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1.
Artigo em Inglês | MEDLINE | ID: mdl-33881985

RESUMO

A Gram-stain-negative, aerobic, non-motile and rod-shaped bacterium, designated as IMCC34836T, was isolated from a freshwater stream. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain IMCC34836T was most closely related to Permianibacter aggregans HW001T (of the family Pseudomonadaceae) with 95.6 % sequence similarity and formed a robust clade with P. aggregans HW001T. The draft genome sequence of strain IMCC34836T was 4.4 Mbp in size with 59.1 mol% DNA G+C content. Average nucleotide identity and digital DNA-DNA hybridization values between strain IMCC34836T and P. aggregans HW001T were 71.2 and 22.0 %, respectively, indicating that the new strain represents a novel species. The strain contained iso-C15 : 0, summed feature 3 (C16 : 1 ω6c and/or C16 : 1 ω7c) and summed feature 9 (iso-C17 : 1 ω9c and/or C16 : 1 10-methyl) as the major fatty acids and harboured phosphatidylethanolamine, two unidentified aminophospholipids and three unidentified lipids as major polar lipids. The isoprenoid quinone detected in the strain was ubiquinone-8. Based on the phylogenetic and phenotypic characteristics, strain IMCC34836T is considered to represent a novel species of the genus Permianibacter, for which the name Permianibacter fluminis sp. nov. is proposed. The type strain is IMCC34836T (=KACC 21755T=NBRC 114416T).


Assuntos
Filogenia , Pseudomonadaceae/classificação , Rios/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfatidiletanolaminas , Fosfolipídeos/química , Pseudomonadaceae/isolamento & purificação , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Ubiquinona/química
2.
Indian J Med Res ; 139(1): 117-24, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24604047

RESUMO

BACKGROUND & OBJECTIVES: To study effects of drugs against rheumatoid arthritis (RA) synoviocytes or fibroblast like synoviocytes (FLS) are used. To overcome the drawbacks of using FLS, this study was conducted to show the validity of SW982 synovial cell line in RA study. METHODS: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, Annexin V propidium iodide (PI) staining, mitochondrial membrane potential assay, Triton X-114 Phase partitioning, and immunolot for apoptosis signaling in SW982 human synovial cell line were performed. RESULTS: Fluvastatin induced apoptosis in a dose- and time-dependent manner in TNFα -stimulated SW982 human synovial cells. A geranylgeranylpyrophosphate (GGPP) inhibitor, but not a farnesylpyrophosphate (FPP) inhibitor, induced apoptosis, and fluvastatin-induced apoptosis was associated with the translocation of isoprenylated RhoA and Rac1 proteins from the cell membrane to the cytosol. Fluvastatin-induced downstream apoptotic signals were associated with inhibition of the phosphoinositide 3-kinase (PI3K)/Akt pathway. Accordingly, 89 kDa apoptotic cleavage fragment of poly (ADP-ribose) polymerase (PARP) was detected. INTERPRETATION & CONCLUSIONS: Collectively, our data indicate that fluvastatin induces apoptotic cell death in TNFα-stimulated SW982 human synovial cells through the inactivation of the geranylgerenylated membrane fraction of RhoA and Rac1 proteins and the subsequent inhibition of the PI3K/Akt signaling pathway. This finding shows the validity of SW982 cell line for RA study.


Assuntos
Apoptose/efeitos dos fármacos , Artrite Reumatoide/tratamento farmacológico , Ácidos Graxos Monoinsaturados/administração & dosagem , Indóis/administração & dosagem , Fosfatos de Poli-Isoprenil/antagonistas & inibidores , Artrite Reumatoide/patologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fluvastatina , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Líquido Sinovial/citologia , Líquido Sinovial/efeitos dos fármacos , Sais de Tetrazólio/administração & dosagem , Tiazóis/administração & dosagem
3.
Cancer Cell ; 41(7): 1222-1241.e7, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37433281

