cells evade immune surveillance.


Subject(s)
Hair Follicle/cytology , Immune Evasion , Immunologic Surveillance , Stem Cells/immunology , Animals , Antigen Presentation , Intracellular Signaling Peptides and Proteins/physiology , Killer Cells, Natural/immunology , Mice , Mice, Inbred C57BL , Muscles/cytology , Receptors, G-Protein-Coupled/physiology , Tumor Escape
4.
EMBO J ; 38(10)2019 05 15.
Article in English | MEDLINE | ID: mdl-30979777

ABSTRACT

The multifunctional influenza virus protein PB1-F2 plays several roles in deregulation of host innate immune responses and is a known immunopathology enhancer of the 1918 influenza pandemic. Here, we show that the 1918 PB1-F2 protein not only interferes with the mitochondria-dependent pathway of type I interferon (IFN) signaling, but also acquired a novel IFN antagonist function by targeting the DEAD-box helicase DDX3, a key downstream mediator in antiviral interferon signaling, toward proteasome-dependent degradation. Interactome analysis revealed that 1918 PB1-F2, but not PR8 PB1-F2, binds to DDX3 and causes its co-degradation. Consistent with intrinsic protein instability as basis for this gain-of-function, internal structural disorder is associated with the unique cytotoxic sequences of the 1918 PB1-F2 protein. Infusing mice with recombinant DDX3 protein completely rescued them from lethal infection with the 1918 PB1-F2-producing virus. Alongside NS1 protein, 1918 PB1-F2 therefore constitutes a potent IFN antagonist causative for the severe pathogenicity of the 1918 influenza strain. Our identification of molecular determinants of pathogenesis should be useful for the future design of new antiviral strategies against influenza pandemics.


Subject(s)
DEAD-box RNA Helicases/metabolism , Influenza, Human/virology , Interferons/metabolism , Orthomyxoviridae/pathogenicity , Viral Proteins/physiology , A549 Cells , Animals , Dogs , Female , HEK293 Cells , History, 20th Century , Humans , Influenza, Human/epidemiology , Influenza, Human/history , Madin Darby Canine Kidney Cells , Mice , Mice, Inbred BALB C , Orthomyxoviridae/metabolism , Pandemics , Proteolysis , Signal Transduction , U937 Cells , Viral Proteins/metabolism , Virulence/physiology
5.
J Gastroenterol Hepatol ; 37(2): 378-386, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34653281

ABSTRACT

BACKGROUND AND AIM: Besifovir dipivoxil maleate (BSV) was reported to have comparable antiviral efficacy and superior renal and bone safety to tenofovir disoproxil fumarate (TDF) in chronic hepatitis B (CHB) patients. The present study aims to evaluate changes of liver histology and intrahepatic covalently closed circular DNA (cccDNA) levels by BSV treatment in comparison with TDF therapy. METHODS: This is a subset study of the phase 3 trial comparing BSV with TDF. Among them, only CHB patients willing to participate in a histologic evaluation study were enrolled. Liver histologic examination and intrahepatic cccDNA quantification were performed. RESULTS: A total of 46 CHB patients received liver biopsies (BSV, n = 29; TDF, n = 17). After 48 weeks of treatment, virological response rate was comparable between the groups (P = 0.707). Follow-up liver biopsies showed that necroinflammation was significantly improved in the both groups. However, the histological response rate defined as the proportion of subjects whose modified histologic activity index score decreased by ≥ 2 without deterioration in fibrosis was higher in the BSV group than in the TDF group (77.8% vs 36.4%, P = 0.048). The proportion of subjects with Ishak fibrosis score 3 or more decreased from 77.7% to 55.5% in the BSV and that decreased from 72.7% to 45.4% in the TDF group. The intrahepatic cccDNA significantly decreased from baseline after 48 weeks of BSV or TDF treatment (P < 0.001) without intergroup differences (P = 0.349). CONCLUSIONS: The BSV therapy improves hepatic histology and decreases intrahepatic cccDNA in CHB patients.


