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1.
J Biol Chem ; 291(48): 25096-25105, 2016 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-27758856

RESUMEN

Familial amyloidotic polyneuropathy (FAP) is a systemic amyloidosis mainly caused by amyloidogenic transthyretin (ATTR). This incurable disease causes death ∼10 years after onset. Although it has been widely accepted that conformational change of the monomeric form of transthyretin (TTR) is very important for amyloid formation and deposition in the organs, no effective therapy targeting this step is available. In this study, we generated a mouse monoclonal antibody, T24, that recognized the cryptic epitope of conformationally changed TTR. T24 inhibited TTR accumulation in FAP model rats, which expressed human ATTR V30M in various tissues and exhibited non-fibrillar deposits of ATTR in the gastrointestinal tracts. Additionally, humanized T24 (RT24) inhibited TTR fibrillation and promoted macrophage phagocytosis of aggregated TTR. This antibody did not recognize normal serum TTR functioning properly in the blood. These results demonstrate that RT24 would be an effective novel therapeutic antibody for FAP.


Asunto(s)
Neuropatías Amiloides Familiares/tratamiento farmacológico , Neuropatías Amiloides Familiares/inmunología , Anticuerpos Monoclonales de Origen Murino/inmunología , Macrófagos/inmunología , Fagocitosis/efectos de los fármacos , Prealbúmina/inmunología , Neuropatías Amiloides Familiares/patología , Animales , Anticuerpos Monoclonales de Origen Murino/uso terapéutico , Femenino , Humanos , Macrófagos/patología , Masculino , Ratones , Ratas
2.
J Biol Chem ; 287(17): 14023-39, 2012 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-22356913

RESUMEN

We prepared ß-sheet-rich recombinant full-length prion protein (ß-form PrP) (Jackson, G. S., Hosszu, L. L., Power, A., Hill, A. F., Kenney, J., Saibil, H., Craven, C. J., Waltho, J. P., Clarke, A. R., and Collinge, J. (1999) Science 283, 1935-1937). Using this ß-form PrP and a human single chain Fv-displaying phage library, we have established a human IgG1 antibody specific to ß-form but not α-form PrP, PRB7 IgG. When prion-infected ScN2a cells were cultured with PRB7 IgG, they generated and accumulated PRB7-binding granules in the cytoplasm with time, consequently becoming apoptotic cells bearing very large PRB7-bound aggregates. The SAF32 antibody recognizing the N-terminal octarepeat region of full-length PrP stained distinct granules in these cells as determined by confocal laser microscopy observation. When the accumulation of proteinase K-resistant PrP was examined in prion-infected ScN2a cells cultured in the presence of PRB7 IgG or SAF32, it was strongly inhibited by SAF32 but not at all by PRB7 IgG. Thus, we demonstrated direct evidence of the generation and accumulation of ß-sheet-rich PrP in ScN2a cells de novo. These results suggest first that PRB7-bound PrP is not responsible for the accumulation of ß-form PrP aggregates, which are rather an end product resulting in the triggering of apoptotic cell death, and second that SAF32-bound PrP lacking the PRB7-recognizing ß-form may represent so-called PrP(Sc) with prion propagation activity. PRB7 is the first human antibody specific to ß-form PrP and has become a powerful tool for the characterization of the biochemical nature of prion and its pathology.


Asunto(s)
Inmunoglobulina G/química , Neuroblastoma/metabolismo , Priones/química , Scrapie/metabolismo , Animales , Anticuerpos/química , Dicroismo Circular/métodos , Ingeniería Genética/métodos , Humanos , Inmunohistoquímica/métodos , Ratones , Microscopía de Fuerza Atómica/métodos , Microscopía Confocal/métodos , Biblioteca de Péptidos , Conformación Proteica , Pliegue de Proteína , Estructura Secundaria de Proteína
3.
Cell Tissue Res ; 343(2): 303-17, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21190118

