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1.
BMC Med ; 22(1): 144, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38561783

RESUMO

BACKGROUND: Type 2 diabetes in young people is an aggressive disease with a greater risk of complications leading to increased morbidity and mortality during the most productive years of life. Prevalence in the UK and globally is rising yet experience in managing this condition is limited. There are no consensus guidelines in the UK for the assessment and management of paediatric type 2 diabetes. METHODS: Multidisciplinary professionals from The Association of Children's Diabetes Clinicians (ACDC) and the National Type 2 Diabetes Working Group reviewed the evidence base and made recommendations using the Grading Of Recommendations, Assessment, Development and Evaluation (GRADE) methodology. RESULTS AND DISCUSSION: Young people with type 2 diabetes should be managed within a paediatric diabetes team with close working with adult diabetes specialists, primary care and other paediatric specialties. Diagnosis of diabetes type can be challenging with many overlapping features. Diabetes antibodies may be needed to aid diagnosis. Co-morbidities and complications are frequently present at diagnosis and should be managed holistically. Lifestyle change and metformin are the mainstay of early treatment, with some needing additional basal insulin. GLP1 agonists should be used as second-line agents once early ketosis and symptoms are controlled. Glycaemic control improves microvascular but not cardiovascular risk. Reduction in excess adiposity, smoking prevention, increased physical activity and reduction of hypertension and dyslipidaemia are essential to reduce major adverse cardiovascular events. CONCLUSIONS: This evidence-based guideline aims to provide a practical approach in managing this condition in the UK.


Assuntos
Diabetes Mellitus Tipo 2 , Metformina , Adulto , Humanos , Criança , Adolescente , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/terapia , Comorbidade , Obesidade , Reino Unido/epidemiologia
2.
Diabetes Res Clin Pract ; 184: 109196, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35033598

RESUMO

Real-time continuous glucose monitoring (rtCGM) and FreeStyle Libre glucose monitoring systems (isCGM) are new evolving technologies used in the management of Type 1 diabetes. They offer potential to improve diabetes control and reduce hypoglycaemia. rtCGM can be linked to insulin pump providing hybrid closed loop therapy. Families of children and young people are keen to have the benefit from these technologies. These are relatively expensive so it is important that health care professionals, families of children and young people (CYP) with diabetes are adequately trained in the use of these devices. Health care professionals need to be able to make patient selection based on individual needs and preferences to achieve maximum benefit. Association of Children's Diabetes Clinicians (ACDC) developed a comprehensive guideline in 2017 to help identify which patients may be most likely to benefit and how these technologies may be practically implemented. Since then new technologies have been introduced and the use of GCM has expanded in routine clinical practice. This article, aims to provide a practical approach and help identify which patients may be most likely to benefit and how the technology may be implemented in order to maximise the clinical benefits.


Assuntos
Automonitorização da Glicemia , Diabetes Mellitus Tipo 1 , Adolescente , Glicemia , Criança , Diabetes Mellitus Tipo 1/tratamento farmacológico , Humanos , Hipoglicemiantes/uso terapêutico , Sistemas de Infusão de Insulina
4.
Sci Rep ; 8(1): 11158, 2018 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-30042403

RESUMO

A prospective study explored the heterogeneous nature of metastatic melanoma using Multiplex immunohistochemistry (IHC) and flow cytometry (FACS). Multiplex IHC data quantitated immune subset number present intra-tumoral (IT) vs the tumor stroma, plus distance of immune subsets from the tumor margin (TM). In addition, mIHC showed a close association between the presence of IT CD8+ T cells and PDL1 expression in melanoma, which was more prevalent on macrophages than on melanoma cells. In contrast, FACS provided more detailed information regarding the T cell subset differentiation, their activation status and expression of immune checkpoint molecules. Interestingly, mIHC detected significantly higher Treg numbers than FACS and showed preferential CD4+ T cell distribution in the tumor stroma. Based on the mIHC and FACS data, we provide a model which defines metastatic melanoma immune context into four categories using the presence or absence of PDL1+ melanoma cells and/or macrophages, and their location within the tumor or on the periphery, combined with the presence or absence of IT CD8+ T cells. This model interprets melanoma immune context as a spectrum of tumor escape from immune control, and provides a snapshot upon which interpretation of checkpoint blockade inhibitor (CBI) therapy responses can be built.


