RESUMEN
Terrestrial and sub-Neptune planets are expected to form in the inner (less than 10 AU) regions of protoplanetary disks1. Water plays a key role in their formation2-4, although it is yet unclear whether water molecules are formed in situ or transported from the outer disk5,6. So far Spitzer Space Telescope observations have only provided water luminosity upper limits for dust-depleted inner disks7, similar to PDS 70, the first system with direct confirmation of protoplanet presence8,9. Here we report JWST observations of PDS 70, a benchmark target to search for water in a disk hosting a large (approximately 54 AU) planet-carved gap separating an inner and outer disk10,11. Our findings show water in the inner disk of PDS 70. This implies that potential terrestrial planets forming therein have access to a water reservoir. The column densities of water vapour suggest in-situ formation via a reaction sequence involving O, H2 and/or OH, and survival through water self-shielding5. This is also supported by the presence of CO2 emission, another molecule sensitive to ultraviolet photodissociation. Dust shielding, and replenishment of both gas and small dust from the outer disk, may also play a role in sustaining the water reservoir12. Our observations also reveal a strong variability of the mid-infrared spectral energy distribution, pointing to a change of inner disk geometry.
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BACKGROUND: The results of trans-sphenoidal surgery (TSS) in Cushing's disease (CD) vary widely depending upon patient characteristics as well as surgical experience. Patients in India are often referred late to referral centers. We studied the rates of remission and endocrine deficiencies after TSS in patients with CD presenting to a referral hospital in India. METHODS: Sixty consecutive patients (45 females, median age 24.5 years) who underwent TSS between 2000 and 2015 were studied. The median (range) duration of follow-up was 40 (3-138) months. Initial and long-term remission and relapse rates and pituitary hypofunction post-TSS were evaluated. RESULTS: Eighteen (30%) patients harbored macroadenomas. Twenty-eight (47%) patients achieved remission in the immediate post-operative period (8 AM serum cortisol < 140 nmol/l), while a higher remission rate was noted at 6 months (39/54 patients, 72%). At 1 year 70% patients and at final follow-up [median duration 40 (range 3-138) months], 58% of patients were in remission. No pre- or post-surgical variables were consistently associated with remission, except for the 8-AM serum cortisol level on the fifth day after surgery. Seven (18%) patients relapsed on follow-up, including five patients who had fifth post-operative day 8 AM serum cortisol < 140 nmol/l. Twelve (25%) patients newly developed hypothyroidism and one (1.6%) patient developed amenorrhoea after TSS. CONCLUSION: Remission rate at 6 months was higher than immediately after TSS. A significant proportion of patients relapsed, thus necessitating life-long follow-up. New-onset hypothyroidism was frequent after TSS.
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Hipotiroidismo/epidemiología , Procedimientos Neuroquirúrgicos/métodos , Hipersecreción de la Hormona Adrenocorticotrópica Pituitaria (HACT)/cirugía , Complicaciones Posoperatorias/epidemiología , Adulto , Femenino , Humanos , Hipotiroidismo/etiología , India , Masculino , Procedimientos Neuroquirúrgicos/efectos adversos , Complicaciones Posoperatorias/etiología , Hueso Esfenoides/cirugíaRESUMEN
Inflammatory bowel disease (IBD) is a poorly understood chronic immune disorder for which there is no medical cure. Milk and colostrum are rich sources of bioactives with immunomodulatory properties. Here we compared the therapeutic effects of oral delivery of bovine milk-derived iron-saturated lactoferrin (Fe-bLF), angiogenin, osteopontin (OPN), colostrum whey protein, Modulen IBD (Nestle Healthsciences, Rhodes, Australia), and cis-9,trans-11 conjugated linoleic acid (CLA)-enriched milk fat in a mouse model of dextran sulfate-induced colitis. The CLA-enriched milk fat significantly increased mouse body weights after 24d of treatment, reduced epithelium damage, and downregulated the expression of proinflammatory cytokines and nitrous oxide. Modulen IBD most effectively decreased the clinical score at d 12, and Modulen IBD and OPN most effectively lowered the inflammatory score. Myeloperoxidase activity that denotes neutrophil infiltration was significantly lower in mice fed Modulen IBD, OPN, angiogenin, and Fe-bLF. A significant decrease in the numbers of T cells, natural killer cells, dendritic cells, and a significant decrease in cytokine expression were observed in mice fed the treatment diets compared with dextran sulfate administered mice. The Fe-bLF, CLA-enriched milk fat, and Modulen IBD inhibited intestinal angiogenesis. In summary, each of the milk components attenuated IBD in mice, but with differing effectiveness against specific disease parameters.
