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1.
Int J Mol Sci ; 25(3)2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38338859

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative disorder and the predominant form of dementia globally. No reliable diagnostic, predictive techniques, or curative interventions are available. MicroRNAs (miRNAs) are vital to controlling gene expression, making them valuable biomarkers for diagnosis and prognosis. This study examines the transcriptome of olfactory ecto-mesenchymal stem cells (MSCs) derived from individuals with the PSEN1(A431E) mutation (Jalisco mutation). The aim is to determine whether this mutation affects the transcriptome and expression profile of miRNAs and their target genes at different stages of asymptomatic, presymptomatic, and symptomatic conditions. Expression microarrays compare the MSCs from mutation carriers with those from healthy donors. The results indicate a distinct variation in the expression of miRNAs and mRNAs among different symptomatologic groups and between individuals with the mutation. Using bioinformatics tools allows us to identify target genes for miRNAs, which in turn affect various biological processes and pathways. These include the cell cycle, senescence, transcription, and pathways involved in regulating the pluripotency of stem cells. These processes are closely linked to inter- and intracellular communication, vital for cellular functioning. These findings can enhance our comprehension and monitoring of the disease's physiological processes, identify new disorder indicators, and develop innovative treatments and diagnostic tools for preventing or treating AD.


Assuntos
Doença de Alzheimer , Células-Tronco Mesenquimais , MicroRNAs , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Doença de Alzheimer/metabolismo , Mutação , Biomarcadores/metabolismo , Células-Tronco Mesenquimais/metabolismo
2.
Int Immunol ; 36(3): 111-128, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38066638

RESUMO

Nurr1 is a member of the orphan nuclear receptor family NR4A (nuclear receptor subfamily 4 group A) that modulates inflammation in several cell lineages, both positively and negatively. Macrophages are key regulators of inflammatory responses, yet information about the role of Nurr1 in human macrophages is scarce. Here we examined Nurr1 expression and activity in steady state and activated human macrophages. Pro- and anti-inflammatory macrophages were generated in vitro by culture of blood monocytes with granulocyte/macrophage colony-stimulating factor (GM-CSF) and macrophage colony-stimulating factor (M-CSF), respectively. Nurr1 expression was predominant in macrophages with the pro-inflammatory phenotype. Nurr1 activation with the agonists 1,1-bis(3'-indolyl)-1-(p-chlorophenyl) methane (C-DIM12) or isoxazolo-pyridinone 7e (IP7e) did not globally modify the polarization status of pro-inflammatory macrophages, but they decreased their production of TNF, IL-1ß, IL-6, IL-8, IL-12 p40, CCL2, IFN-ß, and reactive oxygen species, with variable potencies. Conversely, Nurr1 deficient macrophages increased the expression of transcripts encoding inflammatory mediators, particularly that of IL6, IFNB1, and CCL2. Mechanistically, endogenous Nurr1 interacted with NF-κB p65 in basal conditions and upon lipopolysaccharide (LPS)-mediated activation. C-DIM12 stabilized those complexes in cells exposed to LPS and concurrently decreased NF-κB transcriptional activity and p65 nuclear translocation. Expression of high levels of Nurr1 was associated with a subset of dermal macrophages that display enhanced levels of TNF and lower expression of the anti-inflammatory marker CD163L1 in skin lesions from patients with bullous pemphigoid (BP), a chronic inflammatory autoimmune blistering disorder. These results suggest that Nurr1 expression is linked with the pro-inflammatory phenotype of human macrophages, both in vivo and in vitro, where it may constitute a brake to attenuate the synthesis of inflammatory mediators.