Assuntos
Imuno-Histoquímica/métodos , Melanoma/imunologia , Melanoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Imunológicos/imunologia , Antineoplásicos Imunológicos/uso terapêutico , Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos/imunologia , Citometria de Fluxo , Humanos , Ipilimumab/imunologia , Ipilimumab/uso terapêutico , Ativação Linfocitária , Linfócitos do Interstício Tumoral , Macrófagos/metabolismo , Melanoma/tratamento farmacológico , Metastasectomia , Pessoa de Meia-Idade , Estudos Prospectivos , Estatísticas não Paramétricas , Linfócitos T Reguladores/imunologia , Evasão Tumoral
5.
Proc Natl Acad Sci U S A ; 115(9): E2068-E2076, 2018 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-29440406

RESUMO

Chimeric antigen receptor T (CAR-T) cells are effective serial killers with a faster off-rate from dying tumor cells than CAR-T cells binding target cells through their T cell receptor (TCR). Here we explored the functional consequences of CAR-mediated signaling using a dual-specific CAR-T cell, where the same cell was triggered via TCR (tcrCTL) or CAR (carCTL). The carCTL immune synapse lacked distinct LFA-1 adhesion rings and was less reliant on LFA to form stable conjugates with target cells. carCTL receptors associated with the synapse were found to be disrupted and formed a convoluted multifocal pattern of Lck microclusters. Both proximal and distal receptor signaling pathways were induced more rapidly and subsequently decreased more rapidly in carCTL than in tcrCTL. The functional consequence of this rapid signaling in carCTL cells included faster lytic granule recruitment to the immune synapse, correlating with faster detachment of the CTL from the target cell. This study provides a mechanism for how CAR-T cells can debulk large tumor burden quickly and may contribute to further refinement of CAR design for enhancing the quality of signaling and programming of the T cell.


Assuntos
Sinapses Imunológicas/imunologia , Neoplasias/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T Citotóxicos/imunologia , Animais , Complexo CD3 , Adesão Celular , Morte Celular , Linhagem Celular Tumoral , Biologia Computacional , Citocinas/metabolismo , Dineínas/química , Ligantes , Ativação Linfocitária , Antígeno-1 Associado à Função Linfocitária/imunologia , Camundongos , Microtúbulos/metabolismo , Transdução de Sinais
6.
J Intellect Disabil Res ; 59(2): 105-15, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24372867

RESUMO

BACKGROUND: A growing literature suggests that people with mild intellectual disability (ID) who have depressed mood may benefit from cognitive-behavioural interventions. There has been some speculation regarding the relative merit of the components of this approach. The aim of this study was to compare (i) cognitive strategies; (ii) behavioural strategies; and (iii) combined cognitive-behavioural (CB) strategies on depressed mood among a sample of 70 individuals with mild ID. METHODS: Staff from three participating agencies received training in how to screen individuals with mild ID for depressive symptoms and risk factors for depression. Depressive symptoms and negative automatic thoughts were assessed prior to and at the conclusion of the intervention, and at 6-month follow-up. The interventions were run in groups by the same therapist. RESULTS: A post-intervention reduction in depression scores was evident in participants of all three interventions, with no significant difference between groups. A significant reduction in negative automatic thoughts post-intervention was evident in the CB combination group and was maintained at follow-up. Examination of clinical effectiveness suggests some advantage of the CB combination in terms of improvement and highlights the possible short term impact of behavioural strategies in comparison with the longer-term potential of cognitive strategies. CONCLUSIONS: The findings support the use of group cognitive-behavioural interventions for addressing symptoms of depression among people with ID. Further research is necessary to determine the effectiveness of components.


