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1.
Viruses ; 14(5)2022 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-35632774

RESUMO

Sentinox (STX) is an acid-oxidizing solution containing hypochlorous acid in spray whose virucidal activity against SARS-CoV-2 has been demonstrated. In this paper, results of a randomized controlled trial (RCT) on the efficacy of STX in reducing viral load in mild COVID-19 patients (NCT04909996) and a complementary in vitro study on its activity against different respiratory viruses are reported. In the RCT, 57 patients were randomized (1:1:1) to receive STX three (STX-3) or five (STX-5) times/day plus standard therapy or standard therapy only (controls). Compared with controls, the log10 load reduction in groups STX-3 and STX-5 was 1.02 (p = 0.14) and 0.18 (p = 0.80), respectively. These results were likely driven by outliers with extreme baseline viral loads. When considering subjects with baseline cycle threshold values of 20-30, STX-3 showed a significant (p = 0.016) 2.01 log10 reduction. The proportion of subjects that turned negative by the end of treatment (day 5) was significantly higher in the STX-3 group than in controls, suggesting a shorter virus clearance time. STX was safe and well-tolerated. In the in vitro study, ≥99.9% reduction in titers against common respiratory viruses was observed. STX is a safe device with large virucidal spectrum and may reduce viral loads in mild COVID-19 patients.


Assuntos
Tratamento Farmacológico da COVID-19 , Vírus , Humanos , SARS-CoV-2 , Testes Sorológicos , Carga Viral
2.
Int J Mol Sci ; 23(4)2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35216344

RESUMO

Phenylketonuria (PKU) is a rare autosomal recessive inborn error of metabolism where the mainstay of treatment is a Phe restricted diet consisting of a combination of limited amounts of natural protein with supplementation of Phe-free or low-Phe protein substitutes and special low protein foods. Suboptimal outcomes may be related to the different absorption kinetics of free AAs, which have lower biological efficacy than natural proteins. Physiomimic TechnologyTM is a technology engineered to prolong AA (AA-PT) release allowing physiological absorption and masking the odor and taste of free AAs. The aim of these studies was to assess the impact of AA-PT formulation on selected functional and metabolic parameters both in acute and long-term experimental studies. Adult rats in fasting conditions were randomized in different groups and treated by oral gavage. Acute AA-PT administration resulted in significantly lower BUN at 90 min versus baseline. Both BUN and glycemia were modulated in the same direction as intact casein protein. Long-term treatment with AA-PT significantly reduces the protein expression of the muscle degradation marker Bnip3L (-46%) while significantly increasing the proliferation of market myostatin (+58%). Animals dosed for 15 days with AA-PT had significantly stronger grip strength (+30%) versus baseline. In conclusion, the results suggest that the AA-PT formulation may have beneficial effects on both AA oxidation and catabolism with a direct impact on muscle as well as on other metabolic pathways.


Assuntos
Aminoácidos/metabolismo , Aminoácidos/farmacologia , Fenilcetonúrias/tratamento farmacológico , Fenilcetonúrias/metabolismo , Animais , Biomarcadores/metabolismo , Caseínas/metabolismo , Dieta com Restrição de Proteínas/métodos , Masculino , Proteínas de Membrana/metabolismo , Miostatina/metabolismo , Ratos , Ratos Wistar
3.
Eur Arch Otorhinolaryngol ; 278(8): 3099-3103, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33575830

RESUMO

INTRODUCTION: To eliminate the COVID-19 pandemic, the transmission of the virus SARS-CoV-2 among the population needs to be blocked and/or at least reduced. Upper respiratory tract viral loads are highest in the early stages of the disease, and high loads are associated with higher mortality rates. This study aims to evaluate the virucidal efficacy of AOS2020, a novel sprayable Acid-Oxidizing solution containing pure and stable hypochlorous acid (HClO), on human coronavirus SARS-Cov-2 in vitro, and the tolerability profile on nasal and oral mucosa suggesting to be a potential solution for upper respiratory hygiene. METHOD: Virucidal assays and intranasal and oral irritation tests were undertaken in accordance with relevant national and international guidance and methods. RESULTS: In pre-clinical tests, the AOS2020, showed > 99.8% virucidal efficacy in < 1 min against SARS-Cov-2. The safety profile testing on both the nasal and oral mucosa indicates that AOS2020 is non-irritant. CONCLUSION: These initial results indicate that this product has the potential treatment to reduce viral load in the upper respiratory tract.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Higiene , Ácido Hipocloroso/farmacologia , Nariz , Oxirredução , Pandemias
4.
J. inborn errors metab. screen ; 6: e170030, 2018. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1090955