Assuntos
Fator Estimulador de Colônias de Macrófagos , NF-kappa B , Humanos , NF-kappa B/metabolismo , Fator Estimulador de Colônias de Macrófagos/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Inflamação/metabolismo , Mediadores da Inflamação/metabolismo , Anti-Inflamatórios/metabolismo
3.
Int J Mol Sci ; 24(16)2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37628788

RESUMO

Alzheimer's disease (AD), the most common neurodegenerative disease and the first cause of dementia worldwide, has no effective treatment, and its pathological mechanisms are not yet fully understood. We conducted this study to explore the proteomic differences associated with Familial Alzheimer's Disease (FAD) in olfactory ecto-mesenchymal stem cells (MSCs) derived from PSEN1 (A431E) mutation carriers compared with healthy donors paired by age and gender through two label-free liquid chromatography-mass spectrometry approaches. The first analysis compared carrier 1 (patient with symptoms, P1) and its control (healthy donor, C1), and the second compared carrier 2 (patient with pre-symptoms, P2) with its respective control cells (C2) to evaluate whether the protein alterations presented in the symptomatic carrier were also present in the pre-symptom stages. Finally, we analyzed the differentially expressed proteins (DEPs) for biological and functional enrichment. These proteins showed impaired expression in a stage-dependent manner and are involved in energy metabolism, vesicle transport, actin cytoskeleton, cell proliferation, and proteostasis pathways, in line with previous AD reports. Our study is the first to conduct a proteomic analysis of MSCs from the Jalisco FAD patients in two stages of the disease (symptomatic and presymptomatic), showing these cells as a new and excellent in vitro model for future AD studies.


Assuntos
Doença de Alzheimer , Células-Tronco Mesenquimais , Doenças Neurodegenerativas , Humanos , Doença de Alzheimer/genética , Proteoma , Proteômica
4.
PLoS One ; 18(4): e0283726, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37023111

RESUMO

Arylamine N-acetyltransferase 2 has been related to drug side effects and cancer susceptibility; its protein structure and acetylation capacity results from the polymorphism's arrays on the NAT2 gene. Absorption, distribution, metabolism, and excretion, cornerstones of the pharmacological effects, have shown diversity patterns across populations, ethnic groups, and even interethnic variation. Although the 1000 Genomes Project database has portrayed the global diversity of the NAT2 polymorphisms, several populations and ethnicities remain underrepresented, limiting the comprehensive picture of its variation. The NAT2 clinical entails require a detailed landscape of its striking diversity. This systematic review spans the genetic and acetylation patterns from 164 articles from October 1992 to October 2020. Descriptive studies and controls from observational studies expanded the NAT2 diversity landscape. Our study included 243 different populations and 101 ethnic minorities, and, for the first time, we presented the global patterns in the Middle Eastern populations. Europeans, including its derived populations, and East Asians have been the most studied genetic backgrounds. Contrary to the popular perception, Africans, Latinos and Native Americans have been significantly represented in recent years. NAT2*4, *5B, and *6A were the most frequent haplotypes globally. Nonetheless, the distribution of *5B and *7B were less and more frequent in Asians, respectively. Regarding the acetylator status, East Asians and Native Americans harboured the highest frequencies of the fast phenotype, followed by South Europeans. Central Asia, the Middle East, and West European populations were the major carriers of the slow acetylator status. The detailed panorama presented herein, expands the knowledge about the diversity patterns to genetic and acetylation levels. These data could help clarify the controversial findings between acetylator states and the susceptibility to diseases and reinforce the utility of NAT2 in precision medicine.


Assuntos
Arilamina N-Acetiltransferase , Arilamina N-Acetiltransferase/genética , Arilamina N-Acetiltransferase/metabolismo , Acetilação , Polimorfismo Genético , Haplótipos , Fenótipo , Genótipo
5.
Immunobiology ; 227(6): 152299, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36370518