RESUMO

For inoperable esophageal adenocarcinoma (EAC), identifying patients likely to benefit from recently approved immunochemotherapy (ICI+CTX) treatments remains a key challenge. We address this using a uniquely designed window-of-opportunity trial (LUD2015-005), in which 35 inoperable EAC patients received first-line immune checkpoint inhibitors for four weeks (ICI-4W), followed by ICI+CTX. Comprehensive biomarker profiling, including generation of a 65,000-cell single-cell RNA-sequencing atlas of esophageal cancer, as well as multi-timepoint transcriptomic profiling of EAC during ICI-4W, reveals a novel T cell inflammation signature (INCITE) whose upregulation correlates with ICI-induced tumor shrinkage. Deconvolution of pre-treatment gastro-esophageal cancer transcriptomes using our single-cell atlas identifies high tumor monocyte content (TMC) as an unexpected ICI+CTX-specific predictor of greater overall survival (OS) in LUD2015-005 patients and of ICI response in prevalent gastric cancer subtypes from independent cohorts. Tumor mutational burden is an additional independent and additive predictor of LUD2015-005 OS. TMC can improve patient selection for emerging ICI+CTX therapies in gastro-esophageal cancer.


Assuntos
Adenocarcinoma , Neoplasias Esofágicas , Neoplasias Gástricas , Humanos , Monócitos , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/genética , Imunoterapia
4.
Pediatrics ; 146(2)2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32611807

RESUMO

BACKGROUND AND OBJECTIVES: Vancomycin remains one of the most commonly prescribed antibiotics in NICUs despite recommendations to limit its use for known resistant infections. Baseline data revealing substantially higher vancomycin use in our NICU compared to peer institutions informed our quality improvement initiative. Our aim was to reduce the vancomycin prescribing rate in neonates hospitalized in our NICU by 50% within 1 year and sustain for 1 year. METHODS: In the 60-bed level IV NICU of an academic referral center, we used a quality improvement framework to develop key drivers and interventions including (1) physician education with benchmarking antibiotic prescribing rates; (2) pharmacy-initiated 48-hour antibiotic time-outs on rounds; (3) development of clinical pathways to standardize empirical antibiotic choices for early-onset sepsis, late-onset sepsis, and necrotizing enterocolitis; coupled with (4) daily prospective audit with feedback from the antimicrobial stewardship program. RESULTS: We used statistical process u-charts to show vancomycin use declined from 112 to 38 days of therapy per 1000 patient-days. After education, pharmacy-initiated 48-hour time-outs, and development of clinical pathways, vancomycin use declined by 29%, and by an additional 52% after implementation of prospective audit with feedback. Vancomycin-associated acute kidney injury also declined from 1.4 to 0.1 events per 1000 patient-days. CONCLUSIONS: Through a sequential implementation approach of education, standardization of care with clinical pathways, pharmacist-initiated 48-hour time-outs, and prospective audit with feedback, vancomycin days of therapy declined by 66% over a 1-year period and has been sustained for 1 year.


Assuntos
Gestão de Antimicrobianos/estatística & dados numéricos , Prescrição Inadequada/prevenção & controle , Unidades de Terapia Intensiva Neonatal/estatística & dados numéricos , Vancomicina/uso terapêutico , Antibacterianos/uso terapêutico , Gestão de Antimicrobianos/organização & administração , Brasil , Procedimentos Clínicos , Enterocolite Necrosante/tratamento farmacológico , Hospitais Pediátricos/estatística & dados numéricos , Hospitais Urbanos/estatística & dados numéricos , Humanos , Prescrição Inadequada/estatística & dados numéricos , Recém-Nascido , Doenças do Recém-Nascido/tratamento farmacológico , Serviço de Farmácia Hospitalar/organização & administração , Estudos Prospectivos , Melhoria de Qualidade , Sepse/tratamento farmacológico
5.
Biochem Biophys Res Commun ; 389(1): 28-33, 2009 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-19698700

