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1.
Virol J ; 20(1): 22, 2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-36750902

RESUMO

BACKGROUND: Patients with type 2 diabetes mellitus (T2DM) have been reported to be more susceptible to 2019 novel coronavirus (2019-nCoV) and more likely to develop severe pneumonia. However, the safety and immunological responses of T2DM patients after receiving the inactivated vaccines are not quite definite. Therefore, we aimed to explore the safety, antibody responses, and B-cell immunity of T2DM patients who were vaccinated with inactivated coronavirus disease 2019 (COVID-19) vaccines. METHODS: Eighty-nine patients with T2DM and 100 healthy controls (HCs) were enrolled, all of whom had received two doses of full-course inactivated vaccines. At 21-105 days after full-course vaccines: first, the safety of the vaccines was assessed by questionnaires; second, the titers of anti-receptor binding domain IgG (anti-RBD-IgG) and neutralizing antibodies (NAbs) were measured; third, we detected the frequency of RBD-specific memory B cells (RBD-specific MBCs) to explore the cellular immunity of T2DM patients. RESULTS: The overall incidence of adverse events was similar between T2DM patients and HCs, and no serious adverse events were recorded in either group. Compared with HCs, significantly lower titers of anti-RBD-IgG (p = 0.004) and NAbs (p = 0.013) were observed in T2DM patients. Moreover, the frequency of RBD-specific MBCs was lower in T2DM patients than in HCs (p = 0.027). Among the 89 T2DM patients, individuals with lower body mass index (BMI) had higher antibody titers (anti-RBD-IgG: p = 0.009; NAbs: p = 0.084). Furthermore, we found that sex, BMI, and days after vaccination were correlated with antibody titers. CONCLUSIONS: Inactivated COVID-19 vaccines were safe in patients with T2DM, but the antibody responses and memory B-cell responses were significantly decreased compared to HCs. TRIAL REGISTRATION NUMBER AND DATE: NCT05043246. September 14, 2021. (Clinical Trials.gov).


Assuntos
Vacinas contra COVID-19 , COVID-19 , Diabetes Mellitus Tipo 2 , Humanos , Anticorpos Neutralizantes , Anticorpos Antivirais , Formação de Anticorpos , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Imunoglobulina G , SARS-CoV-2 , Vacinas de Produtos Inativados , Estudos de Casos e Controles
2.
J Immunol ; 195(7): 3100-9, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26304988

RESUMO

Hepatitis B virus (HBV) persistence is a fundamental process in chronic HBV infection and a key factor in all related liver diseases; however, the mechanisms have yet to be elucidated. We studied the role of TLR2 in HBV persistence using a well-established HBV-carrier mouse model generated by hydrodynamically injecting a phospho-adeno-associated virus/HBV1.2 plasmid into mice. We found that a genetic deficiency in TLR2 improves HBV elimination, whereas activating TLR2 led to more stable HBV persistence, suggesting that TLR2 activation is critical in HBV persistence. Furthermore, we noted that TLR2 activation could inhibit CD8(+) T cell function, causing the exhaustion phenotype in HBV-carrier mice, because TLR2 deficiency might rescue CD8(+) T cell function in a cellular adoptive experiment. TLR2 expression on Kupffer cells (KCs) was upregulated in HBV-carrier mice, which accounts for HBV persistence, because the difference in anti-HBV immunity between HBV-carrier wild-type and Tlr2(-/-) mice did not exist after KC depletion. In addition, similar to TLR2 deficiency, after KC depletion, CD8(+) T cells were more efficiently activated in HBV-carrier mice, leading to rapid HBV elimination. KCs produced more IL-10 upon TLR2 activation in response to direct hepatitis B core Ag stimulation, and the elevated IL-10 inhibited CD8(+) T cell function in HBV-carrier mice, because IL-10 deficiency or anti-IL-10R treatment resulted in CD8(+) T cells with stronger antiviral function. In conclusion, KCs support liver tolerance by inducing anti-HBV CD8(+) T cell exhaustion via IL-10 production after TLR2 activation by hepatitis B core Ag stimulation.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Portador Sadio/imunologia , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Interleucina-10/imunologia , Células de Kupffer/imunologia , Receptor 2 Toll-Like/imunologia , Animais , Células da Medula Óssea/imunologia , Portador Sadio/virologia , Modelos Animais de Doenças , Ativação Enzimática/genética , Vírus da Hepatite B/imunologia , Hepatite B Crônica/virologia , Interleucina-10/biossíntese , Ativação Linfocitária/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Interleucina-10/imunologia , Receptor 2 Toll-Like/genética
3.
Proc Natl Acad Sci U S A ; 110(42): 16993-8, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24089450