Subject(s)
DNA, Circular , Guanine/analogs & derivatives , Hepatitis B, Chronic , Liver , Organophosphonates , Antiviral Agents/therapeutic use , DNA, Circular/drug effects , Guanine/therapeutic use , Hepatitis B, Chronic/drug therapy , Humans , Liver/drug effects , Liver/pathology , Organophosphonates/therapeutic use , Treatment Outcome
6.
Int J Mol Sci ; 23(9)2022 Apr 21.
Article in English | MEDLINE | ID: mdl-35562987

ABSTRACT

The ubiquitin system denotes a potent post-translational modification machinery that is capable of activation or deactivation of target proteins through reversible linkage of a single ubiquitin or ubiquitin chains. Ubiquitination regulates major cellular functions such as protein degradation, trafficking and signaling pathways, innate immune response, antiviral defense, and virus replication. The RNA sensor RIG-I ubiquitination is specifically induced by influenza A virus (IAV) to activate type I IFN production. Influenza virus modulates the activity of major antiviral proteins in the host cell to complete its full life cycle. Its structural and non-structural proteins, matrix proteins and the polymerase complex can regulate host immunity and antiviral response. The polymerase PB1-F2 of mutated 1918 IAV, adapts a novel IFN antagonist function by sending the DDX3 into proteasomal degradation. Ultimately the fate of virus is determined by the outcome of interplay between viral components and host antiviral proteins and ubiquitination has a central role in the encounter of virus and its host cell.


Subject(s)
Influenza A virus , Influenza, Human , Orthomyxoviridae Infections , Ubiquitination , Humans , Immunity, Innate , Influenza A virus/metabolism , Influenza, Human/metabolism , Ubiquitin/metabolism , Ubiquitination/physiology , Virus Replication/genetics
7.
Dev Med Child Neurol ; 63(4): 480-487, 2021 04.
Article in English | MEDLINE | ID: mdl-33326122

ABSTRACT

AIM: To investigate the efficacy of a virtual reality rehabilitation system of wearable multi-inertial sensors to improve upper-limb function in children with brain injury. METHOD: Eighty children (39 males, 41 females) with brain injury including cerebral palsy aged 3 to 16 years (mean age 5y 8mo, SD 2y 10mo) were assessed as part of a multicentre, single-blind, randomized controlled trial. The intervention group received a 30-minute virtual reality intervention and a 30-minute session of conventional occupational therapy while the control group received 60 minutes of conventional occupational therapy per session, with 20 sessions over 4 weeks. The virtual reality rehabilitation system consisted of games promoting wrist and forearm articular movements using wearable inertial sensors. The Melbourne Assessment of Unilateral Upper Limb Function-2 (MA-2), Upper Limb Physician's Rating Scale, Pediatric Evaluation of Disability Inventory Computer Adaptive Test, and computerized three-dimensional motion analysis were performed. RESULTS: Both groups (virtual reality, n=40; control, n=38) significantly improved after treatment compared to baseline; however, the virtual reality group showed more significant improvements in upper-limb dexterity functions (MA-2, virtual reality group: Δ=10.09±10.50; control: Δ=3.65±6.92), performance of activities of daily living, and forearm supination by kinematic analysis (p<0.05). In the virtual reality group, children with more severe motor impairment showed significant improvements compared to those with less severe impairment. INTERPRETATION: The virtual reality rehabilitation system used in this study, which consists of wearable inertial sensors and offers intensive, interactive, and repetitive motor training, is effective in children with brain injury. WHAT THIS PAPER ADDS: Both virtual reality rehabilitation and conventional occupational therapy were effective for upper-limb training. Virtual reality training was superior in improving dexterity, performance of activities of daily living, and active forearm supination motion. The effect of virtual reality training was significant in children with more severe motor impairments.


Subject(s)
Brain Injuries/rehabilitation , Cerebral Palsy/rehabilitation , Neurological Rehabilitation/methods , Virtual Reality , Activities of Daily Living , Adolescent , Brain Injuries/physiopathology , Cerebral Palsy/physiopathology , Child , Child, Preschool , Female , Humans , Male , Occupational Therapy , Single-Blind Method , Treatment Outcome , Upper Extremity/physiopathology
8.
BMC Pediatr ; 21(1): 459, 2021 10 19.
Article in English | MEDLINE | ID: mdl-34666730