RESUMO

The orphan nuclear receptor Nur77 is involved in diverse cellular processes such as inflammation, proliferation, differentiation and survival. Stimuli like lipopolysaccharide (LPS) and tumor necrosis factor (TNF) increase Nur77 expression in human and murine macrophages, and it has been proposed that Nur77 plays a major role in dampening the inflammatory response. Here, we evaluated the expression and function of Nur77 in human anti-inflammatory and pro-inflammatory macrophages derived from blood monocytes cultured with macrophage colony-stimulating factor (M-MDMs) or granulocyte/macrophage colony-stimulating factor (GM-MDMs), respectively. Nur77 mRNA expression was significantly enhanced in M-MDMs compared with GM-MDMs, both constitutively and upon exposure to Toll-like receptor (TLR)2, 3, and 4 ligands. Nur77 activation with the agonist Cytosporone B (CsnB) significantly suppressed the production of TNF, interleukin (IL)-1ß, IL-6, and IL-8 in GM-MDMs stimulated with LPS. In contrast, it tended to enhance the production of the anti-inflammatory cytokine IL-10. This effect was associated with reduced NF-κB p65 nuclear translocation. Similarly, Nur77 knockdown enhanced TNF production in GM-MDMs. CsnB effectively stimulated the transactivation activity of Nur77 in M-MDMs, but it did not alter cytokine synthesis or p65 nuclear translocation. However, Nur77 seemed to have a role in maintaining the anti-inflammatory profile of M-MDMs, since Nur77-deficient M-MDMs constitutively produced higher levels of TNF transcripts. Thus, in the absence of exogenous agonists, Nur77 activity favors the anti-inflammatory function of M-MDMs, whereas agonistic activation of this receptor preferentially drives attenuation of inflammation in inflammatory macrophages.


Assuntos
Macrófagos , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares , Fenilacetatos , Humanos , Citocinas/metabolismo , Inflamação/metabolismo , Lipopolissacarídeos , Fator Estimulador de Colônias de Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/agonistas , Fenilacetatos/farmacologia
6.
Polymers (Basel) ; 14(4)2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35215700

RESUMO

Nanocomposite engineering of biosensors, biomaterials, and flexible electronics demand a highly tunable synthesis of precursor materials to achieve enhanced or desired properties. However, this process remains limited due to the need for proper synthesis-property strategies. Herein, we report on the ability to synthesize chitosan-gold nanocomposite thin films (CS/AuNP) with tunable properties by chemically reducing HAuCl4 in chitosan solutions and different HAuCl4/sodium citrate molar relationships. The structure, electrical, and relaxation properties of nanocomposites have been investigated as a function of HAuCl4/sodium citrate molar relation. It was shown that gold particle size, conductivity, Vogel temperature (glass transition), and water content strongly depend upon HAuCl4/sodium citrate relationships. Two relaxation processes have been observed in nanocomposites; the α-relaxation process, related to a glass transition in wet CS/AuNP films, and the σ-relaxation related to the local diffusion process of ions in a disordered system. The ability to fine-tune both α- and σ-relaxations may be exploited in the proper design of functional materials for biosensors, biomaterials, and flexible electronics applications.

7.
Immunol Cell Biol ; 98(10): 868-882, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32696992

RESUMO

Obesity is a chronic inflammatory disease associated with adipose tissue macrophage (ATM) activation. ATMs from lean mice contribute to tissue homeostasis by their M2-oriented polarization, whereas obesity leads to an increase of M1 inflammatory ATMs that underlies obesity-related metabolic disorders. In humans, studies characterizing ATMs and their functional status are limited. Here we investigated ATM phenotype in visceral (VAT) and subcutaneous (SAT) adipose tissue from healthy lean and obese individuals using two molecules previously identified as markers of M1-like and M2-like/tissue-resident macrophages, the C-type lectin CLEC5A and the scavenger receptor CD163L1, respectively. CD163L1 was expressed by the majority of ATMs, and CD163L1+ ATM density was greater with respect to cells expressing the pan-macrophage markers CD68 or CD11b. ATM counts in SAT, but not in VAT, increased in obese compared to lean individuals, measured with the three markers. Accordingly, CD163L1, CD68 and ITGAM gene expression was significantly enhanced in obese with respect to control individuals only in SAT. CLEC5A+ ATMs had a proinflammatory profile and were abundant in the lean VAT, but their density diminished in obesity. The only ATM subset that increased its counts in the obese VAT had a mixed M1-like (CD11c+ CD163- CD209- ) and M2-like (CLEC5A- CD206+ ) phenotype. ATM expansion was dominated by a subset of M2-like macrophages (CD11c- CLEC5A- CD163+ CD206+ CD209+ ) in the obese SAT, with a minor contribution of a CD11c+ CLEC5A- ATM subpopulation. Thus, both SAT and VAT seems to limit inflammation during obesity by differentially altering their ATM subset composition.