Assuntos
Terapia Comportamental/métodos , Transtorno Depressivo/psicologia , Transtorno Depressivo/terapia , Deficiência Intelectual/psicologia , Adulto , Terapia Cognitivo-Comportamental/métodos , Transtorno Depressivo/complicações , Feminino , Seguimentos , Humanos , Deficiência Intelectual/complicações , Masculino , Escalas de Graduação Psiquiátrica , Psicoterapia de Grupo , Resultado do Tratamento , Vitória
7.
Gene Ther ; 17(9): 1105-16, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20428216

RESUMO

The anti-tumor efficacy of adoptively transferred T cells requires their in vivo persistence and memory polarization. It is unknown if human chimeric antigen receptor (CAR)-expressing T cells can also undergo memory polarization. We examined the functional status of CAR CD8(+) T cells, re-directed to Lewis Y antigen (LeY-T), throughout a period of ex vivo expansion. Immediately before culture CD8(+) T cells comprised a mixture of phenotypes including naive (CD45RA(+)/CCR7(+)/CD27(+)/CD28(+)/perforin-), central memory (CM, CD45RA(-)/CCR7(lo)/CD27(+)/CD28(+)/perforin(lo)), effector memory (EM, CD45RA(-)/CCR7(-)/CD27(+)/CD28(+)/perforin(mod)) and effector (Eff, CD45RA(+)/CCR7(-)/CD27(-)/CD28(-)/perforin(hi)) cells. After transduction and expansion culture of peripheral blood mononuclear cells from normal donors or multiple myeloma patients, CD8(+) LeY-T cells polarized to EM- and CM-like phenotype. CD8(+) LeY-T cells differed from starting CD8(+) CM and EM T cells in that CD27, but not CD28, was downregulated. In addition, CD8(+) LeY-T cells expressed high levels of perforin, similar to starting CD8(+) Eff. CD8(+) LeY-T cells also showed hallmarks of both memory and Eff function, underwent homeostatic proliferation in response to interleukin (IL)-15, and showed interferon (IFN)-γ production and cytotoxicity in response to Le-Y antigen on OVCAR-3 (human ovarian adenocarcinoma) cells. This study confirms CD8(+) LeY-T cells have a CM- and EM-like phenotype and heterogeneous function consistent with potential to persist in vivo after adoptive transfer.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Citotoxicidade Imunológica , Memória Imunológica , Receptores de Antígenos/genética , Antígenos CD28/imunologia , Proliferação de Células , Humanos , Interferon gama/metabolismo , Antígenos Comuns de Leucócito/imunologia , Fenótipo , Receptores de Antígenos/imunologia , Receptores de Antígenos/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia
8.
Gene Ther ; 17(5): 678-86, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20200563

RESUMO

We have evaluated the carbohydrate antigen Lewis(Y) (Le(Y)) as a potential target for T-cell immunotherapy of hematological neoplasias. Analysis of 81 primary bone marrow samples revealed moderate Le(Y) expression on plasma cells of myeloma patients and myeloblasts of patients with acute myeloid leukemia (AML) (52 and 46% of cases, respectively). We developed a retroviral vector construct encoding a chimeric T-cell receptor that recognizes the Le(Y) antigen in a major histocompatibility complex-independent manner and delivers co-stimulatory signals to achieve T-cell activation. We have shown efficient transduction of peripheral blood-derived T cells with this construct, resulting in antigen-restricted interferon-gamma secretion and cell lysis of Le(Y)-expressing tumor cells. In vivo activity of gene-modified T cells was demonstrated in the delayed growth of myeloma xenografts in NOD/SCID mice, which prolonged survival. Therefore, targeting Le(Y)-positive malignant cells with T cells expressing a chimeric receptor recognizing Le(Y) was effective both in vitro and in a myeloma mouse model. Consequently, we plan to use T cells manufactured under Good Manufacturing Practice conditions in a phase I immunotherapy study for patients with Le(Y)-positive myeloma or AML.