ABSTRACT

BACKGROUND: There are differences in roles between the more-affected and less-affected upper limb of children with cerebral palsy (CP). However, there is a lack of studies of the relationship between the more-affected limb function and activities of daily living (ADL) in children with CP. Thus, the aim of this prospective cross-sectional study was to investigate the relationship between more-affected upper limb function and ADL in children with CP. METHODS: Children with spastic CP (unilateral CP n = 28, bilateral CP n = 31; 34 males, 25 females; mean age ± SD, 6.8 ± 3.1y [range, 3-14y]) participated in this study. Function of the more-affected upper limb was measured using the Melbourne Assessment of Unilateral Upper limb Function, version 2 (MA2) and the Upper Limb Physician's Rating Scale (ULPRS). Performance of daily living activities was measured using the Pediatric Evaluation of Disability Inventory-Computer Adaptive Test (PEDI-CAT). RESULTS: The range, accuracy and fluency dimension of MA2 and ULPRS total scores were moderately correlated with the daily activity domain (r = 0.47, 0.47, 0.56 for MA2 and r = 0.50 for ULPRS, respectively; P < 0.001) rather than the mobility, social/cognitive, and responsibility domains of the PEDI-CAT. ULPRS scores for elbow extension, supination in extension, supination in flexion, and two-handed function were moderately correlated with the PEDI-CAT daily activity domain (r = 0.44, 0.43, 0.41, and 0.49, respectively; P < 0.01). Finger opening and thumb-in-palm deformity of the ULPRS did not correlate with any PEDI-CAT domain. CONCLUSIONS: The MA2 range, accuracy, and fluency domains (rather than dexterity) had the strongest correlations with the PEDI-CAT daily activity domain. Elbow extension, forearm supination, and two-handed function (rather than wrist and finger movements) of the ULPRS had the strongest correlations with the PEDI-CAT daily activity domain.


Subject(s)
Activities of Daily Living , Cerebral Palsy , Child , Cross-Sectional Studies , Disability Evaluation , Female , Humans , Male , Prospective Studies , Upper Extremity
9.
Sensors (Basel) ; 21(23)2021 Nov 26.
Article in English | MEDLINE | ID: mdl-34883877

ABSTRACT

Poor balance and ataxic gait are major impediments to independent living in ataxic cerebral palsy (CP). Robot assisted-gait training (RAGT) has been shown to improve the postural balance and gait function in children with CP. However, there is no report on the application of RAGT for children with ataxic CP. Here, we report two cases of children with ataxic CP who underwent over-ground RAGT along with conventional therapy for 4 weeks. Outcome measures including the gross motor function measure (GMFM), pediatric balance scale, pediatric reach scale, one-minute walk test, and Timed Up and Go test were assessed before and after the 4-week intervention. Both cases were well adapted to the RAGT system without any significant adverse event. Improvements in the GMFM after RAGT, compared with that in the GMFM, after intensive conventional therapy have been reported previously. It is noteworthy that over-ground RAGT improved areas of the GMFM that did not improve with conventional therapy. In addition, over-ground RAGT with conventional therapy led to improvements in functional balance and walking capacity. These findings suggest that over-ground RAGT is feasible and may be a potential option for enhancing balance and functional walking capacity in children with ataxic CP.


Subject(s)
Cerebral Palsy , Robotics , Ataxia , Child , Exercise Therapy , Gait , Genetic Diseases, Inborn , Humans , Postural Balance , Time and Motion Studies , Walking
10.
Sensors (Basel) ; 21(6)2021 Mar 16.
Article in English | MEDLINE | ID: mdl-33809758

ABSTRACT

The untethered exoskeletal robot provides patients with the freest and realistic walking experience by assisting them based on their intended movement. However, few previous studies have reported the effect of robot-assisted gait training (RAGT) using wearable exoskeleton in children with cerebral palsy (CP). This pilot study evaluated the effect of overground RAGT using an untethered torque-assisted exoskeletal wearable robot for children with CP. Three children with bilateral spastic CP were recruited. The robot generates assistive torques according to gait phases automatically detected by force sensors: flexion torque during the swing phase and extension torque during the stance phase at hip and knee joints. The overground RAGT was conducted for 17~20 sessions (60 min per session) in each child. The evaluation was performed without wearing a robot before and after the training to measure (1) the motor functions using the gross motor function measure and the pediatric balance scale and (2) the gait performance using instrumented gait analysis, the 6-min walk test, and oxygen consumption measurement. All three participants showed improvement in gross motor function measure after training. Spatiotemporal parameters of gait analysis improved in participant P1 (9-year-old girl, GMFCS II) and participant P2 (13-year-old boy, GMFCS III). In addition, they walked faster and farther with lower oxygen consumption during the 6-min walk test after the training. Although participant P3 (16-year-old girl, GMFCS IV) needed the continuous help of a therapist for stepping at baseline, she was able to walk with the platform walker independently after the training. Overground RAGT using a torque-assisted exoskeletal wearable robot seems to be promising for improving gross motor function, walking speed, gait endurance, and gait efficiency in children with CP. In addition, it was safe and feasible even for children with severe motor impairment (GMFCS IV).


