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1.
J Clin Invest ; 1302019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31408442

RESUMO

Checkpoint blockade antibodies have been approved as immunotherapy for multiple types of cancer, but the response rate and efficacy are still limited. There are few immunogenic cell death (ICD)-inducing drugs available that can kill cancer cells, enhance tumor immunogenicity, increase the in vivo immune infiltration, and thereby boosting a tumor response to immunotherapy. So far, the ICD markers have been identified as the few immuno-stimulating characteristics of dead cells, but whether the presence of such ICD markers on tumor cells translates into enhanced antitumor immunity in vivo is still investigational. To identify anticancer drugs that could induce tumor cell death and boost T cell response, we performed drug screenings based on both an ICD reporter assay and T cell activation assay. We identified that teniposide, a DNA topoisomerase II inhibitor, could induce high mobility group box 1 (HMGB1) release and type I interferon signaling in tumor cells, and teniposide-treated tumor cells could activate antitumor T cell response both in vitro and in vivo. Mechanistically, teniposide induced tumor cell DNA damage and innate immune signaling including NF-κB activation and STING-dependent type I interferon signaling, both of which contribute to the activation of dendritic cells and subsequent T cells. Furthermore, teniposide potentiated the antitumor efficacy of anti-PD1 on multiple types of mouse tumor models. Our findings showed that teniposide could trigger tumor immunogenicity, and enabled a potential chemo-immunotherapeutic approach to potentiate the therapeutic efficacy of anti-PD1 immunotherapy.

2.
Mater Sci Eng C Mater Biol Appl ; 103: 109777, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31349400

RESUMO

Tuberculosis (TB), caused by M.tuberculosis (Mtb), has become a top killer among infectious diseases. Enhancing the ability of anti-TB drugs to kill intracellular Mtb in host cells remains a big challenge. Here, an innovative nano-system was developed to increase drug delivery and Mtb-killing efficacy in Mtb-infected macrophages. We employed mannose surface decoration to develop mannosylated and PEGylated graphene oxide (GO-PEG-MAN). Such nano-platform exhibited increased uptake by macrophages via mannose receptor-mediated endocytosis in vitro. Interestingly, drug-loaded GO-PEG-MAN was preferentially up-taken by mannose receptor-expressing mucosal CD14+ macrophages isolated from Mtb-infected rhesus macaques than drug-loaded GO-PEG. Consistently, the drug concentration was also significantly higher in macrophages than that in T and B cells expressing no or low mannose receptor, implicating a useful macrophage/mannose receptor-targeted drug-delivery system relevant to the in vivo settings. Concurrently, rifampicin-loaded GO-PEG-MAN (Rif@GO-PEG-MAN) significantly increased rifampicin uptake, inducing long-lasting higher concentration of rifampicin in macrophages. Such innovative Rif@GO-PEG-MAN could readily get into the lysosomes of the Mtb host cells, where rifampicin underwent an accelerated release in acidic lysosomic condition, leading to explosive rifampicin release after cell entry for more effective killing of intracellular Mtb. Most importantly, Rif@GO-PEG-MAN-enhanced intracellular rifampicin delivery and pharmacokinetics significantly increased the efficacy of rifampicin-driven killing of intracellular BCG and Mtb bacilli in infected macrophages both in vitro and ex vivo. Such innovative nanocarrier approach may potentially enhance anti-TB drug efficacy and reduce drug side effects.