RESUMO

Abstract An innovative technology (Physiomimic Technology) has been applied to amino acids (AAs) formulated for patients with phenylketonuria, with the objective of masking AA taste and odor and prolonging AA release in the gut, allowing a physiological absorption. This technology entails that the AAs are processed with functional additives that are able to modify their release and their organoleptic features. Two prototypes, obtained using sodium alginate + ethylcellulose (engP-1) or sodium alginate + ethylcellulose + glyceryl dibehenate (engP-2), have been tested for AA prolonged release versus the same AAs (n-engP) without the application of the Physiomimic Technology. In vitro tests indicated that the technology is able to prolong the release of the engineered AAs versus the free compounds. A crossover in vivo kinetic study in pigs showed reduced peak concentrations (Cmax) and, as expected, similar areas under the concentration/time curve (up to 5 hours) for the engineered products versus the free AAs. Significantly lower Cmax values (P < .01) were attained for essential AAs, large neutral AAs, and branched-chain AAs, indicating that the technology is able to reduce the typical absorption peak of free AAs. Taste and odor masking has been obtained as a consequence of the AA coating. The Physiomimic Technology, applied to free AAs, provided AA mixes with improved organoleptic features and with modified AA kinetics sustaining a more physiological AA absorption.

5.
Wounds ; 27(10): 265-73, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26479210

RESUMO

OBJECTIVE: Biofilms represent a key challenge in the treatment of chronic wounds, as they are among the main reasons for delays in chronic wound healing. This in vitro study was aimed at evaluating the activity of a new acid-oxidizing solution (AOS) on biofilm formation. Acid-oxidizing solution contains free chlorine species with stabilized hypochlorous acid in high concentration (> 95%) and is characterized by acidic (pH less than 3) and super-oxidizing (Redox greater than 1000mV) features. MATERIALS AND METHODS: A 3-dimensional in vitro model of reconstructed human epidermis was used to compare the activity of AOS vs 2 reference products (RP) containing betaine and polyhexanide (RP1) and sodium hypochlorite and hypochlorous acid (RP2). Different approaches were used to assess the prevention and eradication of methicillin-resistant Staphyloccocus aureus biofilm by the study products. Xylitol and chlorhexidine were used as positive controls. The activity of the study products on the biofilm structure was evaluated analyzing the ultrastructural modification by scanning electron microscopy, while skin compatibility was assessed on noncolonized tissues measuring the metabolic activity of the cells. RESULTS: In all experiments, AOS showed to be active on the biofilm matrix, modifying its structure and allowing bacterial release from the matrix. In all experiments, no cytotoxicity was observed in the tissues treated with the product suggesting a good compatibility of AOS with skin tissues. Reference product 1 affected the biofilm, suggesting a disruption effect; RP2 was slightly less active than AOS in modifying the biofilm structure. CONCLUSION: Treatment with AOS affects biofilm by modifying its structure and therefore facilitating local bacteria accessibility to bactericidal agents, with consequent potential clinical benefits in the treatment of chronic wounds.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Farmacorresistência Bacteriana/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Meticilina/farmacologia , Soluções Farmacêuticas/farmacologia , Hipoclorito de Sódio/farmacologia , Infecção dos Ferimentos/microbiologia , Biofilmes/crescimento & desenvolvimento , Humanos , Técnicas In Vitro , Microscopia Eletrônica de Varredura , Cicatrização/efeitos dos fármacos , Infecção dos Ferimentos/patologia
6.
Int J Pharm ; 393(1-2): 55-60, 2010 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-20363308