Assuntos
Terapia Genética/métodos , Imunoterapia Adotiva/métodos , Leucemia Mieloide Aguda/terapia , Antígenos do Grupo Sanguíneo de Lewis/imunologia , Mieloma Múltiplo/terapia , Receptores de Antígenos de Linfócitos T/genética , Linfócitos T/transplante , Animais , Feminino , Vetores Genéticos , Humanos , Interferon gama/metabolismo , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Receptores de Antígenos de Linfócitos T/imunologia , Retroviridae/genética , Linfócitos T/imunologia , Transdução Genética
9.
Gene Ther ; 16(5): 596-604, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19158846

RESUMO

Human T lymphocytes can be redirected with a new defined specificity by expression of a chimeric T-cell receptor (immunoreceptor) for the use in adoptive immunotherapy of cancer. Whereas standard procedures use retroviral gene transduction to constitutively express immunoreceptors in T cells, we here explored for the first time mRNA electroporation to achieve transient immunoreceptor expression, and thereby minimizing the risk of persistence of potential autoaggression. CD4(+) and CD8(+) T cells were efficiently transfected with immunoreceptors specific for ErbB2 and CEA. The immunoreceptor expression was transient with half-maximal expression at day 2 and no detectable immunoreceptor expression at day 9 after electroporation. Immunoreceptor-transfected T cells were specifically activated upon coincubation with ErbB2(+) and CEA(+) tumor cells, respectively, resulting in secretion of interferon-gamma (IFNgamma), interleukin-2 (IL-2), and tumor necrosis factor-alpha (TNFalpha). Furthermore, immunoreceptor-transfected CD8(+) T cells specifically lysed ErbB2(+) and CEA(+) tumor cells, respectively. The RNA-transfected T cells retained their cytotoxic function after 2 days of activation and exhibited cytolytic activities like retrovirally transduced T cells. RNA electroporation of T cells thereby provides a versatile tool for transient immunoreceptor expression, which may be of advantage in avoiding the persistence of unintended autoaggression.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Imunoterapia Adotiva/métodos , Neoplasias/imunologia , Receptores Imunológicos/biossíntese , Citotoxicidade Imunológica , Eletroporação , Vetores Genéticos , Humanos , Ativação Linfocitária , Neoplasias/patologia , RNA Mensageiro/genética , Receptores Imunológicos/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Retroviridae/genética , Transfecção , Células Tumorais Cultivadas
10.
Gene Ther ; 15(14): 1056-66, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18369322

RESUMO

There is considerable concern regarding the transforming potential of retroviral vectors currently used for gene therapy, with evidence that retroviral integration can lead to leukemia in recipients of gene-modified stem cells. However, it is not clear whether retroviral-mediated transduction of T cells can lead to malignancy. We transduced mouse T cells with a Moloney murine retroviral gene construct and transferred them into congenic mice, which were preconditioned to enhance the engraftment of transferred T cells. Recipients were then observed long-term for evidence of cancer. Transferred T cells persisted in mice throughout life at levels up to 17% with gene copy numbers up to 5.89 x 10(5) per million splenocytes. Mice receiving gene-modified T cells developed tumors at a similar rate as control mice that did not receive T cells, and tumors in both groups of mice were of a similar range of histologies. Hematological malignancies comprised approximately 60% of cancers, and the remaining cancers consisted largely of carcinomas. Importantly, the incidence of lymphomas was similar in both groups of mice, and no lymphomas were found to be of donor T-cell origin. This study indicates that the use of retroviral vectors to transduce T cells does not lead to malignant transformation.


Assuntos
Transferência Adotiva , Terapia Genética/efeitos adversos , Vetores Genéticos/administração & dosagem , Vírus da Leucemia Murina de Moloney/fisiologia , Linfócitos T/virologia , Animais , Transformação Celular Viral , Leucemia/virologia , Linfoma/virologia , Camundongos , Camundongos SCID , Vírus da Leucemia Murina de Moloney/genética , Neoplasias/imunologia , Neoplasias/patologia , Linfócitos T/transplante , Tempo , Transdução Genética/métodos , Transgenes
11.
Cancer Gene Ther ; 14(9): 773-80, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17599092

