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1.
Vet Res ; 51(1): 59, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32357948

RESUMEN

We report the generation, characterization and epitope mapping of a panel of 26 monoclonal antibodies (MAbs) against the VP1 capsid protein of feline calicivirus (FCV). Two close but distinct linear epitopes were identified at the capsid outermost surface (P2 subdomain) of VP1, within the E5'HVR antigenic hypervariable region: one spanning amino acids 431-435 (PAGDY), highly conserved and recognized by non-neutralizing MAbs; and a second epitope spanning amino acids 445-451 (ITTANQY), highly variable and recognized by neutralizing MAbs. These antibodies might be valuable for diagnostic applications, as well as for further research in different aspects of the biology of FCV.


Asunto(s)
Anticuerpos Monoclonales/metabolismo , Anticuerpos Neutralizantes/metabolismo , Anticuerpos Antivirales/metabolismo , Calicivirus Felino/química , Cápside/química , Epítopos/química
2.
Vet Res ; 46: 106, 2015 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-26403184

RESUMEN

In 2010 a new Lagovirus related to rabbit haemorrhagic disease virus (RHDV) emerged in France and has since rapidly spread throughout domestic and wild rabbit populations of several European countries. The new virus, termed RHDV2, exhibits distinctive genetic, antigenic and pathogenic features. Notably, RHDV2 kills rabbits previously vaccinated with RHDV vaccines. Here we report for the first time the generation and characterization of RHDV2-specific virus-like particles (VLPs). Our results further confirmed the differential antigenic properties exhibited by RHDV and RHDV2, highlighting the need of using RHDV2-specific diagnostic assays to monitor the spread of this new virus.


Asunto(s)
Antígenos Virales/inmunología , Infecciones por Caliciviridae/veterinaria , Lagovirus/inmunología , Conejos , Animales , Infecciones por Caliciviridae/inmunología , Infecciones por Caliciviridae/virología , Virus de la Enfermedad Hemorrágica del Conejo/genética , Virus de la Enfermedad Hemorrágica del Conejo/inmunología , Lagovirus/genética , Filogenia , Análisis de Secuencia de ADN/veterinaria
3.
J Virol ; 86(12): 6470-80, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22491457

RESUMEN

Viruses need only one or a few structural capsid proteins to build an infectious particle. This is possible through the extensive use of symmetry and the conformational polymorphism of the structural proteins. Using virus-like particles (VLP) from rabbit hemorrhagic disease virus (RHDV) as a model, we addressed the basis of calicivirus capsid assembly and their application in vaccine design. The RHDV capsid is based on a T=3 lattice containing 180 identical subunits (VP1). We determined the structure of RHDV VLP to 8.0-Å resolution by three-dimensional cryoelectron microscopy; in addition, we used San Miguel sea lion virus (SMSV) and feline calicivirus (FCV) capsid subunit structures to establish the backbone structure of VP1 by homology modeling and flexible docking analysis. Based on the three-domain VP1 model, several insertion mutants were designed to validate the VP1 pseudoatomic model, and foreign epitopes were placed at the N- or C-terminal end, as well as in an exposed loop on the capsid surface. We selected a set of T and B cell epitopes of various lengths derived from viral and eukaryotic origins. Structural analysis of these chimeric capsids further validates the VP1 model to design new chimeras. Whereas most insertions are well tolerated, VP1 with an FCV capsid protein-neutralizing epitope at the N terminus assembled into mixtures of T=3 and larger T=4 capsids. The calicivirus capsid protein, and perhaps that of many other viruses, thus can encode polymorphism modulators that are not anticipated from the plane sequence, with important implications for understanding virus assembly and evolution.


Asunto(s)
Proteínas de la Cápside/metabolismo , Cápside/metabolismo , Virus de la Enfermedad Hemorrágica del Conejo/fisiología , Ensamble de Virus , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Animales , Cápside/química , Proteínas de la Cápside/química , Proteínas de la Cápside/genética , Línea Celular , Epítopos/genética , Epítopos/metabolismo , Virus de la Enfermedad Hemorrágica del Conejo/química , Virus de la Enfermedad Hemorrágica del Conejo/genética , Imagenología Tridimensional , Datos de Secuencia Molecular , Mariposas Nocturnas , Mutagénesis Insercional , Alineación de Secuencia
4.
Front Immunol ; 13: 888427, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36159783