3.
Clin Cancer Res ; 2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31350312

RESUMO

Purpose Multiple negative regulators restrict the ability of T cells to attack tumors. This work demonstrates the role of PI3K-interacting protein 1 (Pik3ip1) in restraining T cell responses and antitumor immunity. Experimental Design An anti-Pik3ip1 monoclonal antibody (mAb) was generated to identify the Pik3ip1 expression pattern of hematopoietic cells. Pik3ip1-/- mice and a Pik3ip1 fusion protein were generated to investigate the effect of Pik3ip1 on T cell-mediated antitumor immunity in MC38 and B16-F10 tumor models. Immunoblotting and confocal microscopy were used to identify inhibitory effects of Pik3ip1 on T cell receptor (TCR) signaling. Pik3ip1 expression was quantified, and its impact on T cell function in human tumors was measured. Results We demonstrated that Pik3ip1 was predominantly expressed on T cells and served as an essential rheostat for T cell-mediated immunity. A Pik3ip1 genetic deficiency led to enhanced T cell responsiveness upon immunization with a neoantigen. Pik3ip1-/- mice exhibited a marked increase in antitumor immunity and were resistant to tumor growth. Furthermore, Pik3ip1 extracellular domain fusion protein enhanced MC38 tumor growth was observed. Mechanistically, we found that Pik3ip1 inhibited TCR signaling by mediating the degradation of SLP76 through Pik3ip1 oligomerization via its extracellular region. Consistent with the results from the mouse models, PIK3IP1 expression correlated with T cell dysfunction in human tumors. Conclusions Our data reveal a critical role for Pik3ip1 as a novel inhibitory immune regulator of T cell responses and provide a potential molecular target for cancer immunotherapy.

4.
Nat Microbiol ; 4(8): 1378-1388, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31110366

RESUMO

Mycobacterium tuberculosis (Mtb)-derived components are usually recognized by pattern recognition receptors to initiate a cascade of innate immune responses. One striking characteristic of Mtb is their utilization of different type VII secretion systems to secrete numerous proteins across their hydrophobic and highly impermeable cell walls, but whether and how these Mtb-secreted proteins are sensed by host immune system remains largely unknown. Here, we report that MPT53 (Rv2878c), a secreted disulfide-bond-forming-like protein of Mtb, directly interacts with TGF-ß-activated kinase 1 (TAK1) and activates TAK1 in a TLR2- or MyD88-independent manner. MPT53 induces disulfide bond formation at C210 on TAK1 to facilitate its interaction with TRAFs and TAB1, thus activating TAK1 to induce the expression of pro-inflammatory cytokines. Furthermore, MPT53 and its disulfide oxidoreductase activity is required for Mtb to induce the host inflammatory responses via TAK1. Our findings provide an alternative pathway for host signalling proteins to sense Mtb infection and may favour the improvement of current vaccination strategies.

5.
Cancer Immunol Res ; 2018 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-30401678

RESUMO

Elucidation of the mechanisms of T cell-mediated antitumor responses will provide information for the rational design and development of cancer immunotherapies. Here, we found that calnexin, an endoplasmic reticulum (ER) chaperone protein, is significantly upregulated in oral squamous cell carcinoma (OSCC). Upregulation of its membranous expression on OSCC cells is associated with inhibited T-cell infiltration in tumor tissues and correlates with poor survival of OSCC patients. We found that calnexin inhibits the proliferation of CD4+ and CD8+ T cells isolated from the whole blood of healthy donors and OSCC patients and inhibits the secretion of IFNγ, TNFα, and IL2 from these cells. Furthermore, in a melanoma model, knockdown of calnexin enhanced the infiltration and effector functions of T cells in the tumor microenvironment and conferred better control of tumor growth, whereas treatment with a recombinant calnexin protein impaired the infiltration and effector functions of T cells and promoted tumor growth. We also found that calnexin enhanced the expression of PD-1 on CD4+ and CD8+ T cells by restraining the DNA methylation status of a CpG island in the PD-1 promoter. Thus, this work uncovers a mechanism by which T-cell antitumor responses are regulated by calnexin in tumor cells and suggests that calnexin might serve as a potential target for the improvement of antitumor immunotherapy.

