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2.
Ann R Coll Surg Engl ; 101(8): e164-e168, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31537109

RESUMO

Neuro-Behçet's disease (NBD) is a serious manifestation of Behçet's disease (BD) and can affect either the central or peripheral nervous systems, or both. It occurs in 10-50% of patients with BD. We report on a patient with an unusual intraparenchymal lesion, initially thought to be a brain tumour. Histological examination revealed vasculitis consistent with BD. Clinicians should include NBD as a differential diagnosis when considering an isolated inflammatory intracranial lesion.


Assuntos
Síndrome de Behçet/diagnóstico , Granuloma de Células Plasmáticas/diagnóstico , Adulto , Síndrome de Behçet/complicações , Síndrome de Behçet/patologia , Biópsia , Encéfalo/patologia , Neoplasias Encefálicas/diagnóstico , Diagnóstico Diferencial , Granuloma de Células Plasmáticas/etiologia , Granuloma de Células Plasmáticas/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino
3.
Clin Exp Immunol ; 183(2): 206-20, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26422112

RESUMO

In 40% of cases of classical Hodgkin lymphoma (cHL), Epstein-Barr virus (EBV) latency-II antigens [EBV nuclear antigen 1 (EBNA1)/latent membrane protein (LMP)1/LMP2A] are present (EBV(+) cHL) in the malignant cells and antigen presentation is intact. Previous studies have shown consistently that HLA-A*02 is protective in EBV(+) cHL, yet its role in disease pathogenesis is unknown. To explore the basis for this observation, gene expression was assessed in 33 cHL nodes. Interestingly, CD8 and LMP2A expression were correlated strongly and, for a given LMP2A level, CD8 was elevated markedly in HLA-A*02(-) versus HLA-A*02(+) EBV(+) cHL patients, suggesting that LMP2A-specific CD8(+) T cell anti-tumoral immunity may be relatively ineffective in HLA-A*02(-) EBV(+) cHL. To ascertain the impact of HLA class I on EBV latency antigen-specific immunodominance, we used a stepwise functional T cell approach. In newly diagnosed EBV(+) cHL, the magnitude of ex-vivo LMP1/2A-specific CD8(+) T cell responses was elevated in HLA-A*02(+) patients. Furthermore, in a controlled in-vitro assay, LMP2A-specific CD8(+) T cells from healthy HLA-A*02 heterozygotes expanded to a greater extent with HLA-A*02-restricted compared to non-HLA-A*02-restricted cell lines. In an extensive analysis of HLA class I-restricted immunity, immunodominant EBNA3A/3B/3C-specific CD8(+) T cell responses were stimulated by numerous HLA class I molecules, whereas the subdominant LMP1/2A-specific responses were confined largely to HLA-A*02. Our results demonstrate that HLA-A*02 mediates a modest, but none the less stronger, EBV-specific CD8(+) T cell response than non-HLA-A*02 alleles, an effect confined to EBV latency-II antigens. Thus, the protective effect of HLA-A*02 against EBV(+) cHL is not a surrogate association, but reflects the impact of HLA class I on EBV latency-II antigen-specific CD8(+) T cell hierarchies.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Antígeno HLA-A2/imunologia , Herpesvirus Humano 4/imunologia , Herpesvirus Humano 4/isolamento & purificação , Doença de Hodgkin/imunologia , Doença de Hodgkin/virologia , Proteínas da Matriz Viral/imunologia , Adolescente , Adulto , Idoso , Apresentação de Antígeno , Linfócitos T CD8-Positivos/virologia , Feminino , Genes MHC Classe I , Antígeno HLA-A2/genética , Herpesvirus Humano 4/genética , Doença de Hodgkin/genética , Doença de Hodgkin/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas da Matriz Viral/genética , Adulto Jovem
4.
Clin Exp Immunol ; 180(2): 255-70, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25496365

RESUMO

Antigen-specific T cell receptor (TCR) gene transfer via patient-derived T cells is an attractive approach to cancer therapy, with the potential to circumvent immune regulatory networks. However, high-affinity tumour-specific TCR clonotypes are typically deleted from the available repertoire during thymic selection because the vast majority of targeted epitopes are derived from autologous proteins. This process places intrinsic constraints on the efficacy of T cell-based cancer vaccines and therapeutic strategies that employ naturally generated tumour-specific TCRs. In this study, we used altered peptide ligands and lentivirus-mediated transduction of affinity-enhanced TCRs selected by phage display to study the functional properties of CD8(+) T cells specific for three different tumour-associated peptide antigens across a range of binding parameters. The key findings were: (i) TCR affinity controls T cell antigen sensitivity and polyfunctionality; (ii) supraphysiological affinity thresholds exist, above which T cell function cannot be improved; and (iii) T cells transduced with very high-affinity TCRs exhibit cross-reactivity with self-derived peptides presented by the restricting human leucocyte antigen. Optimal system-defined affinity windows above the range established for natural tumour-specific TCRs therefore allow the enhancement of T cell effector function without off-target effects. These findings have major implications for the rational design of novel TCR-based biologics underpinned by rigorous preclinical evaluation.