Subject(s)
Cerebral Palsy , Robotics , Cerebral Palsy/diagnosis , Child , Child, Preschool , Female , Gait , Humans , Infant , Male , Pilot Projects , Walking
11.
Int J Mol Sci ; 22(4)2021 Feb 05.
Article in English | MEDLINE | ID: mdl-33562603

ABSTRACT

Tenofovir disoproxil fumarate (TDF) has been regarded as the most potent drug for treating patients with chronic hepatitis B (CHB). However recently, viral mutations associated with tenofovir have been reported. Here, we found a CHB patient with suboptimal response after more than 4 years of TDF treatment. Clonal analysis of hepatitis B virus (HBV) isolated from sequential sera of this patient identified the seven previously reported TDF-resistant mutations (CYELMVI). Interestingly, a threonine to alanine mutation at the 301 amino acid position of the reverse-transcriptase (RT) domain, (rtT301A), was commonly accompanied with CYELMVI at a high rate (72.7%). Since the rtT301A mutation has not been reported yet, we investigated the role of this naturally occurring mutation on the viral replication and susceptibility to tenofovir in various liver cells (hepatoma cells as well as primary human hepatocytes). A cell-based phenotypic assay revealed that the rtT301A mutation dramatically impaired the replication ability with meaningful reduction in sensitivity to tenofovir in hepatoma cell lines. However, attenuated viral replication by the rtT301A mutation was significantly restored in primary human hepatocytes (PHHs). Our findings suggest that the replication capability and drug sensitivity of HBV is different between hepatoma cell lines and PHHs. Therefore, our study emphasizes that validation studies should be performed not only in the liver cancer cell lines but also in the PHHs to understand the exact viral fitness under antiviral pressure in patients.


Subject(s)
Hepatitis B virus/drug effects , Hepatocytes/drug effects , Hepatocytes/virology , Tenofovir/pharmacology , Antiviral Agents/pharmacology , Carcinoma, Hepatocellular/genetics , Cell Line, Tumor , Cells, Cultured , Drug Resistance, Viral/genetics , Female , Genes, Viral , Hep G2 Cells , Hepatitis B virus/genetics , Hepatitis B virus/physiology , Hepatitis B, Chronic/drug therapy , Hepatitis B, Chronic/genetics , Hepatitis B, Chronic/virology , Hepatocytes/metabolism , Humans , Liver Neoplasms/genetics , Middle Aged , Point Mutation , RNA-Directed DNA Polymerase/genetics , Reverse Transcriptase Inhibitors/pharmacology , Viral Proteins/genetics , Virus Replication/drug effects , Virus Replication/genetics
12.
Liver Int ; 40(7): 1564-1577, 2020 07.
Article in English | MEDLINE | ID: mdl-32216026

ABSTRACT

BACKGROUND AND AIM: Since polymerase and surface genes overlap in hepatitis B virus (HBV), an antiviral-induced mutation in the polymerase gene may alter the surface antigenicity in patients with chronic hepatitis B (CHB), but this possibility has not been clearly confirmed. This study aimed to determine the drug susceptibility and surface antigenicity of the patient-derived mutants. PATIENTS AND METHODS: Full-length HBV genomes isolated from four entecavir-resistant CHB patients were cloned and sequenced. Around 10 clones of full-length HBV obtained from each patient were analysed and registered in the NCBI GenBank. Representative clones were further characterized by in vitro drug susceptibility and surface antigenicity assays. RESULTS: The rtL180M + rtM204V mutations were common among all the clones analysed. Additionally, the ETV resistance mutations rtT184A/L, rtS202G and rtM250V were found among three patients. Most of the ETV-resistant mutants had amino acid alterations within the known epitopes recognized by T- and B-cells in the HBV surface and core antigens. The in vitro drug susceptibility assay showed that all tested clones were resistant to ETV treatment. However, they were all susceptible to ADV and TDF. More importantly, the rtI169T mutation in the RT domain, led to the sF161L mutation in the overlapping S gene, which decreased in surface antigenicity. CONCLUSIONS: The ETV resistance mutations can affect the antigenicity of the HBsAg proteins due to changes in the overlapping sequence of this surface antigen. Thus, the apparent decline or disappearance of HBsAg needs to be interpreted cautiously in patients with previous or current antiviral resistance mutations.