RESUMO

The aim of the research was to assess the bioequivalence between Rapidfilm, a new patented delivery system, versus the traditional orodispersible tablet (ODT). A randomized, two-way, single dose, crossover, bioequivalence study was conducted in 24 fasting, healthy volunteers with two formulations of ondansetron (Ondansetron Rapidfilm vs. Zofran Zydis Lingual ODT by GlaxoSmithKline GmbH & Co. KG). Plasma samples were analysed by a validated LC-MS/MS method during a collection period of 24 h post-dosing. The analysis of variance (ANOVA) on the targeted pharmacokinetic parameters did not show any significant difference between the two formulations and 90% confidence intervals (CIs) fell within the common acceptance range of 80-125%, satisfying the bioequivalence criteria. These results allow Rapidfilm to claim the same panel of indications of the conventional immediate release oral solid dosage forms, but offering several advantages also over the ODT: it can result in higher patient convenience for several applications.


Assuntos
Antieméticos/farmacocinética , Ondansetron/farmacocinética , Cooperação do Paciente , Antagonistas da Serotonina/farmacocinética , Administração Oral , Adulto , Análise de Variância , Antieméticos/administração & dosagem , Antieméticos/efeitos adversos , Antieméticos/sangue , Antieméticos/química , Química Farmacêutica , Cromatografia Líquida , Estudos Cross-Over , Formas de Dosagem , Portadores de Fármacos , Composição de Medicamentos , Feminino , Humanos , Masculino , Ondansetron/administração & dosagem , Ondansetron/efeitos adversos , Ondansetron/sangue , Ondansetron/química , Antagonistas da Serotonina/administração & dosagem , Antagonistas da Serotonina/efeitos adversos , Antagonistas da Serotonina/sangue , Antagonistas da Serotonina/química , Espectrometria de Massas em Tandem , Equivalência Terapêutica
7.
Methods Mol Biol ; 380: 285-311, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17876100

RESUMO

The nonobese diabetic (NOD) mouse represents probably the best spontaneous model for a human autoimmune disease. It has provided not only essential information on type 1 diabetes (T1D) pathogenesis, but also valuable insights into mechanisms of immunoregulation and tolerance. Importantly, it allows testing of immunointervention strategies potentially applicable to man. The fact that T1D incidence in the NOD mouse is sensitive to environmental conditions, and responds, sometimes dramatically, to immunomanipulation, does not represent a limit of the model, but is likely to render it even more similar to its human counterpart. In both cases, macrophages, dendritic cells, CD4+, CD8+, and B cells are present in the diseased islets. T1D is a polygenic disease, but, both in human and in NOD mouse T1D, the primary susceptibility gene is located within the MHC. On the other hand, T1D incidence is significantly higher in NOD females, although insulitis is similar in both sexes, whereas in humans, T1D occurs with about equal frequency in males and females. In addition, NOD mice have a more widespread autoimmune disorder, which is not the case in the majority of human T1D cases. Despite these differences, the NOD mouse remains the most representative model of human T1D, with similarities also in the putative target autoantigens, including glutamic acid decarboxylase IA-2, and insulin.


Assuntos
Autoanticorpos/biossíntese , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/metabolismo , Modelos Animais de Doenças , Animais , Tolerância Imunológica/imunologia , Camundongos , Camundongos Endogâmicos NOD
8.
J Immunol ; 179(3): 1559-67, 2007 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-17641022

RESUMO

Chronic nonbacterial prostatitis is a poorly defined syndrome of putative autoimmune origin. To further understand its pathogenesis, we have analyzed autoimmune prostatitis in the NOD mouse, a strain genetically prone to develop different organ-specific autoimmune diseases. Spontaneous development of autoimmune prostatitis in the NOD male, defined by lymphomonuclear cell infiltration in the prostate gland, is well-established by approximately 20 wk of age and is stably maintained afterward. Disease development is indistinguishable in NOD and NOR mice, but is markedly delayed in IFN-gamma-deficient NOD mice. A T cell response to the prostate-specific autoantigen prostatic steroid-binding protein (PSBP) can be detected in NOD males before development of prostate infiltration, indicating lack of tolerance to this self Ag. The intraprostatic inflammatory infiltrate is characterized by Th1-type CD4(+) T cells, which are able to transfer autoimmune prostatitis into NOD.SCID recipients. We characterize here experimental autoimmune prostatitis, detected by intraprostatic infiltrate and PSBP-specific T cell responses, induced in 6- to 8-wk-old NOD males by immunization with synthetic peptides corresponding to the C1 subunit of PSBP. Three PSBP peptides induce in NOD mice vigorous T and B cell responses, paralleled by a marked lymphomononuclear cell infiltration in the prostate. Two of these peptides, PSBP(21-40) and PSBP(61-80), correspond to immunodominant self epitopes naturally processed in NOD mice after immunization with PSBP, whereas peptide PSBP(91-111) represents a cryptic epitope. These model systems address pathogenetic mechanisms in autoimmune prostatitis and will facilitate testing and mechanistic analysis of therapeutic approaches in this condition.