Assuntos
Gordura Intra-Abdominal/citologia , Macrófagos/citologia , Obesidade , Gordura Subcutânea/citologia , Humanos , Inflamação , Lectinas Tipo C , Ativação de Macrófagos , Glicoproteínas de Membrana , Obesidade/imunologia , Receptores de Superfície Celular , Receptores Depuradores
8.
Oncol Lett ; 15(5): 6777-6783, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29616136

RESUMO

Curcumin is a phytochemical with potent anti-neoplastic properties. The antitumoral effects of curcumin in cells derived from chronic or acute myeloid leukemia have been already described. However, a comparative study of the cytostatic and cytotoxic effects of curcumin on chronic and acute myeloid leukemia cells has not yet been performed. In the present study, the cellular effects of curcumin on cell lines derived from chronic or acute myeloid leukemia were examined. Dose and time-response assays were performed with curcumin on HL-60 and K562 cells. Cell viability was evaluated with trypan blue exclusion test and cell death by flow cytometry using a fluorescent molecular probe. A cell cycle profile was analyzed, and protein markers of cell cycle progression and cell death were investigated. In the present study, the K562 cells showed a higher sensitivity to the cytostatic and cytotoxic effects of curcumin compared with HL-60. In addition, curcumin induced G1 phase arrest in HL-60 cells and G2/M phase arrest in K562 cells. Furthermore, curcumin-related cell death in HL-60 was associated with the processed forms of caspases-9 and -3 proteins, whereas in K562 cells, both the processed and the unprocessed forms were present. Accordingly, activity of these caspases was significantly higher in HL-60 cells compared with that in K562. In conclusion, curcumin elicits different cellular mechanisms in chronic or acute myeloid leukemia cells and the powerful antitumoral effect was more potent in K562 compared with HL-60 cells.

10.
Front Neurosci ; 9: 33, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25717290

RESUMO

We previously demonstrated that, in the early stages of tau processing in Alzheimer's disease, the N-terminal part of the molecule undergoes a characteristic cascade of phosphorylation and progressive misfolding of the proteins resulting in a structural conformation detected by Alz-50. In this immunohistochemical study of AD brain tissue, we have found that C-terminal truncation of tau at Asp-421 was an early event in tau aggregation and analyzed the relationship between phospho-dependent tau epitopes located at the C-terminus with truncation at Glu-391. The aim of this study was to determine whether C-terminal truncation may trigger events leading to the assembly of insoluble PHFs from soluble tau aggregates present in pre-tangle cells. Our findings suggest that there is a complex interaction between phosphorylated and truncated tau species. A model is presented here in which truncated tau protein represents an early neurotoxic species while phosphorylated tau species may provide a neuroprotective role in Alzheimer's disease.

11.
Artigo em Inglês | MEDLINE | ID: mdl-23964211

RESUMO

Alzheimer Disease (AD) is a neurodegenerative disorder and the most common form of dementia. Histopathologically is characterized by the presence of two major hallmarks, the intracellular neurofibrillary tangles (NFTs) and extracellular neuritic plaques (NPs) surrounded by activated astrocytes and microglia. NFTs consist of paired helical filaments of truncated tau protein that is abnormally hyperphosphorylated. The main component in the NP is the amyloid-ß peptide (Aß), a small fragment of 40-42 amino acids with a molecular weight of 4 kD. It has been proposed that the amyloid aggregates and microglia activation are able to favor the neurodegenerative process observed in AD patients. However, the role of inflammation in AD is controversial, because in early stages the inflammation could have a beneficial role in the pathology, since it has been thought that the microglia and astrocytes activated could be involved in Aß clearance. Nevertheless the chronic activation of the microglia has been related with an increase of Aß and possibly with tau phosphorylation. Studies in AD brains have shown an upregulation of complement molecules, pro-inflammatory cytokines, acute phase reactants and other inflammatory mediators that could contribute with the neurodegenerative process. Clinical trials and animal models with non-steroidal anti-inflammatory drugs (NSAIDs) indicate that these drugs may decrease the risk of developing AD and apparently reduce Aß deposition. Finally, further studies are needed to determine whether treatment with anti-inflammatory strategies, may decrease the neurodegenerative process that affects these patients.