RESUMEN

Although the tissue plasminogen activator/plasminogen system contributes to numerous brain functions, such as learning, memory, and anxiety behavior, little attention has as yet been given to the localization of plasminogen in the brain. We have investigated the localization of plasminogen in the adult mouse brain by using immunohistochemistry. In the hippocampus, plasminogen immunoreactivity was seen in the pyramidal cell layer as numerous punctate structures in neuronal somata. An electron-microscopic study further demonstrated that the plasminogen-immunoreactive punctate structures represented secretory vesicles and/or vesicle clusters. In the cerebral cortex, plasminogen immunoreactivity was evident in the somata of the layer II/III and V neurons. A quantitative analysis revealed that parvalbumin (PV)-positive neurons had more plasminogen-immunoreactive puncta compared with those of PV-negative neurons in the hippocampus and cerebral cortex. Plasminogen immunoreactivity was present throughout the hypothalamus, being particularly prominent in the neuronal somata of the organum vasculosum laminae terminalis, ventromedial preoptic nucleus, supraoptic nucleus, subfornical organ, medial part of the paraventricular nucleus (PVN), posterior part of the PVN, and arcuate hypothalamic nucleus. Thus, plasminogen is highly expressed in specific populations of hippocampal, cortical, and hypothalamic neurons, and plasminogen-containing vesicles are mainly observed at neuronal somata.


Asunto(s)
Corteza Cerebral/química , Hipocampo/química , Hipotálamo/química , Plasminógeno/análisis , Animales , Inmunohistoquímica , Masculino , Ratones , Ratones Endogámicos C57BL , Neuronas/química , Núcleo Hipotalámico Paraventricular/química , Plasminógeno/metabolismo
4.
Int Immunol ; 22(7): 561-70, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20497957

RESUMEN

We previously reported that intranasal challenge with ovalbumin (OVA) plus IL-18 induces airway hyperresponsiveness (AHR) and eosinophilic airway inflammation in mice with OVA-specific T(h)1 cells. These two conditions can be prevented by neutralizing anti-IFN-gamma and anti-IL-13 antibodies, respectively. The mice develop AHR and eosinophilic airway inflammation after challenge with OVA plus LPS instead of IL-18 and endogenous IL-18 is known to be involved. In contrast, IL-18 does not facilitate these changes in mice possessing OVA-specific T(h)2 cells. Here, we investigated whether IL-18 is involved in the development of asthma in mice immunized and challenged with bacterial proteins. Upon intranasal exposure to protein A (SpA) derived from Staphylococcus aureus, mice immunized with SpA exhibited AHR and peribronchial eosinophilic inflammation if IFN-gamma or IL-13 were present, respectively. The CD4(+) T cells from draining lymph nodes (DLNs) of the SpA-immunized and -challenged mice produced a robust IFN-gamma and IL-13 in response to immobilized anti-CD3 antibodies. Treatment with neutralizing anti-IL-18 antibodies prevented asthmatic inflammation concomitant with their impaired potential to express IFN-gamma and IL-13. Furthermore, naive mice that received the CD4(+) T cells from DLNs of SpA-immunized mice developed airway inflammation depending upon the presence of IL-18. Immunodeficient mice that received human PBMCs, which had been stimulated with SpA in vitro, developed dense peribronchial accumulation of human CD4(+) T cells upon SpA challenge. Neutralizing anti-human IL-18 antibodies protected against this airway inflammation. These results suggest the importance of IL-18 for the development of asthmatic inflammation associated with airway exposure to bacterial proteins.


Asunto(s)
Asma/inmunología , Proteínas Bacterianas/inmunología , Eosinofilia/inmunología , Inflamación , Interleucina-18/inmunología , Staphylococcus aureus/inmunología , Animales , Linfocitos T CD4-Positivos/inmunología , Inmunización , Interferón gamma/inmunología , Interleucina-13/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Desnudos
5.
Skin Res Technol ; 17(1): 75-81, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20923465

RESUMEN

BACKGROUND/PURPOSE: We observed that olfactory stimulation with scent of grapefruit oil elevated the activities of sympathetic nerves, and increased the plasma glycerol concentration and blood pressure. In contrast, olfactory stimulation with scent of lavender oil had opposite effects in rats. These suggest that changes in autonomic activities cause physiological functions via histaminergic H1 and H3 receptor. Moreover, it has been reported that somatic sensory stimulation affected autonomic neurotransmission. To examine effects of skin application of urea-containing cream on cutaneous arterial sympathetic nerve activity (CASNA), blood flow, and transepidermal water loss (TEWL). METHOD: The activity of CASNA was determined by electrophysiological method, and cutaneous blood flow was determined using laser flowmeter in urethane-anesthetized rats, TEWL was measured using VapoMeter in the back skin of HWY hairless rats. RESULTS: CASNA was markedly and significantly inhibited by skin application of 10% urea-containing cream, whereas cutaneous blood flow was significantly elevated via histaminergic H3-receptor. In conscious hairless rats, TEWL was significantly decreased 24 h after application of 10% urea-containing cream to the back skin. CONCLUSION: These findings suggest that skin application of 10% urea-containing cream increases the cutaneous blood flow and water retaining ability, and that histaminergic H3-receptors may mediate these effects.


