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1.
Antiviral Res ; 216: 105662, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37393054

RESUMO

We have reported a lentivector which could effectively induce HBV-specific cytotoxic T lymphocytes (CTLs). Avasimibe is an inhibitor of acetyl-CoA acetyltransferase-1 (ACAT1), and has been shown to enhance T lymphocyte cytotoxicity on tumor cells. However, the role of avasimibe in lentivector-induced HBV-specific T cytotoxic response remains unknown. Based on previous study, we constructed an integration-deficient lentivector LVDC-ID-HBV (harboring HBcAg expression), and the in vitro experiments showed that the combination of avasimibe exhibited better efficacy in inducing HBV-specific CTL responses including cell proliferation, production of cytokines, as well as CTL killing activities. Mechanism experiments showed that increasing cell membrane cholesterol levels by MßCD-coated cholesterol or ACAT1 inhibition efficiently promoted TCR clustering, signaling transduction and immunological synapse formation, thereby mediating augmented CTL responses. Nevertheless, the depletion of plasma membrane cholesterol with MßCD led to obviously decreased CTL responses. The avasimibe-mediated strengthened immune effects were also determined in animal experiments and the results were in agreement with those from the in vitro research. In particular, the in vivo CTL killing activities were identified by the CFSE or BV-labeled splenocyte lysis assay. Moreover, the experiments in HBV transgenic mice showed that the LVDC-ID-HBV plus avasimibe group demonstrated the lowest serum HBsAg and HBV DNA levels, as well as the lowest expression of HBsAg and HBcAg in liver tissues. We concluded that the HBV-specific CTL immune responses could be potentiated by avasimibe through regulating plasma membrane cholesterol levels. Avasimibe may be a potential adjuvant for lentivector vaccine against HBV infection.


Assuntos
Antineoplásicos , Antígenos do Núcleo do Vírus da Hepatite B , Camundongos , Animais , Antígenos do Núcleo do Vírus da Hepatite B/genética , Vírus da Hepatite B/fisiologia , Antígenos de Superfície da Hepatite B/genética , Camundongos Transgênicos , Colesterol/metabolismo
2.
J Med Virol ; 95(4): e28746, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37185848

RESUMO

Hepatitis B virus (HBV) specific T cell immune response plays a vital role in viral clearance. Dendritic cell derived exosomes (Dexs) can activate T cell immunity effectively. Tapasin (TPN) is involved in antigen processing and specific immune recognition. In the present study, we elucidated that Dexs loading TPN (TPN-Dexs) could enhance CD8+ T cell immune response and inhibit virus replication in HBV transgenic mice. T cell immune response and the ability of inhibiting HBV replication were measured in HBV transgenic mice immunized with TPN-Dexs. Meanwhile, CD8+ T cell autophagy and specific T cell immune responses were measured in vitro and vivo, and the mechanisms probably involved in were explored. Purified TPN-Dexs could be taken up into the cytoplasm of DCs and upregulate CD8+ T cell autophagy to enhance specific T cell immune response. In addition, TPN-Dexs could increase the expression of AKT and decrease the expression of mTOR in CD8+ T cells. Further research confirmed that TPN-Dexs could inhibit virus replication and decrease the expression of HBsAg in the liver of HBV transgenic mice. Nevertheless, those also could elicit mice hepatocytes damage. In conclusion, TPN-Dexs could enhance specific CD8+ T cell immune responses via the AKT/mTOR pathway to regulate the autophagy and exert the antiviral effect in HBV transgenic mice.


Assuntos
Exossomos , Vírus da Hepatite B , Camundongos , Animais , Linfócitos T CD8-Positivos , Proteínas Proto-Oncogênicas c-akt , Camundongos Transgênicos , Serina-Treonina Quinases TOR , Apresentação de Antígeno , Autofagia , Camundongos Endogâmicos C57BL
3.
J Gastrointest Oncol ; 13(5): 2472-2484, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36388672

RESUMO

Background: Hepatocellular carcinoma (HCC) is a malignant cancer with rapid progression, vascular invasion, a high recurrence rate and poor prognosis, so it is necessary to take early measures to halt this process. Accumulating evidence indicates that collagen XV (translated by Col15a1) is a basement membrane molecule related to tumour metastasis in several organs. However, the potential function of collagen XV in the liver associated with HCC remains to be further elucidated. Methods: Col15a1 was overexpressed in HepG2 and HCCLM3 cells. CCK8 and colony formation assays were used to assess the capacity of cell proliferation, and Transwell and wound healing assays were utilized to measure cell migration. Western blotting and real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) quantified the protein and mRNA expression levels of genes related to the epithelial-mesenchymal transition (EMT). Then, the effect of collagen XV on tumour metastasis was confirmed in vivo. Finally, we inhibited discoidin domain receptor 1 (DDR1) via DDR1-IN-1 to explore whether the collagen XV interacted with DDR1 to regulate EMT. Results: Patients of HCC with higher expression of Col15a1 showed better survival than patients with low expression. Overexpression of collagen XV in HepG2 and HCCLM3 cells suppressed cell proliferation and migration in vitro and inhibited pulmonary and liver metastasis in vivo. In addition, collagen XV downregulated the DDR1 and transcription factor (Snail, Slug), regulated the EMT markers (Vimentin, E-cadherin, N-cadherin, and MMP9). Furthermore, inhibition of the DDR1 receptor by DDR1-IN-1 suppressed the gene promoting the EMT. Conclusions: Collagen XV functioned as a metastasis inhibitor in HCC by regulating the DDR1-Snail/Slug axis to regulate EMT.