RESUMO

Dendritic cells (DC) perform an important role in the initiation of the immune response through the local secretion of inflammatory mediators within diseased tissue in response to Toll-like receptor (TLR) ligation. However, DC vaccine strategies fail to make use of this capability against cancer. To harness the TLR response capability of DC against cancer, we tested a series of recombinant genes for their ability to redirect DC function specifically against a tumor-associated antigen. Each gene encoded a cell surface chimeric protein made up of extracellular single-chain immunoglobulin anti-erbB2 linked to an intracellular TLR-signaling component composed of either myeloid differentiation factor 88, interleukin-1 receptor-associated kinase-1 (IRAK-1) or the cytoplasmic domain of TLR4. Each gene was expressed in the DC line, JAWS II, to a similar degree following retroviral transduction. However, only the chimera containing IRAK-1 was able to mediate interleukin-12 and tumor necrosis factor-alpha secretion. Since TLR engagement can also activate DC and enhance their ability to stimulate T cells, we ligated the chimeric anti-erbB2-IRAK-1 receptor and determined the effect on the stimulation of T cells. We found that JAWS II cells triggered through chimeric anti-erbB2-IRAK-1 displayed an enhanced ability to stimulate ovalbumin-specific OT-II CD4(+) T cells. This first description of the generation of tumor-reactive DC may lead to the development of new cell-based vaccines that can act at both the tumor site to induce danger and at the lymph node to stimulate a specific T-cell response.


Assuntos
Células Dendríticas/metabolismo , Receptor ErbB-2/metabolismo , Transdução de Sinais/genética , Receptores Toll-Like/metabolismo , Animais , Linhagem Celular Tumoral , Células Dendríticas/imunologia , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Ativação Linfocitária , Camundongos
12.
Cancer Gene Ther ; 14(5): 499-508, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17332777

RESUMO

Activation and expansion of T cells are important in disease resolution, but tumors do not usually satisfy these immune requirements. Therefore, we employed a novel strategy whereby dual-specific T cells were generated that could respond to both tumor and influenza virus, reasoning that immunization with influenza virus would activate and expand tumor-specific cells, and inhibit tumor growth. Dual-specific T cells were generated by gene modification of influenza virus-specific mouse T cells with a chimeric gene-encoding reactivity against the erbB2 tumor-associated antigen. Dual-specific T cells were demonstrated to respond against both tumor and influenza in vitro, and expanded in vitro in response to influenza to a much greater degree than in response to tumor cells. Following adoptive transfer and immunization of tumor-bearing mice with influenza virus, dual-specific T cells expanded greatly in numbers in the peritoneal cavity and spleen. This resulted in a significant increase in time of survival of mice. However, tumors were not eradicated, which may have been due to the observed poor penetration of tumor by T cells. This is the first demonstration that the potent immunogenic nature of an infectious agent can be utilized to directly impact on T-cell expansion and activity against tumor in vivo.


Assuntos
Imunoterapia Adotiva/métodos , Neoplasias Mamárias Animais/terapia , Orthomyxoviridae/imunologia , Receptor ErbB-2/antagonistas & inibidores , Linfócitos T/transplante , Animais , Antígenos de Neoplasias/imunologia , Camundongos , Camundongos Endogâmicos , Receptor ErbB-2/imunologia , Linfócitos T/imunologia
13.
Diabet Med ; 22(5): 645-7, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15842523

RESUMO

BACKGROUND: Diabetic ketoacidosis (DKA) is a common mode of presentation of diabetes mellitus in children, accounting for 26% of new cases. Rarely, children with diabetes may develop other forms of metabolic decompensation associated with hyperglycaemia and hyperosmolality. Hyperglycaemia and hyperosmolality without ketoacidosis has high mortality in adults, although there is no data on mortality in children. CASE REPORTS: We describe three children who presented to Birmingham Children's Hospital and were initially suspected to have DKA. Each child was severely hyperglycaemic and hyperosmolar but without significant ketosis or acidosis. In two of the three children, the hyperosmolar state was associated with the ingestion of large volumes of high calorie fluids preceding the presentation. These children were exquisitely sensitive to insulin and may be at a significantly higher risk of cerebral oedema in view of their hyperosmolar state. CONCLUSIONS: Hyperosmolar hyperglycaemia is a serious and rare complication at presentation of diabetes in children, and should be distinguished from DKA. These children are at an increased risk of cerebral oedema compared with DKA, and one should have a low threshold for suspicion of this complication.