RESUMO

Recognition of oligodeoxynucleotides containing CpG motifs (CpG-ODNs) by toll-like receptor 9 (TLR9) inhibits RANKL-induced osteoclastogenesis from precursors. This inhibitory effect suggests the possibility of using this strategy to block pathological bone loss. However, the enhancing effect of CpG-ODNs on OC formation from RANKL-primed pre-osteoclasts (pOCs) has hampered their clinical use. In this report, we developed a CpG-KSK13 oligonucleotide with an alternative CpG motif, and tested its effect on osteoclastogenesis in comparison with previously used murine CpG motif (CpG-1826) or human CpG motif (CpG-2006) oligonucleotides. Murine CpG-1826 inhibited RANKL-induced OC formation from BMMs but not from RANKL-primed pOCs, while CpG-KSK13 treatment strongly inhibited OC formation from both BMM and primed pOC cells. CpG-KSK13 also showed a potent inhibitory effect on human OC differentiation using peripheral blood mononuclear cells (PBMCs), which was in contrast to the species-specific response of murine CpG-1826 or human CpG-2006. Moreover, CpG-KSK13 effectively inhibited NFATc1 activity, but not NF-kappaB or AP-1 activity, and decreased TREM-2 promoter activity and subsequent surface expression of the TREM-2 protein induced by M-CSF and RANKL. These results demonstrate that the recognition of CpG-KSK13 via TLR9 inhibits osteoclastogenesis by down-regulating TREM-2 expression. Thus, our findings provide evidence for the potential use of CpG-KSK13 as an anti-osteoclastogenic agent for human and for pre-clinical animals.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Ilhas de CpG , Glicoproteínas de Membrana/metabolismo , Oligodesoxirribonucleotídeos/farmacologia , Osteoclastos/efeitos dos fármacos , Receptores Imunológicos/metabolismo , Animais , Regulação para Baixo , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Fatores de Transcrição NFATC/antagonistas & inibidores , Osteoclastos/metabolismo , Ligante RANK/metabolismo , Receptor Toll-Like 9/agonistas
6.
Int Immunopharmacol ; 8(10): 1401-7, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18687302

RESUMO

While CpG oligodeoxynucleotides (ODN) are excellent candidates for cancer immunotherapeutics, the numbers of usable CpG ODNs are limited in current clinical settings. To resolve this, we investigated whether novel CpG ODN (KSK-CpG) would be an effective immunotherapeutic in a murine tumor model by affecting in vivo and in vitro parameters, such as survival span, the number of tumor nodules, natural killer (NK) cell and cytotoxic T lymphocyte (CTL) activity and interleukin (IL)-6 or IL-12 cytokine release in splenocytes. We found that KSK-CpG was effective in the murine cancer model by way of prolonging survival span, reducing the number of tumor nodules, augmenting NK cell and CTL cytotoxicity, as well as evoking IL-6 and IL-12 cytokine release in splenocytes. Collectively, these data demonstrate that KSK-CpG is active against the highly malignant B16BL6 and EL4 tumor mouse model via innate immune augmentation.


Assuntos
Células Matadoras Naturais/efeitos dos fármacos , Melanoma Experimental/prevenção & controle , Oligodesoxirribonucleotídeos/uso terapêutico , Linfócitos T Citotóxicos/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Imunoterapia , Interferon gama/imunologia , Interleucina-12/imunologia , Células Matadoras Naturais/imunologia , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Transplante de Neoplasias , Neoplasias , Linfócitos T Citotóxicos/imunologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Int J Biochem Cell Biol ; 38(4): 638-47, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16360334

RESUMO

Trichomonas vaginalis, a flagellated protozoan parasite, is the causative organism of trichomoniasis. We have recently demonstrated that T. vaginalis induces apoptotic cell death via a Bcl-x(L)-dependent pathway in RAW264.7 macrophages. In this study, we attempted to characterize in detail the signaling cascades resulting in T. vaginalis-induced macrophage apoptosis, focusing particularly on mitochondrial changes and the role of p38 mitogen-activated protein kinase (p38 MAPK) activation. We found that T. vaginalis induced mitochondrial changes including the release of cytochrome c and the serial activation of caspases, leading to the activation of p38 MAPK in macrophages. These biochemical changes culminated in the apoptosis of the host cells. Caspase inhibitors induced a significant inhibition of T. vaginalis-induced nuclear damage, as well as the activation of p38 MAPK. Treatment with the p38 MAPK inhibitor, SB203580, or the overexpression of kinase-inactive p38 MAPK, induced an attenuation of T. vaginalis-induced apoptosis but not cytochrome c release, the activation of caspase-9 and caspase-3, or PARP cleavage. Furthermore, SB203580 treatment to human macrophages consistently blocked T. vaginalis-induced apoptosis. Collectively, our findings indicate that p38 MAPK signaling cascade is requisite to apoptosis of T. vaginalis-infected macrophage, and this apoptotic process occurs via the phosphorylation of p38 MAPK, which is located downstream of mitochondria-dependent caspase activation, conferring insight into the plausible molecular mechanism of T. vaginalis-immune evasion from macrophage attack.