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Colitis/tratamiento farmacológico , Calostro/química , Proteínas de la Leche/farmacología , Leche/química , Animales , Australia , Enfermedad Crónica , Colitis/inducido químicamente , Citocinas/metabolismo , Productos Lácteos , Sulfato de Dextran/efectos adversos , Modelos Animales de Enfermedad , Glucolípidos/farmacología , Glicoproteínas/farmacología , Lactoferrina/farmacología , Ácidos Linoleicos Conjugados/farmacología , Gotas Lipídicas , Masculino , Ratones , Ratones Endogámicos BALB C , Óxido Nitroso/metabolismo , Osteopontina/farmacología , Ribonucleasa Pancreática/farmacología , Proteína de Suero de Leche/farmacologíaRESUMEN
Very-low-mass stars (those less than 0.3 solar masses) host orbiting terrestrial planets more frequently than other types of stars. The compositions of those planets are largely unknown but are expected to relate to the protoplanetary disk in which they form. We used James Webb Space Telescope mid-infrared spectroscopy to investigate the chemical composition of the planet-forming disk around ISO-ChaI 147, a 0.11-solar-mass star. The inner disk has a carbon-rich chemistry; we identified emission from 13 carbon-bearing molecules, including ethane and benzene. The high column densities of hydrocarbons indicate that the observations probe deep into the disk. The high carbon-to-oxygen ratio indicates radial transport of material within the disk, which we predict would affect the bulk composition of any planets forming in the disk.
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BACKGROUND: It has been argued that a reduction in the Western diet of anti-inflammatory unsaturated lipids, such as n-3 polyunsaturated fatty acids, has contributed to the increase in the frequency and severity of allergic diseases. OBJECTIVE: We investigated whether feeding milk fat enriched in conjugated linoleic acid and vaccenic acids (VAs) ('enriched' milk fat), produced by supplementing the diet of pasture-fed cows with fish and sunflower oil, will prevent development of allergic airway responses. METHODS: C57BL/6 mice were fed a control diet containing soybean oil and diets supplemented with milk lipids. They were sensitized by intraperitoneal injection of ovalbumin (OVA) on days 14 and 28, and challenged intranasally with OVA on day 42. Bronchoalveolar lavage fluid, lung tissues and serum samples were collected 6 days after the intranasal challenge. RESULTS: Feeding of enriched milk fat led to marked suppression of airway inflammation as evidenced by reductions in eosinophilia and lymphocytosis in the airways, compared with feeding of normal milk fat and control diet. Enriched milk fat significantly reduced circulating allergen-specific IgE and IgG1 levels, together with reductions in bronchoalveolar lavage fluid of IL-5 and CCL11. Treatment significantly inhibited changes in the airway including airway epithelial cell hypertrophy, goblet cell metaplasia and mucus hypersecretion. The two major components of enriched milk fat, cis-9, trans-11 conjugated linoleic acid and VA, inhibited airway inflammation when fed together to mice, whereas alone they were not effective. CONCLUSION: Milk fat enriched in conjugated linoleic and VAs suppresses inflammation and changes to the airways in an animal model of allergic airway disease.
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Grasas/inmunología , Hipersensibilidad/inmunología , Ácido Linoleico/inmunología , Enfermedades Pulmonares Obstructivas/inmunología , Enfermedades Pulmonares Obstructivas/patología , Leche/inmunología , Ácidos Oléicos/inmunología , Alérgenos/inmunología , Animales , Supervivencia Celular , Quimiocina CCL11/biosíntesis , Eosinófilos/citología , Eosinófilos/inmunología , Femenino , Hipersensibilidad/metabolismo , Hipersensibilidad/patología , Inmunoglobulinas/biosíntesis , Inmunoglobulinas/inmunología , Interleucina-5/biosíntesis , Enfermedades Pulmonares Obstructivas/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BLRESUMEN
Engineering contributions have played an important role in the rise and evolution of cellular biology. Engineering technologies have helped biologists to explore the living organisms at cellular and molecular levels, and have created new opportunities to tackle the unsolved biological problems. There is now a growing demand to further expand the role of engineering in cellular biology research. For an engineer to play an effective role in cellular biology, the first essential step is to understand the cells and their components. However, the stumbling block of this step is to comprehend the information given in the cellular biology literature because it best suits the readers with a biological background. This paper aims to overcome this bottleneck by describing the human cell components as micro-plants that form cells as micro-bio-factories. This concept can accelerate the engineers' comprehension of the subject. In this paper, first the structure and function of different cell components are described. In addition, the engineering attempts to mimic various cell components through numerical modelling or physical implementation are highlighted. Next, the interaction of different cell components that facilitate complicated chemical processes, such as energy generation and protein synthesis, are described. These complex interactions are translated into simple flow diagrams, generally used by engineers to represent multi-component processes.