Assuntos
Proteína de Ligação a Androgênios/administração & dosagem , Autoantígenos/administração & dosagem , Doenças Autoimunes/imunologia , Fragmentos de Peptídeos/administração & dosagem , Prostatite/imunologia , Sequência de Aminoácidos , Proteína de Ligação a Androgênios/imunologia , Proteína de Ligação a Androgênios/metabolismo , Animais , Apresentação de Antígeno/imunologia , Autoantígenos/imunologia , Autoantígenos/metabolismo , Doenças Autoimunes/metabolismo , Doenças Autoimunes/patologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/transplante , Movimento Celular/imunologia , Células Cultivadas , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos SCID , Dados de Sequência Molecular , Especificidade de Órgãos/imunologia , Fragmentos de Peptídeos/imunologia , Fragmentos de Peptídeos/metabolismo , Prostateína , Prostatite/metabolismo , Prostatite/patologia , Ratos , Tolerância a Antígenos Próprios/imunologia
9.
J Immunol ; 178(1): 145-53, 2007 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-17182549

RESUMO

1,25-Dihydroxyvitamin D(3) (1,25(OH)(2)D(3)) is an immunomodulatory agent inducing dendritic cells (DCs) to become tolerogenic. To further understand its mechanisms of action, we have examined the effects of 1,25(OH)(2)D(3) on tolerogenic properties of blood myeloid (M-DCs) and plasmacytoid (P-DCs) human DC subsets. Exposure of M-DCs to 1,25(OH)(2)D(3) up-regulated production of CCL22, a chemokine attracting regulatory T cells, whereas production of CCL17, the other CCR4 ligand, was reduced. 1,25(OH)(2)D(3) also decreased IL-12p75 production by M-DCs, as expected, and inhibited CCR7 expression. 1,25(OH)(2)D(3) treatment markedly increased CD4(+) suppressor T cell activity while decreasing the capacity of M-DCs to induce Th1 cell development. Surprisingly, 1,25(OH)(2)D(3) did not exert any discernible effect on tolerogenic properties of P-DCs, and even their high production of IFN-alpha was not modulated. In particular, the intrinsically high capacity of P-DCs to induce CD4(+) suppressor T cells was unaffected by 1,25(OH)(2)D(3). Both DC subsets expressed similar levels of the vitamin D receptor, and its ligation by 1,25(OH)(2)D(3) similarly activated the primary response gene cyp24. Interestingly, 1,25(OH)(2)D(3) inhibited NF-kappaB p65 phosphorylation and nuclear translocation in M-DCs but not P-DCs, suggesting a mechanism for the inability of 1,25(OH)(2)D(3) to modulate tolerogenic properties in P-DCs.


Assuntos
Calcitriol/farmacologia , Calcitriol/fisiologia , Células Dendríticas/efeitos dos fármacos , Tolerância Imunológica/efeitos dos fármacos , Células Mieloides/efeitos dos fármacos , Transporte Ativo do Núcleo Celular , Antígenos CD4/análise , Quimiocina CCL17 , Quimiocina CCL22 , Quimiocinas CC/metabolismo , Células Dendríticas/imunologia , Expressão Gênica/efeitos dos fármacos , Antígenos de Histocompatibilidade Classe II/genética , Humanos , Terapia de Imunossupressão , Ligantes , Glicoproteínas de Membrana , Células Mieloides/imunologia , NF-kappa B/metabolismo , Fosforilação , Plasmócitos/efeitos dos fármacos , Plasmócitos/imunologia , Receptores CCR4 , Receptores de Calcitriol/agonistas , Receptores de Superfície Celular/genética , Receptores de Quimiocinas/metabolismo , Receptores Imunológicos , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Transcrição Gênica/efeitos dos fármacos
10.
Burns ; 32(8): 964-72, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17045406