RESUMO

The liver plays a critical role in inducing systemic immune tolerance, for example, during limiting hypersensitivity to food allergy and in rendering acceptance of allotransplant or even hepatotropic pathogens. We investigated the unknown mechanisms of liver tolerance by using an established hepatitis B virus (HBV)-carrier mouse model, and found that these mice exhibited an antigen-specific tolerance toward peripheral HBsAg vaccination, showing unenlarged draining lymph node (DLN), lower number of germinal centers (GC), and inactivation of GC B cells and follicular T helper (Tfh) cells. Both in vivo and in vitro immune responses toward HBsAg were suppressed by mononuclear cells from HBV-carrier mice, which were CD4(+) Foxp3(-) type 1 regulatory T (Tr1)-like cells producing IL-10. Using recipient Rag1(-/-) mice, hepatic Tr1-like cells from day 7 of HBV-persistent mice acquired the ability to inhibit anti-HBV immunity 3 d earlier than splenic Tr1-like cells, implying that hepatic Tr1-like cells were generated before those in spleen. Kupffer cell depletion or IL-10 deficiency led to impairment of Tr1-like cell generation, along with breaking HBV persistence. The purified EGFP(+)CD4(+) T cells (containing Tr1-like cells) from HBV-carrier mice trafficked in higher numbers to DLN in recipient mice after HBsAg vaccination, and subsequently inactivated both Tfh cells and GC B cells via secreting IL-10, resulting in impaired GC formation and anti-HB antibody production. Thus, our results indicate Tr1-like cells migrate from the liver to the DLN and inhibit peripheral anti-HBV immunity by negatively regulating GC B cells and Tfh cells.


Assuntos
Centro Germinativo/imunologia , Vírus da Hepatite B/imunologia , Hepatite B/imunologia , Tolerância Imunológica , Fígado/imunologia , Linfócitos T Reguladores/imunologia , Animais , Linfócitos B/imunologia , Linfócitos B/patologia , Movimento Celular/imunologia , Centro Germinativo/patologia , Hepatite B/genética , Hepatite B/patologia , Antígenos de Superfície da Hepatite B/imunologia , Vacinas contra Hepatite B/imunologia , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/imunologia , Interleucina-10/genética , Interleucina-10/imunologia , Células de Kupffer/imunologia , Células de Kupffer/patologia , Fígado/patologia , Fígado/virologia , Camundongos , Camundongos Knockout , Linfócitos T Reguladores/patologia
4.
Hepatology ; 59(2): 443-52, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23929689

RESUMO

UNLABELLED: The liver is considered as a unique lymphoid organ favoring the induction of immune tolerance, rather than immunity. Biologists and clinicians alike have a long-standing interest in how the liver induces systemic immune tolerance, but the mechanism has not yet been well elucidated. Here, we employed hepatitis B virus (HBV)-carrier mice generated by hydrodynamically injecting phosphor-adeno-associated virus/HBV1.2 plasmid as a model for adult chronic HBV infection, which we found were unable to respond to hepatitis B surface antigen vaccination. Humoral tolerance induced in HBV-carrier mice could be transferred into Rag1(-/-) mice, because anti-HBV immunity in immunologically reconstituted Rag1(-/-) mice was inhibited by adoptive transfer of splenocytes from HBV-carrier mice. Humoral tolerance needed at least 7 days for induction and persisted to 3 months after a single HBV plasmid injection. Kupffer cell (KC) depletion or interleukin (IL-10) deficiency broke this humoral tolerance, and exogenous injection of IL-10 could effectively induce this tolerance. CONCLUSION: KCs in HBV-carrier mice expressed more IL-10 and mediated the systemic tolerance induction in an IL-10-dependent manner. This previously undescribed humoral tolerance regarding HBV infection will help to explore new approaches to reverse liver-sustained systemic immune tolerance in liver disease.


Assuntos
Vírus da Hepatite B/imunologia , Hepatite B/imunologia , Tolerância Imunológica/fisiologia , Imunidade Humoral/fisiologia , Interleucina-10/metabolismo , Células de Kupffer/metabolismo , Animais , Portador Sadio/imunologia , DNA Viral/sangue , Modelos Animais de Doenças , Hepatite B/fisiopatologia , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/genética , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Interleucina-10/deficiência , Interleucina-10/genética , Fígado/imunologia , Fígado/patologia , Fígado/virologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
5.
Nutr J ; 14: 67, 2015 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-26155840

RESUMO

Most hepatocellular carcinoma (HCC) patients have complications, including cirrhosis and malnutrition. The efficacy of dietary supplementation with oral branched-chain amino acids (BCAAs) in HCC patients undergoing interventions has not been confirmed. Relevant publications on the efficacy and safety of oral BCAA supplementation for HCC patients undergoing anti-HCC interventions through September, 2014 were searched for identification in the PubMed, Embase, Web of Science, and the Cochrane Library databases. The pooled risk ratio (RR) and standardized mean difference (SMD) were used to assess the supplementation effects. A total of 11 eligible studies (974 patients in total) were evaluated and included in our analysis. Oral BCAA supplementation helped to maintain liver reserve with higher serum albumin (SMD = 0.234, 95% CI: 0.033-0.435, P = 0.022), and lower rates of ascites (RR = 0.545, 95% CI: 0.316-0.938, P = 0.029) and edema (RR = 0.494, 95% CI: 0.257-0.952, P = 0.035) than in the control group. BCAA supplementation seemed to be effective in improving mortality, especially in Child-Pugh class B patients, but the efficacy was not confirmed. Apparent effects were not found in improving HCC recurrence, total bilirubin, ALT, or AST. BCAA supplementation was relatively safe without serious adverse events. BCAA supplementation may be clinically applied in improving liver functional reserve for HCC patients and further improving the quality of life.