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Ingeniería/métodos , Células Eucariotas/citología , Células Eucariotas/fisiología , Biotecnología/métodos , Metabolismo Energético/fisiología , Humanos , Modelos Biológicos , Orgánulos/fisiología , Biosíntesis de Proteínas/fisiologíaRESUMEN
BACKGROUND: Survivin, a member of the inhibitor of apoptosis (IAP) protein family, is detectable in most types of cancer, and its presence is associated with a poor prognosis. We determined the effects of gene-based therapies that inhibit survivin function in a mouse tumor model. METHODS: Using five to six mice per treatment group, we injected tumors derived from mouse EL-4 thymic lymphoma cells with plasmids encoding antisense survivin, a dominant-negative mutant survivin, and the T-cell costimulator B7-1. Expression of endogenous survivin and the proteins encoded by the injected plasmids were examined by immunohistochemical staining of tumor sections and by western blot and flow cytometry analyses of isolated tumor cells. Tumor growth, the generation of antitumor cytotoxic T-lymphocyte (CTL) activity, apoptosis, and the contribution of leukocyte subsets to antitumor activity were measured. All statistical tests were two-sided. RESULTS: Large (1.0-cm diameter) tumors had approximately 10-fold more survivin than small (0.2-cm diameter) tumors. At 28 days after injection, antisense and dominant-negative mutant survivin plasmids statistically significantly inhibited the growth of both small (P =.006 and P =.0018, respectively) and large (P<.001 for both plasmids) EL-4 tumors compared with tumors injected with empty plasmid. The growth of large tumors was further inhibited by intratumoral injection with antisense survivin and B7-1 (P =.004); thus, inhibition of survivin expression renders large tumors susceptible to B7-1-mediated immunotherapy. Mice whose tumors were completely eradicated by injection of B7-1 remained tumor free for 26 days after re-injection with EL-4 cells (when the experiment ended). Compared with tumors injected with empty plasmid, tumors injected with survivin-based plasmids had increased apoptosis, and animals bearing such tumors generated more antitumor CTLs. CONCLUSION: Intratumoral injection of plasmids that block survivin expression and stimulate the generation of tumor-specific CTLs may be beneficial for the treatment of large lymphomas.
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Antígeno B7-1/uso terapéutico , Proteínas Cromosómicas no Histona/fisiología , ADN sin Sentido/uso terapéutico , Terapia Genética , Inmunoterapia , Linfoma no Hodgkin/tratamiento farmacológico , Proteínas Asociadas a Microtúbulos , Proteínas de Neoplasias/fisiología , Neoplasias del Timo/terapia , Animales , Anticuerpos Monoclonales/administración & dosificación , Apoptosis , Antígeno B7-1/administración & dosificación , Proteínas Cromosómicas no Histona/antagonistas & inhibidores , Proteínas Cromosómicas no Histona/biosíntesis , Proteínas Cromosómicas no Histona/genética , Terapia Combinada , ADN sin Sentido/administración & dosificación , ADN sin Sentido/genética , Progresión de la Enfermedad , Femenino , Dosificación de Gen , Regulación Neoplásica de la Expresión Génica , Marcación de Gen , Genes Dominantes , Vectores Genéticos/administración & dosificación , Vectores Genéticos/uso terapéutico , Rechazo de Injerto/inmunología , Proteínas Inhibidoras de la Apoptosis , Inyecciones Intralesiones , Depleción Linfocítica , Subgrupos Linfocitarios/inmunología , Subgrupos Linfocitarios/patología , Linfocitos Infiltrantes de Tumor , Linfoma no Hodgkin/inmunología , Linfoma no Hodgkin/patología , Linfoma no Hodgkin/terapia , Ratones , Ratones Endogámicos C57BL , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , Trasplante de Neoplasias , Survivin , Linfocitos T Citotóxicos/inmunología , Neoplasias del Timo/inmunología , Neoplasias del Timo/patologíaRESUMEN
The promise of cancer immunotherapy is that it will not only eradicate primary tumors but will generate systemic antitumor immunity capable of destroying distant metastases. A major problem that must first be surmounted relates to the immune resistance of large tumors. Here we reveal that immune resistance can be overcome by combining immunotherapy with a concerted attack on the tumor vasculature. The functionally related antitumor drugs 5,6-dimethylxanthenone-4-acetic acid (DMXAA) and flavone acetic acid (FAA), which cause tumor vasculature collapse and tumor necrosis, were used to attack the tumor vasculature, whereas the T-cell costimulator B7.1 (CD80), which costimulates T-cell proliferation via the CD28 pathway, was used to stimulate antitumor immunity. The injection of cDNA (60-180 microg) encoding B7.1 into large EL-4 tumors (0.8 cm in diameter) established in C57BL/6 mice, followed 24 h later by i.p. administration of either DMXAA (25 mg/kg) or FAA (300 mg/kg), resulted in complete tumor eradication within 2-6 weeks. In contrast, monotherapies were ineffective. Both vascular attack and B7.1 immunotherapy led to up-regulation of heat shock protein 70 on stressed and dying tumor cells, potentially augmenting immunotherapy. Remarkably, large tumors took on the appearance of a wound that rapidly ameliorated, leaving perfectly healed skin. Combined therapy was mediated by CD8+ T cells and natural killer cells, accompanied by heightened and prolonged antitumor cytolytic activity (P < 0.001), and by a marked increase in tumor cell apoptosis. Cured animals completely rejected a challenge of 1 x 10(7) parental EL-4 tumor cells but not a challenge of 1 x 10(4) Lewis lung carcinoma cells, demonstrating that antitumor immunity was tumor specific. Adoptive transfer of 2 x 10(8) splenocytes from treated mice into recipients bearing established (0.8 cm in diameter) tumors resulted in rapid and complete tumor rejection within 3 weeks. Although DMXAA and B7.1 monotherapies are complicated by a narrow range of effective doses, combined therapy was less dosage dependent. Thus, a broad range of amounts of B7.1 cDNA were effective in combination with 25 mg/kg DMXAA. In contrast, DMXAA, which has a very narrow range of high active doses, was effective at a low dose (18 mg/kg) when administered with a large amount (180 microg) of B7.1 cDNA. Importantly, combinational therapy generated heightened antitumor immunity, such that gene transfer of B7.1 into one tumor, followed by systemic DMXAA treatment, led to the complete rejection of multiple untreated tumor nodules established in the opposing flank. These findings have important implications for the future direction and utility of cancer immunotherapies aimed at harnessing patients' immune responses to their own tumors.