4.
J Viral Hepat ; 29(3): 178-188, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34902200

RESUMO

Early studies have shown that autophagy and TPPII are associated with HBV infection. In this study, adenovirus vector containing TPPII was constructed to immunize HBV transgenic mice in vivo to explore the potential mechanism of autophagy and HBV infection. Our goal is to provide new ideas for immunotherapy of hepatitis B. First, adenovirus vector containing TPPII was constructed. Then, we used adenovirus to immunize HBV transgenic mice and ATG5 knockout HBV transgenic mice. The autophagy of CD8+ T cells was detected by transmission electron microscopy and immunofluorescence electron microscopy, Western blot was used to detect the expression of autophagy LC3 and BECN1, CTL reaction, HBV DNA and HBsAg in serum, HBsAg and HBcAg in liver tissues by immunohistochemistry, to further examine the possible mechanisms involved in autophagy. Adv-HBcAg-TPPII promotes autophagy of CD8+ T lymphocyte, activates CTL response, inhibits HBV DNA replication and HBsAg expression, and PI3K/ Akt /m TOR signalling pathway may be involved in autophagy. This study demonstrates that autophagy of CD8+ T cells was induced by Adv-HBcAg-TPPII and the molecular mechanism may be related to the PI3K/ Akt /m TOR signalling pathway, providing a possible theoretical basis for immunotherapy of hepatitis B.


Assuntos
Vírus da Hepatite B , Hepatite B , Adenoviridae/genética , Animais , Autofagia , Linfócitos T CD8-Positivos/metabolismo , Hepatite B/prevenção & controle , Antígenos do Núcleo do Vírus da Hepatite B/genética , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B/fisiologia , Humanos , Camundongos , Camundongos Transgênicos , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Linfócitos T Citotóxicos
5.
Cancer Manag Res ; 11: 7065-7076, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31440094

RESUMO

BACKGROUND: Homeobox A10 (HOXA10) has been implicated in the development and progression of various human cancers. However, the precise biological functions of HOXA10 in hepatocellular carcinoma (HCC) have not been defined. METHODS: In this study, we examined mRNA expression by quantitative real-time PCR (qRT-PCR) of HOXA10 as well as histone deacetylase (HDAC) and protein levels by Western blot of HOXA10, HDAC1, Cyclin D1, proliferating cell nuclear antigen (PCNA), Survivin and p53 acetylation in HCC tissues and cell lines. We also assessed cell proliferation using Cell Counting Kit-8 (CCK-8) and analyzed cell cycle by flow cytometry. Furthermore, tumor growth of HCC cells in vivo was monitored using the nude mouse xenograft model. Finally, HDAC1 promoter activity and binding in HCC cell lines were detected by luciferase reporter assay and chromatin immunoprecipitation (ChIP), respectively. RESULTS: We uncovered the elevated expression of HOXA10 in HCC tissues compared to adjacent normal liver tissues. RNA interference-mediated knockdown of HOXA10 inhibited HCC cell proliferation both in vitro and in vivo. HOXA10 knockdown also induced cell cycle arrest at G0/G1 phase and apoptosis, which were accompanied with the reduced expression of Cyclin D1, PCNA and Survivin. Notably, HOXA10 knockdown enhanced p53 acetylation (Lys382), which is crucial to the activation of p53. Likewise, HOXA10 knockdown suppressed the transcription of HDAC1, a potential deacetylase for p53. In line with these observations, HDAC1 downregulation abrogated the effects of HOXA10 overexpression on proliferation, cell cycle progression, apoptosis and p53 acetylation, indicating the role of HDAC1 in mediating HOXA10 functions. CONCLUSION: Our results demonstrate that HOXA10 knockdown inhibits proliferation, induces cell cycle arrest and apoptosis in HCC cells by regulating HDAC1 transcription.