Assuntos
Apoptose , Macrófagos/enzimologia , Mitocôndrias/enzimologia , Tricomoníase/enzimologia , Trichomonas vaginalis/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Caspase 3 , Caspase 9 , Caspases/metabolismo , Linhagem Celular , Citocromos c/metabolismo , Humanos , Macrófagos/parasitologia , Camundongos , Mitocôndrias/parasitologia
8.
Mol Cells ; 18(2): 177-85, 2004 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-15528993

RESUMO

Activation of NF-kappaB leads to the production of proinflammatory cytokines such as IL-12 and TNF-alpha that are involved in innate and adaptive immunity. We determined whether T. vaginalis-induced inflammatory response in macrophages associated with NF-kappaB. T. vaginalis adhesion led to transient NF-kappaB activation at 6 h but activation declined dramatically by 8 h. Super-shift assays showed that the gel-shifted complexes consisted of p65 (Rel A) and p50 (NF-kappaB1). NF-kappaB activation was accompanied by IkappaB-alpha degradation, and was inhibited by blocking T. vaginalis adhesion, indicating that the early NF-kappaB activation by T. vaginalis depends on IkappaB-alpha degradation. Quantitative real-time RT-PCR analyses revealed that the expression of TNF-alpha and IL-12 mRNA in T. vaginalis-adhesive cells was rapidly suppressed in comparison with LPS stimulation. We also observed that the parasite inhibited the nuclear translocation of NF-kappaB at 8 h, and diminished IL-12 and TNF-alpha production in response to LPS. In addition, inhibition of IkappaB-alpha degradation by MG-132 resulted in apoptosis. These results demonstrate that effects of T. vaginalis on NF-kappaB regulation are critical for cytokine production and the survival of macrophages. We suggest that there exist inhibitory mechanisms induced by T. vaginalis to evade host immunity.


Assuntos
Citocinas/antagonistas & inibidores , Macrófagos/parasitologia , NF-kappa B/antagonistas & inibidores , Trichomonas vaginalis/imunologia , Animais , Sobrevivência Celular , Citocinas/biossíntese , Ativação Enzimática , Proteínas I-kappa B/metabolismo , Imunidade , Inflamação/parasitologia , Interleucina-12/genética , Cinética , Camundongos , Inibidor de NF-kappaB alfa , NF-kappa B/metabolismo , Subunidade p50 de NF-kappa B , RNA Mensageiro/análise , Fator de Transcrição RelA , Fatores de Transcrição/antagonistas & inibidores , Tricomoníase/imunologia , Fator de Necrose Tumoral alfa/genética
9.
Yonsei Med J ; 45(4): 751-4, 2004 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-15344222

RESUMO

A primitive protozoan parasite Trichomonas vaginalis selectively activates the signal transduction pathways in macrophages (RAW264.7). This study evaluated the correlation of these signaling pathways and T. vaginalis-induced cell apoptosis. In macrophages infected with T. vaginalis, apoptosis was assessed on the basis of DNA fragmentation on agarose gel electrophoresis. Infection of macrophages with T. vaginalis induced tyrosine phosphorylation of several proteins. Infected cells with T. vaginalis were shown to associate with phosphorylation of the extracellular signal-regulated (ERK)1/2 kinase, p38, c-Jun N-terminal kinase (JNK) mitogen-activated protein (MAP) kinases on Western blot analysis. The present finding also demonstrated a link between the ERK1/2, JNK and p38 apoptotic pathways that was modulated by T. vaginalis infection.