RESUMO

A multi-centre, open, within-patient controlled study was performed on 23 adult burnt patients to investigate the effectiveness, safety and tolerability of Veloderm in comparison with Algisite M and Jaloskin in split-thickness skin graft donor site care. The areas dressed with Veloderm completely healed within 10-13 days in a significant higher proportion than the other two dressings (47.6% for Veloderm versus 26.3% for Algisite M and 10% for Jaloskin, P<0.03), showing during the whole study less incidence of exudates and of peri-lesional erythema. The aesthetic outcome of the treated lesions after healing was significantly better for Veloderm (P=0.0016). Veloderm) and Jaloskin required very few renewals of the medication during the first week of treatment, while Algisite M needed several multiple re-dressings. Veloderm was judged better than the other two treatments as far as the acceptability (P<0.001), ease of use (P<0.001) and efficacy (P<0.00001). Both pain during application or at removal of dressings and local infections were negligible with all treatments. No scars were formed in any skin donor site. In conclusion Veloderm is a safe and effective dressing for the re-epithelialization of the skin graft donor sites: it showed higher activity than the other two compared dressings.


Assuntos
Queimaduras/cirurgia , Curativos Oclusivos , Polissacarídeos/uso terapêutico , Transplante de Pele/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Cicatriz , Eritema/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Infecção dos Ferimentos/etiologia
11.
J Immunol ; 173(4): 2280-7, 2004 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-15294940

RESUMO

Type 1 diabetes (T1D) is an autoimmune disease characterized by leukocyte infiltration into the pancreatic islets, and we have previously shown that treatment of adult NOD mice with a vitamin D analog arrests the progression of insulitis, blocks Th1 cell infiltration into the pancreas, and markedly reduces T1D development, suggesting inhibition of chemokine production by islet cells. In this study, we show that all TLRs are expressed by mouse and human islet cells, and their engagement by pathogen-derived ligands markedly enhances proinflammatory chemokine production. The vitamin D analog significantly down-regulates in vitro and in vivo proinflammatory chemokine production by islet cells, inhibiting T cell recruitment into the pancreatic islets and T1D development. The inhibition of islet chemokine production in vivo persists after restimulation with TLR ligands and is associated with up-regulation of IkappaBalpha transcription, an inhibitor of NF-kappaB and with arrest of NF-kappaBp65 nuclear translocation, highlighting a novel mechanism of action exerted by vitamin D receptor ligands potentially relevant for the treatment of T1D and other autoimmune diseases.


Assuntos
Quimiocinas/biossíntese , Quimiotaxia de Leucócito/imunologia , Diabetes Mellitus Tipo 1/prevenção & controle , Ilhotas Pancreáticas/imunologia , Linfócitos T/imunologia , Vitamina D/farmacologia , Animais , Células Cultivadas , Quimiocinas/imunologia , Regulação para Baixo , Imunofluorescência , Humanos , Proteínas I-kappa B/efeitos dos fármacos , Proteínas I-kappa B/imunologia , Proteínas I-kappa B/metabolismo , Ilhotas Pancreáticas/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos NOD , Inibidor de NF-kappaB alfa , NF-kappa B/efeitos dos fármacos , NF-kappa B/imunologia , NF-kappa B/metabolismo , Transporte Proteico/efeitos dos fármacos , Transporte Proteico/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Vitamina D/análogos & derivados
12.
J Steroid Biochem Mol Biol ; 89-90(1-5): 437-41, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15225816

RESUMO

Vitamin D receptor (VDR) ligands, in addition to controlling calcium metabolism, exert important effects on the growth and differentiation of many cell types and possess pronounced pro-tolerogenic immunoregulatory activities. VDR ligands can act directly on T cells, but antigen-presenting cells (APCs), and in particular dendritic cells (DCs), appear to be primary targets for their tolerogenic properties. The capacity of VDR ligands to target APCs and T cells is mediated by VDR expression in both cell types and by the presence of common targets in their signal transduction pathways, such as the nuclear factor NF-kB that is down-regulated in APCs and in T cells. VDR ligands can induce in vitro and in vivo tolerogenic DCs able to enhance CD4(+)CD25(+) suppressor T cells that, in turn, inhibit Th1 cell responses. These mechanisms of action can explain some of the immunoregulatory properties of VDR ligands, and are potentially relevant for the treatment of Th1-mediated autoimmune diseases and allograft rejection.