Asunto(s)
Emolientes/farmacología , Flujo Sanguíneo Regional/efectos de los fármacos , Sistema Nervioso Simpático/efectos de los fármacos , Urea/farmacología , Agua/metabolismo , Administración Tópica , Anestésicos Intravenosos , Animales , Estado de Conciencia , Antagonistas de los Receptores Histamínicos/farmacología , Masculino , Maleatos/farmacología , Piperidinas/farmacología , Ratas , Ratas sin Pelo , Ratas Wistar , Receptores Histamínicos H3/metabolismo , Piel/irrigación sanguínea , Piel/inervación , Piel/metabolismo , Sistema Nervioso Simpático/fisiología , Uretano
6.
J Biochem ; 168(3): 231-241, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32271918

RESUMEN

This study introduces a novel monoclonal anti-α9 integrin antibody (MA9-413) with human variable regions, isolated by phage display technology. MA9-413 specifically binds to both human and mouse α9 integrin by recognizing a conserved loop region designated as L1 (amino acids 104-122 of human α9 integrin). MA9-413 inhibits human and mouse α9 integrin-dependent cell adhesion to ligands and suppresses synovial inflammation and osteoclast activation in a mouse model of arthritis. This is the first monoclonal anti-α9 integrin antibody that can react with and functionally inhibit both human and mouse α9 integrin. MA9-413 allows data acquisition both in animal and human pharmacological studies without resorting to surrogate antibodies. Since MA9-413 showed certain therapeutic effects in the mouse arthritis model, it can be considered as a useful therapy against rheumatoid arthritis and other α9 integrin-associated diseases.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Cadenas alfa de Integrinas/inmunología , Cadenas alfa de Integrinas/metabolismo , Animales , Anticuerpos Monoclonales/farmacología , Adhesión Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Línea Celular Tumoral , Técnicas de Visualización de Superficie Celular , Reacciones Cruzadas , Modelos Animales de Enfermedad , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Región Variable de Inmunoglobulina/inmunología , Inflamación/tratamiento farmacológico , Cadenas alfa de Integrinas/genética , Masculino , Ratones , Ratones Endogámicos DBA , Osteoclastos/metabolismo , Transfección , Resultado del Tratamiento
7.
J Biochem ; 143(4): 475-86, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18174189

RESUMEN

The pathogenesis of Alzheimer's disease involves conformational changes of A beta. A series of antibodies recognizing a distinct conformation of A beta (snapshot antibody) is useful for both understanding the mechanism of molecular conversion and identifying diagnostic and therapeutic reagents. As A beta with various conformations can be prepared in vitro under varying physicochemical conditions, snapshot antibodies can be isolated by directly binding to target molecules with antibody-displaying phages. We tested the feasibility of this idea. We show a feature of several A beta-reactive antibodies isolated from our human single-chain Fv antibody-phage library and particularly report the characteristics of an scFv clone, B6, selected from the fibrillar A beta 1-42-coated biopanning. B6 bound to fibrillar A beta 1-42 as well as globulomer A beta 1-42 but not to soluble A beta 1-42 or A beta 1-40. B6 inhibited A beta 1-42 fibril formation with 600 nM IC50 in spite of being the monovalent scFv form. Epitope analysis suggested that the binding site might be located at the beta2 sheet of the C-terminus of A beta 1-42. Although it is believed that N-terminus-recognizing antibodies tend to show the capability to inhibit A beta 1-42 fibrillation, B6 is the first human inhibitory antibody recognizing the C-terminus of A beta 1-42.


Asunto(s)
Péptidos beta-Amiloides/inmunología , Anticuerpos/inmunología , Bacteriófagos/genética , Secuencia de Aminoácidos , Péptidos beta-Amiloides/química , Anticuerpos/genética , Secuencia de Bases , Cartilla de ADN , Electroforesis en Gel de Poliacrilamida , Humanos , Datos de Secuencia Molecular , Conformación Proteica , Homología de Secuencia de Aminoácido
8.
J Biochem ; 143(5): 593-601, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18216066