Assuntos
Aminoácidos de Cadeia Ramificada/administração & dosagem , Carcinoma Hepatocelular/tratamento farmacológico , Suplementos Nutricionais , Neoplasias Hepáticas/tratamento farmacológico , Aminoácidos de Cadeia Ramificada/efeitos adversos , Carcinoma Hepatocelular/mortalidade , Bases de Dados Factuais , Avaliação Pré-Clínica de Medicamentos , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Neoplasias Hepáticas/mortalidade , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
Gastroenterology ; 144(2): 392-401, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23103614

RESUMO

BACKGROUND & AIMS: We studied the functions of natural killer (NK) cells and the role of the NK cell inhibitory receptor (NKG2A) during hepatitis B virus (HBV) infection in patients and mice. METHODS: We analyzed levels of NKG2A on peripheral blood NK cells from 42 patients with active chronic hepatitis B (CHB), 31 patients with inactive CHB, and 35 healthy volunteers (controls). Five patients with CHB treated with antiviral therapy were also included to evaluate changes in NK cells after HBV titers decreased. We examined the effects of blocking antibodies against NKG2A or its ligand Qa-1 (equivalent to HLA-E in humans) in immunocompetent mice that express HBV from a plasmid and are positive for serum hepatitis B surface antigen (a mouse model of HBV infection). RESULTS: A higher percentage of NK cells from patients with active CHB were positive for NKG2A (38.47%) than from patients with inactive CHB (19.33%; P < .01) or controls (27.96%; P < .05). The percentage of NKG2A(+) cells correlated with serum viral load (r = 0.5457; P < .001). The percentage of NKG2A(+) cells decreased along with HBV load in patients that received antiviral therapy (P < .05). Blocking NKG2A interaction with HLA-E in peripheral NK cells from patients with active CHB increased their cytotoxicity in vitro. NK cells of HBV carrier mice also had higher percentages of NK cells that expressed NKG2A compared with control mice; NKG2A was likely to be up-regulated by production of interleukin-10 by hepatic regulatory CD4(+)CD25(+) T cells. Blocking Qa-1 in these mice promoted viral clearance in an NK cell-dependent manner. CONCLUSIONS: Infection with HBV increases levels of the inhibitory receptor NKG2A on NK cells in mice and humans, and reduces their ability to clear HBV. Reagents designed to block the interaction between NKG2A and HLA-E might be developed to treat CHB infection.


Assuntos
Adenina/análogos & derivados , Anticorpos Anti-Hepatite B/análise , Vírus da Hepatite B/imunologia , Hepatite B Crônica/tratamento farmacológico , Antígenos de Histocompatibilidade Classe I/farmacologia , Células Matadoras Naturais/metabolismo , Subfamília C de Receptores Semelhantes a Lectina de Células NK/antagonistas & inibidores , Organofosfonatos/uso terapêutico , Adenina/uso terapêutico , Adulto , Animais , Antivirais/uso terapêutico , DNA Viral/análise , Modelos Animais de Doenças , Feminino , Citometria de Fluxo , Vírus da Hepatite B/genética , Hepatite B Crônica/sangue , Hepatite B Crônica/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Imuno-Histoquímica , Imunossupressores , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Subfamília C de Receptores Semelhantes a Lectina de Células NK/biossíntese , Subfamília C de Receptores Semelhantes a Lectina de Células NK/imunologia , Carga Viral
7.
Zhonghua Gan Zang Bing Za Zhi ; 22(4): 260-5, 2014 Apr.
Artigo em Zh | MEDLINE | ID: mdl-25173223