6.
Drug Des Devel Ther ; 13: 1289-1300, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31118568

RESUMO

Purpose: Plumbagin is thought to be a bioactive phytochemical drug and exerts an antitumor effect on various cancers. However, few studies focus on the antitumor activity of plumbagin on liver cancer. This study first investigated the antitumor activity of plumbagin on liver cancer and further investigated the molecular mechanism of its antitumor activity against hepatocellular carcinoma, both in vitro and in vivo. Methods: The antiproliferative activity of plumbagin was evaluated through CCK-8, EdU, and colony forming test. The cell cycle and apoptosis were then analyzed by flow cytometer. Western blot was used to detect the expression of apoptosis related protein, SIVA, and mTOR pathway. RNA-seq was performed to determine the gene expression profiles and overexpressed or knocked down SIVA to validate its role in plumbagin's antitumor activity. Regarding animal experiment, a xenograft model in BALB/c nude mice was built using LM3-Luci cells. Then bioluminescence imaging and further immunohistochemistry were performed to study the antitumor activity and the expression of SIVA and mTOR in the plumbagin-treated group. Results: Plumbagin can inhibit proliferation and induce apoptosis of liver cancer cells in vitro. Further experiment demonstrated that plumbagin could inhibit the expression of SIVA and subsequently downregulate the mTOR signaling pathway, and upregulating the expression of SIVA will alleviate the antitumor activity of plumbagin on liver cancer, which confirmed the important role of the SIVA/mTOR signaling pathway in the antitumor activity of plumbagin. In vivo bioluminescence imaging showed a decreased signal in the plumbagin-treated group, and further immunohistochemistry demonstrated that plumbagin could inhibit the SIVA/mTOR signaling pathway in tumor tissues. Conclusion: Our promising results showed that plumbagin could inhibit proliferation and induce apoptosis of hepatic cancer through inhibiting the SIVA/mTOR signaling pathway for the first time, which indicated that plumbagin might be a good candidate against liver cancer.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Proteínas Reguladoras de Apoptose/genética , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/tratamento farmacológico , Regulação para Baixo/efeitos dos fármacos , Neoplasias Hepáticas/tratamento farmacológico , Naftoquinonas/farmacologia , Animais , Proteínas Reguladoras de Apoptose/deficiência , Proteínas Reguladoras de Apoptose/metabolismo , Carcinoma Hepatocelular/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Neoplasias Hepáticas Experimentais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo
7.
Biochem Biophys Res Commun ; 511(4): 889-895, 2019 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-30850165

RESUMO

Tripartite motif-containing protein 7 (TRIM7), which is involved in the biosynthesis of glycogen, has been reported to drive lung tumorigenesis. In the present study, we aimed to examine the expression, roles and underlying molecular mechanisms of TRIM7 in hepatocellular carcinoma (HCC) development. Real-time PCR and immunohistochemical staining were performed to test the expression of TRIM7 in HCC tissues. Cell proliferation, cell cycle and tumorigenicity experiments were conducted to determine the function of TRIM7. The results showed that TRIM7 expression was elevated in human HCC tissues and that TRIM7 expression was significantly associated with tumor size, pTNM stage, serum α-fetoprotein (AFP) concentration, serum hepatitis B virus (HBV) DNA copy number and overall survival (OS) of HCC patients. TRIM7 knockdown inhibited the proliferation of HCC cells in vitro and in vivo. TRIM7 knockdown also induced a G1/S checkpoint in HCC cell lines. Additionally, TRIM7 knockdown led to decreased phosphorylated p38 (p-p38) and increased expression of p53 and p21. Ectopic expression of TRIM7 promoted HCC cell proliferation, cell cycle progression and p38 activation, but not in the presence of the p38 inhibitor SB203580. Moreover, TRIM7 overexpression enhanced the polyubiquitination and degradation of dual specificity phosphatase 6 (DUSP6). DUSP6 overexpression abolished the promotional effect of TRIM7 overexpression on HCC cell proliferation and the activation of p38. Furthermore, HBV X protein (HBx), a protein coded by HBV, was demonstrated to upregulate TRIM7 expression. Collectively, TRIM7 overexpression may contribute to the highly proliferative characteristics of HCC cells, and targeting TRIM7 might be a potential strategy for HCC treatment.


Assuntos
Carcinoma Hepatocelular/metabolismo , Fosfatase 6 de Especificidade Dupla/metabolismo , Neoplasias Hepáticas/metabolismo , Sistema de Sinalização das MAP Quinases , Proteínas com Motivo Tripartido/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Carcinoma Hepatocelular/patologia , Pontos de Checagem do Ciclo Celular , Proliferação de Células , Feminino , Células Hep G2 , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Transdução de Sinais
8.
Cell Cycle ; 17(10): 1220-1234, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30019620

RESUMO

Dendritic cells (DCs) play a predominant role in initiating cell immune responses. Here we generated a DC-targeting lentiviral vector (LVDC-UbHBcAg-LIGHT) and evaluated its capacity to elicit HBV-specific cytotoxic T lymphocyte (CTL) responses. DC-SIGN-mediated specific transduction using this construct was confirmed in DC-SIGN-expressing 293T cells and ex vivo-cultured bone marrow cells. LVDC-UbHBcAg-LIGHT-loaded DCs were highly effective in inducing HBV-specific CTLs. Mechanistic studies demonstrated autophagy blocking led to a significant increase in apoptosis and obvious inhibition of CD8 + T cells entry into S-phase, correspondingly attenuated LVDC-UbHBcAg-LIGHT-loaded DC-induced T cell responses. This observation was supported by accumulation of pro-apoptotic proteins and the main negative cell cycle regulator-CDKN1B that otherwise would be degraded in activated T cells where autophagy preferentially occured. Our findings revealed an important role of autophagy in the activation of T cells and suggested LVDC-UbHBcAg-LIGHT may potentially be used as a therapeutic strategy to combat persistent HBV infection with higher security.