12.
J Leukoc Biol ; 90(6): 1119-31, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21937707

RESUMO

Two major subsets of human Mo are identified based on CD14 and CD16 expression: the classical CD16(-) Mo and the minor CD14(+)CD16(+) Mo. In vitro studies suggested distinct function and differentiation potential for each cell population. However, the in vivo relevance of these findings remains unclear. To evaluate the development and function of human Mo in an in vivo model, we transferred both Mo subpopulations into the peritoneum of immunocompromised mice in homeostatic or inflammatory conditions. Inflammation was induced with soluble LPS or particulate zymosan. CD16(+) were more phagocytic and produced higher amounts of TNF and IL-6 than CD16(-) Mo early after transfer with zymosan. They also produced higher levels of ß2-defensin in any condition evaluated, which could represent a new marker for this subpopulation. In contrast, differentiating CD16(-) Mo (24 h after transfer) acquired greater APC capacity in LPS-induced peritonitis, whereas none of the Mo subsets attained this ability with zymosan. CX(3)CL1 supported the survival of both Mo subsets in vivo. Similar Mo subpopulations were present in human peritonitis. These results support the idea of specialized roles of the Mo subset, where CD16(+) might act in an immediate innate immune response, whereas CD16(-) could have a major role as APCs.


Assuntos
Mediadores da Inflamação/fisiologia , Monócitos/imunologia , Monócitos/patologia , Receptores de IgG/biossíntese , Transferência Adotiva , Animais , Proteínas Ligadas por GPI/biossíntese , Proteínas Ligadas por GPI/metabolismo , Humanos , Imunidade Inata , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/patologia , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos SCID , Monócitos/transplante , Peritonite/imunologia , Peritonite/metabolismo , Peritonite/patologia , Receptores de IgG/metabolismo , Zimosan/farmacologia
13.
J Immunol ; 184(4): 1765-75, 2010 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-20083662

RESUMO

Dendritic cells (DCs) are professional APCs involved in the initiation of both immunity and immunological tolerance. In autoimmune diseases or graft rejections, most reactive lymphocytes are effector/memory cells. It is believed that memory T cells are more resistant to tolerance induction than naive lymphocytes; however, studies on mechanisms for their efficient tolerization are still scarce. In this study, we generated human monocyte-derived DCs by culture with GM-CSF and IL-4 (control DCs), as well as tolerogenic DCs (tDCs) by adding IL-10, IL-10/TGF-beta1, or IL-10/IL-6. Cells were maturated with TNF-alpha/PGE(2). Compared with control DCs, tDCs had similar expression of HLA-DR, CD80, and CD86, lower expression of CD40, higher levels of macrophage markers, enhanced endocytic ability, increased secretion of IL-6, IL-10 (only tDCs generated with IL-10 and tDCs generated with IL-10/IL-6), and PGE(2), and lower secretion of IL-12 and IL-23. In vitro, tDCs had the capacity to induce anergy in tetanus toxoid-specific memory CD4(+) T cells, whereas the proliferative response to an unrelated Ag was intact. Anergy could be reverted upon exposure to IL-2. tDC-primed T cells have low suppressive ability. Nevertheless, the generation of both anergic and regulatory T cells was more efficient with tDCs generated with IL-10/TGF-beta1. Microarray-based gene expression profiling reflected modulated expression of several transcripts in tDCs. Surface CLIP-HLA-DR complexes and intracellular thrombospondin-1 were increased in the three tDCs. CD39 was highly expressed only in tDC-TGF, which correlated with increased adenosine production. We propose that these molecules, together with IL-10 and prostanoids, are key factors to induce Ag-specific tolerance in memory T cells.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Diferenciação Celular/imunologia , Citocinas/fisiologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Epitopos de Linfócito T/imunologia , Tolerância Imunológica , Memória Imunológica , Antígenos de Diferenciação de Linfócitos B/fisiologia , Linfócitos T CD4-Positivos/metabolismo , Células Cultivadas , Anergia Clonal/imunologia , Células Dendríticas/classificação , Dinoprostona/fisiologia , Antígenos de Histocompatibilidade Classe II/fisiologia , Humanos , Imunossupressores/farmacologia , Interleucina-10/fisiologia , Macrófagos/classificação , Macrófagos/imunologia , Macrófagos/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Trombospondina 1/fisiologia
14.
J Neurochem ; 112(6): 1353-67, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19943854