RESUMEN

Monocyte chemotactic protein-1 (MCP-1, CC-chemokine ligand 2; CCL2) is involved in the development of various forms of chronic inflammations. Employing the naive human single-chain Fv displaying phage library, we established seven MCP-1-specific scFvs. The MC8 and MC32 clones exhibited blocking activity for the MCP-1-induced chemotaxis of THP-1 cells, in spite of their monovalency. The analysis of V gene usage showed that all clones bore the identical Vh1 gene, IGHV1-24*01, with variable DJ joining sequences, while their Vl usage was relatively varied, suggesting the preferential contribution of the Vh gene. Based on these findings, to minimize the deteriorative influences on the MCP-1 specificity of MC32, we aimed to achieve the affinity maturation of MC32 using MC32 L-chain shuffling library and select MC32 variants. Most MC32 variants increased their affinity by reducing the k(off) value with no influence of the antigen specificity. MC32 variants #22 or #56 showed approximately 15-fold higher affinity than MC32, indicating that the L-chain shuffling library is useful if the Vh is dominantly involved in the determination of the antigen specificity.


Asunto(s)
Anticuerpos Monoclonales/genética , Anticuerpos Monoclonales/farmacología , Quimiocina CCL2/antagonistas & inhibidores , Quimiocina CCL2/inmunología , Quimiotaxis/efectos de los fármacos , Barajamiento de ADN , Cadenas kappa de Inmunoglobulina/genética , Secuencia de Aminoácidos , Anticuerpos Monoclonales/inmunología , Afinidad de Anticuerpos , Humanos , Inmunoglobulina G/inmunología , Región Variable de Inmunoglobulina/química , Región Variable de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/inmunología , Cadenas kappa de Inmunoglobulina/química , Cadenas kappa de Inmunoglobulina/inmunología , Datos de Secuencia Molecular , Biblioteca de Péptidos , Homología de Secuencia de Aminoácido , Resonancia por Plasmón de Superficie
9.
Brain Res ; 1224: 1-11, 2008 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-18602091

RESUMEN

Kilon is a member of the IgLON family belonging to the immunoglobulin superfamily of cell adhesion molecules. In the present study, we investigated temporal and spatial changes of Kilon expression and its modulatory functions for synapse number using hippocampal cultured neurons. Kilon was observed to localize chiefly at axons and presynaptic terminals at early culture stage, however, it was seen mainly at dendritic postsynaptic spine of mature neurons at late culture stages. Kilon was solubilized with detergent treatment at early culture stages, while it resisted to extraction of the detergent in mature neurons. The overexpression of Kilon gene using a plasmid vector decreased the number of dendritic synapses at early culture stages, whereas the overexpression increased the number of dendritic synapses at late culture. These results demonstrate the alteration of modulatory function of Kilon for the number of dendritic synapses concomitant with changes in its localization and detergent solubility during neuronal culture development.


Asunto(s)
Moléculas de Adhesión Celular Neuronal/fisiología , Hipocampo/metabolismo , Neuronas/metabolismo , Sinapsis/metabolismo , Animales , Biomarcadores/análisis , Biomarcadores/metabolismo , Células CHO , Moléculas de Adhesión Celular Neuronal/química , Moléculas de Adhesión Celular Neuronal/genética , Diferenciación Celular/fisiología , Células Cultivadas , Cricetinae , Cricetulus , Dendritas/metabolismo , Dendritas/ultraestructura , Detergentes/farmacología , Vectores Genéticos/genética , Proteínas Fluorescentes Verdes , Hipocampo/ultraestructura , Neuronas/ultraestructura , Terminales Presinápticos/metabolismo , Terminales Presinápticos/ultraestructura , Ratas , Ratas Wistar , Solubilidad , Sinapsis/ultraestructura , Sinapsinas/análisis , Sinapsinas/metabolismo , Transfección
10.
Brain Res ; 1150: 200-6, 2007 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-17397805

RESUMEN

Perineuronal nets (PNs) consisting of chondroitin sulfate proteoglycans (CSPGs) and hyaluronic acid are associated with distinct neuronal populations in mammalian brain. Cortical areas abundant in PNs have been known to be less affected by neurotoxicity in human Alzheimer's disease. In the present study, we examined whether PNs protect the neurotoxicity caused by amyloid beta-protein (Abeta), a major constituent of senile plaques in Alzheimer's disease using cortical neurons of dissociated culture. Double labeling experiments using confocal microscopy showed that the neurons associated with PNs were visualized with the anti-CSPG antibody in dissociated cortical culture. The analysis of reverse transcription-polymerase chain reaction revealed that mRNA expression of chondroitin sulfotransferases, CSPG-specific enzymes, was detected in neuronal culture, indicating that cultured cortical neurons are able to synthesize CSPGs and construct PNs structure. The treatment of Abeta1-42 showed significant neurotoxicity on PNs-free cortical neurons, however, it did not reveal neurotoxicity on PNs-associated neurons. Moreover, it was shown that the treatment of Abeta1-42 was able to kill PNs-associated neurons after the removal of chondroitin sulfate (CS) glycosaminoglycans with chondroitinase ABC. The treatment of glutamate killed not only PNs-free cortical neurons but also PNs-associated neurons. These results suggest that CS glycosaminoglycans on PNs are responsible for protecting neurons from Abeta1-42 neurotoxicity.