RESUMEN

Purpose: Janus kinase-1 (JAK1) tyrosine kinase mediates signaling from multiple cytokine receptors, including interferon alpha/beta and gamma (IFN-α/ß and IFN-γ), which are important for viral and mycobacterial protection respectively. We previously reported autosomal recessive (AR) hypomorphic JAK1 mutations in a patient with recurrent atypical mycobacterial infections and relatively minor viral infections. This study tests the impact of partial JAK1 deficiency on cellular responses to IFNs and pathogen control. Methods: We investigated the role of partial JAK1 deficiency using patient cells and cell models generated with lentiviral vectors expressing shRNA. Results: Partial JAK1 deficiency impairs IFN-γ-dependent responses in multiple cell types including THP-1 macrophages, Epstein-Barr Virus (EBV)-transformed B cells and primary dermal fibroblasts. In THP-1 myeloid cells, partial JAK1 deficiency reduced phagosome acidification and apoptosis and resulted in defective control of mycobacterial infection with enhanced intracellular survival. Although both EBV-B cells and primary dermal fibroblasts with partial JAK1 deficiency demonstrate reduced IFN-α responses, control of viral infection was impaired only in patient EBV-B cells and surprisingly intact in patient primary dermal fibroblasts. Conclusion: Our data suggests that partial JAK1 deficiency predominantly affects susceptibility to mycobacterial infection through impact on the IFN-γ responsive pathway in myeloid cells. Susceptibility to viral infections as a result of reduced IFN-α responses is variable depending on cell type. Description of additional patients with inherited JAK1 deficiency will further clarify the spectrum of bacterial and viral susceptibility in this condition. Our results have broader relevance for anticipating infectious complications from the increasing use of selective JAK1 inhibitors.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Infecciones por Mycobacterium , Mycobacterium , Herpesvirus Humano 4/genética , Humanos , Interferón-alfa/farmacología , Interferón beta , Interferón gamma/genética , Janus Quinasa 1/genética , Mycobacterium/genética , Infecciones por Mycobacterium/genética , ARN Interferente Pequeño , Receptores de Citocinas
5.
Glycobiology ; 21(10): 1349-61, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21632870

RESUMEN

In this work, we analyzed at high resolution the sugar-binding mode of the recombinant N-terminal ricin-B domain of the hemolytic protein LSLa (LSL(150)) from the mushroom Laetiporus sulphureus and also provide functional in vitro evidence suggesting that, together with its putative receptor-binding role, this module may also increase the solubility of its membrane pore-forming partner. We first demonstrate that recombinant LSL(150) behaves as an autonomous folding unit and an active lectin. We have determined its crystal structure at 1.47 Å resolution and also that of the [LSL(150):(lactose)ß, γ)] binary complex at 1.67 Å resolution. This complex reveals two lactose molecules bound to the ß and γ sites of LSL(150), respectively. Isothermal titration calorimetry indicates that LSL(150) binds two lactoses in solution with highly different affinities. Also, we test the working hypothesis that LSL(150) exhibits in vivo properties typical of solubility tags. With this aim, we have fused an engineered version of LSL(150) (LSL(t)) to the N-terminal end of various recombinant proteins. All the designed LSL(150)-tagged fusion proteins were successfully produced at high yield, and furthermore, the target proteins were purified by a straightforward affinity procedure on agarose-based matrices due to the excellent properties of LSL(150) as an affinity tag. An optimized protocol for target protein purification was devised, which involved removal of the LSL(150) tag through in-column cleavage of the fusion proteins with His(6)-tagged TEV endoprotease. These results permitted to set up a novel, lectin-based system for production and purification of recombinant proteins in E. coli cells with attractive biotechnological applications.