Assuntos
Diabetes Mellitus Tipo 1/complicações , Coma Hiperglicêmico Hiperosmolar não Cetótico/terapia , Adolescente , Edema Encefálico/prevenção & controle , Cetoacidose Diabética/diagnóstico , Feminino , Humanos , Coma Hiperglicêmico Hiperosmolar não Cetótico/complicações , Coma Hiperglicêmico Hiperosmolar não Cetótico/diagnóstico , Masculino , Resultado do Tratamento
15.
Gene Ther ; 9(16): 1085-92, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12140736

RESUMO

Genetic modification of human lymphocytes is being employed in strategies to correct enzyme deficiencies, encode cytokines and to redirect lymphocytes to antigenic targets other than those encoded by their endogenous T cell receptor. However, expression of transgenes in primary lymphocytes is generally low. Reasoning that vector modification may lead to increased transgene expression and subsequent increases in function, we have performed two retroviral vector modifications and report their effect on the functional expression in primary lymphocytes. A chimeric receptor specific for the colon carcinoma-associated antigen, EGP40, was initially incorporated into the retroviral vector LXSN. In this vector, receptor expression is driven by the Moloney murine leukemia virus LTR, and neomycin phosphotransferase expression driven by the SV40 promoter. Replacement of SV40 with an internal ribosomal entry site (IRES) increased the transgene activity of a mouse T cell line and human PBL as judged by increased cytokine release in response to antigen positive target cells. A further increase in transgene function was generated by the additional incorporation of a splice acceptor motif into the construct. Human PBL transduced with vector incorporating both IRES and intron were consistently more effective at lysing antigen positive colorectal carcinoma cells.


Assuntos
Antígenos de Neoplasias/genética , Moléculas de Adesão Celular/genética , Neoplasias do Colo/patologia , Terapia Genética/métodos , Vetores Genéticos/genética , Imunoterapia/métodos , Adulto , Animais , Antígenos de Neoplasias/metabolismo , Moléculas de Adesão Celular/metabolismo , Neoplasias do Colo/imunologia , Citotoxicidade Imunológica , Molécula de Adesão da Célula Epitelial , Regulação da Expressão Gênica , Fator Estimulador de Colônias de Granulócitos e Macrófagos/biossíntese , Humanos , Imunofenotipagem , Interferon gama/biossíntese , Camundongos , Vírus da Leucemia Murina de Moloney/genética , Sítios de Splice de RNA , Transdução Genética , Transgenes/genética , Células Tumorais Cultivadas
16.
Cancer Res ; 61(21): 7920-4, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11691813

RESUMO

Endogenous retroviral gene products have been found in some human tumors, and therefore, may serve as antigens for immunotherapy approaches. The murine colorectal carcinoma CT26 and melanoma B16 have recently been found to express the endogenous retroviral gene products gp70 and p15E, respectively, that can serve as antigens recognized by T cells. To date, though, there has been no demonstration of tumor treatment using an endogenous retroviral protein. In this study, we demonstrate that mice immunized with recombinant vaccinia encoding the gp70 H2-L(d)-restricted minimal determinant were protected from CT26 tumor challenge. Splenocytes from mice immunized with vaccinia gp70 specifically secreted IFN-gamma in response to gp70 peptide-pulsed stimulators. Although this strategy could protect against subsequent tumor challenge, it was ineffective against established tumors. Therefore, to investigate the treatment of established CT26 or B16 lung metastases, mice were treated with cultured dendritic cells (DCs) pulsed with gp70 or p15E peptide. Significant inhibition of established lung metastases required immunization with peptide-pulsed DCs pretreated with CD40 ligand that has been demonstrated to increase the T-cell stimulatory activity of DCs. The ability to immunize against endogenous retroviral tumor antigens may have relevance in the induction of antitumor immunity for some human cancers.