Assuntos
Apoptose/imunologia , Macrófagos/citologia , Macrófagos/parasitologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Tricomoníase/imunologia , Trichomonas vaginalis/imunologia , Animais , Humanos , Sistema de Sinalização das MAP Quinases/imunologia , Macrófagos/enzimologia , Fosforilação
10.
Arthritis Res Ther ; 14(1): R14, 2012 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-22264405

RESUMO

INTRODUCTION: Interleukin-34 (IL-34) is a recently defined cytokine, showing a functional overlap with macrophage colony stimulating factor (M-CSF). This study was undertaken to address the expression of IL-34 in rheumatoid arthritis (RA) patients and to investigate its regulation and pathogenic role in RA. METHODS: IL-34 levels were determined in the RA synovium, synovial fluid (SF) and fibroblast-like synovial cells (FLS) by immunohistochemistry, real-time PCR, enzyme-linked immunosorbent assay and immunoblotting. RA activity was assessed using Disease Activity Score 28 (DAS28) activity in the plasma collected at baseline and one year after treatment. Conditioned media (CM) were prepared from RA FLS culture with tumor necrosis factor alpha (TNFα) for 24 hours and used for functional assay. RESULTS: IL-34 was expressed in the synovium, SF, and FLS from RA patients. The production of IL-34 in FLS was up-regulated by TNFα in RA samples compared with osteoarthritis (OA) patients. Importantly, the preferential induction of IL-34 rather than M-CSF by TNFα in RAFLS was mediated by the transcription factor nuclear factor kappa B (NF-κB) and activation of c-Jun N-terminal kinase (JNK). IL-34 elevation in plasma from RA patients was decreased after the administration of disease-modifying anti-rheumatic drugs (DMARDs) in accordance with a decrease in DAS28. CM from RAFLS cultured with TNFα promoted chemotactic migration of human peripheral blood mononuclear cells (PBMCs) and subsequent osteoclast (OC) formation, effects that were attenuated by an anti-IL-34 antibody. CONCLUSIONS: These data provide novel information about the production of IL-34 in RA FLS and indicate that IL-34 is an additional osteoclastogenic factor regulated by TNFα in RA, suggesting a discrete role of IL-34 in inflammatory RA diseases.


Assuntos
Artrite Reumatoide/metabolismo , Fibroblastos/metabolismo , Membrana Sinovial/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Adulto , Idoso , Artrite Reumatoide/genética , Artrite Reumatoide/patologia , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Meios de Cultivo Condicionados/farmacologia , Ativação Enzimática/efeitos dos fármacos , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Humanos , Immunoblotting , Imuno-Histoquímica , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , NF-kappa B/metabolismo , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Líquido Sinovial/metabolismo , Membrana Sinovial/efeitos dos fármacos , Membrana Sinovial/patologia , Fator de Necrose Tumoral alfa/farmacologia , Regulação para Cima/efeitos dos fármacos , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/farmacologia
11.
Cell Biol Int ; 32(10): 1207-14, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18675368