Asunto(s)
Coriolaceae/metabolismo , Lectinas/química , Carbohidratos/química , Cristalografía por Rayos X , Lactosa/química , Lactosa/metabolismo , Lectinas/genética , Lectinas/metabolismo , Pliegue de Proteína , Estructura Terciaria de Proteína , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo
6.
Proteins ; 78(7): 1662-76, 2010 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-20112419

RESUMEN

p-Coumaric acid decarboxylases (PDCs) catalyze the nonoxidative decarboxylation of hydroxycinnamic acids to generate the corresponding vinyl derivatives. Despite the biotechnological relevance of PDCs in food industry, their catalytic mechanism remains largely unknown. Here, we report insights into the structural basis of catalysis for the homodimeric PDC from Lactobacillus plantarum (LpPDC). The global fold of LpPDC is based on a flattened beta-barrel surrounding an internal cavity. Crystallographic and functional analyses of single-point mutants of residues located within this cavity have permitted identifying a potential substrate-binding pocket and also to provide structural evidences for rearrangements of surface loops so that they can modulate the accessibility to the active site. Finally, combination of the structural and functional data with in silico results enables us to propose a two-step catalytic mechanism for decarboxylation of p-coumaric acid by PDCs where Glu71 is involved in proton transfer, and Tyr18 and Tyr20 are involved in the proper substrate orientation and in the release of the CO(2) product.


Asunto(s)
Carboxiliasas/química , Lactobacillus plantarum/enzimología , Algoritmos , Secuencia de Aminoácidos , Carboxiliasas/genética , Carboxiliasas/metabolismo , Catálisis , Dominio Catalítico , Cristalografía por Rayos X , Enlace de Hidrógeno , Modelos Moleculares , Simulación de Dinámica Molecular , Datos de Secuencia Molecular , Mutación Puntual , Conformación Proteica , Pliegue de Proteína , Alineación de Secuencia
7.
Artículo en Inglés | MEDLINE | ID: mdl-20516596

RESUMEN

As part of the life cycle of the pneumococcal phage Cp-7, the endolysin Cpl-7 cleaves the glycosidic beta1,4 bonds between N-acetylmuramic acid and N-acetylglucosamine in the pneumococcal cell wall, resulting in bacterial lysis. Recombinant Cpl-7 was overexpressed in Escherichia coli, purified and crystallized using the vapour-diffusion method at 291 K. Diffraction-quality tetragonal crystals of the catalytic module of Cpl-7 were obtained from a mixture of PEG 3350 and sodium formate. The crystals belonged to space group I422, with unit-cell parameters a = 127.93, b = 127.93, c = 82.07 A. Diffraction data sets were collected to 2.4 A resolution using a rotating-anode generator.


Asunto(s)
Bacteriófagos/química , Biocatálisis , Endopeptidasas/química , Streptococcus pneumoniae/virología , Bacteriófagos/metabolismo , Cristalización , Cristalografía por Rayos X , Endopeptidasas/metabolismo
8.
J Appl Toxicol ; 30(6): 497-512, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20583319

RESUMEN

Ion channels play essential roles in human physiology and toxicology. Cardiac contraction, neural transmission, temperature sensing, insulin release, regulation of apoptosis, cellular pH and oxidative stress, as well as detection of active compounds from chilli, are some of the processes in which ion channels have an important role. Regulation of ion channels by several chemicals including those found in air, water and soil represents an interesting potential link between environmental pollution and human diseases; for instance, de novo expression of ion channels in response to exposure to carcinogens is being considered as a potential tool for cancer diagnosis and therapy. Non-specific binding of several drugs to ion channels is responsible for a huge number of undesirable side-effects, and testing guidelines for several drugs now require ion channel screening for pharmaceutical safety. Animal toxins targeting human ion channels have serious effects on the population and have also provided a remarkable tool to study the molecular structure and function of ion channels. In this review, we will summarize the participation of ion channels in biological processes extensively used in toxicological studies, including cardiac function, apoptosis and cell proliferation. Major findings on the adverse effects of drugs on ion channels as well as the regulation of these proteins by different chemicals, including some pesticides, are also reviewed. Association of ion channels and toxicology in several biological processes strongly suggests these proteins to be excellent candidates to follow the toxic effects of xenobiotics, and as potential early indicators of life-threatening situations including chronic degenerative diseases.


Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Contaminantes Ambientales/toxicidad , Canales Iónicos , Toxicología/métodos , Toxinas Biológicas/toxicidad , Animales , Apoptosis , Canales de Calcio/biosíntesis , Canales de Calcio/metabolismo , Canales de Calcio/fisiología , Canales de Cloruro/biosíntesis , Canales de Cloruro/metabolismo , Canales de Cloruro/fisiología , Humanos , Canales Iónicos/biosíntesis , Canales Iónicos/metabolismo , Canales Iónicos/fisiología , Neoplasias/inducido químicamente , Neoplasias/metabolismo , Neoplasias/patología , Canales de Potasio/biosíntesis , Canales de Potasio/metabolismo , Canales de Potasio/fisiología , Unión Proteica , Canales de Sodio/biosíntesis , Canales de Sodio/metabolismo , Canales de Sodio/fisiología
9.
Front Pharmacol ; 11: 152, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32210800

RESUMEN

Many ion channels are involved in tumor development, promoting cancer cell proliferation, migration, invasion, and survival. Accordingly, some of them have been suggested as tumor markers and novel targets for cancer therapy. Some sex steroid hormones (SSH), including estrogens and androgens, favor cancer progression. Meanwhile, other steroid hormones like vitamin D may have anticancer properties. SSH and vitamin D modulate the expression of a number of ion channels in cancer cells from hormone-sensitive tissues, including breast, ovary, prostate, and cervix. Moreover, rapid effects of SSH may be mediated by their direct action on membrane ion channels. Here, we reviewed the SSH and vitamin D regulation of ion channels involved in cancer, and analyzed the potential molecular pathways implicated. In addition, we described the potential clinical use of ion channels in cancer diagnosis and therapy, taking advantage of their regulation by SSH and vitamin D. Since SSH are considered risk factors for different types of cancer, and ion channels play important roles in tumor progression, the regulation of ion channels by SSH and vitamin D may represent a potential opportunity for early cancer diagnosis and therapeutic approaches in SSH and vitamin D sensitive tumors.

10.
J Clin Microbiol ; 46(12): 3971-9, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18842943

RESUMEN

Noroviruses (NoVs) are responsible for the majority of gastroenteritis outbreaks in humans. Recently, NoV strains which are genetically closely related to human genogroup II (GII) NoVs have been detected in fecal specimens from swine. These findings have raised concern about the possible role of pigs as reservoirs for NoVs that could infect humans. To better understand the epidemiology of swine NoVs in both the swine and the human populations, rapid immunoassays are needed. In this study, baculovirus recombinants were generated to express the capsid gene of a swine NoV GII genotype 11 (GII.11) strain which self-assembled into virus-like particles (VLPs). Subsequently, the purified VLPs were used to evoke monoclonal antibodies (MAbs) in mice. A panel of eight promising MAbs was obtained and evaluated for their ability to bind to heterologous VLPs, denaturated antigens, and truncated capsid proteins. The MAbs could be classified into two groups: two MAbs that recognized linear epitopes located at the amino-terminal half (shell domain) of the swine NoV GII.11 VLPs and that cross-reacted with human GII.4 NoV VLPs. The other six MAbs bound to conformational epitopes and did not cross-react with the human GII.4 VLPs. To our knowledge, this is the first report on the characterization of MAbs against swine NoVs. The swine NoV VLPs and the MAbs described here may be further used for the design of diagnostic reagents that could help increase our knowledge of the prevalence of NoV infections in pigs and the possible role of pigs as reservoirs for NoVs.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Anticuerpos Antivirales/inmunología , Infecciones por Caliciviridae/veterinaria , Proteínas de la Cápside/inmunología , Proteínas de la Cápside/metabolismo , Norovirus/inmunología , Virosomas/inmunología , Virosomas/metabolismo , Animales , Anticuerpos Monoclonales/aislamiento & purificación , Baculoviridae/genética , Infecciones por Caliciviridae/virología , Línea Celular , Reacciones Cruzadas , Epítopos/inmunología , Femenino , Humanos , Lepidópteros , Ratones , Ratones Endogámicos BALB C , Porcinos
11.
Artículo en Inglés | MEDLINE | ID: mdl-17620711