Assuntos
Autofagia , Células Dendríticas/metabolismo , Vetores Genéticos/metabolismo , Vírus da Hepatite B/imunologia , Lentivirus/genética , Linfócitos T Citotóxicos/imunologia , Transdução Genética , Regulação para Cima , Adenina/análogos & derivados , Adenina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Proteína 5 Relacionada à Autofagia/metabolismo , Linfócitos T CD8-Positivos/imunologia , Moléculas de Adesão Celular/metabolismo , Células Dendríticas/efeitos dos fármacos , Engenharia Genética , Antígenos do Núcleo do Vírus da Hepatite B/metabolismo , Humanos , Lectinas Tipo C/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Camundongos Endogâmicos BALB C , Receptores de Superfície Celular/metabolismo , Fase S/efeitos dos fármacos , Linfócitos T Citotóxicos/citologia , Linfócitos T Citotóxicos/efeitos dos fármacos , Linfócitos T Citotóxicos/ultraestrutura , Membro 14 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismo , Ubiquitina/metabolismo , Regulação para Cima/efeitos dos fármacos
9.
J Exp Clin Cancer Res ; 37(1): 116, 2018 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-29898761

RESUMO

BACKGROUND: Many tripartite motif (TRIM) family proteins have been reported to be of great importance in the initiation and progression in hepatocellular carcinoma (HCC). However, the biological role and regulatory mechanism of tripartite motif containing 52 (TRIM52) in HCC development and progression are poorly defined. METHODS: Immunohistochemistry (IHC), quantitative real-time PCR (qRT-PCR) or Western blot analysis was used to detect TRIM52, p21, matrix metalloproteinase 2 (MMP2), protein phosphatase, Mg2+/Mn2+ dependent 1A (PPM1A), p-Smad2/3 and Smad2/3 levels in HCC tissues and cell lines. HCC cell proliferation and cell cycle were measured by Cell Counting Kit-8 (CCK-8) and flow cytometry analysis, respectively. HCC cell migration and invasion were measured by Transwell assay. Tumor growth of HCC cells in vivo was measured using the nude mouse xenograft model. The correlation between TRIM52 and PPM1A was measured by co-immunoprecipitation (Co-IP) and ubiquitination analysis in vitro. RESULTS: TRIM52 was significantly up-regulated in the HCC tissues in comparison with the adjacent non-tumor hepatic tissues. TRIM52 was also up-regulated in HCC cell lines (MHCC-97H and MHCC-97L cells) compared with normal human liver cell line LO2. TRIM52 down-regulation by RNA interfering in MHCC-97H cells enhanced inhibition of cell proliferation, migration and invasion. TRIM52 down-regulation also induced MHCC-97H cells arrest in G0-G1 phase cell cycle and inhibited MHCC-97H cell growth in the nude mice. However, TRIM52 up-regulation in MHCC-97L cells promoted cell proliferation, migration and invasion. Furthermore, TRIM52 down-regulation significantly increased p21 and PPM1A expression, but inhibited MMP2 expression and induced Smad2/3 dephosphorylation in MHCC-97H cells, which were reversed by TRIM52 up-regulation in MHCC-97L cells. TRIM52 was found interacted with PPM1A and TRIM52 down-regulation inhibited the ubiquitination of PPM1A. Importantly, PPM1A up-regulation in MHCC-97L cells significantly suppressed TRIM52-mediated enhancement on cell proliferation, invasion and migration. CONCLUSIONS: Our findings suggest that TRIM52 up-regulation promotes proliferation, migration and invasion of HCC cells through the ubiquitination of PPM1A.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Proteína Fosfatase 2C/metabolismo , Proteínas com Motivo Tripartido/genética , Adulto , Idoso , Animais , Biomarcadores , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Modelos Animais de Doenças , Feminino , Xenoenxertos , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Carga Tumoral , Ubiquitinação
10.
Acta Biochim Biophys Sin (Shanghai) ; 50(2): 181-190, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29340620