Assuntos
Antígenos de Neoplasias/imunologia , Antígenos Virais/imunologia , Vacinas Anticâncer/imunologia , Proteínas Oncogênicas de Retroviridae/imunologia , Proteínas do Envelope Viral/imunologia , Animais , Antígenos de Neoplasias/genética , Antígenos Virais/genética , Ligante de CD40/imunologia , Vacinas Anticâncer/genética , Neoplasias do Colo/terapia , Células Dendríticas/imunologia , Imunoterapia Adotiva , Neoplasias Pulmonares/secundário , Neoplasias Pulmonares/terapia , Melanoma Experimental/secundário , Melanoma Experimental/terapia , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Oncogênicas de Retroviridae/genética , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Vaccinia virus/genética , Vaccinia virus/imunologia , Proteínas do Envelope Viral/genética
17.
Mol Plant Microbe Interact ; 14(12): 1368-75, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11768531

RESUMO

Obligate plant-pathogenic fungi have proved extremely difficult to characterize with molecular genetics because they cannot be cultured away from host plants and only can be manipulated experimentally in limited circumstances. Previously, in order to characterize signal transduction processes during infection-related development of the powdery mildew fungus Blumeria graminis (syn. Erysiphe graminis) f. sp. hordei, we described a gene similar to the catalytic subunit of cyclic AMP-dependent protein kinase A (here renamed Bka1). Functional characterization of this gene has been achieved by expression in a deltacpkA mutant of the nonobligate pathogen Magnaporthe grisea. This nonpathogenic M. grisea deltacpkA mutant displays delayed and incomplete appressorium development, suggesting a role for PKA-c in the signal transduction processes that control the maturation of infection cells. Transformation of the deltacpkA mutant with the mildew Bka1 open reading frame, controlled by the M. grisea MPG1 promoter, restored pathogenicity and appressorium maturation kinetics. The results provide, to our knowledge, the first functional genetic analysis of pathogenicity in an obligate pathogen and highlight the remarkable conservation of signaling components regulating infection-related development in pathogenic fungi.


Assuntos
Proteínas Arqueais , Ascomicetos/genética , Proteínas Quinases Dependentes de AMP Cíclico/genética , Teste de Complementação Genética , Magnaporthe/genética , Chaperonas Moleculares/genética , Mutação , Plantas/microbiologia , Ascomicetos/fisiologia , Primers do DNA , Hordeum/microbiologia , Magnaporthe/fisiologia
18.
Hum Gene Ther ; 11(18): 2445-52, 2000 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-11119416

RESUMO

The destruction of newly forming tumor vasculature is a promising approach to inhibit tumor growth. The goal of the present study was to investigate whether human lymphocytes gene modified to express a chimeric receptor specific for the angiogenic endothelial cell receptor, KDR, could react against KDR(+) cells. Gene-modified lymphocytes specifically lysed KDR(+) cells and secreted cytokines in response to KDR(+) target cells including human umbilical vein endothelial cells (HUVECs). Anti-KDR lymphocytes induced HUVECs to secrete the chemokine interleukin 8 and upregulate the adhesion molecules VCAM and E-selectin, which may be important in the recruitment of further immune effector cells to tumor. These KDR-specific lymphocytes may be useful in the adoptive immunotherapy of a broad range of cancers by inducing immune-mediated destruction of tumor neovasculature.


Assuntos
Neoplasias/irrigação sanguínea , Neovascularização Patológica , Receptores Proteína Tirosina Quinases/genética , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de Fatores de Crescimento/genética , Receptores de Fatores de Crescimento/metabolismo , Linfócitos T/metabolismo , Antígenos CD28/genética , Adesão Celular , Linhagem Celular , Células Cultivadas , Citocinas/biossíntese , Selectina E/metabolismo , Endotélio Vascular/citologia , Citometria de Fluxo , Técnicas de Transferência de Genes , Humanos , Interleucina-8/biossíntese , Estrutura Terciária de Proteína , Receptores Fc/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular , Transdução Genética , Veias Umbilicais/citologia , Regulação para Cima , Molécula 1 de Adesão de Célula Vascular/metabolismo
19.
Cancer Gene Ther ; 7(2): 284-91, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10770638