Asunto(s)
Péptidos beta-Amiloides/toxicidad , Corteza Cerebral/citología , Proteoglicanos Tipo Condroitín Sulfato/metabolismo , Neuronas/efectos de los fármacos , Fragmentos de Péptidos/toxicidad , Animales , Muerte Celular/efectos de los fármacos , Células Cultivadas , Condroitina ABC Liasa/farmacología , Relación Dosis-Respuesta a Droga , Embrión de Mamíferos , Ácido Glutámico/farmacología , Ácido Hialurónico , Proteínas Asociadas a Microtúbulos/metabolismo , Neuronas/citología , ARN Mensajero/biosíntesis , Ratas , Ratas Wistar , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Sulfotransferasas/metabolismo , Factores de Tiempo
11.
Brain Res ; 1165: 5-14, 2007 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-17658490

RESUMEN

Opioid-binding cell adhesion molecule (OBCAM) is the member of the IgLON family, a subgroup of the immunoglobulin superfamily. In the present study, the functions and dynamics of OBCAM were investigated in hippocampal neurons in vitro. Western blotting revealed that OBCAM expression was low at early stages of culture but it was increased as culture development. Double labeling immunofluorescence microscopy showed that OBCAM immunoreactivity was localized mainly at postsynaptic spines labeled with phalloidin and anti-PSD-95. The inhibition of OBCAM function with the specific antibody resulted in a significant decrease in the number of synapses on dendrites compared with control mouse IgG. The suppression of OBCAM expression using the antisense oligodeoxynucleotide also impaired the formation of synapses compared with control universal ones. The overexpression of OBCAM mRNA using a plasmid vector augmented the formation of synapses. Moreover, the internalization of OBCAM was promoted with increased neuronal activity by 4-aminopyridine. This internalization was reduced with the treatment of filipin, a sterol agent, indicating that this process is a raft-dependent pathway. These results indicate that OBCAM is a synaptic cell adhesion molecule concerning synaptogenesis and its surface localization is dynamically regulated in response to neuronal activity.


Asunto(s)
Proteínas Portadoras/metabolismo , Moléculas de Adhesión Celular/metabolismo , Regulación de la Expresión Génica/fisiología , Neuronas/metabolismo , Dinámicas no Lineales , Sinapsis/fisiología , 4-Aminopiridina/farmacología , Animales , Anticuerpos/farmacología , Encéfalo/citología , Proteínas Portadoras/genética , Proteínas Portadoras/inmunología , Moléculas de Adhesión Celular/genética , Moléculas de Adhesión Celular/inmunología , Células Cultivadas , Espinas Dendríticas/efectos de los fármacos , Espinas Dendríticas/metabolismo , Embrión de Mamíferos , Proteínas Ligadas a GPI , Regulación de la Expresión Génica/efectos de los fármacos , Proteínas Fluorescentes Verdes/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Neuronas/citología , Oligonucleótidos Antisentido/farmacología , Bloqueadores de los Canales de Potasio/farmacología , Transporte de Proteínas/efectos de los fármacos , Transporte de Proteínas/fisiología , Ratas , Ratas Wistar , Sinapsinas/metabolismo , Factores de Tiempo , Transfección
12.
Int Immunopharmacol ; 7(11): 1460-70, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17761350