RESUMO

Hepatitis B virus (HBV)-specific cytotoxic T lymphocytes (CTLs) play a vital role in viral control and clearance. Recent studies have elucidated that Tapasin, an endoplasmic reticulum chaperone, is a well-known molecule that appears to be essential in peptide-loading process. The Janus kinase/signal transducers and activators of transcription (JAK/STAT) pathway plays an important role in immune response regulation and cytokines secretion. We have previously verified that fusion protein CTP-HBcAg18-27-Tapasin could facilitate the maturation of bone marrow derived dendritic cells and enhance specific CTLs responses in vitro, which might be associated with the activation of JAK/STAT signaling pathway. To further explore whether JAK/STAT signaling pathway participated in specific immune responses mediated by CTP-HBcAg18-27-Tapasin, we suppressed the JAK/STAT pathway with pharmacological inhibitor (AG490) in vivo. Our studies showed that the number of IFN-γ+-CD8+ T cells was decreased significantly compared with other groups after being blocked by AG490. The percentage of IFN-γ+-CD4+ T cells and IL-2-CD4+ T cells was also decreased. Moreover, lower expression levels of Jak2, Tyk2, STAT1, and STAT4 were detected in AG490 group. In addition, the secretion levels of Th1-like cytokines were decreased and a weaker specific T-cell response was observed in AG490 group. Furthermore, the levels of HBV DNA and HBsAg in serum and expression levels of HBsAg and HBcAg in liver tissues were elevated after this pathway was inhibited in HBV transgenic mice. These results demonstrate that the JAK/STAT signaling pathway participates in Th1-oriented immune response induced by CTP-HBcAg18-27-Tapasin and this might provide a theoretical basis for HBV immunotherapy.


Assuntos
Epitopos/imunologia , Janus Quinases/imunologia , Proteínas de Membrana Transportadoras/imunologia , Peptídeos/imunologia , Fatores de Transcrição STAT/imunologia , Linfócitos T Citotóxicos/imunologia , Animais , Citoplasma/imunologia , Citoplasma/metabolismo , Antígenos de Superfície da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/metabolismo , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Imunoterapia/métodos , Janus Quinases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Peptídeos/administração & dosagem , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Tirfostinas/farmacologia
11.
Med Sci Monit ; 23: 5202-5210, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29089476

RESUMO

BACKGROUND Chronic hepatitis B virus (HBV) infection is the major cause of hepatocellular carcinoma (HCC). HBV X protein (HBx) plays a crucial role in the development of HCC. Moreover, many tripartite motif (TRIM) family proteins exert diverse biological functions in hepatocarcinogenesis. However, as a novel member of this family, the specific effect of TRIM52 is still largely obscure. In the present study, we investigated the expression and function of TRIM52 in HBV-associated HCC. MATERIAL AND METHODS Fluorescence quantitative polymerase chain reaction (FQ-PCR) was performed to detect the HBV DNA levels in the peripheral blood of HCC patients. Quantitative real-time PCR (qRT-PCR) and Western blot analysis were performed to detect the expression of TRIM52, HBx, and NF-κB p65. HBx-pcDNA3.1 and TRIM52-shRNA were used to induce HBx ectopic expression and TRIM52 silencing, respectively. Pyrrolidine dithiocarbamate (PDTC) was used to block the activation of NF-κB. Cell proliferation was detected using the Cell Counting Kit-8 (CCK-8) assay. RESULTS TRIM52 expression was up-regulated together with HBx in HBV-associated HCC tissues. Ectopic expression of HBx elevated TRIM52 expression in HepG2 cells. TRIM52 silencing repressed the proliferation of HepG2.2.15 cells. Moreover, NF-κB p65 expression was increased in HCC cell lines. Blocking NF-κB activation with PDTC suppressed TRIM52 expression and attenuated the viability of HepG2.2.15 cells. CONCLUSIONS These findings indicate that TRIM52 can promote cell proliferation and HBx may regulate TRIM52 expression via the NF-κB signaling pathway in HBV-associated HCC.


Assuntos
Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/virologia , Vírus da Hepatite B/fisiologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/virologia , Proteínas com Motivo Tripartido/metabolismo , Carcinoma Hepatocelular/patologia , Proliferação de Células , DNA Viral/metabolismo , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Células Hep G2 , Humanos , Neoplasias Hepáticas/patologia , Transativadores/metabolismo , Fator de Transcrição RelA/metabolismo , Regulação para Cima/genética , Proteínas Virais Reguladoras e Acessórias
12.
Cell Physiol Biochem ; 41(2): 423-438, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28214886