6.
Bull Cancer ; 105(5): 493-501, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29576222

RESUMO

BACKGROUND: The immunosuppression of tumor-infiltrating lymphocytes (TILs) is associated with rapid progression of hepatitis B virus-related hepatocellular carcinoma (HBV-HCC). T cell Ig- and mucin-domain-containing molecule-3 (Tim-3) and programmed cell death 1 (PD-1) are important inhibitory molecules expressed on the surface of T cells, but their roles in the function of TILs in HBV-HCC are poorly understood. We aimed to study the roles of these two markers in HBV-HCC. METHODS: Ninety patients with pathologically confirmed HBV-associated HCC were enrolled in our study. Blood samples, paired fresh tumor tissues and adjacent tissues were collected, and isolating peripheral blood mononuclear cells, TILs and adjacent-infiltrating lymphocytes were isolated from these samples. The patients were followed-up to allow survival analysis. RESULTS: Tim-3 or/and PD-1 was up-regulated expressed on CD4+ and CD8+ TILs in HBV-HCC patients and a higher proportion of TILs expressed PD-1 alone. Tim-3+ and PD-1+ TILs greatly decreased secretion of IFN-? and TNF-a. Expression of Tim-3 and PD-1 on TILs negatively correlated with disease-free survival of HCC patients. Direct blockade of Tim-3 and PD-1 in vitro significantly enhanced TILs proliferation and secretion of IFN-? and TNF-a. CONCLUSION: Expression of Tim-3 and/or PD-1 on TILs impairs their function and correlates negatively with disease-free survival in HBV-HCC. Direct blockade of Tim-3 and PD-1 restores anti-tumor effects of TILs, which suggests a potential target for novel immunotherapy in HBV-HCC.


Assuntos
Carcinoma Hepatocelular/imunologia , Receptor Celular 2 do Vírus da Hepatite A/antagonistas & inibidores , Hepatite B/complicações , Neoplasias Hepáticas/imunologia , Linfócitos do Interstício Tumoral/imunologia , Proteínas de Neoplasias/antagonistas & inibidores , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Adulto , Idoso , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/virologia , Feminino , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Vírus da Hepatite B , Humanos , Interferon gama/metabolismo , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/virologia , Linfócitos do Interstício Tumoral/metabolismo , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
8.
Cell Mol Immunol ; 15(3): 206-215, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29151578

RESUMO

The lack of an effective preventative vaccine against tuberculosis (TB) presents a great challenge to TB control. Since it takes an extremely long time to accurately determine the protective efficacy of TB vaccines, there is a great need to identify the surrogate signatures of protection to facilitate vaccine development. Unfortunately, antigen-specific Th1 cytokines that are currently used to evaluate the protective efficacy of the TB vaccine, do not align with the protection and failure of TB vaccine candidates in clinical trials. In this review, we discuss the limitation of current Th1 cytokines as surrogates of protection and address the potential elements that should be considered to finalize the true functional signatures of protective immunity against TB.

9.
Microb Pathog ; 111: 402-409, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28826765

RESUMO

Since 2013, a novel Influenza A (H7N9) virus strain has continued to circulate within poultry and causing human disease. Influenza A (H7N9) virus results in two types of infection: mild and severe. The different results of clinical findings may be related with host susceptibility and characteristics of the virus itself. In order to investigate potential pathogenesis of Influenza A (H7N9) virus, we performed pathogenecity and cytokines analysis of two isolates, A/Guangdong/6/2013 H7N9 virus (GD-6) from a patient with a mild infection, and A/Guangdong/7/2013 H7N9 virus (GD-7) from a patient with a fatal infection. We found that GD-7 replicated to higher levels than GD-6 in human peripheral blood mononuclear cells (PBMCs), lung tissues, and mice. Furthermore, GD-7 infection resulted in more severe lung damage in mice lung tissues than GD-6 infection. GD-7 elicited higher levels of interleukin-6 (IL-6) and tumor necrosis factor-α(TNF-α) than GD-6 did. In conclusion, GD-7 was more pathogenic and induced higher levels of proinflammatory cytokines than GD-6 did.