Assuntos
Células Dendríticas/metabolismo , Receptores de Calcitriol/metabolismo , Células Dendríticas/imunologia
13.
Semin Immunol ; 16(2): 127-34, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15036236

RESUMO

Immunosuppressive and anti-inflammatory agents are able to generate tolerogenic DCs, leading, in some cases, to induction or enhancement of regulatory T cells with suppressive activity. This novel mechanism of action, shared by several immunosuppressive and anti-inflammatory agents, is becoming firmly established and contributes to explain their functional properties. The possibility to manipulate DCs in vivo using more or less conventional low molecular weight drugs, enabling them to exert tolerogenic activities, could be exploited to better control a variety of chronic inflammatory conditions, from autoimmune diseases to allograft rejection.


Assuntos
Anti-Inflamatórios/farmacologia , Células Dendríticas/efeitos dos fármacos , Tolerância Imunológica/imunologia , Imunossupressores/farmacologia , Linfócitos T/imunologia , Animais , Doenças Autoimunes/tratamento farmacológico , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/fisiologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/imunologia , Diferenciação Celular/fisiologia , Colecalciferol/análogos & derivados , Colecalciferol/farmacologia , Células Dendríticas/imunologia , Células Dendríticas/fisiologia , Rejeição de Enxerto/tratamento farmacológico , Humanos , Tolerância Imunológica/fisiologia , Glicoproteínas de Membrana , Receptores de Calcitriol/agonistas , Receptores de Calcitriol/imunologia , Receptores de Calcitriol/fisiologia , Receptores de Superfície Celular/imunologia , Receptores de Superfície Celular/metabolismo , Receptores Imunológicos/imunologia , Receptores Imunológicos/metabolismo , Receptores de Interleucina-2/imunologia , Linfócitos T/fisiologia
14.
J Immunol ; 171(8): 4040-7, 2003 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-14530324

RESUMO

In the nonobese diabetic (NOD) mouse, pathogenic and suppressor CD4(+) T cells can be distinguished by the constitutive expression of CD25. In this study, we demonstrate that the progression of autoimmune diabetes in NOD mice reflects modifications in both T cell subsets. CD4(+)CD25(+) suppressor T cells from 8-, but not 16-wk-old NOD mice delayed the onset of diabetes transferred by 16-wk-old CD25-depleted spleen cells. These results were paralleled by the inhibition of alloantigen-induced proliferation of CD4(+)CD25(-) cells, indicating an age-dependent decrease in suppressive activity. In addition, CD4(+)CD25(-) pathogenic T cells became progressively less sensitive to immunoregulation by CD4(+)CD25(+) T cells during diabetes development. CD4(+)CD25(-) T cells showed a higher proliferation and produced more IFN-gamma, but less IL-4 and IL-10, whereas CD4(+)CD25(+) T suppressor cells produced significantly lower levels of IL-10 in 16- compared with 8-wk-old NOD mice. Consistent with these findings, a higher frequency of Th1 cells was observed in the pancreas of 16-wk-old compared with 8-wk-old NOD mice. An increased percentage of CD4(+)CD25(-) T cells expressing CD54 was present in 16-wk-old and in diabetic NOD, but not in BALB/c mice. Costimulation via CD54 increased the proliferation of CD4(+)CD25(-) T cells from 16-, but not 8-wk-old NOD mice, and blocking CD54 prevented their proliferation, consistent with the role of CD54 in diabetes development. Thus, the pathogenesis of autoimmune diabetes in NOD mice is correlated with both an enhanced pathogenicity of CD4(+)CD25(-) T cells and a decreased suppressive activity of CD4(+)CD25(+) T cells.