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Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Antígeno B7-1/inmunología , Inmunoterapia/métodos , Neovascularización Patológica/terapia , Xantonas , Animales , Antígeno B7-1/genética , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Terapia Combinada , Femenino , Flavonoides/administración & dosificación , Dosificación de Gen , Terapia Genética , Vectores Genéticos/genética , Células Asesinas Naturales/inmunología , Subgrupos Linfocitarios/inmunología , Linfoma/inmunología , Linfoma/patología , Linfoma/terapia , Ratones , Ratones Endogámicos C57BL , Linfocitos T Citotóxicos/inmunología , Neoplasias del Timo/irrigación sanguínea , Neoplasias del Timo/inmunología , Neoplasias del Timo/patología , Neoplasias del Timo/terapia , Xantenos/administración & dosificaciónRESUMEN
In the study, we investigate whether the expressions of heat shock protein (hsp)60 (a potential autoantigen) and the stress-inducible form of cytoprotector hsp70 are correlated with the development of atherosclerotic lesions in the aortic tree of apolipoprotein E-deficient (apoE(-/-)) mice. The apoE(-/-) mouse model is advantageous because the stress-inducible form of hsp70 is not constitutively expressed in mice, unlike primates; hence, tissues under stress can be clearly defined. Both mammalian hsps were detected newly expressed (before mononuclear cell infiltration) on aortic valves and endothelia at lesion-prone sites of 3-week-old apoE(-/-) mice. In 8- and 20-week-old mice, they were strongly and heterogeneously expressed in early to advanced fibrofatty plaques, with levels correlating with lesion severity. Expression was markedly downregulated in advanced collagenous, acellular, calcified plaques of 40- and 69-week-old mice and was absent in control aortas of normocholesterolemic wild-type (apoE(+/+)) mice. Western blot analysis of tissue homogenates confirmed the temporal expression of the hsps. Double immunostaining revealed that both hsps were expressed by lesional endothelial cells, macrophages, smooth muscle cells, and CD3(+) T lymphocytes. This study provides evidence that hsp60 and hsp70 are temporally expressed on all major cell types in lesion-prone sites during atherogenesis, suggesting that few cells escape the toxic environment of the atherosclerotic plaque.
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Apolipoproteínas E/deficiencia , Arterias/metabolismo , Arterias/patología , Arteriosclerosis/metabolismo , Arteriosclerosis/patología , Chaperonina 60/metabolismo , Proteínas HSP70 de Choque Térmico/metabolismo , Animales , Aorta/metabolismo , Aorta/patología , Western Blotting , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Regulación hacia Abajo , Inmunohistoquímica , Macrófagos/metabolismo , Ratones , Ratones Mutantes , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patología , Linfocitos T/metabolismo , Regulación hacia ArribaRESUMEN
Leukocytes infiltrate the pancreatic islets of nonobese diabetic mice, causing beta-cell destruction and autoimmune Type I diabetes. Here, we completely blocked adoptive transfer of diabetes and reduced spontaneous disease incidence from 71% to 17% by simultaneously administering a combination of antibodies directed against alpha4, beta2, and beta7 integrins and their ligands VCAM-1, MAdCAM-1, and ICAM-1 for 52 and 28 days, respectively. CD4 and CD8 T cells and macrophages were excluded from islets and remained entrapped in a peri-islet location as inactive exiles, no longer expressing normal levels of interferon-gamma, interleukin-4, and iNOS. Only IL-10 expression was retained, which could aid immunosuppression. Infiltrating leukocytes retained a peri-islet location, even 215 days following suspension of antibody treatment, potentially forming a barrier to the entry of active, autoantigen-reactive T cells. Combination treatment was effective against spontaneous disease when administered from 7 days of age but ineffective when initiated late in the prediabetic period (day 40 or 70). Nevertheless, anti-alpha4 subunit mAb monotherapy alone was very effective, reducing insulitis to levels similar to those obtained with combinational antibody treatment, suggesting that alpha4 integrins are major receptors contributing to leukocyte infiltration. Treatment with anti-alpha4 integrin antibody retained some therapeutic benefit when administered from days 7, 40, or 70 of age. The results have implications for the treatment of diabetes and provide a unique insight into the fate of disease-forming leukocytes following anti-CAM therapy.