RESUMO

OBJECTIVE: To generate a mouse model of chronic hepatitis B (CHB) infection by performing in vivo transduction of hepatitis B virus (HBV) covalently closed circular (ccc)DNA. METHODS: Nude mice were injected with HBV cccDNA at doses of 1.5, 1.0 or 0.5 mug/ml. A control group was generated by giving equal injection volumes of physiological saline. The serum levels of hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) on post-injection days 1 and 3, weeks 1-6, 8 and 10 were assayed by reflection immunoassay. At post-injection week 10, all animals were sacrificed and liver tissues were collected. Copies of HBV DNA in serum and liver tissue were detected by real-time PCR. HBV antigens in liver tissue were detected of by immunohistochemistry. Pathological analysis of liver tissue carried out with hematoxylin-eosin staining. Linear correlation of data was determined by statistical analysis. RESULTS: HBsAg and HBeAg were detected in sera from all three groups of cccDNA-injected mice staring at post-injection day 1 and lasting through week 10. The levels of HBsAg over the 10-week period showed two patterns of increase-decrease;the lowest level was detected at week 4 and the highest level was detected at week 8. In contrast, the levels of HBeAg over the 10-week period showed three patterns of increase-decrease; the lower levels were detected at weeks 2 and 4 and the higher levels at weeks 3 and 6. HBV DNA copies in liver tissues showed a cccDNA dose-dependent descending trend over the 10-week study period (1.5 mug/ml:1.14E+07 ± 6.51E+06 copies/g, 1.0 mug/ml:9.81E+06 ± 9.32E+06 copies/g, and 0.5 mug/ml:3.72E+06 ± 2.35E+06 copies/g; Pearson's r =0.979). HBV DNA copies in sera showed the pattern of 1.0 mug/ml cccDNA more than 1.5 mug/ml cccDNA more than 0.5 mug/ml cccDNA, and in general were higher than those detected in the liver tissues. Liver tissues from all cccDNA-injected mice showed positive immunohistochemistry staining for both HBsAg and HBeAg. HE staining showed that the liver tissues of all cccDNA-injected mice had severe fatty and vacuolar degeneration and less obvious structure of liver lobules (compared to the liver tissues from control mice). CONCLUSION: The CHB mouse model successfully established in this study by in vivo transduction of HBV cccDNA may represent a useful tool to study the pathogenic mechanisms and potential antiviral treatments of human CHB.


Assuntos
DNA Circular/administração & dosagem , DNA Viral/administração & dosagem , Modelos Animais de Doenças , Hepatite B Crônica/virologia , Animais , Antígenos de Superfície da Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/genética , Vírus da Hepatite B/fisiologia , Masculino , Camundongos , Camundongos Nus , Transdução Genética , Replicação Viral
8.
J Am Nutr Assoc ; : 1-10, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39235386

RESUMO

OBJECTIVE: The EAT-Lancet Commission has proposed an EAT-Lancet diet (ELD), also known as a planetary health diet (PHD), which is environmentally sustainable and promotes human health. However, the association between this diet and the risk of hypertension remains unclear. This study aimed to determine whether adherence to ELD was associated with a lower risk of hypertension. METHODS: 11,402 adults without hypertension at baseline from the China Health and Nutrition Survey were included. The PHD score was used to evaluate ELD adherence, with higher scores reflecting better compliance. Cox proportional hazards regression analysis was utilized to estimate the hazard ratio (HR) with a 95% confidence interval (CI). Additionally, a subgroup analysis was performed to identify the possible effect modifiers, and a mediation analysis was conducted to explore the mediation effects of anthropometric measurements on the association between ELD and hypertension. RESULTS: A total of 3993 participants (35%) developed hypertension during 93,058 person-years of follow-up. In the covariate-adjusted model, hypertension risk was reduced in the highest quartile participants compared to the lowest quartile of the PHD score (adjusted HR: 0.79, 95%CI: 0.71-0.87; P-trend < 0.001), which remained significant after sensitivity analysis. Notably, the association was also observed in isolated systolic hypertension, isolated diastolic hypertension, and systolic-diastolic hypertension. Subgroup analysis revealed that the inverse association between the PHD score and hypertension risk was more pronounced in nonsmokers and high-sodium intake consumers than in smokers and low-sodium consumers (P-interaction < 0.05). Additionally, mediation analysis revealed that 23.3% of the association between the PHD score and hypertension risk was mediated by the waist-to-height ratio. CONCLUSION: Our findings suggest that a higher adherence to ELD is associated with a lower risk of hypertension. These results emphasize that ELD may serve as a potential strategy to prevent hypertension.