RESUMO

Transduction with chimeric T-cell receptor genes can be used to redirect primary T lymphocytes to recognize specific antigens (Ags), including ovarian and breast cancer Ags. To extend this approach to colon cancer we report here redirection of T cells using a chimeric receptor recognizing the colon cancer-associated Ag EGP40. Chimeric T cell receptors were constructed by ligating single-chain genes of either of two EGP40-specific monoclonal antibodies (CO17.1 A, GA733) to the Fc receptor gamma-signaling chain. Retroviral vectors incorporating these constructs were used to transduce a murine T-cell line and human peripheral blood lymphocytes. These modified T cells were analyzed for specific recognition of colon cancer lines by measuring cytokine release and lytic activity against tumor targets. Murine lymphocytes transduced with the chimeric receptor based on GA733, but not CO17.1A, released cytokine specifically in response to EGP40-expressing colon cancer cell lines. Recognition of colon cancer targets by murine lymphocytes was blocked by the addition of GA733 antibody or soluble EGP40 Ag, confirming that colon cancer recognition is based on specific chimeric receptor-Ag interaction. Human lymphocytes transduced with chimeric GA733 specifically recognized colon carcinoma cells in cytokine release assays and lysed EGP40-expressing tumor cells. Genetic modification of T cells can be used to redirect T cells against EGP40-expressing tumor cells. The expression of chimeric GA733 in the autologous lymphocytes of patients may provide a source of tumor-reactive cells with therapeutic application against colon cancer.


Assuntos
Neoplasias do Colo/imunologia , Neoplasias do Colo/metabolismo , Receptores de Antígenos de Linfócitos T/genética , Proteínas Recombinantes de Fusão/genética , Linfócitos T/imunologia , Linfócitos T/metabolismo , Transfecção/imunologia , Células 3T3 , Adulto , Animais , Anticorpos Monoclonais/metabolismo , Antígenos de Neoplasias/biossíntese , Antígenos de Neoplasias/metabolismo , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/metabolismo , Moléculas de Adesão Celular/biossíntese , Moléculas de Adesão Celular/metabolismo , Linhagem Celular , Neoplasias do Colo/genética , Neoplasias do Colo/terapia , Molécula de Adesão da Célula Epitelial , Humanos , Células K562 , Camundongos , Receptores de Antígenos de Linfócitos T/biossíntese , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores de IgG/metabolismo , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/metabolismo , Linfócitos T/virologia , Células Tumorais Cultivadas
20.
Cancer Immunol Immunother ; 47(5): 278-86, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10022472

RESUMO

A chimeric receptor, consisting of the single-chain variable (scFv) domains of an anti-erbB-2 mAb linked via a CD8 membrane-proximal hinge to the Fc receptor gamma chain, was expressed in the mouse cytotoxic T lymphocyte (CTL) hybridoma cell line, MD45. This cell line was grafted with the additional specificity to recognise and bind erbB-2-expressing breast carcinoma target cells T47D, MCF-7 and BT-20 in a non-MHC-restricted manner. Tumour cell lysis was antigen-specific since erbB-2-negative tumours were insensitive to lysis by MD45-scFv-anti-erbB-2-gamma clones, and lysis of erbB-2+ tumour targets was inhibited in the presence of an anti-erbB-2 mAb. Furthermore, target cell death correlated with the level of chimeric receptor expression on the effector MD45 subclones. Redirected MD45 CTL utilised Fas ligand to induce target cell death since soluble Fas-Fc fusion protein completely inhibited cytolysis. The sensitivity of tumour target cells to Fas ligand was further enhanced by treating them with interferon-gamma, a regulator of Fas and downstream signalling components of the Fas pathway. Overall, this study has demonstrated the requirement for successful activation of Fas ligand function in conjunction with cytokine treatment for effective lysis of breast carcinoma target cells mediated by redirected CTL.


Assuntos
Antígenos de Superfície/metabolismo , Citotoxicidade Imunológica/imunologia , Glicoproteínas de Membrana/metabolismo , Neoplasias/imunologia , Receptor ErbB-2/imunologia , Linfócitos T Citotóxicos/imunologia , Receptor fas/metabolismo , Animais , Células COS , Proteína Ligante Fas , Humanos , Camundongos , Células Tumorais Cultivadas
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