Assuntos
Antígenos de Neoplasias/imunologia , Linfócitos T CD8-Positivos/imunologia , Proteínas de Neoplasias/imunologia , Neoplasias/imunologia , Peptídeos/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Antígenos de Neoplasias/genética , Linfócitos T CD8-Positivos/patologia , Linhagem Celular Tumoral , Humanos , Proteínas de Neoplasias/genética , Neoplasias/genética , Neoplasias/patologia , Peptídeos/genética , Receptores de Antígenos de Linfócitos T/genética
5.
Hum Reprod ; 29(12): 2756-63, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25336711

RESUMO

STUDY QUESTION: Are circulating microparticles (MPs) altered in young women with polycystic ovary syndrome (PCOS)? SUMMARY ANSWER: Women with PCOS have elevated concentrations of circulating platelet-derived MPs, which exhibit increased annexin V binding and altered microRNA (miR) profiles compared with healthy volunteers. WHAT IS KNOWN ALREADY: Some studies have shown that cardiovascular risk is increased in young women with PCOS but the mechanisms by which this occurs are uncertain. Circulating MPs are elevated in patients with cardiovascular disease but the characteristics of MPs in patients with PCOS are unclear. STUDY DESIGN, SIZE, DURATION: Case-control study comprising 17 women with PCOS (mean ± SD; age 31 ± 7 years, BMI 29 ± 6 kg/m(2)) and 18 healthy volunteers (age 31 ± 6 years, BMI 30 ± 6 kg/m(2)). PARTICIPANTS/MATERIALS, SETTING, METHODS: The study was conducted in a University hospital. Nanoparticle tracking analysis (NTA) and flow cytometry (CD41 platelet, CD11b monocyte, CD144 endothelial) were used to determine MP size, concentration, cellular origin and annexin V positivity (reflecting phosphatidylserine exposure). Fatty acid analysis was performed by gas chromatography and MP miR expression profiles were compared by microarray. MAIN RESULTS AND THE ROLE OF CHANCE: PCOS subjects showed increased MP concentrations compared with healthy volunteers (mean ± SD; 11.5 ± 5 × 10(12)/ml versus 10.0 ± 4 × 10(12)/ml, respectively; P = 0.03), which correlated with the homeostasis model of insulin resistance (r = 0.53, P = 0.03). This difference was predominantly seen in MPs whose size was in the small exosomal range (<150 nm in diameter, P< 0.05). PCOS patients showed a greater percentage of annexin V(+) MPs compared with healthy volunteers (84 ± 18 versus 74 ± 24%, respectively, P = 0.05) but the cellular origin of MPs, which were predominantly platelet-derived (PCOS: 99 ± 0.9%; controls: 99 ± 2.5%), did not differ. MP fatty acid concentration and composition was similar between groups but 16 miRs were differentially expressed (P < 0.05). LIMITATIONS, REASON FOR CAUTION: Patients with PCOS were classified by the Rotterdam criteria, which describes a less severe metabolic phenotype than other definitions of the syndrome. Our findings may thus not be generalizable to all patients with PCOS. MicroRNA expression analysis was only undertaken in an exploratory subset of the overall study population hence, validation of our findings in a larger cohort is mandatory. Furthermore, miR levels were unaltered for the highly expressed miRs and it is unclear whether differences in the lowly expressed miRs carries pathological relevance. WIDER IMPLICATIONS OF THE FINDINGS: This study suggests that women with PCOS have an altered MP profile but further studies are needed to confirm this, to explore the mechanisms by which these alterations develop and to establish whether therapies that improve insulin sensitivity are able to reduce circulating MP concentrations. STUDY FUNDING/COMPETING INTERESTS: The study was funded by grants from the Wales Heart Research Institute and Mrs John Nixon Scholarship. The authors have no conflicts of interest to declare.