Subject(s)
Hepatitis B virus , Hepatitis B, Chronic , Antigens, Surface/therapeutic use , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , Drug Resistance, Viral/genetics , Guanine/analogs & derivatives , Guanine/therapeutic use , Hepatitis B virus/genetics , Hepatitis B, Chronic/drug therapy , Humans , Lamivudine/therapeutic use , Mutation
13.
Int J Mol Sci ; 21(3)2020 Jan 31.
Article in English | MEDLINE | ID: mdl-32023898

ABSTRACT

Hepatitis B virus (HBV) infection is a major factor in the development of various liver diseases such as hepatocellular carcinoma (HCC). Among HBV encoded proteins, HBV X protein (HBx) is known to play a key role in the development of HCC. Hepatocyte nuclear factor 4α (HNF4α) is a nuclear transcription factor which is critical for hepatocyte differentiation. However, the expression level as well as its regulatory mechanism in HBV infection have yet to be clarified. Here, we observed the suppression of HNF4α in cells which stably express HBV whole genome or HBx protein alone, while transient transfection of HBV replicon or HBx plasmid had no effect on the HNF4α level. Importantly, in the stable HBV- or HBx-expressing hepatocytes, the downregulated level of HNF4α was restored by inhibiting the ERK signaling pathway. Our data show that HNF4α was suppressed during long-term HBV infection in cultured HepG2-NTCP cells as well as in a mouse model following hydrodynamic injection of pAAV-HBV or in mice intravenously infected with rAAV-HBV. Importantly, HNF4α downregulation increased cell proliferation, which contributed to the formation and development of tumor in xenograft nude mice. The data presented here provide proof of the effect of HBV infection in manipulating the HNF4α regulatory pathway in HCC development.


Subject(s)
Carcinoma, Hepatocellular/virology , Hepatitis B/metabolism , Hepatocyte Nuclear Factor 4/genetics , Hepatocyte Nuclear Factor 4/metabolism , Liver Neoplasms/virology , Trans-Activators/metabolism , Viral Regulatory and Accessory Proteins/metabolism , Animals , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/metabolism , Cell Line, Tumor , Cell Proliferation , Disease Models, Animal , Down-Regulation , Gene Expression Regulation, Neoplastic , Hep G2 Cells , Hepatitis B/genetics , Hepatitis B/virology , Humans , Liver Neoplasms/genetics , Liver Neoplasms/metabolism , Mice , Mice, Nude , Neoplasm Transplantation
14.
J Hepatol ; 70(6): 1093-1102, 2019 06.
Article in English | MEDLINE | ID: mdl-30794889