9.
JMIR Public Health Surveill ; 10: e49285, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38363593

RESUMO

BACKGROUND: The worldwide spread of monkeypox (mpox) has witnessed a significant increase, particularly in nonendemic countries. OBJECTIVE: We aimed to investigate the changing clinical symptoms associated with mpox from 1970 to 2023 and explore their interrelations. METHODS: In this systematic review and meta-analysis, 3 electronic databases were searched for English peer-reviewed studies conducted from January 1970 to April 2023 that reported any symptoms among confirmed mpox cases. We categorized the mpox epidemics into 3 periods: 1970-2002 (period 1, within the African region), 2003-2021(period 2, epidemics outside Africa), and 2022-2023 (period 3, worldwide outbreak). Following PRISMA guidelines, a meta-analysis was performed to estimate the pooled prevalence for each symptom. The correlation among symptoms was analyzed and visualized using network analysis. RESULTS: The meta-analysis included 61 studies that reported 21 symptoms in 720 patients from period 1, 39 symptoms in 1756 patients from period 2, and 37 symptoms in 12,277 patients from period 3. The most common symptom among patients from all 3 periods was rash (period 1: 92.6%, 95% CI 78.2%-100%; period 2: 100%, 95% CI 99.9%-100%; and period 3: 94.8%, 95% CI 90.9%-98.8%), followed by lymphadenopathy (period 1: 59.8%, 95% CI 50.3%-69.2%; period 2: 74.1%, 95% CI 64.2%-84.1%; and period 3: 61.1%, 95% CI 54.2%-68.1%). Fever (99%, 95% CI 97%-100%), enlarged lymph nodes (80.5%, 95% CI 75.4%-85.0%), and headache (69.1%, 95% CI 4%-100%) were the main symptoms in period 1, with a significant decrease in period 3: 37.9%, 31.2%, and 28.7%, respectively. Chills/rigors (73.3%, 95% CI 60.9%-85.7%), fatigue (68.2%, 95% CI 51.6%-84.8%), and dysphagia/swallowing difficulty (61.2%, 95% CI 10.5%-100%) emerged as primary new symptoms in period 2 and decreased significantly in period 3. Most other symptoms remained unchanged or decreased in period 3 compared to the former 2 periods. Nausea/vomiting had the highest degree of correlation (with 13 symptoms) and was highly positively correlated with lymphadenopathy (r=0.908) and conjunctivitis (r=0.900) in period 2. In contrast, rash and headache were 2 symptoms with the highest degree of correlation (with 21 and 21 symptoms, respectively) in period 3 and were highly positively correlated with fever (r=0.918 and 0.789, respectively). CONCLUSIONS: The manifestation of symptoms in patients with mpox has become more diverse, leading to an increase in their correlation. Although the prevalence of rash remains steady, other symptoms have decreased. It is necessary to surveil the evolving nature of mpox and the consequential changes in clinical characteristics. Epidemic countries may shift their focus on the potential association among symptoms and the high synergy risk. TRIAL REGISTRATION: PROSPERO Registration: CRD42023403282; http://tinyurl.com/yruuas5n.


Assuntos
Mpox , Humanos , Mpox/epidemiologia , Epidemias , Metanálise em Rede , Avaliação de Sintomas/estatística & dados numéricos
10.
Int Immunopharmacol ; 114: 109567, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36529024

RESUMO

CD39-mediated inhibition of natural killer (NK) cell activity has been demonstrated, but the characteristics of CD39+ NK cells in humans are not known. We investigated the characteristics of human circulating CD39+ NK cells. In healthy donors, the proportion of circulating CD39+ NK cells in total NK cells was relatively low compared with that of CD39- NK cells. Nonetheless, a higher proportion of CD39+ NK cells expressed CD107a. Similarly, a higher proportion of CD39+ NK cells expressed CD107a in patients with hepatitis B virus or patients with hepatocellular carcinoma. Stimulation with NK-sensitive K562 cells or interleukin (IL)-12/IL-18 activated CD39+ NK cells to express higher levels of CD107a, IFN-γ and TNF-α, relative to CD39- NK cells. Importantly, IL-15 induced the generation of CD39+ NK cells. In contrast, A2A adenosine receptor (A2AR) ligation suppressed the generation of CD39+ NK cells by inhibiting IL-15 signaling. These data for the first time demonstrated that A2AR counteracts IL-15-induced generation of human CD39+ NK cells, which have a stronger cytotoxicity than CD39- NK cells. IL-15-induced human CD39+ NK cells might be better choice for immunotherapy based on adoptive transfer of NK cells.


Assuntos
Interleucina-15 , Células Matadoras Naturais , Humanos , Citotoxicidade Imunológica , Receptor A2A de Adenosina/metabolismo
11.
Liver Int ; 32(8): 1306-14, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22380514

RESUMO

BACKGROUND: Interleukin-15 (IL-15) is a pleiotropic cytokine known to modulate both innate and adaptive immunity. It is suggested that IL-15 may play an important role in the regulation of immune response to hepatitis B virus (HBV). AIMS: We investigated whether IL-15 could modulate the immune response to HBV. METHODS: A mouse model for HBV tolerance was established by hydrodynamical injection of pAAV/HBV1.2 plasmid into C57BL/6 mice. This HBV-carrier mouse was simultaneously hydrodynamically injected with either an IL-15-expression plasmid pLIVE-IL-15 or a mock control vector pLIVE-EGFP. The serum levels of HBsAg and HBeAg were measured by radioimmunoassay. RESULTS: Hydrodynamic injection of the plasmid pLIVE-IL-15 resulted in sustained high level of IL-15 in mouse serum, along with the markedly decreased serum HBsAg and HBeAg titres and liver HBV DNA levels. IL-15 also induced anti-HBV activity in T cell- and B cell-deficient Rag1(-/-) mice. Interestingly, despite an increase in NK cell numbers in both spleen and liver of IL-15 treated mice, the anti-HBV effect of IL-15 was neither dependent on presence of NK cells nor on production of IFN-γ. Furthermore, IL-15 could exert anti-HBV function independent of the common IL-2γ(c) R. Lastly, we found that IFN-ß expression in the liver and serum was significantly up-regulated by liver expression of IL-15, and blockade of IFN-ß function abrogated the anti-HBV activity of IL-15. CONCLUSIONS: Liver over-expression of IL-15 may suppress HBV replication in an IFN-ß-dependent manner.