Assuntos
Anexina A5/sangue , Plaquetas/metabolismo , Síndrome do Ovário Policístico/metabolismo , Adulto , Estudos de Casos e Controles , Micropartículas Derivadas de Células/metabolismo , Feminino , Humanos , Resistência à Insulina , Fatores de Risco
6.
Clin Exp Immunol ; 177(1): 47-63, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24673376

RESUMO

Fluorochrome-conjugated peptide-major histocompatibility complex (pMHC) multimers are widely used for flow cytometric visualization of antigen-specific T cells. The most common multimers, streptavidin-biotin-based 'tetramers', can be manufactured readily in the laboratory. Unfortunately, there are large differences between the threshold of T cell receptor (TCR) affinity required to capture pMHC tetramers from solution and that which is required for T cell activation. This disparity means that tetramers sometimes fail to stain antigen-specific T cells within a sample, an issue that is particularly problematic when staining tumour-specific, autoimmune or MHC class II-restricted T cells, which often display TCRs of low affinity for pMHC. Here, we compared optimized staining with tetramers and dextramers (dextran-based multimers), with the latter carrying greater numbers of both pMHC and fluorochrome per molecule. Most notably, we find that: (i) dextramers stain more brightly than tetramers; (ii) dextramers outperform tetramers when TCR-pMHC affinity is low; (iii) dextramers outperform tetramers with pMHC class II reagents where there is an absence of co-receptor stabilization; and (iv) dextramer sensitivity is enhanced further by specific protein kinase inhibition. Dextramers are compatible with current state-of-the-art flow cytometry platforms and will probably find particular utility in the fields of autoimmunity and cancer immunology.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Separação Celular/métodos , Complexo Principal de Histocompatibilidade/imunologia , Biotina/química , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD8-Positivos/citologia , Linhagem Celular , Células Clonais , Dextranos/química , Citometria de Fluxo , Corantes Fluorescentes/química , Antígeno HLA-A2/química , Antígeno HLA-DR1/química , Antígeno HLA-DR1/metabolismo , Hemaglutininas Virais/metabolismo , Humanos , Insulina/metabolismo , Fragmentos de Peptídeos/metabolismo , Ligação Proteica , Precursores de Proteínas/metabolismo , Estreptavidina/química , Especificidade do Receptor de Antígeno de Linfócitos T/imunologia , Telomerase/metabolismo
7.
Clin Exp Immunol ; 175(2): 258-67, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24116999

RESUMO

Chimeric antigen receptors (CARs) can mediate redirected lysis of tumour cells in a major histocompatibility complex (MHC)-independent manner, thereby enabling autologous adoptive T cell therapy for a variety of malignant neoplasms. Currently, most CARs incorporate the T cell receptor (TCR) CD3ζ signalling chain; however, the precise mechanisms responsible for CAR-mediated T cell activation are unclear. In this study, we used a series of immunoreceptor tyrosine-based activation motif (ITAM)-mutant and transmembrane-modified receptors to demonstrate that CARs activate T cells both directly via the antigen-ligated signalling chain and indirectly via associated chains within the TCR complex. These observations allowed us to generate new receptors capable of eliciting polyfunctional responses in primary human T cells. This work increases our understanding of CAR function and identifies new avenues for the optimization of CAR-based therapeutic interventions.


Assuntos
Antígenos de Neoplasias/imunologia , Complexo CD3/imunologia , Imunoterapia Adotiva/métodos , Ativação Linfocitária , Receptores de Antígenos de Linfócitos T/imunologia , Proteínas Recombinantes de Fusão/imunologia , Linfócitos T/imunologia , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Complexo CD3/genética , Linhagem Celular , Células HEK293 , Humanos , Motivo de Ativação do Imunorreceptor Baseado em Tirosina/genética , Células Jurkat , Lectinas Tipo C/metabolismo , Neoplasias/imunologia , Neoplasias/terapia , Receptores de Antígenos de Linfócitos T/genética , Proteínas Recombinantes de Fusão/genética , Transdução de Sinais/imunologia , Ativação Transcricional/genética
8.
HIV Med ; 14(4): 247-51, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22998022