ABSTRACT

BACKGROUND & AIMS: Tenofovir disoproxil fumarate (TDF) is one the most potent nucleot(s)ide analogues for treating chronic hepatitis B virus (HBV) infection. Phenotypic resistance caused by genotypic resistance to TDF has not been reported. This study aimed to characterize HBV mutations that confer tenofovir resistance. METHODS: Two patients with viral breakthrough during treatment with TDF-containing regimens were prospectively enrolled. The gene encoding HBV reverse transcriptase was sequenced. Eleven HBV clones harboring a series of mutations in the reverse transcriptase gene were constructed by site-directed mutagenesis. Drug susceptibility of each clone was determined by Southern blot analysis and real-time PCR. The relative frequency of mutants was evaluated by ultra-deep sequencing and clonal analysis. RESULTS: Five mutations (rtS106C [C], rtH126Y [Y], rtD134E [E], rtM204I/V, and rtL269I [I]) were commonly found in viral isolates from 2 patients. The novel mutations C, Y, and E were associated with drug resistance. In assays for drug susceptibility, the IC50 value for wild-type HBV was 3.8 ±â€¯0.6 µM, whereas the IC50 values for CYE and CYEI mutants were 14.1 ±â€¯1.8 and 58.1 ±â€¯0.9 µM, respectively. The IC90 value for wild-type HBV was 30 ±â€¯0.5 µM, whereas the IC90 values for CYE and CYEI mutants were 185 ±â€¯0.5 and 790 ±â€¯0.2 µM, respectively. Both tenofovir-resistant mutants and wild-type HBV had similar susceptibility to the capsid assembly modulator NVR 3-778 (IC50 <0.4 µM vs. IC50 = 0.4 µM, respectively). CONCLUSIONS: Our study reveals that the quadruple (CYEI) mutation increases the amount of tenofovir required to inhibit HBV by 15.3-fold in IC50 and 26.3-fold in IC90. These results demonstrate that tenofovir-resistant HBV mutants can emerge, although the genetic barrier is high. LAY SUMMARY: Tenofovir is the most potent nucleotide analogue for the treatment of chronic hepatitis B virus infection and there has been no hepatitis B virus mutation that confers >10-fold resistance to tenofovir up to 8 years. Herein, we identified, for the first time, a quadruple mutation that conferred 15.3-fold (IC50) and 26.3-fold (IC90) resistance to tenofovir in 2 patients who experienced viral breakthrough during tenofovir treatment.


Subject(s)
Antiviral Agents/therapeutic use , Hepatitis B virus/genetics , Hepatitis B, Chronic/drug therapy , Mutation , RNA-Directed DNA Polymerase/genetics , Reverse Transcriptase Inhibitors/therapeutic use , Tenofovir/therapeutic use , Aged , Cell Line, Tumor , Drug Resistance, Viral/genetics , Humans , Male
15.
J Virol ; 92(16)2018 08 15.
Article in English | MEDLINE | ID: mdl-29875248

ABSTRACT

Hepatitis B virus (HBV) infection is a leading cause of liver diseases; however, the host factors which facilitate the replication and persistence of HBV are largely unidentified. Cellular FLICE inhibitory protein (c-FLIP) is a typical antiapoptotic protein. In many cases of liver diseases, the expression level of c-FLIP is altered, which affects the fate of hepatocytes. We previously found that c-FLIP and its cleaved form interact with HBV X protein (HBx), which is essential for HBV replication, and regulate diverse cellular signals. In this study, we investigated the role of endogenous c-FLIP in HBV replication and its underlying mechanisms. The knockdown of endogenous c-FLIP revealed that this protein regulates HBV replication through two different mechanisms. (i) c-FLIP interacts with HBx and protects it from ubiquitin-dependent degradation. The N-terminal DED1 domain of c-FLIP is required for HBx stabilization. (ii) c-FLIP regulates the expression or stability of hepatocyte nuclear factors (HNFs), which have critical roles in HBV transcription and maintenance of hepatocytes. c-FLIP regulates the stability of HNFs through physical interactions. We verified our findings in three HBV infection systems: HepG2-NTCP cells, differentiated HepaRG cells, and primary human hepatocytes. In conclusion, our results identify c-FLIP as an essential factor in HBV replication. c-FLIP regulates viral replication through its multiple effects on viral and host proteins that have critical roles in HBV replication.IMPORTANCE Although the chronic hepatitis B virus (HBV) infection still poses a major health concern, the host factors which are required for the replication of HBV are largely uncharacterized. Our studies identify cellular FLICE inhibitory protein (c-FLIP) as an essential factor in HBV replication. We found the dual roles of c-FLIP in regulation of HBV replication: c-FLIP interacts with HBx and enhances its stability and regulates the expression or stability of hepatocyte nuclear factors which are essential for transcription of HBV genome. Our findings may provide a new target for intervention in persistent HBV infection.