RESUMEN

The catabolic ornithine transcarbamylase (cOTC; EC 2.1.3.3) from the lactic acid bacteria Lactobacillus hilgardii is a key protein involved in the degradation of arginine during malolactic fermentation. cOTC containing an N-terminal His6 tag has been overexpressed in Escherichia coli, purified and crystallized under two different experimental conditions using the hanging-drop vapour-diffusion method. Crystals obtained from a solution containing 8% (w/v) PEG 4000, 75 mM sodium acetate pH 4.6 belong to the trigonal space group P321 and have unit-cell parameters a = b = 157.04, c = 79.28 A. Conversely, crystals grown in 20% (v/v) 2-methyl-2,4-pentanediol, 7.5% (w/v) PEG 4000, 100 mM HEPES pH 7.8 belong to the monoclinic space group C2 and have unit-cell parameters a = 80.06, b = 148.90, c = 91.67 A, beta = 100.25 degrees. Diffraction data were collected in-house to 3.00 and 2.91 A resolution for trigonal and monoclinic crystals, respectively. The estimated Matthews coefficient for the crystal forms were 2.36 and 2.24 A3 Da(-1), respectively, corresponding to 48% and 45% solvent content. In both cases, the results are consistent with the presence of three protein subunits in the asymmetric unit. The structure of cOTC has been determined by the molecular-replacement method using the atomic coordinates of cOTC from Pseudomonas aeruginosa (PDB code 1dxh) as the search model.


Asunto(s)
Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Regulación Enzimológica de la Expresión Génica , Lactobacillus/enzimología , Lactobacillus/genética , Ornitina Carbamoiltransferasa/química , Ornitina Carbamoiltransferasa/genética , Proteínas Bacterianas/biosíntesis , Proteínas Bacterianas/aislamiento & purificación , Cristalización , Cristalografía por Rayos X , Ornitina Carbamoiltransferasa/biosíntesis , Ornitina Carbamoiltransferasa/aislamiento & purificación
12.
Artículo en Inglés | MEDLINE | ID: mdl-17620712

RESUMEN

The salt-tolerance genes SOS3 (salt overly sensitive 3) and SOS2 (salt overly sensitive 2) regulatory domain of Arabidopsis thaliana were cloned into a polycistronic plasmid and the protein complex was expressed in Escherichia coli, allowing purification to homogeneity in three chromatographic steps. Crystals were grown using vapour-diffusion techniques. The crystals belonged to space group P2(1)2(1)2(1), with unit-cell parameters a = 44.14, b = 57.39, c = 141.90 A.


Asunto(s)
Proteínas de Arabidopsis/química , Arabidopsis/química , Arabidopsis/genética , Proteínas Serina-Treonina Quinasas/química , Arabidopsis/enzimología , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/aislamiento & purificación , Clonación Molecular , Cristalización , Cristalografía por Rayos X , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/aislamiento & purificación , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Proteínas Recombinantes/aislamiento & purificación
13.
Sci Rep ; 6: 31844, 2016 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-27549017

RESUMEN

Virus-like particles (VLPs), comprised of viral structural proteins devoid of genetic material, are tunable nanoparticles that can be chemically or genetically engineered, to be used as platforms for multimeric display of foreign antigens. Here, we report the engineering of chimeric VLPs, derived from rabbit hemorrhagic disease virus (RHDV) for presentation of foreign B-cell antigens to the immune system. The RHDV capsid comprises 180 copies of a single capsid subunit (VP60). To evaluate the ability of chimeric RHDV VLPs to elicit protective humoral responses against foreign antigens, we tested two B-cell epitopes: a novel neutralizing B-cell epitope, derived from feline calicivirus capsid protein, and a well characterized B-cell epitope from the extracellular domain of influenza A virus M2 protein (M2e). We generated sets of chimeric RHDV VLPs by insertion of the foreign B-cell epitopes at three different locations within VP60 protein (which involved different levels of surface accessibility) and in different copy numbers per site. The immunogenic potential of the chimeric VLPs was analyzed in the mouse model. The results presented here indicated that chimeric RHDV VLPs elicit potent protective humoral responses against displayed foreign B-cell epitopes, demonstrated by both, in vitro neutralization and in vivo protection against a lethal challenge.


Asunto(s)
Cápside/inmunología , Epítopos de Linfocito B/inmunología , Virus de la Enfermedad Hemorrágica del Conejo/inmunología , Inmunidad Humoral/inmunología , Animales , Linfocitos B/inmunología , Proteínas de la Cápside/genética , Proteínas de la Cápside/inmunología , Femenino , Virus de la Enfermedad Hemorrágica del Conejo/genética , Inmunización , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ingeniería de Proteínas/métodos , Conejos , Proteínas de la Matriz Viral/inmunología , Proteínas Estructurales Virales/genética , Proteínas Estructurales Virales/inmunología
14.
Nat Commun ; 7: 13992, 2016 12 23.
Artículo en Inglés | MEDLINE | ID: mdl-28008925