RESUMO

We are analyzing the physiological function of Tau protein and its abnormal pathological behavior when this protein is self-assemble into pathological filaments. These aggregates of Tau protein are the main components in many diseases such as Alzheimer's disease (AD). Recent studies suggest that Tau acquires complex oligomeric conformations which may be toxic. In this review, we emphasized the possible phenomena implicated in the formation of these oligomers. Studies with chemical inductors indicates that the microtubule-binding domain is the most important region involved in Tau aggregation and showed the requirement of a pre-arrange Tau in abnormal conformation to promote self-assembly. Transgenic animal models and AD neuropathology studies showed that post-translational modifications are also implicated in Tau aggregation and neural cell death during AD development. Therefore, we analyzed some events that could be present during Tau aggregation. Finally, we included a brief discussion of the possible relation between glucose metabolism dysfunction in AD, and data of Tau aggregation by using aggregation inhibitors. In conclusion, the process Tau aggregation deserves further investigations to design possible therapeutic targets to inhibit the toxicity of these aggregates and it is possible that could be extended to other diseases with similar etiology.


Assuntos
Doença de Alzheimer/metabolismo , Emaranhados Neurofibrilares/metabolismo , Proteínas tau/fisiologia , Doença de Alzheimer/etiologia , Animais , Humanos , Emaranhados Neurofibrilares/patologia , Conformação Proteica , Processamento de Proteína Pós-Traducional , Proteínas tau/toxicidade
15.
Toxicol In Vitro ; 19(8): 1045-50, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15963680

RESUMO

Several nitroimidazole derivatives were synthesized and tested as possible trichomonicidal agents. A fast, simple, practical and reliable in vitro colorimetric method was applied to the screening of the nitroimidazole derivatives anti-trichomonas activity. The colorimetric technique was based on the use of Alamar blue as a redox-indicator. The test was carried out both qualitatively (minimal inhibitory concentration determined by naked eye observation) and quantitatively (fluorometric determination of 50% and 90% inhibitory concentrations), the latter took advantage of the dye fluorometric properties. The performance of the method was excellent affording an exactitude 97.86% and a reproducibility of 95% and no interference of the trichomonas-culture medium was observed during the test. Some of the nitroimidazole compounds tested showed a fair trichomonicidal activity, however none of them was as active as the model compound, metronidazole.


Assuntos
Antitricômonas/toxicidade , Nitroimidazóis/toxicidade , Oxazinas , Trichomonas vaginalis/efeitos dos fármacos , Xantenos , Animais , Bioensaio , Colorimetria , Fluorometria , Indicadores e Reagentes , Oxirredução
16.
Int Immunol ; 16(9): 1251-63, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15277404