RESUMO

The present study was to see whether echinomycin-induced apoptosis would be NF-kappaB-dependent and if so, whether echinomycin would activate or inhibit NF-kappaB as well as resultant chemokine IL-8 expression. In HT-29 cells echinomycin activated NF-kappaB in time-dependent manner. EMSA in the presence of antibodies specific for p50 and p65 subunits indicated that echinomycin-induces the translocation of p50-p65 heterodimeric subunits of NF-kappaB. Levels of IkappaB were detected at initial echinomycin treatment and thereafter decreased, faintly seen after a 6h treatment. In contrast p-IkappaB levels were clearly detected throughout 6-24h of echinomycin treatment, albeit initially fainted. To clarify the role of NF-kappaB on IL-8 expression in echinomycin-mediated apoptosis of HT-29 cells, ELISA plus RT-PCR clearly showed that IL-8 production is inducible by echinomycin treatment. Using a specific inhibitor, IL-8 regulation at echinomycin treatment in HT-29 cells occurred via both caspase-3 and NF-kappaB-dependent signal pathway. To confirm whether two different pathways (NF-kappaB and caspase) would be coupled, only NF-kappaB inhibitor (PDTC) and caspase-3 specific inhibitor (Z-DEVD-FMK) together significantly attenuated echinomycin-initiated apoptosis of HT-29 cells, pretreatment of HT-29 cells with PDTC rarely affected echinomycin-induced caspase-3 activation. So echinomycin-induced apoptosis in HT-29 cells occurs via NF-kappaB activation independent of caspase-3 activation modulating the resultant-linked key chemokine IL-8 expression and echinomycin-induced apoptosis is NF-kappaB-dependant and directly related to NF-kappaB activation, consequently regulating IL-8 expression.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias do Colo/metabolismo , Equinomicina/farmacologia , Interleucina-8/metabolismo , NF-kappa B/metabolismo , Caspase 3/metabolismo , Inibidores de Caspase , Linhagem Celular Tumoral , Inibidores de Cisteína Proteinase/metabolismo , Ativação Enzimática , Humanos , Quinase I-kappa B/genética , Quinase I-kappa B/metabolismo , Interleucina-8/genética , Leupeptinas/metabolismo , NF-kappa B/genética , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
12.
Immunology ; 118(2): 164-70, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16771851

RESUMO

Toll-like receptors (TLRs) are pattern recognition receptors (PRRs) that recognize conserved pathogen-associated molecular patterns (PAMPs) synthesized by micro-organisms. Despite the essential requirement for TLRs in prokaryotic infection, the pattern and regulation of TLR gene expression by Trichomonas vaginalis in the mucocutaneous barrier are still unknown. Our hypothesis is that T. vaginalis-infected epithelial cells are major effector cells in the skin barrier. These cells function as a central regulator of TLR gene expression, thus accelerating the process of barrier dysfunction via increased release of chemokines and proinflammatory cytokines. To test this hypothesis, RT-PCR was performed on TLRs, interleukin (IL)-8 and tumour necrosis factor (TNF)-alpha. Stimulation of HeLa cells by T. vaginalis was observed to up-regulate TLR2, 4 and 9 mRNA expression as well as that of IL-8 and TNF-alpha. To further clarify the molecular mechanism of barrier devastation triggered by these up-regulatory stimuli, we examined the profiles of extracellular signal-regulated kinase (ERK), p38 mitogen-activated protein kinase (MAPK) and nuclear factor (NF)-kappaB activation in HeLa cells using specific inhibitors. Interestingly, pretreatment of HeLa cells with the p38 MAPK inhibitor SB203580 demonstrated inhibition of T. vaginalis-induced up-regulation of TLR2, 4, and 9 mRNA expression. By contrast, inhibition of ERK or NF-kappaB activation failed to block T. vaginalis-induced up-regulation of TLR9 mRNA expression or TLR2 and TLR4 mRNA expression, respectively. In addition, pretreatment with SB203580 reduced epithelium-derived IL-8 and TNF-alpha release evoked by T. vaginalis. Our results show that T. vaginalis infection of the mucocutaneous barrier could up-regulate TLR2, 4 and 9 gene expression via the p38 MAPK signalling pathway in epithelial cells; this process then leads to modulation of p38 MAPK-dependent IL-8 and TNF-alpha release from the epithelium.


Assuntos
Receptores Toll-Like/biossíntese , Tricomoníase/imunologia , Trichomonas vaginalis , Proteínas Quinases p38 Ativadas por Mitógeno/imunologia , Animais , MAP Quinases Reguladas por Sinal Extracelular/imunologia , Células HeLa , Humanos , Interleucina-8/biossíntese , Interleucina-8/genética , NF-kappa B/imunologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Transdução de Sinais/imunologia , Receptor 2 Toll-Like/biossíntese , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/biossíntese , Receptor 4 Toll-Like/genética , Receptor Toll-Like 9/biossíntese , Receptor Toll-Like 9/genética , Receptores Toll-Like/genética , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/genética , Regulação para Cima/imunologia
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