RESUMEN

The presence of thrombin-cleaved form of osteopontin well correlated with various inflammatory disease activities in not only rodents, but also humans. We previously demonstrated that the blocking of the interaction of a cryptic epitope within osteopontin, which is exposed by thrombin cleavage, with its integrins by specific antibody recognizing cryptic epitope of mouse osteopontin, could significantly inhibits the development of arthritis in mice. We generated a murine monoclonal antibody, 2K1, specifically recognizing a cryptic epitope of human osteopontin, SVVYGLR. We constructed a chimeric antibody, C2K1 in which variable region of 2K1 was fused with human IgG1 constant region. In the present study, we investigated whether the therapeutic administration of C2K1 could ameliorate the established collagen-induced arthritis in cynomolgus monkey. Thus, C2K1 was injected after the onset of arthritis. The inhibition of joint swelling by C2K1 became evident at 4 to 5 weeks after initiation of arthritis, when blood level of C2K1 was peaked. Joint swelling reappeared along with the sharp decline of C2K1 blood levels at 6 weeks. Importantly, destruction of bone and cartilage in joints was still significantly prevented at 10 weeks when blood level of C2K1 was quite low if any and anti-C2K1 antibody emerged. These results demonstrate that neutralizing antibody against the cryptic epitope of osteopontin can be a future therapeutic choice for patients with rheumatoid arthritis.


Asunto(s)
Anticuerpos/uso terapéutico , Artritis Experimental/tratamiento farmacológico , Artritis Experimental/inmunología , Colágeno/inmunología , Colágeno/toxicidad , Macaca fascicularis/inmunología , Osteopontina/inmunología , Secuencia de Aminoácidos , Animales , Antiinflamatorios no Esteroideos/química , Antiinflamatorios no Esteroideos/uso terapéutico , Anticuerpos/química , Anticuerpos/inmunología , Anticuerpos/farmacología , Artritis Experimental/patología , Femenino , Datos de Secuencia Molecular , Osteopontina/antagonistas & inhibidores , Osteopontina/metabolismo , Proteínas Recombinantes
13.
J Biosci Bioeng ; 103(2): 155-60, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17368398

RESUMEN

An experimental evolution with selection based on binding affinity to DNA was carried out on a library of phage-displayed random polypeptides of about 140 amino acid residues. First, we constructed a system to artificially evolve phage-displayed random polypeptides toward binding to a target DNA containing a restriction enzyme site, in which random polypeptides capable of binding the DNA were recovered as complexes with the target DNA by digestion with the restriction enzyme. The experimental evolution cycle, including the above selection system and random mutagenesis for generating the next mutant library, was repeated until the fourth generation. The ability to bind to the DNA was enhanced per generation. In the fourth generation, convergence of the selected clones to a dominant sequence was observed. These results indicate that the newly constructed selection system is effective for exploring the evolvability of random polypeptides towards DNA-binding proteins.


Asunto(s)
Proteínas de Unión al ADN/biosíntesis , Evolución Molecular Dirigida/métodos , Biblioteca de Péptidos , Secuencia de Aminoácidos , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Datos de Secuencia Molecular
14.
Curr Alzheimer Res ; 14(3): 295-302, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-27829339

RESUMEN

BACKGROUND: The ever-increasing number of people living with Alzheimer's disease urges to develop more effective therapies. Despite considerable success, anti-Alzheimer immunotherapy still faces the challenge of intracerebral and intracellular delivery. This work introduces in situ production of anti-amyloid beta (Aß) antibody after intracerebral injection of PEG-PAsp(DET)/mRNA polyplexes as a novel immunotherapy approach and a safer alternative compared to high systemic antibodies doses or administration of adenovirus encoding anti- Aß antibodies. METHODS: We used mRNA encoding three different Aß-specific scFV with a secretion signal for passive immunotherapy. scFv contained a 6xHis-tag for immuno-detection. The secretion signal from IL2 (IL2ss) was added to allow extracellular engagement of senile plaques. Aß affinity of scFv was measured by surface plasmon resonance. To allow intracellular delivery, scFv were administered as polyplexes formed with our smart copolymer polyethylene glycol-poly[N'-[N-(2-aminoethyl)-2-aminoethyl] aspartamide] [PEG-PAsp (DET)]. We evaluated scFv expression in cellulo by Western blot and ELISA, their ability to disaggregate amyloid aggregates by thioflavine T assay. Moreover, in vivo expression and therapeutic activity were evaluated in a murine amyloidosis model, by anti-6xHis-tag ELISA and anti- Aß ELISA, respectively. RESULTS: The selected anti-amyloid beta scFv showed affinity towards Aß and disaggregated Aß fibers in vitro. Whereas both DNA and mRNA transfection led to scFV expression in cancer cells, only mRNA led to detectable scFv expression in primary neurons. In addition, the use of IL2ss increased by 3.4-fold scFv secretion by primary neurons over mRNA polyplexes devoid of secretion signal. In vivo, a 3 to 11- fold of intracranial scFv levels was measured for mRNA compared to DNA polyplexes and higher in vivo scFv levels were obtained with mRNA containing IL2ss over non-secreted mRNA. Intracranial injection of anti-Aß mRNA polyplexes with IL2ss resulted in 40 % Aß decrease in an acute amyloidosis model; with no decrease detected with control scFv mRNA nor DNA polyplexes. However, no Aß decrease was detected in a more challenging transgenic model of Alzheimer's disease. CONCLUSION: Our results introduce a concerted approach not only for Alzheimer's disease treatment but also for immunotherapy against neurological diseases. The effectivity of our platform required the intracranial delivery of anti-Aß scFv as mRNA not DNA, as mRNA with an IL2ss secretion sequence to favor engagement of Aß in the amyloidosis model, complexation with a smart copolymer for efficient transfection of primary neurons and to achieve detectable mRNA expression in the brain during 48h. Amyloid burden decrease in an acute amyloidosis model was only achieved when these three factors (mRNA coding scFv, smart copolymer, IL2ss) were integrated into a single formulation.