RESUMO

OBJECTIVE: The aim of the study was to determine the prevalence and risk factors for HIV-associated fatigue in the era of highly active antiretroviral therapy (HAART). METHODS: A cross-sectional survey of 100 stable HIV-infected out-patients was carried out. Severity of fatigue was measured using the Fatigue Impact Scale (FIS). Symptoms of orthostatic intolerance (dysautonomia) were evaluated using the Orthostatic Grading Scale (OGS). Data for HIV-infected patients were compared with those for 166 uninfected controls and 74 patients with chronic fatigue syndrome (CFS)/myalgic encephalomyelitis (encephalopathy) (ME). RESULTS: Ninety-one per cent of HIV-infected patients were on HAART and 78% had suppressed plasma HIV viral load (≤ 40 HIV-1 RNA copies/mL). Fifty-one per cent of HIV-infected patients reported excessive symptomatic fatigue (FIS ≥ 40), and 28% reported severe fatigue symptoms (FIS ≥ 80). The mean FIS score among HIV-infected patients was 50.8 [standard deviation (SD) 41.9] compared with 13.0 (SD 17.6) in uninfected control subjects, and 92.9 (SD 29.0) in CFS patients (P < 0.001 for comparison of HIV-infected patients and uninfected controls). Among HIV-infected patients, fatigue severity was not significantly associated with current or nadir CD4 lymphocyte count, HIV plasma viral load, or whether on HAART. Prior dideoxynucleoside analogue (d-drug) exposure (P = 0.016) and the presence of clinical lipodystrophy syndrome (P = 0.011) were associated with fatigue. Additionally, fatigue severity correlated strongly with symptomatic orthostatic intolerance (r = 0.65; P < 0.001). CONCLUSIONS: Fatigue is very common and often severe in HIV-infected out-patients, despite viral suppression and good immune function. In a subgroup of patients, prior d-drug exposure may contribute to fatigue, suggesting a metabolic basis. Dysautonomia may also drive fatigue associated with HIV infection, as in other chronic diseases, and CFS/ME, and should be further evaluated with the potential for a shared therapeutic approach.


Assuntos
Terapia Antirretroviral de Alta Atividade , Fadiga/epidemiologia , Infecções por HIV/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Fadiga/etiologia , Síndrome de Fadiga Crônica/epidemiologia , Síndrome de Fadiga Crônica/etiologia , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prevalência , Índice de Gravidade de Doença , Carga Viral , Adulto Jovem
9.
Leukemia ; 25(10): 1587-97, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21647156

RESUMO

The tyrosine kinase inhibitor dasatinib exerts immunosuppressive effects on T-cells and NK-cells in vitro. However, in some dasatinib-treated leukemia patients, clonal lymphocytosis with large granular lymphocyte (LGL) morphology develops, and this is associated with enhanced therapeutic responses. To elucidate the mechanistic basis for this paradoxical observation, we conducted detailed phenotypic and functional analyses of T-cell and NK-cell populations from 25 dasatinib-treated leukemia patients. All tested patients with LGL expansions (15/16) were cytomegalovirus (CMV) immunoglobulin (IgG) seropositive with high frequencies of CMV-specific CD8(+) T-cells; 5/16 LGL patients also experienced symptomatic CMV reactivation during dasatinib therapy. Expanded T-cell and NK-cell populations exhibited late differentiated (CD27(-)CD57(+)) phenotypes; this was associated with a predisposition to apoptosis within the T-cell compartment and impaired NK-cell cytotoxicity. Only 3/9 non-LGL patients were CMV IgG seropositive. Dasatinib inhibited in vitro lymphocyte functions, similarly in LGL patients and controls. Notably, distinct CD8(high) and CD8(low) T-cell subsets were observed in LGL patients; this phenotypic dichotomy was also apparent in CMV-specific CD8(+) T-cell populations, and exhibited features consistent with antigen-driven activation. In addition, plasma levels of IP-10, IL-6, monokine induced by interferon-γ and interleukin-2R were significantly increased in LGL patients. These data provide evidence that dasatinib-associated LGL expansion is linked to CMV reactivation and suggest a potential mechanism for this phenomenon.


Assuntos
Linfócitos T CD8-Positivos/citologia , Diferenciação Celular , Divisão Celular , Citomegalovirus/fisiologia , Células Matadoras Naturais/citologia , Leucemia/induzido quimicamente , Inibidores de Proteínas Quinases/efeitos adversos , Pirimidinas/efeitos adversos , Tiazóis/efeitos adversos , Ativação Viral , Adulto , Idoso , Apoptose , Sequência de Bases , Primers do DNA , Dasatinibe , Feminino , Citometria de Fluxo , Humanos , Leucemia/imunologia , Leucemia/patologia , Leucemia/virologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
Leukemia ; 24(4): 798-805, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20220777