RESUMEN

Mutations in genes encoding components of the immune system cause primary immunodeficiencies. Here, we study a patient with recurrent atypical mycobacterial infection and early-onset metastatic bladder carcinoma. Exome sequencing identified two homozygous missense germline mutations, P733L and P832S, in the JAK1 protein that mediates signalling from multiple cytokine receptors. Cells from this patient exhibit reduced JAK1 and STAT phosphorylation following cytokine stimulations, reduced induction of expression of interferon-regulated genes and dysregulated cytokine production; which are indicative of signalling defects in multiple immune response pathways including Interferon-γ production. Reconstitution experiments in the JAK1-deficient cells demonstrate that the impaired JAK1 function is mainly attributable to the effect of the P733L mutation. Further analyses of the mutant protein reveal a phosphorylation-independent role of JAK1 in signal transduction. These findings clarify JAK1 signalling mechanisms and demonstrate a critical function of JAK1 in protection against mycobacterial infection and possibly the immunological surveillance of cancer.


Asunto(s)
Alelos , Janus Quinasa 1/genética , Mutación/genética , Infecciones por Mycobacterium/enzimología , Infecciones por Mycobacterium/genética , Secuencia de Aminoácidos , Secuencia de Bases , Células Sanguíneas/metabolismo , Niño , Preescolar , Citocinas/sangre , Susceptibilidad a Enfermedades , Femenino , Fibroblastos/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Interferón-alfa/farmacología , Interferón gamma/farmacología , Janus Quinasa 1/química , Masculino , Linaje , Fosforilación/efectos de los fármacos , Dominios Proteicos , Factores de Transcripción STAT/metabolismo , Transducción de Señal/genética , TYK2 Quinasa/metabolismo , Adulto Joven
15.
Haematologica ; 89(3): 273-80, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15020264

RESUMEN

BACKGROUND AND OBJECTIVES: Adhesion molecules on the surface of erythrocytes, leukocytes and platelets are involved in vascular occlusion in sickle cell anemia. Hydroxyurea treatment of sickle cell anemia patients leads to clinical improvement and reduces the incidence of vaso-occlusive episodes. It has been previously demonstrated that hydroxyurea treatment also reduces the expression of adhesion molecules on the surface of erythrocytes. Phosphatidylserine (PS) exposure on the surface of erythrocytes has been considered to be the main determinant of altered erythrocyte adhesion in sickle cell anemia. In this study we examine the expression of PS on the surface of erythrocytes and platelets of sickle cell anemia patients before and during treatment with hydroxyurea. DESIGN AND METHODS: Blood samples from 15 sickle cell anemia patients were analyzed before and during treatment with hydroxyurea. The profile of PS expression was examined by flow cytometry. RESULTS: Hydroxyurea was effective, as determined by the patients clinical improvement and increased hemoglobin (8.3 vs 9.1 g/dL, p< 0.005), F cells (15.9% vs 37.1%, p< 0.005) and mean corpuscular volume ( 82 fL vs 101 fL, p< 0.005). PS expression on the surface of erythrocytes and platelets decreased from 6.27% to 2.96% (p< 0.005) and from 13.5% to 4.7% (p< 0.005), respectively. INTERPRETATION AND CONCLUSIONS: Hydroxyurea treatment reduces PS expression on the surface of erythrocytes and platelets, thus contributing to the favorable effects of this therapy.


Asunto(s)
Anemia de Células Falciformes/tratamiento farmacológico , Antidrepanocíticos/farmacología , Plaquetas/efectos de los fármacos , Membrana Eritrocítica/efectos de los fármacos , Hidroxiurea/farmacología , Adolescente , Adulto , Anemia de Células Falciformes/sangre , Antidrepanocíticos/uso terapéutico , Plaquetas/citología , Moléculas de Adhesión Celular/metabolismo , Membrana Celular/efectos de los fármacos , Niño , Femenino , Humanos , Hidroxiurea/uso terapéutico , Masculino , Persona de Mediana Edad , Fosfatidilserinas/metabolismo
16.
Rev Bras Hematol Hemoter ; 36(5): 329-33, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25305164