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Anticuerpos Monoclonales/uso terapéutico , Moléculas de Adhesión Celular/antagonistas & inhibidores , Quimiotaxis de Leucocito/efectos de los fármacos , Diabetes Mellitus Tipo 1/terapia , Integrinas/antagonistas & inhibidores , Islotes Pancreáticos , Traslado Adoptivo , Factores de Edad , Animales , Antígenos CD/inmunología , Adhesión Celular/efectos de los fármacos , Moléculas de Adhesión Celular/inmunología , Diabetes Mellitus Tipo 1/etiología , Diabetes Mellitus Tipo 1/patología , Femenino , Inflamación/patología , Inflamación/prevención & control , Integrina alfa4 , Integrinas/inmunología , Islotes Pancreáticos/patología , Leucocitos/efectos de los fármacos , Leucocitos/fisiología , Ratones , Ratones Endogámicos NOD , Bazo/citología , Factores de TiempoRESUMEN
BACKGROUND AND PURPOSE: The aim of this study was to determine the potency and molecular mechanism of action of YM155, a first-in-class survivin inhibitor that is currently under phase I/II clinical investigations, in various drug-resistant breast cancers including the oestrogen receptor positive (ER(+) ) tamoxifen-resistant breast cancer and the caspase-3-deficient breast cancer. EXPERIMENTAL APPROACH: The potency of YM155 in SK-BR-3, MDA-MB-231, MCF7 and its tamoxifen-resistant sublines, TamR6, TamR7, TamR8, TamC3 and TamC6, were determined by MTT assay. Western blot analysis, flow cytometric analysis, reverse transcription-PCR, fluorescent microscopy and comet assay were used to determine the molecular mechanism of action of YM155 in different breast cancer cell lines. KEY RESULTS: YM155 was equally potent towards the parental ER(+) /caspase-3-deficient MCF7 breast cancer cells and its tamoxifen-resistant sublines in vitro. The ER(-) /HER2(+) SK-BR-3 breast cancer cells and the triple-negative/caspase-3-expressing metastatic aggressive MDA-MB-231 breast cancer cells were also sensitive to YM155 with IC50 values in the low nanomolar range. Targeting survivin by YM155 modulated autophagy, induced autophagy-dependent caspase-7 activation and autophagy-dependent DNA damage in breast cancer cells. Interestingly, YM155 also induced XIAP degradation and the degradation of XIAP might play an important role in YM155-induced autophagy in breast cancer cells. CONCLUSIONS AND IMPLICATIONS: YM155 is a potent survivin inhibitor that has potential for the management of various breast cancer subtypes regardless of the expression of ER, HER2 and caspase-3. Importantly, this study provides new insights into YM155's molecular mechanism of action and therapeutic potential in the treatment of tamoxifen-resistant breast cancer.
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Antineoplásicos/farmacología , Neoplasias de la Mama/metabolismo , Daño del ADN , Imidazoles/farmacología , Proteínas Inhibidoras de la Apoptosis/metabolismo , Naftoquinonas/farmacología , Proteína Inhibidora de la Apoptosis Ligada a X/metabolismo , Autofagia/efectos de los fármacos , Caspasa 3/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Regulación hacia Abajo/efectos de los fármacos , Humanos , Proteínas Inhibidoras de la Apoptosis/genética , L-Lactato Deshidrogenasa/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , ARN Interferente Pequeño/genética , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/metabolismo , SurvivinRESUMEN
Heat shock proteins (hsps) chaperone cytosolic peptides, forming complexes that stimulate antitumor immunity. Hsps facilitate signal 1 in the two-signal model of T-cell costimulation, whereas cell adhesion molecules such as B7.1 provide secondary (signal 2) costimulatory signals. B7.1 gene transfer into tumors in situ has been shown to eradicate small (<0.3 cm in diameter) tumors in mice, and induce systemic antitumor immunity, but is ineffective against larger tumors. We examine whether mammalian hsps, as facilitators of T-cell costimulation, also exhibit this ability, and whether simultaneously stimulating both signal 1 (hsp-facilitated antigen presentation) and signal 2 (B7.1-mediated costimulation) enhances antitumor immunity compared to that achieved with either monotherapy. Prophylactic vaccination of mice with an hsp preparation from an EL-4 lymphoma weakly retarded tumor growth, to the same extent as that achieved with a single EL-4-derived peptide (AQHPNAELL), previously shown to induce antitumor immunity establishing that a preparation of EL-4 hsp-peptide complexes has antitumor activity. Here we show that injection of rat hsp70.1 into mouse tumors in situ causes the complete eradication of tumors, and generates potent systemic antitumor immunity mediated by CD4+ and CD8+ T cells. Unexpectedly, simultaneous gene transfer of hsp70.1 and B7.1 compromised the efficacy of hsp-mediated tumor rejection--a problem which could be partially overcome by the timed delivery of hsp70.1 and B7.1. Thus, gene transfer of hsp70 into tumors can be employed to generate potent systemic antitumor immunity, but further consideration is required if this approach is to be successfully combined with immunotherapies employing other T-cell costimulators.