Assuntos
Subtipo H7N9 do Vírus da Influenza A/patogenicidade , Influenza Humana/virologia , Interleucina-6/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Citocinas/genética , Citocinas/metabolismo , Feminino , Humanos , Subtipo H7N9 do Vírus da Influenza A/genética , Subtipo H7N9 do Vírus da Influenza A/isolamento & purificação , Subtipo H7N9 do Vírus da Influenza A/fisiologia , Influenza Humana/metabolismo , Influenza Humana/mortalidade , Influenza Humana/patologia , Interleucina-6/genética , Pulmão/metabolismo , Pulmão/patologia , Pulmão/virologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Fator de Necrose Tumoral alfa/genética , Virulência , Replicação Viral
10.
Sci Rep ; 6: 32725, 2016 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-27601302

RESUMO

While there is an urgent need to develop new and effective drugs for treatment of tuberculosis (TB) and multi-drug resistant TB (MDR-TB), repurposing FDA (U.S. Food and Drug Administration) -approved drugs for development of anti-TB agents may decrease time and effort from bench to bedside. Here, we employed host cell-based high throughput screening (HTS) assay to screen and characterize FDA-approved, off-patent library drugs for anti-Mycobacterium tuberculosis (MTB) activities. The cell-based HTS allowed us to identify an anti-cancer drug of bis-biguanide dihydrochloride (BBD) as potent anti-mycobacteria agent. Further characterization showed that BBD could inhibit intracellular and extracellular growth of M. smegmatis and slow-growing M. bovis BCG. BBD also potently inhibited replication of clinically-isolated MTB and MDR-TB strains. The proof-of-concept study showed that BBD treatment of MTB-infected mice could significantly decrease CFU counts in the lung and spleen. Notably, comparative evaluation showed that MTB CFU counts in BBD-treated mice were lower than those in rifampicin-treated mice. No apparent BBD side effects were found in BBD-treated mice. Thus, our findings support further studies to develop BBD as a new and effective drug against TB and MDR-TB.


Assuntos
Antituberculosos/administração & dosagem , Biguanidas/administração & dosagem , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Animais , Antituberculosos/farmacologia , Biguanidas/farmacologia , Replicação do DNA/efeitos dos fármacos , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Reposicionamento de Medicamentos , Humanos , Pulmão/efeitos dos fármacos , Pulmão/microbiologia , Camundongos , Mycobacterium bovis/efeitos dos fármacos , Mycobacterium smegmatis/efeitos dos fármacos , Baço/efeitos dos fármacos , Baço/microbiologia , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia
11.
Cell Cycle ; 15(18): 2527-38, 2016 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-27494776

RESUMO

Induction of cell apoptosis is one of the major host defense mechanisms through which macrophages control Mycobacterium tuberculosis (Mtb) infection. However, the mechanisms underlying macrophage apoptosis triggered by Mtb infection are still largely unknown. In this study, a microarray profiling survey revealed 14 miRNAs were down-regulated in CD14+ monocytes from active pulmonary tuberculosis patients, and only the reduction of miR-20a-5p could be reversed after successful anti-tuberculosis treatment. Validation of miR-20a-5p expression was confirmed using real time qPCR. Moreover, miR-20a-5p expression also decreased in differentiated THP-1 macrophages after mycobacterial infection in vitro. Functional assays through forced or inhibited expression of miR-20a-5p in THP-1 macrophages demonstrated that miR-20a-5p functioned as a negative regulator of mycobacterial-triggered apoptosis. Importantly, inhibition of miR-20a-5p expression resulted in more efficient mycobacterial clearance from infected THP-1 macrophages while miR-20a-5p overexpression promoted mycobacterial survival. Mechanistically, miR-20a-5p was demonstrated to regulate Bim expression in a JNK2-dependent manner, unlike Bcl2, and luciferase assay showed JNK2 was a novel direct target of miR-20a-5p. Together, our findings indicate that downregulation of miR-20a-5p triggers macrophage apoptosis as a novel mechanism for host defense against mycobacterial infection.