Asunto(s)
Enfermedad de Alzheimer/terapia , Péptidos beta-Amiloides/inmunología , Encéfalo/inmunología , Inmunización Pasiva , ARN Mensajero/administración & dosificación , Anticuerpos de Cadena Única/biosíntesis , Enfermedad de Alzheimer/inmunología , Animales , Supervivencia Celular , Modelos Animales de Enfermedad , Femenino , Células HEK293 , Humanos , Ratones Endogámicos C57BL , Ratones Transgénicos , Neuronas/inmunología , Placa Amiloide/inmunología , Placa Amiloide/terapia , Polietilenglicoles , ARN Mensajero/genética , ARN Mensajero/metabolismo , Anticuerpos de Cadena Única/genética , Anticuerpos de Cadena Única/inmunología
15.
Behav Brain Res ; 297: 251-8, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26475511

RESUMEN

Several green leaf volatiles have anxiolytic/antidepressant properties and attenuate adrenocortical stress response in rodents. However, it remains unknown whether a mixture of cis-3-hexenol and trans-2-hexenal so-called 'green odor (GO)' affects fear-associated post-traumatic stress disorder (PTSD)-like behavior. In the present study, fear memory of the initial conditioning stimulus was stably maintained by weekly presentation of conditioned tone. Examination of open field behavior, acoustic startle response, prepulse inhibition, and immobility in the forced swim test for 2 weeks after initial conditioning revealed that conditioned rats sustained anxiety, enhanced startle response, hypervigilance, depression-like behavior, and hypocortisolism, which is consistent with PTSD symptoms. Daily, not acute, GO presentation facilitated fear extinction and reduced PTSD-like behavioral and endocrinal responses. To further investigate the mechanism of effect of GO, we examined the effect of paroxetine (a selective serotonin reuptake inhibitor), p-chlorophenylalanine (PCPA, an irreversible serotonin synthesis inhibitor), alone or in combination of GO on PTSD-like phenotype. The alleviative effects of GO were masked by simultaneous paroxetine administration. PCPA-induced serotonin depletion abolished the effects of GO. Our results suggest that daily GO presentation facilitates fear extinction and prevents development of PTSD-like symptoms.


Asunto(s)
Aldehídos/farmacología , Hexanoles/farmacología , Psicotrópicos/farmacología , Trastornos por Estrés Postraumático/prevención & control , Animales , Condicionamiento Psicológico/efectos de los fármacos , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Conducta Exploratoria/efectos de los fármacos , Extinción Psicológica/efectos de los fármacos , Miedo/efectos de los fármacos , Fenclonina/farmacología , Masculino , Actividad Motora/efectos de los fármacos , Paroxetina/farmacología , Fenotipo , Inhibición Prepulso/efectos de los fármacos , Distribución Aleatoria , Ratas Sprague-Dawley , Reflejo de Sobresalto/efectos de los fármacos , Trastornos por Estrés Postraumático/fisiopatología
16.
J Biochem ; 159(2): 261-70, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26475674