Assuntos
Vírus da Hepatite B/imunologia , Hepatite B/imunologia , Interferon beta/imunologia , Interleucina-15/genética , Interleucina-15/imunologia , Animais , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linfócitos B/virologia , Modelos Animais de Doenças , Proteínas de Homeodomínio/genética , Tolerância Imunológica/imunologia , Interferon beta/metabolismo , Interferon gama/genética , Subunidade gama Comum de Receptores de Interleucina/genética , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Células Matadoras Naturais/virologia , Fígado/imunologia , Fígado/virologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Plasmídeos/farmacologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Linfócitos T/virologia , Replicação Viral/imunologia
12.
Antiviral Res ; 205: 105385, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35917968

RESUMO

Natural killer (NK) cells play a crucial role in the control of human viral infections but their activity is significantly impaired in patients infected with chronic hepatitis B (CHB). The mechanism that contributes to NK cell dysfunction in CHB needs further elucidation. In this study, we analyzed the expression and function of the novel inhibitory receptor immunoglobulin-like transcript-2 (ILT2) on NK cells from 131 CHB patients and 36 healthy controls. We observed that ILT2 expression on circulating CD56dimCD16+NK cells was increased in immune-tolerant, immune-active and HBeAg-negative hepatitis patients compared with inactive carriers and controls. The frequency of ILT2+CD56dimNK cells was positively correlated with serum viral load in immune-tolerant patients. The percentage of ILT2+CD56dimNK cells decreased along with HBV load in CHB patients who received antiviral therapy. Functional analysis showed that ILT2+CD56dimNK cells in CHB patients had significantly reduced degranulation and IFN-γ production. Upregulation of ILT2 was associated with high levels of apoptosis in CD56dimCD16+NK cells from CHB patients. ILT2 blockade was shown to increase the cytotoxicity and IFN-γ production of CD56dimNK cells in some CHB patients. Finally, ILT2 was found to be moderately upregulated by TGF-ß1, which was increased in immune-tolerant, immune-active and HBeAg-negative hepatitis patients. Our results show that chronic HBV infection increases the levels of the inhibitory receptor ILT2 on CD56dimNK cells and inhibits their functions, providing a new mechanism of NK-cell disability in CHB patients.


Assuntos
Antígenos CD/imunologia , Hepatite B Crônica , Receptor B1 de Leucócitos Semelhante a Imunoglobulina/imunologia , Antígeno CD56/imunologia , Proteínas Ligadas por GPI/imunologia , Antígenos E da Hepatite B , Vírus da Hepatite B , Humanos , Interferon gama/metabolismo , Células Matadoras Naturais , Receptores de IgG/imunologia
13.
Front Immunol ; 13: 1019365, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36311752

RESUMO

The inflammasome has been linked to diverse inflammatory and metabolic diseases, and tight control of inflammasome activation is necessary to avoid excessive inflammation. Kynurenic acid (KA) is a tryptophan metabolite in the kynurenine pathway. However, the roles and mechanisms of the regulation of inflammasome activation by KA have not yet been fully elucidated. Here, we found that KA suppressed caspase-1 activation and IL-1ß production in macrophages by specifically inhibiting canonical and noncanonical activation of the NLRP3 inflammasome. Mechanistically, KA reduced calcium mobilization through G-protein receptor 35 (GPR35), resulting in reduced mitochondrial damage and decreased mtROS production, thus blocking NLRP3 inflammasome assembly and activation. Importantly, KA prevented lipopolysaccharide-induced systemic inflammation, monosodium urate-induced peritoneal inflammation, and high-fat diet-induced metabolic disorder. Thus, KA ameliorated inflammation and metabolic disorders by blocking calcium mobilization-mediated NLRP3 inflammasome activation via GPR35. Our data reveal a novel mechanism for KA in the modulation of inflammasome activation and suggest that GPR35 might be a promising target for improving NLRP3 inflammasome-associated diseases by regulating calcium mobilization.


Assuntos
Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Humanos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Ácido Cinurênico/farmacologia , Caspase 1/metabolismo , Cálcio/metabolismo , Interleucina-1beta/metabolismo , Proteínas de Transporte/metabolismo , Inflamação/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Receptores Acoplados a Proteínas G/metabolismo
14.
Oncoimmunology ; 10(1): 2002068, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34777920

RESUMO

CD3+CD56+ NKT-like cells play pivotal roles in the anti-tumor immune defense response. However, little is known regarding circulating NKT-like cells in patients with primary hepatocellular carcinoma (HCC). In the present study, we demonstrate that circulating NKT-like cells in HCC patients are functionally impaired and anti-PD-1 blockade improves their anti-tumor potency. Circulating NKT cells were mainly comprised of CD8+ T cells. The frequencies and absolute counts of circulating NKT-like cells were comparable between HCC patents compared to healthy donors. NKT-like cells in HCC patients were impaired in their production of TNF-α and IFN-γ as well as cytotoxicity. The level of activating receptor NKG2D was significantly decreased on NKT-like cells in HCC patients. In contrast, the expression of inhibitory receptors PD-1, Tim-3, and CTLA-4 were markedly increased on NKT-like cells in HCC patients. Meanwhile, the expression of PD-L1 was also upregulated on NKT-like cells in HCC patients. In detail, PD-1+ NKT-like cells expressed lower levels of NKG2D, higher levels of Tim-3, and CTLA-4, and less IFN-γ when compared with PD-1- NKT-like cells. Importantly, PD-1 blocked with anti-PD-1 antibody effectively improved the effector function of NKT-like cells from HCC patients or healthy donors. Our findings unveil the functional characterization of NKT-like cells in HCC patients and provide the potential targets to improve their function, which might benefit the optimization of HCC immunotherapy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Células T Matadoras Naturais , Linfócitos T CD8-Positivos , Carcinoma Hepatocelular/tratamento farmacológico , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Receptor de Morte Celular Programada 1
15.
Front Immunol ; 12: 603192, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33746949