RESUMO

The receptor for hyaluronic acid-mediated motility (RHAMM) is a tumor-associated antigen in chronic lymphocytic leukemia (CLL). CD8(+) T cells primed with the RHAMM-derived epitope R3, which is restricted by human leukocyte antigen (HLA)-A2, effectively lyse RHAMM(+) CLL cells. Therefore, we initiated a phase I clinical trial of R3 peptide vaccination. Six HLA-A2(+) CLL patients were vaccinated four times at biweekly intervals with the R3 peptide (ILSLELMKL; 300 microg per dose) emulsified in incomplete Freund's adjuvant; granulocyte-macrophage colony stimulating factor (100 microg per dose) was administered concomitantly. Detailed immunological analyses were conducted throughout the course of peptide vaccination. No severe adverse events greater than CTC I degrees skin toxicity were observed. Four patients exhibited reduced white blood cell counts during vaccination. In five of six patients, R3-specific CD8(+) T cells were detected with the corresponding peptide/HLA-A2 tetrameric complex; these populations were verified functionally in four of five patients using enzyme-linked immunosorbent spot (ELISpot) assays. In patients with clinical responses, we found increased frequencies of R3-specific CD8(+) T cells that expressed high levels of CD107a and produced both interferon-gamma and granzyme B in response to antigen challenge. Interestingly, vaccination was also associated with the induction of regulatory T cells in four patients. Thus peptide vaccination in six CLL patients was safe and could elicit to some extent specific CD8(+) T-cell responses against the tumor antigen RHAMM.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer/uso terapêutico , Proteínas da Matriz Extracelular/imunologia , Receptores de Hialuronatos/imunologia , Leucemia Linfocítica Crônica de Células B/imunologia , Fragmentos de Peptídeos/uso terapêutico , Linfócitos T Citotóxicos/imunologia , Adulto , Idoso , Vacinas Anticâncer/imunologia , Proliferação de Células , Epitopos de Linfócito T , Estudos de Viabilidade , Feminino , Citometria de Fluxo , Antígeno HLA-A2/imunologia , Antígeno HLA-A2/metabolismo , Humanos , Imunoterapia , Interferon gama/metabolismo , Leucemia Linfocítica Crônica de Células B/terapia , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/imunologia , Linfócitos T Reguladores/imunologia , Vacinação
11.
Mucosal Immunol ; 1(1): 49-58, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19079160

RESUMO

The mechanisms underlying the massive gastrointestinal tract CD4 T-cell depletion in human immunodeficiency virus (HIV) infection are not well understood nor is it clear whether similar depletion is manifest at other mucosal surfaces. Studies of T-cell and virus dynamics in different anatomical sites have begun to illuminate the pathogenesis of HIV-associated disease. Here, we studied depletion and HIV infection frequencies of CD4 T cells from the gastrointestinal tract, bronchoalveolar lavage (BAL), and blood with the frequencies and functional profiles of HIV-specific T cells in these anatomically distinct sites in HIV-infected individuals. The major findings to emerge were as follows: (i) depletion of gastrointestinal CD4 T cells is associated with high frequencies of infected CD4 T cells; (ii) HIV-specific T cells are present at low frequencies in the gastrointestinal tract compared to blood; (iii) BAL CD4 T cells are not massively depleted during the chronic phase; (iv) infection frequencies of BAL CD4 T cells are similar to those in blood; (v) significantly higher frequencies and increased functionality of HIV-specific T cells were observed in BAL compared to blood. Taken together, these data suggest mechanisms for mucosal CD4 T-cell depletion and interventions that might circumvent global depletion of mucosal CD4 T cells.


Assuntos
Síndrome da Imunodeficiência Adquirida/imunologia , Líquido da Lavagem Broncoalveolar/imunologia , Linfócitos T CD4-Positivos/imunologia , HIV/imunologia , Mucosa Intestinal/imunologia , Síndrome da Imunodeficiência Adquirida/sangue , Lavagem Broncoalveolar , Contagem de Linfócito CD4 , Doença Crônica , Feminino , Humanos , Masculino , Especificidade de Órgãos/imunologia
12.
Cytotherapy ; 10(6): 633-41, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18836918

RESUMO

The discovery of new drugs has occasionally led to a better understanding of biologic processes and unforeseen therapeutic applications. One such example is the new group of tyrosine kinase inhibitors, exemplified by the Bcr-Abl inhibitor imatinib (Glivec). In the last 10 years, these so-called 'small molecules' have started to enter the clinic with the promise of cancer treatments targeted at the underlying molecular changes that are responsible for specific malignant phenotypes. The aim of these small molecules has been to avoid the side-effects of systemic chemotherapies and the high morbidity/mortality risks associated with hematopoietic stem cell transplantation. Concurrently, however, increasing evidence has emerged to indicate that these drugs exert profound immunomodulatory effects on T cells and antigen-presenting cells, such as dendritic cells, which play major roles in immune tumor surveillance and the outcome of hematopoietic stem cell transplantation. Targeted tyrosine kinase inhibitor therapy may thus control cancer cell growth both directly and indirectly by changing the immunologic microenvironment. Furthermore, such molecules might help to unravel the complexities of the human immune system and could find therapeutic application in conditions as diverse as autoimmune diseases and certain infectious processes. In this brief review, we discuss recent developments in this fast evolving field.