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Antígeno B7-1/genética , Citotoxicidad Inmunológica/genética , Proteínas HSP70 de Choque Térmico/genética , Inmunoterapia , Proteínas Protozoarias/genética , Animales , Presentación de Antígeno/genética , Presentación de Antígeno/inmunología , Antígeno B7-1/inmunología , Terapia Genética , Proteínas HSP70 de Choque Térmico/inmunología , Ratones , Ratones Endogámicos C57BL , Proteínas Protozoarias/inmunología , Ratas , Linfocitos T/inmunología , Transfección , Células Tumorales CultivadasRESUMEN
Tumors must develop an adequate vascular network to meet their increasing demands for nutrition and oxygen. Angiostatin, a multiple kringle (1-4)-containing fragment of plasminogen, is an effective natural inhibitor of tumor angiogenesis. Here we show that gene transfer of angiostatin into small (0.1 cm in diameter) solid EL-4 lymphomas established in syngeneic C57BL/6 mice led to reduced tumor angiogenesis and weak inhibition of tumor growth. In contrast, when angiostatin gene therapy was preceded by in situ gene transfer of the T-cell costimulator B7.1, large (0.4 cm in diameter) tumors were rapidly and completely eradicated, whereas B7.1 and angiostatin monotherapies were ineffective. Combined gene transfer of B7.1 and angiostatin generated potent systemic antitumor immunity that was effective in eradicating a systemic challenge of 10(7) EL-4 cells. Gene transfer of angiostatin expression plasmids led to overexpression of angiostatin in tumors, increased apoptosis of tumor cells, and decreased density of tumor blood vessels, which may allow the immune system to overcome tumor immune resistance. The latter effects were not the result of a decrease in vascular endothelial growth factor expression, as tumoral vascular endothelial growth factor expression increased slightly after angiostatin gene transfer, presumably in response to increasing hypoxia. These results suggest that combining immunogene therapy with a vascular attack by angiostatin is a particularly effective approach for eliciting antitumor immunity.
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Antígeno B7-1/genética , Factores de Crecimiento Endotelial/metabolismo , Terapia Genética/métodos , Inmunoterapia/métodos , Linfocinas/metabolismo , Fragmentos de Péptidos/genética , Plasminógeno/genética , Neoplasias del Timo/terapia , Angiostatinas , Animales , Western Blotting , Terapia Combinada , Cartilla de ADN/química , Técnicas de Transferencia de Gen , Técnicas para Inmunoenzimas , Masculino , Ratones , Ratones Endogámicos C57BL , Neovascularización Patológica/prevención & control , Fragmentos de Péptidos/metabolismo , Plasminógeno/metabolismo , Reacción en Cadena de la Polimerasa/métodos , Linfocitos T/inmunología , Neoplasias del Timo/irrigación sanguínea , Neoplasias del Timo/metabolismo , Células Tumorales Cultivadas , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial VascularRESUMEN
The use of bacteria in the regression of tumors has long been known. Various approaches for using bacteria in cancer therapy include the use of bacteria as sensitizing agents for chemotherapy, as delivery agents for cancer drugs and as agents for gene therapy. The tumor regression stimulated by infecting microorganisms has been attributed to activation of the immune system of the host. However, recent studies indicate that when tumor-harboring mice with defective immune systems are infected with certain microorganisms, the regression of the tumor is still observed, suggesting that there are other host factors contributing to the microbial associated regression of tumors. Since the use of live or attenuated bacteria for tumor regression has associated toxic effects, studies are in progress to identify a pure microbial metabolite or any component of the microbial cell that might have anti-cancer activity. It has now been demonstrated that a redox protein from Pseudomonas aeruginosa, a cupredoxin, can enter into human cancer cells and trigger the apoptotic cell death. In vivo, this cupredoxin can lead to the regression of tumor growth in immunodeficient mice harboring xenografted melanomas and breast cancer tumors without inducing significant toxic effects, suggesting that it has potential anti-cancer activity. This bacterial protein interacts with p53 and modulates mammalian cellular activity. Hence, it could potentially be used as an anti-cancer agent for solid tumors and has translational value in tumor-targeted or in combinational-biochemotherapy strategies for cancer treatments. Here, we focus on diverse approaches to cancer biotherapy, including bacteriolytic and bacterially-derived anti-cancer agents with an emphasis on their mechanism of action and therapeutic potential.