RESUMO

We previously demonstrated that tumor necrosis factor (TNF)-alpha-matured CD16- and CD16+ human monocyte-derived dendritic cells (16-mDC and 16+mDC) differentially stimulate naive CD4+ lymphocytes by inducing Th1- and Th2-like responses, respectively. Here, we further characterized the role of different DC maturation factors on Th polarization. Immature 16+mDC and 16-mDC (iDC) obtained by culture of purified monocytes with GM-CSF and IL-4 were maturated with (i) Toll-like receptor (TLR) ligands [lipopolysaccharide (LPS)], (ii) lymphocyte-derived (soluble CD40 ligand, IFN-gamma) and (iii) endogenous inflammatory stimuli [TNF-alpha, prostaglandin (PG)E2]. After activation with these stimuli, DC secrete IL-12 only in presence of LPS, and 16+mDC produced lower amounts of IL-12 and IL-10 than 16-mDC. Allogeneic CD4+CD45RO- lymphocytes co-cultured with 16+mDC secreted higher levels of IL-4 and IL-10 than those co-cultured with 16-mDC, regardless of the maturation stimuli. Results were similar when DC were activated with TLR-2 or TLR-3 ligands. The higher induction of IL-4 by 16+mDC was primarily dependent on IL-12, IL-4 and IL-10. IFN-gamma production by CD4+ T cells was similar with all the conditions except with LPS-16+mDC, which induced reduced amounts of this cytokine. Those differences were totally eliminated by neutralization of IL-12, IL-4 or IL-10. Finally, 16-mDC could reverse the Th2 phenotype of already committed lymphocytes toward a Th1 pattern in short-term cultures, whereas 16+mDC had less ability to skew this phenotype. These results indicate that 16+mDC elicit superior Th2 responses independently of the maturation factors that they received, and suggest that they could represent an important population of regulatory DC.


Assuntos
Citocinas/fisiologia , Células Dendríticas/fisiologia , Monócitos/citologia , Receptores de IgG/análise , Células Th2/imunologia , Humanos , Imunofenotipagem , Interferon gama/biossíntese , Interleucina-10/biossíntese , Interleucina-12/biossíntese , Interleucina-4/biossíntese , Ativação Linfocitária
17.
J Clin Immunol ; 24(1): 86-96, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14997038

RESUMO

Monocyte-derived dendritic cells (mDC) are increasingly used as cancer vaccines. However, human monocytes are a heterogeneous cell population. We showed previously that DC derived from a monocyte subset expressing CD16 (16+mDC) stimulated allogeneic naïve T lymphocytes to secrete higher levels of IL-4 than DC derived from regular CD14(high)CD16(-) monocytes (16-mDC). Th1-type responses have been associated with effective antitumor responses, thus the use of mDC containing 16+mDC as cancer vaccines might be disadvantageous. Here, we evaluate the primary and memory immune response elicited in vitro by 16+mDC and 16-mDC in five patients with metastatic renal cell carcinoma vaccinated with autologous mDC pulsed with tumor lysates (TuLy) and keyhole limpet hemocyanin (KLH). After therapy, three of the five patients had stable disease. Surprisingly, patients with longer survival showed the highest amount of peripheral blood CD16+ monocytes. Analysis of KLH-specific antibodies revealed high titers of IgG2 in patients with longer survival. CD4+ T lymphocyte proliferation against KLH and TuLy increased after treatment, and some patients showed an augmented rate of CD4+ T lymphocyte proliferation against KLH (3/5) and TuLy (2/3) when 16+mDC were used as antigen presenting cells (APC). Before treatment, the IFN-gamma/IL-4 ratio against TuLy and KLH was higher when using 16-mDC as APC, but after vaccination four of five patients had an increased ratio for TuLy with 16+mDC. These results suggest that the immune response elicited by 16-mDC and 16+mDC is modified when memory or naïve T cells are stimulated, and 16+mDC could favor a stronger and more beneficial antitumoral Th1 memory response in vivo.


Assuntos
Vacinas Anticâncer/imunologia , Carcinoma de Células Renais/imunologia , Carcinoma de Células Renais/patologia , Células Dendríticas/imunologia , Imunoterapia , Neoplasias Renais/imunologia , Neoplasias Renais/patologia , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/secundário , Receptores de IgG/imunologia , Adolescente , Adulto , Antígenos de Neoplasias/imunologia , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Vacinas Anticâncer/uso terapêutico , Carcinoma de Células Renais/terapia , Divisão Celular/imunologia , Citocinas/imunologia , Citocinas/metabolismo , Células Dendríticas/patologia , Células Dendríticas/transplante , Hemocianinas/imunologia , Humanos , Hipersensibilidade Tardia/imunologia , Imunoglobulina G/imunologia , Isotipos de Imunoglobulinas/imunologia , Neoplasias Renais/terapia , Neoplasias Pulmonares/terapia , Masculino , Pessoa de Meia-Idade , Nefrectomia
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