Assuntos
Comunicação Celular/imunologia , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/prevenção & controle , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Transferência Adotiva , Envelhecimento/imunologia , Animais , Anticorpos Bloqueadores/farmacologia , Anticorpos Monoclonais/farmacologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD4-Positivos/transplante , Separação Celular , Células Cultivadas , Citocinas/biossíntese , Diabetes Mellitus Tipo 1/patologia , Imunidade Inata , Molécula 1 de Adesão Intercelular/biossíntese , Molécula 1 de Adesão Intercelular/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos SCID , Receptores de Interleucina-2/biossíntese , Especificidade da Espécie , Subpopulações de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/patologia , Subpopulações de Linfócitos T/transplante , Linfócitos T Reguladores/metabolismo , Linfócitos T Reguladores/transplante , Regulação para Cima/imunologia
15.
J Immunol ; 170(11): 5491-501, 2003 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-12759426

RESUMO

IL-12 administration to nonobese diabetic (NOD) mice induces IFN-gamma-secreting type 1 T cells and high circulating IFN-gamma levels and accelerates insulin-dependent diabetes mellitus (IDDM). Here we show that IL-12-induced IFN-gamma production is dispensable for diabetes acceleration, because exogenous IL-12 could enhance IDDM development in IFN-gamma-deficient as well as in IFN-gamma-sufficient NOD mice. Both in IFN-gamma(+/-) and IFN-gamma(-/-) NOD mice, IL-12 administration generates a massive and destructive insulitis characterized by T cells, macrophages, and CD11c(+) dendritic cells, and increases the number of pancreatic CD4(+) cells secreting IL-2 and TNF-alpha. Surprisingly, IL-12-induced IFN-gamma hinders pancreatic B cell infiltration and inhibits the capacity of APCs to activate T cells. Although pancreatic CD4(+) T cells from IL-12-treated IFN-gamma(-/-) mice fail to up-regulate the P-selectin ligand, suggesting that their entry into the pancreas may be impaired, T cell expansion is favored in these mice compared with IL-12-treated IFN-gamma(+/-) mice because IL-12 administration in the absence of IFN-gamma leads to enhanced cell proliferation and reduced T cell apoptosis. NO, an effector molecule in beta cell destruction, is produced ex vivo in high quantity by pancreas-infiltrating cells through a mechanism involving IL-12-induced IFN-gamma. Conversely, in IL-12-treated IFN-gamma-deficient mice, other pathways of beta cell death appear to be increased, as indicated by the up-regulated expression of Fas ligand on Th1 cells in the absence of IFN-gamma. These data demonstrate that IFN-gamma has a dual role, pathogenic and protective, in IDDM development, and its deletion allows IL-12 to establish alternative pathways leading to diabetes acceleration.


Assuntos
Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Interferon gama/biossíntese , Interferon gama/deficiência , Interleucina-12/administração & dosagem , Animais , Células Apresentadoras de Antígenos/imunologia , Apoptose/genética , Apoptose/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Movimento Celular/genética , Movimento Celular/imunologia , Citocinas/metabolismo , Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 1/prevenção & controle , Regulação para Baixo/genética , Regulação para Baixo/imunologia , Proteína Ligante Fas , Feminino , Inibidores do Crescimento/biossíntese , Inibidores do Crescimento/deficiência , Inibidores do Crescimento/genética , Inibidores do Crescimento/fisiologia , Inflamação/genética , Inflamação/imunologia , Injeções Intraperitoneais , Interferon gama/genética , Interferon gama/fisiologia , Ilhotas Pancreáticas/imunologia , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/patologia , Ligantes , Ativação Linfocitária/imunologia , Contagem de Linfócitos , Subpopulações de Linfócitos/imunologia , Subpopulações de Linfócitos/patologia , Tecido Linfoide/imunologia , Tecido Linfoide/patologia , Masculino , Glicoproteínas de Membrana/biossíntese , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Endogâmicos NOD , Camundongos Knockout , Células Mieloides/imunologia , Células Mieloides/patologia , Óxido Nítrico/biossíntese , Selectina-P/metabolismo , Pâncreas/imunologia , Pâncreas/patologia , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo
16.
J Cell Biochem ; 88(2): 227-33, 2003 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-12520519