13.
Sci Rep ; 6: 23351, 2016 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-27025258

RESUMO

Macrophages play a crucial role in host innate anti-mycobacterial defense, which is tightly regulated by multiple factors, including microRNAs. Our previous study showed that a panel of microRNAs was markedly up-regulated in macrophages upon mycobacterial infection. Here, we investigated the biological function of miR-146a during mycobacterial infection. miR-146a expression was induced both in vitro and in vivo after Mycobacterium bovis BCG infection. The inducible miR-146a could suppress the inducible nitric oxide (NO) synthase (iNOS) expression and NO generation, thus promoting mycobacterial survival in macrophages. Inhibition of endogenous miR-146a increased NO production and mycobacterial clearance. Moreover, miR-146a attenuated the activation of nuclear factor κB and mitogen-activated protein kinases signaling pathways during BCG infection, which in turn repressed iNOS expression. Mechanistically, miR-146a directly targeted tumor necrosis factor (TNF) receptor-associated factor 6 (TRAF6) at post-transcriptional level. Silencing TRAF6 decreased iNOS expression and NO production in BCG-infected macrophages, while overexpression of TRAF6 reversed miR-146a-mediated inhibition of NO production and clearance of mycobacteria. Therefore, we demonstrated a novel role of miR-146a in the modulation of host defense against mycobacterial infection by repressing NO production via targeting TRAF6, which may provide a promising therapeutic target for tuberculosis.


Assuntos
Macrófagos/metabolismo , MicroRNAs/genética , Mycobacterium bovis/crescimento & desenvolvimento , Óxido Nítrico/biossíntese , Tuberculose/genética , Animais , Western Blotting , Linhagem Celular , Células Cultivadas , Feminino , Regulação da Expressão Gênica , Interações Hospedeiro-Patógeno/genética , Sistema de Sinalização das MAP Quinases , Macrófagos/microbiologia , Camundongos Endogâmicos C57BL , Viabilidade Microbiana , Microscopia Confocal , Mycobacterium bovis/fisiologia , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator 6 Associado a Receptor de TNF/genética , Fator 6 Associado a Receptor de TNF/metabolismo , Tuberculose/metabolismo , Tuberculose/microbiologia
14.
Sci Rep ; 6: 20481, 2016 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-26857726

RESUMO

The effect of antigen specific immunotherapy (SIT) on asthma is supposed to be improved. Published data indicate that administration of probiotics alleviates allergic diseases. B cells play important roles in the pathogenesis of allergic diseases. This study aims to modulate antigen specific B cell property by the administration of Clostridium butyrate (CB) in combination with SIT. The results showed that after a 3-month treatment, the total asthma clinical score and serum specific IgE were improved in the patients treated with SIT, which was further improved in those treated with both SIT and CB, but not in those treated with CB alone. Treatment with SIT and CB increased p300 and STAT3 activation, up regulated the IL-10 gene transcription and increased the frequency of peripheral antigen specific B cells. In conclusion, administration with SIT in combination with CB converts Der p 1 specific B cells to regulatory B cells in asthma patients allergic to Der p 1. The data suggest a potential therapeutic remedy in the treatment of allergic diseases.


Assuntos
Antígenos de Dermatophagoides/imunologia , Proteínas de Artrópodes/imunologia , Asma , Linfócitos B Reguladores , Clostridium butyricum , Cisteína Endopeptidases/imunologia , Imunoglobulina E , Imunoterapia/métodos , Asma/sangue , Asma/imunologia , Asma/terapia , Linfócitos B Reguladores/imunologia , Linfócitos B Reguladores/metabolismo , Proteína p300 Associada a E1A/sangue , Proteína p300 Associada a E1A/imunologia , Feminino , Humanos , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Interleucina-10/sangue , Interleucina-10/imunologia , Masculino , Fator de Transcrição STAT3/sangue , Fator de Transcrição STAT3/imunologia
15.
Cell Mol Immunol ; 13(5): 700-8, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26166761