Assuntos
Células Dendríticas/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Piperazinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Linfócitos T/efeitos dos fármacos , Animais , Benzamidas , Células Dendríticas/imunologia , Humanos , Mesilato de Imatinib , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais , Linfócitos T/imunologia
13.
Mult Scler ; 14(6): 749-58, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18611988

RESUMO

Glatiramer acetate (GA) is believed to induce GA-reactive T cells that secrete anti-inflammatory cytokines at the site of inflammation in multiple sclerosis (MS). However, GA-reactive T cells have not been established from the intrathecal compartment of MS patients, and intrathecal T cells may differ from T cells in blood. Here, we compared the phenotype of GA-reactive T cells from the cerebrospinal fluid (CSF) and blood of five MS patients treated with GA for 3-36 months, and in three of these patients also before treatment. From the CSF of these patients, all 22 T cell lines generated before and all 38 T cell lines generated during treatment were GA-reactive. GA treatment induced a more pronounced anti-inflammatory profile of GA-reactive T cell lines from CSF than from blood. While GA-reactive T cell clones from CSF were restricted by either human leukocyte antigen (HLA) -DR or HLA-DP, only HLA-DR restricted GA-reactive T cell clones were detected in blood. No cross reactivity with myelin proteins was detected in GA-reactive T cell lines or clones from CSF. These results suggest that a selected subset of GA-reactive T cells are present in the intrathecal compartment, and support an anti-inflammatory mechanism of action for GA.


Assuntos
Imunossupressores/administração & dosagem , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Esclerose Múltipla Recidivante-Remitente/imunologia , Peptídeos/administração & dosagem , Células Th1/efeitos dos fármacos , Células Th2/efeitos dos fármacos , Linhagem Celular , Reações Cruzadas/imunologia , Citocinas/metabolismo , Feminino , Acetato de Glatiramer , Antígenos HLA-DP/metabolismo , Antígenos HLA-DR/metabolismo , Humanos , Masculino , Esclerose Múltipla Recidivante-Remitente/líquido cefalorraquidiano , Proteínas da Mielina/imunologia , Células Th1/citologia , Células Th1/metabolismo , Células Th2/citologia , Células Th2/metabolismo
14.
Neurology ; 68(18): 1501-8, 2007 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-17470753

RESUMO

OBJECTIVE: To evaluate the total number of synapses in the stratum radiatum (str rad) of the human hippocampal CA1 subfield in individuals with mild Alzheimer disease (mAD), mild cognitive impairment (MCI), or no cognitive impairment (NCI) and determine if synapse loss is an early event in the progression of the disease. METHODS: Short postmortem autopsy tissue was obtained, and an unbiased stereologic sampling scheme coupled with transmission electron microscopy was used to directly visualize synaptic contacts. RESULTS: Individuals with mAD had fewer synapses (55%) than the other two diagnostic groups. Individuals with MCI had a mean synaptic value that was 18% lower than the NCI group mean. The total number of synapses showed a correlation with several cognitive tests including those involving both immediate and delayed recall. Total synaptic numbers showed no relationship to the subject's Braak stage or to APOE genotype. The volume of the str rad was reduced in mAD vs the other two diagnostic groups that were not different from each other. CONCLUSION: These results strongly support the concept that synapse loss is a structural correlate involved very early in cognitive decline in mild Alzheimer disease (mAD) and supports mild cognitive impairment as a transitional stage between mAD and no cognitive impairment.