RESUMO

BACKGROUND: Chronic hepatitis B virus (HBV) infection is associated with a weak but specific cellular immune response of the host to HBV. Tripeptidyl peptidaseⅡ (TPPⅡ), an intracellular macromolecule and proteolytic enzyme, plays an important complementary and compensatory role for the proteasome during viral protein degradation and major histocompatibility complex class I antigen presentation by inducing a specific cellular immune response in vivo. Based on a previous study, we aimed to explore the role of MHC class I antigen presentation in vivo and the mechanisms that may be involved. METHODS: In this study, recombinant adenoviral vectors harboring the hepatitis B core antigen (HBcAg) and the TPPII gene were constructed (Adv-HBcAg and Adv-HBcAg-TPPII), and H-2Kd HBV-transgenic BALB/c mice and HLA-A2 C57BL/6 mice were immunized with these vectors, respectively. We evaluated the specific immune responses induced by Adv-HBcAg-TPPII in the HBV transgenic BALB/c mice and HLA-A2 C57BL/6 mice as well as the anti-viral ability of HBV transgenic mice, and we explored the underlying mechanisms. RESULTS: We found that immunization with Adv-HBcAg-TPPII induced the secretion of the cytokines interleukin-2 (IL-2), interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) as well as the activities of IFN-γ-secreting CD8+ T cells and CD4+ T cells. In addition, HBcAg-specific CTL activity in C57/BL mice and HBV transgenic animals was significantly enhanced in the Adv-HBcAg-TPPII group. Furthermore, Adv-HBcAg-TPPII decreased the hepatitis B surface antigen (HBsAg) and HBV DNA levels and the amount of HBsAg and HBcAg in liver tissues. Moreover, Adv-HBcAg-TPPII enhanced the expression of T-box transcription factor (T-bet) and downregulated GATA-binding protein 3 (GATA-3) while increasing the expression levels of JAK2, STAT1, STAT4 and Tyk2. CONCLUSIONS: These results suggested that the JAK/STAT signaling pathway participates in the CTL response that is mediated by the adenoviral vector encoding TPPII. Adv-HBcAg-TPPII could therefore break immune tolerance and stimulate HBV-specific cytotoxic T lymphocyte activity and could have a good therapeutic effect in transgenic mice.


Assuntos
Adenoviridae/genética , Aminopeptidases/metabolismo , Dipeptidil Peptidases e Tripeptidil Peptidases/metabolismo , Vetores Genéticos/metabolismo , Antígenos do Núcleo do Vírus da Hepatite B/metabolismo , Imunidade Celular , Serina Endopeptidases/metabolismo , Alanina Transaminase/sangue , Aminopeptidases/genética , Aminopeptidases/imunologia , Animais , Aspartato Aminotransferases/sangue , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/metabolismo , Citocinas/metabolismo , DNA Viral/sangue , Dipeptidil Peptidases e Tripeptidil Peptidases/genética , Dipeptidil Peptidases e Tripeptidil Peptidases/imunologia , Fator de Transcrição GATA3/metabolismo , Vetores Genéticos/genética , Antígenos do Núcleo do Vírus da Hepatite B/genética , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/genética , Interferon gama/metabolismo , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Fígado/metabolismo , Fígado/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , RNA Mensageiro/metabolismo , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT4/genética , Fator de Transcrição STAT4/metabolismo , Serina Endopeptidases/genética , Serina Endopeptidases/imunologia
13.
J Diabetes Investig ; 8(4): 619-625, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27930871

RESUMO

AIMS/INTRODUCTION: It has not been reported whether chronic hepatitis B virus infection (CHB) is associated with a specific type of diabetes. We sought to investigate the prevalence of CHB status in different diabetes subtypes among a Chinese population. MATERIALS AND METHODS: This was a cross-sectional study. A total of 381 patients with adult-onset autoimmune diabetes, 1,365 patients with type 2 diabetes and 1,365 non-diabetic controls were recruited from June 2005 to February 2014. The exclusion criteria included: (i) hepatitis C virus antibody positive; (ii) hepatic cirrhosis; and (iii) malignant neoplasm and severe renal dysfunction (serum creatinine >450 µmol/L). Patients were grouped as hepatitis B virus-negative and CHB status. RESULTS: Patients with type 2 diabetes had a higher prevalence of CHB than the controls in the overall population (13.5 vs 10.0%, P = 0.004) and among patients with normal hepatic function (13.3 vs 8.8%, P = 0.002). There was no difference in the prevalence of CHB status between patients with adult-onset autoimmune diabetes and the controls. Multiple logistic regression analysis showed that the odds ratio of CHB increased by ~1.5-fold in patients with type 2 diabetes than in the control group after adjustment for age, sex and body mass index, regardless of hepatic function status. CONCLUSIONS: CHB status was more prevalent in patients with type 2 diabetes than in individuals with adult-onset autoimmune diabetes and the controls among the Chinese population. Further research is required to ascertain whether CHB status increases the risk of developing type 2 diabetes, or whether type 2 diabetes, but not adult-onset autoimmune diabetes, increases the risk of CHB.


Assuntos
Diabetes Mellitus Tipo 1/virologia , Diabetes Mellitus Tipo 2/virologia , Hepatite B Crônica/complicações , Adulto , Idoso , Estudos de Casos e Controles , China/epidemiologia , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
14.
Mol Med Rep ; 14(4): 3315-22, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27510296