RESUMO

Dengue virus (DENV) remains a major public health threat because no vaccine or drugs are available for the prevention and treatment of DENV infection, and the immunopathogenesis mechanisms of DENV infection are not fully understood. Cytotoxic molecules, such as granzyme B (GrzB), may be necessary to control viral infections. However, the exact role of GrzB during DENV infection and the mechanisms regulating GrzB expression during DENV infection are not clear. This study found that miR-27a*, miR-30e, and miR-378 were down-regulated in DENV-infected patients, and DENV infection in humans induced a significant up-regulation of GrzB in natural killer (NK) cells and CD8(+) T cells. Further investigation indicated that NK cells, but not CD8(+) T cells, were the major sources of GrzB, and miR-378, but not miR-27a* or miR-30e, suppressed GrzB expression in NK cells. Notably, we found that overexpression of miR-378 using a miR-378 agomir in DENV-infected mice inhibited GrzB expression and promoted DENV replication. These results suggest the critical importance of miR-378 in the regulation of GrzB expression and a protective role for GrzB in controlling DENV replication in vivo. Therefore, this study provides a new insight into the immunopathogenesis mechanism of DENV infection and a biological basis for the development of new therapeutic strategies to control DENV infection.


Assuntos
Vírus da Dengue/fisiologia , Dengue/imunologia , Dengue/virologia , Granzimas/metabolismo , Células Matadoras Naturais/metabolismo , MicroRNAs/metabolismo , Antagomirs/farmacologia , Sequência de Bases , Dengue/genética , Vírus da Dengue/efeitos dos fármacos , Regulação para Baixo/genética , Humanos , Células Matadoras Naturais/efeitos dos fármacos , MicroRNAs/genética , Perforina/metabolismo , Replicação Viral/efeitos dos fármacos
16.
Proc Natl Acad Sci U S A ; 112(29): E3883-92, 2015 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-26150504

RESUMO

Molecular mechanisms for T-cell immune responses modulated by T cell-inhibitory molecules during tuberculosis (TB) infection remain unclear. Here, we show that active human TB infection up-regulates CD244 and CD244 signaling-associated molecules in CD8(+) T cells and that blockade of CD244 signaling enhances production of IFN-γ and TNF-α. CD244 expression/signaling in TB correlates with high levels of a long noncoding RNA (lncRNA)-BC050410 [named as lncRNA-AS-GSTT1(1-72) or lncRNA-CD244] in the CD244(+)CD8(+) T-cell subpopulation. CD244 signaling drives lncRNA-CD244 expression via sustaining a permissive chromatin state in the lncRNA-CD244 locus. By recruiting polycomb protein enhancer of zeste homolog 2 (EZH2) to infg/tnfa promoters, lncRNA-CD244 mediates H3K27 trimethylation at infg/tnfa loci toward repressive chromatin states and inhibits IFN-γ/TNF-α expression in CD8(+) T cells. Such inhibition can be reversed by knock down of lncRNA-CD244. Interestingly, adoptive transfer of lncRNA-CD244-depressed CD8(+) T cells to Mycobacterium tuberculosis (MTB)-infected mice reduced MTB infection and TB pathology compared with lncRNA-CD244-expressed controls. Thus, this work uncovers previously unidentified mechanisms in which T cell-inhibitory signaling and lncRNAs regulate T-cell responses and host defense against TB infection.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Epigênese Genética , Imunidade , RNA Longo não Codificante/genética , Transdução de Sinais , Tuberculose/imunologia , Transferência Adotiva , Animais , Anticorpos Monoclonais/farmacologia , Antígenos CD , Apoptose/efeitos dos fármacos , Apoptose/genética , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Cromatina/metabolismo , Biologia Computacional , Sequência Conservada , Proteína Potenciadora do Homólogo 2 de Zeste , Epigênese Genética/efeitos dos fármacos , Evolução Molecular , Técnicas de Silenciamento de Genes , Genoma Humano , Células HEK293 , Humanos , Imunidade/efeitos dos fármacos , Imunidade/genética , Interferon gama/biossíntese , Interferon gama/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Camundongos , Modelos Biológicos , Complexo Repressor Polycomb 2/metabolismo , Regiões Promotoras Genéticas/genética , Ligação Proteica/efeitos dos fármacos , Receptores Imunológicos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Proteína Associada à Molécula de Sinalização da Ativação Linfocitária , Família de Moléculas de Sinalização da Ativação Linfocitária , Fatores de Transcrição/metabolismo , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/genética , Regulação para Cima/efeitos dos fármacos
17.
Appl Microbiol Biotechnol ; 99(22): 9685-98, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26219500