RESUMO

Dendritic cells (DCs) not only induce but also modulate T cell activation. 1,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)] induces DCs with a tolerogenic phenotype, characterized by decreased expression of CD40, CD80, and CD86 costimulatory molecules, low IL-12 and enhanced IL-10 secretion. We have found that a short treatment with 1,25(OH)(2)D(3) induces tolerance to fully mismatched mouse islet allografts that is stable to challenge with donor-type spleen cells and allows acceptance of donor-type vascularized heart grafts. This effect is enhanced by co-administration of mycophenolate mofetil (MMF), a selective inhibitor of T and B cell proliferation that has also effects similar to 1,25(OH)(2)D(3) on DCs. Graft acceptance is associated with an increased percentage of CD4(+)CD25(+) regulatory cells in the spleen and in the draining lymph node that can protect 100% of syngeneic recipients from islet allograft rejection. CD4(+)CD25(+) cells, able to inhibit the T cell response to a pancreatic autoantigen and to significantly delay disease transfer by pathogenic CD4(+)CD25(-) cells, are also induced by treatment of adult nonobese diabetic (NOD) mice with 1,25-dihydroxy-16,23Z-diene-26,27-hexafluoro-19-nor vitamin D(3) (BXL-698). This treatment arrests progression of insulitis and Th1 cell infiltration, and inhibits diabetes development at non-hypercalcemic doses. The enhancement of CD4(+)CD25(+) regulatory T cells, able to mediate transplantation tolerance and to arrest type 1 diabetes development by a short oral treatment with VDR ligands, suggests possible clinical applications of this approach.


Assuntos
Células Dendríticas/imunologia , Diabetes Mellitus Tipo 1/imunologia , Tolerância Imunológica/imunologia , Linfócitos T/imunologia , Vitamina D/análogos & derivados , Vitamina D/metabolismo , Animais , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/prevenção & controle , Rejeição de Enxerto/imunologia , Humanos , Ligantes , Camundongos , Camundongos Endogâmicos NOD , Receptores de Calcitriol/imunologia , Receptores de Calcitriol/metabolismo , Transplante Homólogo/imunologia , Vitamina D/imunologia , Vitamina D/uso terapêutico
17.
Diabetes ; 51(5): 1367-74, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11978632

RESUMO

Type 1 diabetes is a chronic progressive autoimmune disease characterized by mononuclear cell infiltration, dominated by interleukin-12 (IL-12)-dependent Th1 cells, of the pancreatic islets, with subsequent destruction of insulin-producing beta-cells. Here, we demonstrate that treatment of adult nonobese diabetic (NOD) mice with an analog of 1alpha,25-dihydroxyvitamin D(3), an immunomodulatory agent preventing dendritic cell maturation, decreases lipopolysaccharide-induced IL-12 and gamma-interferon production, arrests Th1 cell infiltration and progression of insulitis, and inhibits diabetes development at nonhypercalcemic doses. Arrest of disease progression is accompanied by an enhanced frequency in the pancreatic lymph nodes of CD4(+)CD25(+) regulatory T-cells that are able to inhibit the T-cell response to the pancreatic autoantigen insulinoma-associated protein 2 and to significantly delay disease transfer by pathogenic CD4(+)CD25(-) cells. Thus, a short treatment of adult NOD mice with an analog of 1,25-dihydroxyvitamin D(3) inhibits IL-12 production, blocks pancreatic infiltration of Th1 cells, enhances CD4(+)CD25(+) regulatory cells, and arrests the progression of type 1 diabetes, suggesting its possible application in the treatment of human autoimmune diabetes.


Assuntos
Colecalciferol/farmacologia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/imunologia , Células Th1/efeitos dos fármacos , Animais , Antígenos CD4/análise , Colecalciferol/análogos & derivados , Feminino , Citometria de Fluxo , Interferon gama/biossíntese , Interleucina-12/biossíntese , Ilhotas Pancreáticas/imunologia , Lipopolissacarídeos/farmacologia , Linfonodos/citologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Receptores de Interleucina-2/análise , Células Th1/química , Células Th1/metabolismo
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