Assuntos
Doença de Alzheimer/patologia , Transtornos Cognitivos/patologia , Hipocampo/patologia , Degeneração Neural/patologia , Sinapses/patologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/fisiopatologia , Transtornos Cognitivos/fisiopatologia , Espinhas Dendríticas/patologia , Progressão da Doença , Feminino , Hipocampo/fisiopatologia , Humanos , Masculino , Microscopia Eletrônica de Transmissão , Degeneração Neural/etiologia , Degeneração Neural/fisiopatologia , Valor Preditivo dos Testes , Terminações Pré-Sinápticas/patologia , Prognóstico
15.
Cytotherapy ; 9(3): 245-51, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17464756

RESUMO

BACKGROUND: The curative effects of GvL following transfer of donor-derived T cells during allogeneic stem cell transplantation (SCT) are well established. However, little is known about the nature, origin and kinetics of the anti-leukemic T-cell responses involved. METHODS: We used quantitative real-time PCR (qRT-PCR) for interferongamma mRNA production (IFN-gamma) and PR1/HLA-A*0201 tetramer staining to detect PR1-specific CD8+ T-cell activity in a donor and a patient with CML. Unbiased strand switch anchored RT-PCR was used to further characterize specific clones in PR1 sorted CD8+ T-cell populations. RESULTS: We identified PR1-specific CD8(+) T-cell clones from a donor pre-transplant, and demonstrated their transfer in the recipient's blood post-SCT using molecular tracking of Ag-specific T-cell receptors. PR1-specific CD8(+) T-cell populations were polyclonal, with a range of functional avidities for cognate Ag, and displayed predominantly effector memory phenotype early post-SCT, suggesting active stimulation in vivo. Expansion of these PR1-specific CD8(+) T-cell clones in the recipient was followed by complete remission of CML. DISCUSSION: This report represents the first direct demonstration that PR1-specific CD8(+) T-cell clones can be transferred during SCT, and supports the feasibility of pre-transplant vaccination strategies that aim to boost the number of anti-leukemic T cells in the graft.


Assuntos
Linfócitos T CD8-Positivos/transplante , Efeito Enxerto vs Leucemia , Antígenos HLA-A/imunologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/imunologia , Mieloblastina/imunologia , Transplante de Células-Tronco , Adulto , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Estudos de Viabilidade , Antígeno HLA-A2 , Humanos , Imunofenotipagem , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Masculino , Oligopeptídeos/imunologia
16.
Horm Res ; 68(4): 157-63, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17356292

RESUMO

AIMS: To compare the efficacy of goserelin 10.8 mg (Zoladex LA-ZLA) administered 9-12 weekly with 3.6 mg (Zoladex-Z) given monthly in suppressing pubertal development, and effect on body mass index (BMI). METHODS: Children with central precocious puberty (CPP) treated with Z (n = 34) or ZLA (n = 28) were studied retrospectively. Pubertal scores and BMI SDS during 24 months' treatment were compared. RESULTS: To attain adequate pubertal suppression, more patients on ZLA than Z required increase in injection frequency (p = 0.02) and this was so for 7/8 patients with a structural aetiology for CPP on ZLA and 2/8 on Z. A greater proportion of patients on ZLA had BMI >+2 SDS before (p = 0.05), and at 18 and 24 months (p = 0.02 and 0.04). BMI SDS transiently increased during the first 6 months on ZLA (p = 0.04). CONCLUSION: Both Z and ZLA were effective in suppressing puberty. To achieve adequate suppression, increased injection frequency was more likely with ZLA than Z, and particularly in patients with structural defects. Children with CPP had an elevated BMI at the onset of therapy and ZLA had a transient positive influence on BMI.


Assuntos
Hormônio Liberador de Gonadotropina/análogos & derivados , Gosserrelina/administração & dosagem , Puberdade Precoce/tratamento farmacológico , Estatura/efeitos dos fármacos , Índice de Massa Corporal , Criança , Preparações de Ação Retardada , Esquema de Medicação , Feminino , Crescimento e Desenvolvimento/efeitos dos fármacos , Humanos , Masculino , Estudos Retrospectivos , Resultado do Tratamento
17.
Arch Dis Child ; 90(6): 574-8, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15908619

RESUMO

AIMS AND METHODS: Thyroid function tests were initially carried out on 122 children with Down's syndrome aged 6-14 years and then repeated four to six years later in 103 adolescents (85% of the group of 122) when they were aged 10-20 years (median 14.4 years). At the second test two were hypothyroid and two with isolated raised thyroid stimulating hormone (IR-TSH) were receiving thyroxine. RESULTS: At the first test there were 98 (80%) euthyroid children: 83 were retested and four (5%) had IR-TSH. At the first test 24 had IR-TSH: 20 were retested and 14 (70%) had become normal. Seventeen with IR-TSH on initial testing had a thyrotrophin releasing hormone test within three months; TSH had become normal in eight (47%) of these children. There was no association between reported clinical symptoms and IR-TSH, but there were clear symptoms in one of the two with definite hypothyroidism. CONCLUSIONS: The likelihood ratio for a positive result on second testing when raised TSH and positive antibody status on first testing are combined is 20. This suggests initial testing results could be used as a basis to select a subgroup for further testing at say five yearly intervals unless new symptoms emerge in the interim. It also suggests that yearly screening (as recommended by the American Academy of Pediatrics, 2001) is probably not justified in the first 20 years of life.