RESUMO

Severe dengue is more likely found during secondary heterologous dengue virus (DENV) infection or primary infection of infants born to dengue-immune mothers and led to the hypothesis of antibody-dependent enhancement (ADE). It has been reported that pre-membrane (prM)-reactive antibodies do not efficiently neutralize DENV infection but instead potently promote ADE infection. Meanwhile, these enhancing anti-prM antibodies mainly react with the precursor (pr) peptide. To evaluate the effect of pr gene substitution on neutralization and ADE of DENV infection, a novel chimeric dengue virus (JEVpr/DENV2) was rationally constructed by replacing the DENV pr gene with Japanese encephalitis virus (JEV) pr gene, based on the full-length infectious complementary DNA (cDNA) clone of DENV2 ZS01/01. We found that chimeric JEVpr/DENV2 showed reduced virulence and good immunogenicity. In addition, anti-JEVpr/DENV2 sera showed broad cross-reactivity and efficient neutralizing activity with all four DENV serotypes and immature DENV2 (ImDENV2). Most importantly, compared with anti-DENV2 sera, anti-JEVpr/DENV2 sera showed significantly reduced enhancing activity of DENV infection in K562 cells. These results suggest that the ADE activities could be reduced by replacing the DENV pr gene with JEV pr gene. These findings may help us better understand the pathogenesis of DENV infection and provide a reference for the development of a vaccine against DENV.


Assuntos
Anticorpos Antivirais/imunologia , Anticorpos Facilitadores , Vírus da Dengue/genética , Vírus da Dengue/imunologia , Vírus da Encefalite Japonesa (Subgrupo)/genética , Genética Reversa , Proteínas do Envelope Viral/metabolismo , Linhagem Celular , Humanos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Recombinação Genética , Virulência
18.
Appl Microbiol Biotechnol ; 99(14): 5917-27, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25822571

RESUMO

Dengue vaccine development is considered a global public health priority, but the antibody-dependent enhancement (ADE) issues have critically restricted vaccine development. Recent findings have demonstrated that pre-membrane (prM) protein was involved in dengue virus (DENV) infection enhancement. Although the importance of prM antibodies have been well characterized, only a few epitopes in DENV prM protein have ever been identified. In this study, we screened five potential linear epitopes located at positions pr1 (1-16aa), pr3 (13-28aa), pr4 (19-34aa), pr9 (49-64aa), and pr10 (55-70aa) in pr protein using peptide scanning and comprehensive bioinformatics analysis. Then, we found that only pr4 (19-34aa) could elicit high-titer antibodies in Balb/c mice, and this epitope could react with sera from DENV2-infected patients, suggesting that specific antibodies against epitope peptide pr4 were elicited in both DENV-infected mice and human. In addition, our data demonstrated that anti-pr4 sera showed limited neutralizing activity but significant ADE activity toward standard DENV serotypes and imDENV. Hence, it seems responsible to hypothesize that anti-pr4 serum was infection-enhancing antibody and pr4 was infection-enhancing epitope. In conclusion, we characterized a novel infection-enhancing epitope on dengue pr protein, a finding that may provide new insight into the pathogenesis of DENV infection and contribute to dengue vaccine design.