Asunto(s)
Apoptosis , Bacterias/inmunología , Vacunas contra el Cáncer/inmunología , Neoplasias/irrigación sanguínea , Neoplasias/terapia , Neovascularización Patológica , Animales , Bacterias/genética , Vacunas contra el Cáncer/genética , Vectores Genéticos/genética , Humanos , Neoplasias/inmunología , Neoplasias/patologíaRESUMEN
A role for alpha4 integrins in different forms of the multiple sclerosis-like disease experimental autoimmune encephalomyelitis (EAE) has been demonstrated, but the individual contributions of alpha4beta1, alpha4beta7, and the related alphaEbeta7 integrin have not been determined. The P7 integrins alpha4beta7 and alphaEbeta7 play a central role in chronic inflammation, mediating the trafficking, entry, and/or adhesion of lymphocytes in the inflamed pancreas and gut, and their ligands MAdCAM-1, VCAM-1 and E-cadherin are expressed on brain endothelial cells and/or on microvessels in the inflamed central nervous system. Here, we show that an antibody directed against the beta7 subunit greatly attenuates a non-remitting form of EAE, induced by adoptive transfer of myelin oligodendrocyte peptide (MOG35-55)-stimulated T cells. Combinational treatment with both anti-beta7 and alpha4 integrin subunit antibodies led to more rapid and complete remission than that obtained with anti-alpha4 antibody alone, potentially implicating a role for alphaEbeta7 in disease progression. Remission correlated with the down-regulation of the vascular addressins VCAM-1. MAdCAM-1, and ICAM-1 on cerebral blood vessels. Attenuated forms of disease were induced by adoptive transfer of either wild-type encephalitogenic T cells to beta7-deficient gene knockout mice, or of beta7-/-encephalitogenic T cells to wild-type recipients. The former finding indicates that beta7 + ve recruited cells contribute to disease progression. Thus alpha4beta1, alpha4beta7, and alphaEbeta7 integrins may all play a contributory role in the progression of chronic forms of demyelinating disease, and together with their ligands could represent potential targets for improved treatment of some forms of multiple sclerosis.
Asunto(s)
Encefalomielitis Autoinmune Experimental/inmunología , Encefalomielitis Autoinmune Experimental/metabolismo , Cadenas beta de Integrinas , Integrinas/metabolismo , Traslado Adoptivo , Animales , Anticuerpos Monoclonales/administración & dosificación , Antígenos CD/inmunología , Encéfalo/inmunología , Encéfalo/metabolismo , Encéfalo/patología , Células Cultivadas , Enfermedades Autoinmunes Desmielinizantes SNC/metabolismo , Sinergismo Farmacológico , Encefalomielitis Autoinmune Experimental/complicaciones , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Integrina alfa4 , Integrinas/antagonistas & inhibidores , Integrinas/genética , Integrinas/inmunología , Activación de Linfocitos/efectos de los fármacos , Linfocitos/citología , Linfocitos/efectos de los fármacos , Linfocitos/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas de la Mielina , Glicoproteína Asociada a Mielina/inmunología , Glicoproteína Asociada a Mielina/farmacología , Glicoproteína Mielina-Oligodendrócito , Parálisis/etiología , Parálisis/prevención & controlRESUMEN
Unidirectional fluxes of Na+, Cl- and 3-O-methyl-D-glucose (3-MG) were measured in vitro across Campylobacter jejuni live culture-infected and control rat ileal short-circuited tissues by the Ussing Chamber technique. Net secretion of Na+ and enhanced secretion of Cl- ions was observed in the infected animals (P < 0.001, n = 6) as compared to the net absorption of Na+ and marginal secretion of Cl- ions in the control animals. There was a significant decrease in the mucosal-to-serosal fluxes of 3-MG in C. jejuni-infected rat ileum. The specific Na+,K(+)-ATPase activity when measured biochemically in the membrane-rich fraction of enterocytes was found to be significantly lower (58%) in the infected group as compared to the control group (P < 0.001). Our results therefore suggest that infection with an enterotoxigenic C. jejuni inhibits the Na+,K(+)-ATPase activity in rat enterocytes. The impairment of Na+,K(+)-ATPase activity thus appears to induce a secondary change in Na+,Cl- and 3-MG transport in vitro in rat ileum.