RESUMO

Recent studies have demonstrated that chronic hepatitis B virus (HBV) infection is associated with reduced antigen­presenting capacity and insufficient cytotoxic T lymphocyte (CTL) production. The molecular chaperone tapasin mediates binding of the transporter associated with antigen processing (TAP), and has an important role in endogenous antigen processing and presentation, and the induction of specific CTL responses. The present study aimed to determine whether tapasin is associated with chronic HBV (CHB) infection. The mRNA expression levels of tapasin were detected in peripheral blood mononuclear cells from 27 patients with CHB, 20 patients with acute HBV (AHB) and 26 healthy controls by reverse transcription­quantitative polymerase chain reaction. In addition, CD8+ T immune responses were evaluated in all groups, and the correlation between tapasin expression and CD8+ responses was analyzed. The results demonstrated that the mRNA expression levels of tapasin were significantly downregulated in patients with CHB compared with in healthy controls and patients with AHB. Furthermore, the apoptotic rate of CD8+ T cells was increased in patients with CHB compared with in the other two groups. The percentage of interferon (IFN)­Î³+CD8+ T cells was reduced in patients with CHB compared with in patients with AHB and healthy controls, and serum cytokine levels (IFN­Î³, interleukin­2 and tumor necrosis factor­α) were generally low in patients with CHB. Furthermore, the mRNA expression levels of tapasin were positively correlated with IFN­Î³ production by CD8+ T cells, and were inversely correlated with the apoptotic ratio of CD8+ T cells. These results indicate that decreased expression of tapasin may be closely associated with CHB, and suggest an important role for tapasin in the pathogenesis of CHB.


Assuntos
Linfócitos T CD8-Positivos/patologia , Regulação para Baixo , Vírus da Hepatite B/imunologia , Hepatite B Crônica/genética , Hepatite B Crônica/patologia , Proteínas de Membrana Transportadoras/genética , Adulto , Apoptose , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Citocinas/sangue , Citocinas/imunologia , Feminino , Regulação da Expressão Gênica , Hepatite B Crônica/sangue , Hepatite B Crônica/imunologia , Humanos , Interferon gama/imunologia , Masculino , Proteínas de Membrana Transportadoras/imunologia , Pessoa de Meia-Idade , RNA Mensageiro/genética , Adulto Jovem
15.
Biomed Res Int ; 2016: 6495793, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27092311

RESUMO

Interleukin-1 (IL-1) family and Kupffer cells are linked with liver regeneration, but their precise roles remain unclear. IL-1 family members are pleiotropic factors with a range of biological roles in liver diseases, inducing hepatitis, cirrhosis, and hepatocellular carcinoma, as well as liver regeneration. Kupffer cells are the main source of IL-1 and IL-1 receptor antagonist (IL-1Ra), the key members of IL-1 family. This systemic review highlights a close association of IL-1 family members and Kupffer cells with liver regeneration, although their specific roles are inconclusive. Moreover, IL-1 members are proposed to induce effects on liver regeneration through Kupffer cells.


Assuntos
Interleucina-1/metabolismo , Células de Kupffer/metabolismo , Hepatopatias/genética , Regeneração Hepática/genética , Humanos , Proteína Antagonista do Receptor de Interleucina 1/genética , Proteína Antagonista do Receptor de Interleucina 1/metabolismo , Interleucina-1/genética , Células de Kupffer/patologia , Hepatopatias/metabolismo , Hepatopatias/patologia , Transdução de Sinais
16.
Immunobiology ; 221(7): 813-21, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26874581

RESUMO

Predominant T helper cell type 1 (Th1) immune responses accompanied by boosted HBV-specific cytotoxic T lymphocyte (CTL) activity are essential for the clearance of hepatitis B virus (HBV) in chronic hepatitis B (CHB) patients. Ubiquitin (Ub) serves as a signal for the target protein to be recognized and degraded through the ubiquitin-proteasome system (UPS). Ubiquitinated hepatitis B core antigen (Ub-HBcAg) has been proved to be efficiently degraded into the peptides, which can be presented by major histocompatibility complex (MHC) class I resulting in stimulating cell-mediated responses. In the present study, lentiviral vectors encoding Ub-HBcAg (LV-Ub-HBcAg) were designed and constructed as a therapeutic vaccine for immunotherapy. HBcAg-specific cellular immune responses and anti-viral effects induced by LV-Ub-HBcAg were evaluated in HBV transgenic mice. We demonstrated that immunization with LV-Ub-HBcAg promoted the secretion of cytokines interleukin-2 (IL-2), interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α), generated remarkably high percentages of IFN-γ-secreting CD8(+) T cells and CD4(+) T cells, and enhanced HBcAg-specific CTL activity in HBV transgenic mice. More importantly, vaccination with LV-Ub-HBcAg could efficiently decreased the levels of serum hepatitis B surface antigen (HBsAg), HBV DNA and the expression of HBsAg and HBcAg in liver tissues of HBV transgenic mice. In addition, LV-Ub-HBcAg could upregulate the expression of T cell-specific T-box transcription factor (T-bet) and downregulate the expression of GATA-binding protein 3 (GATA-3) in spleen T lymphocytes. The therapeutic vaccine LV-Ub-HBcAg could break immune tolerance, and induce potent HBcAg specific cellular immune responses and therapeutic effects in HBV transgenic mice.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Vacinas contra Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Hepatite B/imunologia , Imunoterapia/métodos , Animais , Células Cultivadas , Citotoxicidade Imunológica , Feminino , Vetores Genéticos/genética , Antígenos do Núcleo do Vírus da Hepatite B/química , Antígenos de Histocompatibilidade Classe I/metabolismo , Imunidade Celular , Imunização , Lentivirus/genética , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Proteínas com Domínio T/genética , Proteínas com Domínio T/metabolismo , Ubiquitina/química
18.
Rev. Inst. Med. Trop. Säo Paulo ; 57(3): 273-275, May-Jun/2015. graf
Artigo em Inglês | LILACS | ID: lil-752602