Assuntos
Anticorpos Antivirais/imunologia , Anticorpos Facilitadores , Vírus da Dengue/imunologia , Vírus da Dengue/patogenicidade , Mapeamento de Epitopos , Epitopos de Linfócito B/imunologia , Proteínas do Envelope Viral/imunologia , Animais , Linhagem Celular , Humanos , Camundongos Endogâmicos BALB C
19.
PLoS Pathog ; 10(10): e1004426, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25329476

RESUMO

Mycobacterium tuberculosis infection is associated with a spectrum of clinical outcomes, from long-term latent infection to different manifestations of progressive disease. Pro-inflammatory pathways, such as those controlled by IL-1ß, have the contrasting potential both to prevent disease by restricting bacterial replication, and to promote disease by inflicting tissue damage. Thus, the ultimate contribution of individual inflammatory pathways to the outcome of M. tuberculosis infection remains ambiguous. In this study, we identified a naturally-occurring polymorphism in the human IL1B promoter region, which alters the association of the C/EBPß and PU.1 transcription factors and controls Mtb-induced IL-1ß production. The high-IL-1ß expressing genotype was associated with the development of active tuberculosis, the severity of pulmonary disease and poor treatment outcome in TB patients. Higher IL-1ß expression did not suppress the activity of IFN-γ-producing T cells, but instead correlated with neutrophil accumulation in the lung. These observations support a specific role for IL-1ß and granulocytic inflammation as a driver of TB disease progression in humans, and suggest novel strategies for the prevention and treatment of tuberculosis.


Assuntos
Alelos , Proteína beta Intensificadora de Ligação a CCAAT/genética , Suscetibilidade a Doenças/microbiologia , Interleucina-1beta/genética , Proteínas Proto-Oncogênicas/genética , Transativadores/genética , Tuberculose/microbiologia , Linhagem Celular , Humanos , Interferon gama/metabolismo , Pulmão/microbiologia
20.
Tuberculosis (Edinb) ; 94(3): 238-44, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24566282

RESUMO

IL-22 has been suggested to play an important role in immune response against Mycobacterium tuberculosis infection. However, the exact role of IL-22 in human tuberculosis (TB) infection remains unclear and the regulatory mechanism of IL-22 response in human TB is unknown. In this study, we observed that successful anti-tuberculosis treatment induced an enhanced and sustained M. tuberculosis antigen-specific IL-22 response, correlated with the decrease of the frequencies of CD19(+)CD5(+)CD1d(+) regulatory B cells. We also found that depletion of CD19(+) B cells significantly enhanced M. tuberculosis antigen-specific IL-22 production by peripheral blood mononuclear cells. More importantly, we observed that purified CD19(+) B cells, and more efficiently, CD19(+)CD5(+)CD1d(+) regulatory B cells, suppressed IL-22 production. In summary, we showed here for the first time that effective anti-tuberculosis treatment restores M. tuberculosis antigen-specific IL-22 response through a novel mechanism by reducing the frequencies of CD19(+)CD5(+)CD1d(+) regulatory B cells in human TB.


Assuntos
Antituberculosos/imunologia , Linfócitos B Reguladores/imunologia , Interleucinas/biossíntese , Tuberculose Pulmonar/tratamento farmacológico , Adulto , Antígenos de Bactérias/imunologia , Antígenos CD/imunologia , Antituberculosos/uso terapêutico , Linfócitos B Reguladores/metabolismo , Linfócitos T CD4-Positivos/imunologia , Estudos de Coortes , Feminino , Humanos , Interferon gama/biossíntese , Interleucina-17/biossíntese , Masculino , Mycobacterium tuberculosis/imunologia , Escarro/microbiologia , Tuberculose Pulmonar/imunologia
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