Asunto(s)
Infecciones por Campylobacter/metabolismo , Campylobacter jejuni , Cloruros/metabolismo , Íleon/metabolismo , Metilglucósidos/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/antagonistas & inhibidores , Sodio/metabolismo , 3-O-Metilglucosa , Animales , Íleon/microbiología , Técnicas In Vitro , Transporte Iónico , Masculino , Ratas , Ratas WistarRESUMEN
Micro-enzyme-linked immunosorbent assay (Micro-ELISA) systems were developed and evaluated for the detection of circulating (free or immune-complexed) hydatid antigens in the sera of patients with hydatidosis, by employing monospecific antibodies to hydatid-specific antigens of 8-kDa and 116-kDa. Fifteen (75%) of 20 sera from patients with hydatidosis had both 8-kDa and 116-kDa antigens freely circulating in their sera while three and two samples, respectively, had only 8-kDa or 116-kDa antigen. All the surgically confirmed cases of hydatidosis had detectable levels of both 8-kDa and 116-kDa circulating immune complexes in glycine HCl-treated sera. However, none of the sera from control subjects (patients with cysticercosis, ascariasis, ancylostomiasis, hymenolepiasis, amoebic liver abscess or viral hepatitis) had any detectable level of either type of circulating specific antigen. These results suggest that the demonstration of either 8- or 116-kDa antigen(s) in free or immune-complex form could confirm the diagnosis of hydatidosis.
Asunto(s)
Complejo Antígeno-Anticuerpo/sangre , Antígenos Helmínticos/sangre , Equinococosis/diagnóstico , Equinococosis/inmunología , Ensayo de Inmunoadsorción Enzimática , Adulto , Anticuerpos Antihelmínticos/sangre , Humanos , Sensibilidad y EspecificidadRESUMEN
Hydatid fluids from sheep, goat, pig and man, after resolution by sodium dodecyl sulphate-polyacrylamide gel electrophoresis under reducing conditions, revealed at least 15 discrete polypeptide bands of 8-116 Kda. By ELISA, sera from all 20 cases of hydatidosis showed anti-hydatid antibody, but so did 11 (73%) of 15 sera samples from cysticercosis patients, eight (67%) of 12 sera from patients with other parasitic infections (amoebic liver abscess or hymenolepiasis) and one (4%) of 25 sera from healthy controls. Antibody to cysticercus antigen was found in 14 (93%) of 15 sera from cysticercosis patients, 17 (85%) of 20 sera from hydatid patients, six (50%) of 12 sera from patients with other parasitic infections and one (4%) of 25 sera from healthy controls. Sera from 17 (85%) of 20 hydatid patients, 11 (73%) of 15 cysticercosis patients and five (42%) of 12 patients with other parasitic infections had antibodies to both hydatid and cysticercus antigens. Sera from 20 surgically confirmed cases of hydatidosis reacted with 12 polypeptides of 8-116 Kda in Western immunoblot with hydatid antigens. Polypeptides of 16, 24, 38, 45 and 58 Kda were recognised by all hydatidosis sera but also by many sera from patients with other infections. However, polypeptides of 8 and 116 Kda were recognised by all hydatidosis sera but not by any sera from patients with cysticercosis, other parasitic infections or viral hepatitis, or from healthy controls. Thus, recognition of 8- and 116-Kda hydatid antigens by a patient's serum appears to be a specific test confirming a clinical diagnosis in an individual case of hydatidosis.
Asunto(s)
Anticuerpos Antihelmínticos/sangre , Equinococosis/inmunología , Echinococcus/inmunología , Animales , Western Blotting , Reacciones Cruzadas , Cisticercosis/inmunología , Cysticercus/inmunología , Equinococosis/diagnóstico , Equinococosis/veterinaria , Ensayo de Inmunoadsorción Enzimática , Cabras , Hepatitis B/inmunología , Humanos , Himenolepiasis/sangre , Absceso Hepático Amebiano/sangre , Sensibilidad y Especificidad , Ovinos , PorcinosRESUMEN
A hydatid specific antigen of 8 kDa molecular mass was affinity-purified from crude hydatid cyst fluid. Some of the epitopes recognised by antibodies in the sera from sheep with hydatidosis were periodate-sensitive. The purified 8 kDa antigen was observed to be a thermo-stable glycoprotein in its immunochemical characteristics. By immunofluorescence on acetone-fixed protoscolices anti-8 kDa monospecific IgG antibodies indicated the existence of the 8 kDa molecule on the hooklets of protoscolices. The purified antigen was used in an enzyme-linked immunosorbent assay for the detection of specific antibodies in sera from sheep hydatiodosis. Eighteen (90%) of 20 sera from sheep hydatidosis had antibodies to purified 8 kDa antigen while none of the sera from other parasitic infections or uninfected animals had any detectable levels of antibodies to 8 kDa antigen. Thus, the data on localization and recognition of hydatid specific 8 kDa molecule suggested that this may be one of the major molecules for specific immunodiagnosis and for modulating the hydatid disease process in infected hosts.