RESUMO

Increasing evidence suggests that NODs are involved in liver diseases; however, the underlying mechanisms remain obscure. In the present study, we analyzed the effect of NOD1 agonist pretreatment on acute liver failure induced by lipopolysaccharide (LPS) in D-galactosamine (D-GalN)-sensitized mice. We found that pretreatment with the NOD1 agonist markedly reduced LPS/D-GalN-induced mortality, elevation of serum ALT levels, and hepatocyte apoptosis. The protective effect of NOD1 agonist was independent of tumor necrosis factor (TNF)-α inhibition. NOD1 agonist pretreatment also attenuated TNF-α/D-GalN-induced apoptotic liver damage. The anti-apoptotic protein A20 expression was more pronounced in NOD1 agonist pretreated mice than in controls, and knockdown of A20 abrogated the protective effect of NOD1 agonist on LPS/D-GalN-induced liver injury and hepatocyte apoptosis. Further experiments showed that NOD1 agonist-induced A20 upregulation required the presence of kupffer cells and TNF-α. Taken together, our data strongly indicate that NOD1 is involved in the regulation of liver injury and could be a potential therapeutic target for liver diseases.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Galactosamina/toxicidade , Hepatócitos/imunologia , Lipopolissacarídeos/toxicidade , Proteína Adaptadora de Sinalização NOD1/agonistas , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/imunologia , Regulação para Cima/efeitos dos fármacos , Animais , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/imunologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Hepatócitos/patologia , Masculino , Camundongos , Camundongos Knockout , Proteína Adaptadora de Sinalização NOD1/genética , Proteína Adaptadora de Sinalização NOD1/imunologia , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/genética , Regulação para Cima/genética , Regulação para Cima/imunologia
16.
Front Immunol ; 11: 582292, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33381113

RESUMO

Chronic hepatitis B virus (HBV) infection is one of the main causes of liver diseases, of which the natural history and clinical outcomes are associated with the role of B cells. As humoral immune cells, B cells play a critical role in the process of anti-HBV antibody production. In addition, some studies have also characterized other B cell subsets involved in antigen presentation and regulating the immune response beyond antibody secretion. However, not all B cell subsets play a positive role in the immune response to chronic HBV infection, and various B cell subsets jointly mediate persistent HBV infection, tolerance, and liver damage. Thus, we further sought to elucidate the multiple functions of B cells to gain novel insight into the understanding of chronic hepatitis B (CHB) pathogenesis. We also reviewed the current immunotherapies targeting B cells to explore novel therapeutic interventions for the treatment of chronic HBV infection.


Assuntos
Subpopulações de Linfócitos B/imunologia , Linfócitos B/imunologia , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/imunologia , Imunoterapia/métodos , Fígado/metabolismo , Animais , Anticorpos Antivirais/metabolismo , Formação de Anticorpos , Humanos , Tolerância Imunológica , Imunomodulação , Fígado/patologia
17.
Hepatol Int ; 14(3): 338-346, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32130674

RESUMO

BACKGROUND: Hepatitis B is a serious global health problem. Mother-to-child transmission (MTCT) of hepatitis B virus (HBV) is a major risk factor in the endemicity of HBV infection. Oral antiviral drugs are recommended to highly viremic mothers to decrease MTCT of HBV. The present network analysis compared the efficacy of available treatments to prevent the MTCT of HBV. METHODS: The electronic databases of PubMed, Embase, Web of Science, Scopus, and Wanfang data were searched for eligible studies. Pair-wise meta-analysis and Bayesian network analysis were applied to compare the efficacy of antiviral drugs. RESULTS: Seventy-five studies involving 12,740 pregnant females were eligible for analysis. On pair-wise analysis, lamivudine (OR 0.15, 95% CI 0.09-0.25, I-squared = 0%), telbivudine (OR 0.07, 95% CI 0.05-0.10, I-squared = 0%) and tenofovir (OR 0.07, 95% CI 0.04-0.13, I-squared = 0%) significantly decreased the MTCT rate. Results of multiple comparisons with ranking probability based on Bayesian analysis showed that tenofovir (SUCRA = 96.83%) appeared more effective than the two other drugs. CONCLUSION: In addition to active and passive immunoprophylaxis, lamivudine, telbivudine and tenofovir in highly viremic mothers can further decrease MTCT of HBV. Based on direct and indirect evidence, tenofovir appears to be more effective than the two other drugs in the prevention of HBV MTCT.