Subject(s)
CASP8 and FADD-Like Apoptosis Regulating Protein/metabolism , Hepatitis B virus/physiology , Host-Pathogen Interactions , Trans-Activators/metabolism , Virus Replication , CASP8 and FADD-Like Apoptosis Regulating Protein/genetics , Gene Knockdown Techniques , Hepatocytes/virology , Humans , Viral Regulatory and Accessory Proteins
16.
Gut ; 67(1): 166-178, 2018 01.
Article in English | MEDLINE | ID: mdl-28341749

ABSTRACT

OBJECTIVE: Interferons (IFNs) mediate direct antiviral activity. They play a crucial role in the early host immune response against viral infections. However, IFN therapy for HBV infection is less effective than for other viral infections. DESIGN: We explored the cellular targets of HBV in response to IFNs using proteome-wide screening. RESULTS: Using LC-MS/MS, we identified proteins downregulated and upregulated by IFN treatment in HBV X protein (HBx)-stable and control cells. We found several IFN-stimulated genes downregulated by HBx, including TRIM22, which is known as an antiretroviral protein. We demonstrated that HBx suppresses the transcription of TRIM22 through a single CpG methylation in its 5'-UTR, which further reduces the IFN regulatory factor-1 binding affinity, thereby suppressing the IFN-stimulated induction of TRIM22. CONCLUSIONS: We verified our findings using a mouse model, primary human hepatocytes and human liver tissues. Our data elucidate a mechanism by which HBV evades the host innate immune system.


Subject(s)
5' Untranslated Regions/genetics , CpG Islands/genetics , Hepatitis B virus/immunology , Interferons/immunology , Minor Histocompatibility Antigens/genetics , Repressor Proteins/genetics , Tripartite Motif Proteins/genetics , Animals , Down-Regulation/genetics , Down-Regulation/immunology , Epigenesis, Genetic , Gene Expression Regulation/immunology , Hepatocytes/metabolism , Humans , Immune Evasion , Liver/metabolism , Methylation , Mice , Minor Histocompatibility Antigens/biosynthesis , Proteome , Repressor Proteins/biosynthesis , Tripartite Motif Proteins/biosynthesis
17.
Scand J Caring Sci ; 32(2): 478-489, 2018 Jun.
Article in English | MEDLINE | ID: mdl-28901568

ABSTRACT

AIM: The concept of shared decision-making is poorly defined and often used interchangeably with related terms. The aim of this study was to delineate and clarify the concept of shared decision-making in the paediatric field. METHOD: Rodgers and Knafl's evolutionary concept analysis was used to delineate and clarify the concept. Following a search of the CINAHL, PubMed and MEDLINE databases and online journals between 1995 and 2016, we included a total of 42 articles that referred to shared decision-making in the paediatric field. RESULTS: The attributes included active participation of the three: parents, children and health professionals; collaborative partnership; reaching a compromise; and common goal for child's health. Antecedents were existing several options with different possible outcomes; substantial decisional conflict; recognising child's health situations that decision-making is needed; and willingness to participate in decision-making. Finally, the consequences included decreased decisional conflict; mutual empowerment; improved child health status; and improved quality of paediatric health care. CONCLUSION: This study provides a theoretical understanding of the concept of shared decision-making in the paediatric field; furthermore, by integrating this concept into paediatric practice, it may help to reduce the gap between theory and practice. The analysis could also provide nursing researchers with insight into paediatric decision-making and establish a foundation to develop future interventions and situation-specific theory for promoting high-quality decision-making in the paediatric field.


Subject(s)
Decision Making , Parents/psychology , Pediatrics/standards , Child , Child, Preschool , Humans , Male , Proof of Concept Study
18.
Hum Brain Mapp ; 38(10): 5292-5306, 2017 10.
Article in English | MEDLINE | ID: mdl-28731515

ABSTRACT

Manifestation of the functionalities from the structural brain network is becoming increasingly important to understand a brain disease. With the aim of investigating the differential structure-function couplings according to network systems, we investigated the structural and functional brain networks of patients with spastic diplegic cerebral palsy with periventricular leukomalacia compared to healthy controls. The structural and functional networks of the whole brain and motor system, constructed using deterministic and probabilistic tractography of diffusion tensor magnetic resonance images and Pearson and partial correlation analyses of resting-state functional magnetic resonance images, showed differential embedding of functional networks in the structural networks in patients. In the whole-brain network of patients, significantly reduced global network efficiency compared to healthy controls were found in the structural networks but not in the functional networks, resulting in reduced structural-functional coupling. On the contrary, the motor network of patients had a significantly lower functional network efficiency over the intact structural network and a lower structure-function coupling than the control group. This reduced coupling but reverse directionality in the whole-brain and motor networks of patients was prominent particularly between the probabilistic structural and partial correlation-based functional networks. Intact (or less deficient) functional network over impaired structural networks of the whole brain and highly impaired functional network topology over the intact structural motor network might subserve relatively preserved cognitions and impaired motor functions in cerebral palsy. This study suggests that the structure-function relationship, evaluated specifically using sparse functional connectivity, may reveal important clues to functional reorganization in cerebral palsy. Hum Brain Mapp 38:5292-5306, 2017. © 2017 Wiley Periodicals, Inc.