RESUMEN

OBJECTIVE: The objective of this study was to verify the evolution of pregnancies in sickle cell patients followed at one institution over a period of 12 years (January 2000 to June 2012). METHODS: The study evaluated 34 pregnant women with sickle cell disease with a mean age of 23.9±5.3 years. The incidence of obstetric complications, non-obstetric complications linked to sickle cell disease and complications in the newborn were analyzed. RESULTS: A total of 26% of the cases reported previous miscarriages, 20% had preterm labor, 10% had pre-eclampsia, and 5% had gestational diabetes. Forty-one percent of the deliveries were cesarean sections and 29% of patients required blood transfusions. In respect to sickle cell disease, 62% of patients had vaso-occlusive crises, 29% had acute chest syndrome, 23% had urinary tract infection, 15% had impaired cardiac function and 6% developed pulmonary hypertension. Only one patient died in the postnatal period due to acute chest syndrome. The mean gestational age was 37.8±2.63 weeks, and mean newborn weight was 2.809±643.8g. There were seven fetal losses, including three stillbirths and four miscarriages. The impact of transfusion therapy on the incidence of maternal-fetal complications during pregnancy was evaluated. CONCLUSIONS: Pregnancy in sickle cell patients is still associated with complications. Although no statistical difference was observed between transfused and non-transfused women, there were no deaths (fetal or maternal) in transfused patients whereas one maternal death and three stillbirths occurred in non-transfused women. A larger study of sickle cell pregnant women will be necessary to elucidate the actual role of transfusion during pregnancy in sickle cell disease.

17.
Sao Paulo Med J ; 131(4): 238-43, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24141294

RESUMEN

CONTEXT AND OBJECTIVES Sickle cell disease (SCD) is the most common genetic disorder among people of African descent, affecting approximately 3,500 newborns each year in Brazil. Hydroxyurea (HU) is the only effective drug to treating patients with SCD, thereby reducing morbidity and mortality. The objective was to analyze the effects of HU on SCD patients at our institution. DESIGN AND SETTING Retrospective study conducted at a sickle cell centre in Ribeirão Preto, São Paulo, Brazil. METHODS We analyzed clinical and laboratory data on 37 patients. The hematological parameters and clinical events that occurred during the year before and the first year of treatment with HU were analyzed. The mean dose of HU was 24.5 ± 5.5 mg/kg/day. RESULTS There were rises in three parameters: hemoglobin (8.3 g/dl to 9.0 g/dl, P = 0.0003), fetal hemoglobin (HbF) (2.6% to 19.8%, P < 0.0001) and mean cell volume MCV (89 to 105 fl, P = 0.001); and reductions in the numbers of leukocytes (10,050/µl to 5,700/µl, P < 0.0001), neutrophils (6,200/µl to 3,400/µl, P = 0.001), platelets (459,000/µl to 373,000/µl, P = 0.0002), painful crises (1.86 to 0.81, P = 0.0014), acute chest syndromes (0.35 to 0.08, P = 0.0045), infections (1.03 to 0.5, P = 0.047), hospitalizations (1.63 to 0.53, P = 0.0013) and transfusions (1.23 to 0.1, P = 0.0051). CONCLUSION The patients presented clinical and hematological improvements, with an increase in HbF and a reduction in the infection rate, which had not been addressed in most previous studies.


Asunto(s)
Anemia de Células Falciformes/tratamiento farmacológico , Antidrepanocíticos/uso terapéutico , Hidroxiurea/uso terapéutico , Adolescente , Adulto , Análisis de Varianza , Anemia de Células Falciformes/sangre , Antidrepanocíticos/farmacología , Transfusión Sanguínea , Brasil , Niño , Índices de Eritrocitos/efectos de los fármacos , Femenino , Hemoglobina Fetal/efectos de los fármacos , Hemoglobina Falciforme/efectos de los fármacos , Humanos , Hidroxiurea/farmacología , Masculino , Estudios Retrospectivos , Estadísticas no Paramétricas , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
18.
Science ; 342(6160): 866-71, 2013 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-24136356