Assuntos
Antivirais , Hepatite B Crônica , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Antivirais/classificação , Antivirais/farmacologia , Feminino , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/transmissão , Humanos , Metanálise em Rede , Gravidez , Resultado do Tratamento
18.
Int J Mol Med ; 42(1): 547-556, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29620142

RESUMO

The aim of the present study was to investigate the function and mechanism of microRNA­497 (miRNA/miR­149) in the regulation of cerebral infarction. In patients with cerebral infarction, the serum of microRNA­497 expression was upregulated compared with that in healthy controls. In N2A cells, overexpression of miR­497 induced cell proliferation, decreased apoptosis and caspase­3 and caspase­9 activities, and suppressed Bax protein expression compared with that in the negative control group. Overexpression of miR­497 reduced inflammation factors, and suppressed the Toll­like receptor 4 (TLR4), myeloid differentiation primary response protein MyD88 (MyD88) and nuclear factor­κB (NF­κB) protein expression of the N2A cells. Next, miR­497 overexpression suppressed the protein expression of interleukin­1 receptor associated kinase (IRAK1) and phosphorylated cyclic AMP response element binding protein (p-CREB) in the N2A cells. Following miR­497 overexpression, TLR4 inhibitor was found to suppress the inflammation factors, suppress the TLR4, MyD88 and NF­κB protein expression, and reduce the IRAK1 and p­CREB protein expression of the N2A cells. Lastly, CREB inhibitor also suppressed p­CREB protein expression, induced cell proliferation, decreased apoptosis and caspase­3 and caspase­9 activities, and suppressed Bax protein expression in the N2A cells following miR­497 overexpression. Taken together, these data demonstrated that miR­497 attenuated cerebral infarction in patients by regulating the TLR4 and CREB signaling pathways.


Assuntos
Infarto Cerebral/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , MicroRNAs/metabolismo , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo , Idoso , Animais , Apoptose/genética , Caspase 3/metabolismo , Caspase 9/metabolismo , Proliferação de Células , Infarto Cerebral/sangue , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/antagonistas & inibidores , Humanos , Mediadores da Inflamação/metabolismo , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Masculino , Camundongos , MicroRNAs/sangue , MicroRNAs/genética , Pessoa de Meia-Idade , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Fosforilação , Proteína X Associada a bcl-2/metabolismo
20.
Int Immunopharmacol ; 62: 59-66, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29990695

RESUMO

BACKGROUND AND AIMS: Much evidence indicates that the soluble antigens secreted by hepatitis B virus (HBV) inhibit the function of the immune system. The aim of this study is to investigate, after treatment with nucleoside (acid) analogs (NAs) and the inhibition of viral replication, whether the immune systems of patients with a peripheral blood HBV-DNA level <1000 IU/mL, hepatitis B e antigen (HBeAg) disappearance, and a decrease in hepatitis B surface antigen (HBsAg) levels could be reconstructed. METHODS: The frequency and phenotype of circulating natural killer (NK) cells, dendritic cells (DCs), T-helper (Th) cells, regulatory T (Treg) cells, CD4+, CD8+ T cells, T follicular helper (Tfh) cells and B cells subtypes were tested by flow cytometry in chronic hepatitis B (CHB) patients and healthy controls (HCs). The levels of HBV-related serum HBsAg, HBeAg, HBV-DNA load, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were determined. RESULTS: Regarding the innate immune system, an increased frequency of CD56dim NK cells was found in the therapeutic response (TR) group compared with that in the immune-active phase (IA) group. Additionally, regarding the adaptive immune system, the Th17/CD4+CD25+CD127dimTreg ratio was reduced in the TR group. Additionally, the frequency of CD40L+CXCR5+CD4+T cells and CD40+CD19+CD27+CD38+B cells was significantly higher than that of HCs, while that of PDL1+CD19+ B cells was lower. Furthermore, the frequencies of CTLA4+CD4+T cells and CTLA4+CD8+T cells in patients with CHB were significantly higher than those in HCs. CONCLUSION: After NA treatment and the inhibition of viral replication, circulating CD56dim NK cells and the balance of Th17/Treg can be recovered. Restoring circulating CD56dim NK cells and the Th17/Treg balance may help reduce HBsAg levels in patients.


Assuntos
Antivirais/uso terapêutico , Antígeno CD56/sangue , Guanina/uso terapêutico , Antígenos de Superfície da Hepatite B/sangue , Hepatite B Crônica/tratamento farmacológico , Células Matadoras Naturais/imunologia , Linfócitos T Reguladores/citologia , Células Th17/citologia , Adulto , Estudos de Casos e Controles , DNA Viral/sangue , Feminino , Guanina/análogos & derivados , Antígenos de Superfície da Hepatite B/imunologia , Antígenos E da Hepatite B , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/imunologia , Hepatite B Crônica/sangue , Hepatite B Crônica/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Resultado do Tratamento , Carga Viral , Adulto Jovem
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