Subject(s)
Brain/diagnostic imaging , Brain/physiopathology , Cerebral Palsy/diagnostic imaging , Cerebral Palsy/physiopathology , Adolescent , Adult , Brain/pathology , Brain Mapping , Cerebral Palsy/pathology , Child , Diffusion Tensor Imaging , Female , Humans , Magnetic Resonance Imaging , Male , Neural Pathways/diagnostic imaging , Neural Pathways/pathology , Neural Pathways/physiopathology , Rest , Young Adult
19.
Surg Radiol Anat ; 39(1): 77-83, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27206542

ABSTRACT

PURPOSE: This study describes the nerve entry points and intramuscular nerve branching of the tibialis anterior, providing essential information for therapeutic functional electrical stimulation and botulinum toxin injection. METHODS: One hundred and ten legs from Korean and Thai cadavers were dissected. Ten specimens were harvested and subjected to modified Sihler's staining. RESULTS: The average total length from the lateral malleolus to the fibular head was 32.0 cm (SD 1.9). The nerve entry points were densely distributed between 86.5 and 90.6 % of the reference length, where the first and second nerve entry points were observable. A densely arborizing area of the intramuscular nerve branches was observed at 70-80 % of the reference length. CONCLUSIONS: Based on the results of this study, clinicians can increase the effectiveness of therapeutic functional electrical stimulation and identify the ideal sites for botulinum toxin injection to the tibialis anterior muscle.


Subject(s)
Botulinum Toxins/administration & dosage , Electric Stimulation/methods , Leg/anatomy & histology , Muscle, Skeletal/anatomy & histology , Adult , Aged , Aged, 80 and over , Cadaver , Dissection , Female , Humans , Injections, Intramuscular/methods , Leg/innervation , Male , Middle Aged , Muscle, Skeletal/innervation
20.
J Hepatol ; 64(2): 268-277, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26409214

ABSTRACT

BACKGROUND & AIMS: Cytokines are key molecules implicated in the defense against virus infection. Tumor necrosis factor-alpha (TNF-α) is well known to block the replication of hepatitis B virus (HBV). However, the molecular mechanism and the downstream effector molecules remain largely unknown. METHODS: In this study, we investigated the antiviral effect and mechanism of p22-FLIP (FLICE-inhibitory protein) by ectopic expression in vitro and in vivo. In addition, to provide the biological relevance of our study, we examined that the p22-FLIP is involved in TNF-α-mediated suppression of HBV in primary human hepatocytes. RESULTS: We found that p22-FLIP, a newly discovered c-FLIP cleavage product, inhibited HBV replication at the transcriptional level in both hepatoma cells and primary human hepatocytes, and that c-FLIP conversion to p22-FLIP was stimulated by the TNF-α/NF-κB pathway. p22-FLIP inhibited HBV replication through the upregulation of HNF3ß but downregulation of HNF4α, thus inhibiting both HBV enhancer elements. Finally, p22-FLIP potently inhibited HBV DNA replication in a mouse model of HBV replication. CONCLUSIONS: Taken together, these findings suggest that the anti-apoptotic p22-FLIP serves a novel function of inhibiting HBV transcription, and mediates the antiviral effect of TNF-α against HBV replication.


Subject(s)
CASP8 and FADD-Like Apoptosis Regulating Protein/metabolism , Hepatitis B virus , Tumor Necrosis Factor-alpha , Virus Replication/drug effects , Animals , Antiviral Agents/pharmacology , Cell Line , DNA, Viral/metabolism , Hepatitis B virus/drug effects , Hepatitis B virus/physiology , Hepatocyte Nuclear Factors/metabolism , Hepatocytes/metabolism , Humans , Mice , Models, Animal , Signal Transduction/drug effects , Tumor Necrosis Factor-alpha/metabolism , Tumor Necrosis Factor-alpha/pharmacology
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