RESUMEN

Genetic mutations cause primary immunodeficiencies (PIDs) that predispose to infections. Here, we describe activated PI3K-δ syndrome (APDS), a PID associated with a dominant gain-of-function mutation in which lysine replaced glutamic acid at residue 1021 (E1021K) in the p110δ protein, the catalytic subunit of phosphoinositide 3-kinase δ (PI3Kδ), encoded by the PIK3CD gene. We found E1021K in 17 patients from seven unrelated families, but not among 3346 healthy subjects. APDS was characterized by recurrent respiratory infections, progressive airway damage, lymphopenia, increased circulating transitional B cells, increased immunoglobulin M, and reduced immunoglobulin G2 levels in serum and impaired vaccine responses. The E1021K mutation enhanced membrane association and kinase activity of p110δ. Patient-derived lymphocytes had increased levels of phosphatidylinositol 3,4,5-trisphosphate and phosphorylated AKT protein and were prone to activation-induced cell death. Selective p110δ inhibitors IC87114 and GS-1101 reduced the activity of the mutant enzyme in vitro, which suggested a therapeutic approach for patients with APDS.


Asunto(s)
Predisposición Genética a la Enfermedad , Síndromes de Inmunodeficiencia/genética , Síndromes de Inmunodeficiencia/patología , Fosfatidilinositol 3-Quinasas/genética , Infecciones del Sistema Respiratorio/genética , Infecciones del Sistema Respiratorio/patología , Fosfatidilinositol 3-Quinasa Clase I , Humanos , Síndromes de Inmunodeficiencia/inmunología , Linfocitos/inmunología , Mutación , Linaje , Fosfatos de Fosfatidilinositol/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Infecciones del Sistema Respiratorio/inmunología
19.
Rev Bras Hematol Hemoter ; 34(6): 426-9, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23323066

RESUMEN

OBJECTIVE: Sickle cell anemia and the interaction S/Beta thalassemia differ in hematological values due to microcytosis and hypochromia caused by the thalassemic mutation. The clinical benefit of long-term hydroxyurea treatment is undeniable in sickle cell disease with monitoring of the biological action of the drug being by the complete blood count. The objective of this work is to compare changes in some of the erythrocytic indexes between S/Beta thalassemia and sickle cell anemia patients on long-term hydroxyurea treatment. METHODS: The values of erythrocyte indexes (mean corpuscular volume and mean corpuscular hemoglobin) were compared in a retrospective study of two groups of patients (Sickle cell anemia and S/Beta thalassemia) on hydroxyurea treatment over a mean of six years. RESULTS: The quantitative values of the two parameters differed between the groups. Increases in mean corpuscular volume and reductions in mean corpuscular hemoglobin delay longer in S/Beta thalassemia patients (p-value = 0.018). CONCLUSION: Hematological changes are some of the beneficial effects of hydroxyurea in sickle cell disease as cellular hydration increases and the hemoglobin S concentration is reduced. The complete blood count is the best test to monitor changes, but the interpretation of the results in S/Beta thalassemia should be different.

20.
Anticancer Res ; 31(4): 1265-70, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21508374

RESUMEN

BACKGROUND: Human ether à go-go-1 (EAG1) potassium channels are potential tools for cancer diagnosis, prognosis and therapy. Epithelial-to-mesenchymal transition (EMT) is a likely mechanism by which tumor cells become malignant. We wondered whether EAG1 is regulated in human lung tumor cells undergoing EMT. MATERIALS AND METHODS: EMT was induced in A549 lung tumor cells with transforming growth factor beta (TGFß1). EAG1 gene expression was assesed by real-time RT-PCR and protein expression by flow cytometry. RESULTS: TGFß1 produced the expected changes in morphology, migration and gene expression associated to EMT. EAG1 gene and protein expression were up-regulated during EMT. Astemizole did not prevent EMT. CONCLUSION: Our results suggest that EAG1 channels participate in the acquisition of a malignant phenotype in lung tumor cells. Their potential role in EMT might not be uniquely related to their conducting function, in accordance with the reported tumor growth supported by non-conducting EAG1 channels.


Asunto(s)
Adenocarcinoma Bronquioloalveolar/genética , Adenocarcinoma Bronquioloalveolar/patología , Transición Epitelial-Mesenquimal , Canales de Potasio Éter-A-Go-Go/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Adenocarcinoma Bronquioloalveolar/metabolismo , Western Blotting , Diferenciación Celular , Movimiento Celular , Canales de Potasio Éter-A-Go-Go/metabolismo , Citometría de Flujo , Humanos , Neoplasias Pulmonares/metabolismo , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor de Crecimiento Transformador beta1/farmacología , Células Tumorales Cultivadas
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