RESUMO

Deep Candida infections commonly occur in immunosuppressed patients. A rare case of a multiple deep organ infection with Candida albicans and spinal tuberculosis was reported in a healthy young man. The 19-year-old man complained of month-long fever and lower back pain. He also had a history of scalded mouth syndrome. Coinfection with Mycobacterium tuberculosis and Candida albicans was diagnosed using the culture of aspirates from different regions. Symptoms improved considerably after antifungal and antituberculous therapy. This case illustrates that infection with tuberculosis might impair the host's immune system and increase the risk of invasive candidiasis in an immunocompetent patient.


As infecções profundas por Candida ocorrem geralmente em pacientes imunossuprimidos. Relatamos caso raro de infecções profundas em múltiplos órgãos por Candida albicans e neuro tuberculose em homem jovem saudável. Um jovem de 19 anos de idade queixou-se de febre e lombalgia há um mês. Relatava ainda histórico de síndrome da boca escaldada. Foi diagnosticada co-infecção por Mycobacterium tuberculosis e Candida albicans em cultura do aspirado de diferentes regiões do organismo. Os sintomas melhoraram significativamente após a terapia antifúngica e antituberculosa. Este caso é apresentado para mostrar que a tuberculose pode prejudicar o sistema imune do hospedeiro e aumentar o risco de candidíase invasiva em paciente imunocompetente.


Assuntos
Humanos , Masculino , Adulto Jovem , Candidíase Invasiva/complicações , Tuberculose da Coluna Vertebral/complicações , Candidíase Invasiva/diagnóstico , Imunocompetência , Tuberculose da Coluna Vertebral/diagnóstico , Tuberculose da Coluna Vertebral/imunologia
19.
Mol Med Rep ; 12(3): 3591-3598, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26004262

RESUMO

Chronic hepatitis B virus (HBV) infection is characterized by functionally impaired type 1 T-helper cell (Thl) immunity and poor HBV­specific T­cell responses. Ubiquitin (Ub), a highly conserved small regulatory protein, commonly serves as a signal for target proteins that are recognized and degraded in proteasomes. The rapid degradation of Ub­mediated antigens results in efficient stimulation of cell­mediated immune responses. Thus, the Ub­HBV core antigen (HBcAg)­cytoplasmic transduction peptide (CTP) fusion protein was designed for specific delivery of a foreign modified antigen to the cytoplasm of antigen­presenting cells. HBV transgenic mice were used to determine whether Ub­HBcAg­CTP would restore HBV­specific immune responses and anti­viral immunity in these animals. The results demonstrated that synthesized Ub­HBcAg­CTP not only significantly increased the levels of interleukin­2 and interferon (IFN)­Î³ compared with those in the HBcAg­CTP, IFN­α, Ub­HBcAg, HBcAg and phosphate­buffered saline groups, but additionally induced the highest IFN­Î³+ CD8+ T­cell numbers and HBV­specific cytotoxic T lymphocyte (CTL) responses, indicating a strong immune response. In addition, enhancement of specific CTL activity provoked by the fusion protein reduced hepatitis B surface antigen (HBsAg) and HBV DNA serum levels and diminished the expression of HBsAg and HBcAg in liver tissue of HBV transgenic mice, suggesting that there was a therapeutic effect. In conclusion, the present study provided evidence that Ub­HBcAg­CTP activated the Th1­dependent immunity, triggered functional T cell responses and subsequently inhibited viral replication in HBV transgenic mice. These observations suggested that the fusion protein may represent an innovative and promising candidate for active immunotherapy during chronic and persistent HBV.


Assuntos
Antígenos do Núcleo do Vírus da Hepatite B/uso terapêutico , Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Hepatite B Crônica/terapia , Linfócitos T Citotóxicos/imunologia , Ubiquitina/uso terapêutico , Vacinas Virais/uso terapêutico , Animais , Antígenos do Núcleo do Vírus da Hepatite B/genética , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Vírus da Hepatite B/genética , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/sangue , Hepatite B Crônica/patologia , Imunidade Celular , Interferon gama/imunologia , Interleucina-2/imunologia , Fígado/imunologia , Fígado/patologia , Fígado/virologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Peptídeos/genética , Peptídeos/imunologia , Peptídeos/uso terapêutico , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Proteínas Recombinantes de Fusão/uso terapêutico , Linfócitos T Citotóxicos/virologia , Ubiquitina/genética , Ubiquitina/imunologia , Vacinação , Vacinas Virais/genética , Vacinas Virais/imunologia
20.
Braz. j. infect. dis ; 19(2): 220-221, Mar-Apr/2015. graf
Artigo em Inglês | LILACS | ID: lil-746509
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