Assuntos
Síndrome de Down/fisiopatologia , Hipotireoidismo/diagnóstico , Adolescente , Criança , Síndrome de Down/sangue , Humanos , Hipotireoidismo/tratamento farmacológico , Estudos Longitudinais , Programas de Rastreamento/métodos , Prognóstico , Testes de Função Tireóidea/métodos , Tireotropina/sangue , Tiroxina/uso terapêutico
18.
Clin Exp Immunol ; 139(1): 101-11, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15606619

RESUMO

The bisphosphonates are a novel class of drug that have been registered for various clinical applications worldwide. Bisphosphonates, and in particular the aminobisphosphonates (nBPs), are known to have a number of side-effects including a rise in body temperature and accompanying flu-like symptoms that resemble a typical acute phase response. The mechanism for this response has been partially elucidated and appears to be associated with the release of tumour necrosis factor (TNF)alpha and interleukin (IL)6, although the effector cells that release these cytokines and the mechanism of action remain enigmatic. Here, we show that the nBP-induced acute phase response differs from the typical acute phase response in that CD14+ cells such as monocytes and macrophages are not the primary cytokine producing cells. We show that by inhibiting the mevalonate pathway, nBPs induce rapid and copious production of TNFalpha and IL6 by peripheral blood gammadelta T cells. Prior treatment with statins, which inhibit 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase, blocks nBP-induced production of these proinflammatory cytokines by gammadelta T cells and may offer a means of avoiding the associated acute phase response. In addition, our findings provide a further mechanism for the anti-inflammatory effects attributed to inhibitors of HMG CoA reductase.


Assuntos
Reação de Fase Aguda/imunologia , Anticolesterolemiantes/imunologia , Citocinas/biossíntese , Difosfonatos/imunologia , Naftalenos/imunologia , Linfócitos T/imunologia , Citocinas/imunologia , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/imunologia , Interleucina-6/biossíntese , Interleucina-6/imunologia , Receptores de Lipopolissacarídeos/imunologia , Macrófagos/imunologia , Ácido Mevalônico/imunologia , Ácido Mevalônico/metabolismo , Monócitos/imunologia , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/imunologia
19.
J Clin Endocrinol Metab ; 88(11): 5281-6, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14602762

RESUMO

We here: 1) describe the phenotypic spectrum, including magnetic resonance imaging (MRI) appearances of the pituitary stalk and anterior and posterior pituitary [H-P (hypothalamic-pituitary) axis], in children with optic nerve hypoplasia (ONH) with or without an abnormal septum pellucidum (SP); and 2) define endocrine dysfunction according to the MRI findings. Medical records of 55 children with ONH who had been assessed by ophthalmology and endocrine services were reviewed. All had MRI of the brain and H-P axis. Forty-nine percent of the ONH patients had an abnormal SP on MRI, and 64% had a H-P axis abnormality. Twenty-seven patients (49%) had endocrine dysfunction, and 23 of these had H-P axis abnormality. The frequency of endocrinopathy was higher in patients with an abnormal SP (56%) than a normal SP (39%). Patients were divided into four groups based on SP and H-P axis appearance: 1) both normal; 2) abnormal SP and normal H-P axis; 3) normal SP and abnormal H-P axis; and 4) both abnormal. The frequency of multiple pituitary hormone deficiency was highest (56%) in group 4, lower (35%) in group 3, and even lower (22%) in group 2. Precocious puberty was most common in group 2. None of the patients in group 1 had endocrine dysfunction. Thus, SP and H-P axis appearances on MRI can be used to predict the likely spectrum of endocrinopathy.


Assuntos
Sistema Hipotálamo-Hipofisário/anormalidades , Sistema Hipotálamo-Hipofisário/patologia , Nervo Óptico/anormalidades , Doenças da Hipófise/patologia , Septo Pelúcido/anormalidades , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Nervo Óptico/patologia , Doenças da Hipófise/epidemiologia , Hipófise/anormalidades , Hipófise/patologia , Valor Preditivo dos Testes , Fatores de Risco , Septo Pelúcido/patologia
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