RESUMEN

Fibrinogen is a large and complex glycoprotein containing two sets of each of three different chains (α, ß and γ). There have been no reports of high-level expression of fibrinogen at commercial levels using mammalian cultured cells such as CHO cells because of the difficulty in highly expressing a protein with such a complex structure. We achieved high-level (1.3 g/l or higher) expression of recombinant human fibrinogen using CHO DG44 cells by optimizing the expression system and culture conditions. We also succeeded in establishing a high-recovery preparation method for recombinant fibrinogen that rarely yields degraded products. To characterize the properties of the recombinant human fibrinogen, we performed SDS-PAGE; western blotting of the α, ß and γ chains using specific antibodies and scanning electron microscopy observations of fibrin fibres. We also evaluated the functional equivalence between recombinant fibrinogen and plasma fibrinogen with respect to the release of fibrinopeptides initiated by thrombin and its cross-linking properties. The basic properties of recombinant fibrinogen showed no apparent differences from those of plasma fibrinogen. Here, we report the development of methods for the culture and preparation of recombinant human fibrinogen of satisfactory quality that can be scaled up to the commercial level.


Asunto(s)
Productos Biológicos/aislamiento & purificación , Productos Biológicos/metabolismo , Fibrinógeno/biosíntesis , Fibrinógeno/aislamiento & purificación , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/aislamiento & purificación , Animales , Western Blotting , Células CHO , Cricetinae , Cricetulus , Electroforesis en Gel de Poliacrilamida , Fibrina/metabolismo , Humanos , Microscopía Electrónica de Rastreo , Trombina/metabolismo
17.
J Biochem ; 138(4): 433-42, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16272137

RESUMEN

IL-18 is an important regulator in both innate and acquired immune responses. The aberrant expression of IL-18 is associated with severe inflammatory conditions, such as autoimmune diseases and allergies. Thus, human antibodies with inhibitory activity on IL-18 signaling may be useful for therapeutic applications. We report here the first establishment of an antagonistic anti-IL-18 complete human antibody, h18-108, employing a human single chain antibody (scFv)-displaying phage library. The h18-108 scFv inhibited the IFN-gamma production of a human myelomonocytic cell line, KG-1. Flow cytometry analysis showed that h18-108 blocked the binding of IL-18 to KG-1 cells. Epitope mapping analysis using two kinds of random peptide-displaying phage libraries and an IL-18 alanine mutant (D98A) demonstrated that the h18-108 scFv binds to the site 3 of IL-18, which is suggested to be an association site with the IL-18 receptor beta. The complete human Fab and IgG forms of h18-108 have been successfully constructed to attain increases in both binding affinity and inhibitory activity.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Interleucina-18/inmunología , Secuencia de Aminoácidos , Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/uso terapéutico , Afinidad de Anticuerpos , Especificidad de Anticuerpos , Sitios de Unión de Anticuerpos , Ensayo de Inmunoadsorción Enzimática , Mapeo Epitopo , Humanos , Fragmentos Fab de Inmunoglobulinas/química , Fragmentos Fab de Inmunoglobulinas/metabolismo , Inmunoglobulina G/química , Inmunoglobulina G/metabolismo , Región Variable de Inmunoglobulina/química , Técnicas Inmunológicas , Interferón gamma/biosíntesis , Interleucina-18/antagonistas & inhibidores , Interleucina-18/metabolismo , Subunidad alfa del Receptor de Interleucina-18 , Datos de Secuencia Molecular , Biblioteca de Péptidos , Receptores de Interleucina/antagonistas & inhibidores , Receptores de Interleucina/metabolismo , Receptores de Interleucina-18 , Transducción de Señal/efectos de los fármacos
18.
J Neuroimmunol ; 285: 31-40, 2015 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-26198916

RESUMEN

Microglia are resident immunocompetent cells having important roles in innate immunity in the brains. In the present study, we found that a single lipopolysaccharide (LPS) administration significantly increased microglial proliferation in the fornix and dentate gyrus (DG) but not the cerebral cortex and corpus callosum of adult mice. LPS-induced microglial proliferation was especially robust at the white matter of the fornix. The density of microglia increased in the fornix and DG for roughly one week and returned to basal levels at least 20days after a single LPS administration. Consecutive LPS administration did not induce such dramatic increase of microglial proliferation in the fornix. The inhibition of vascular endothelial growth factor signaling by AZD2171 largely suppressed LPS-induced increase of microglial proliferation in the fornix. In conclusion, the present study indicates that the hippocampal neuronal system has a higher proliferative microglial capability against LPS-induced inflammatory administration compared with other brain regions.


Asunto(s)
Axones/metabolismo , Proliferación Celular/fisiología , Fórnix/citología , Fórnix/metabolismo , Lipopolisacáridos/toxicidad , Microglía/metabolismo , Animales , Axones/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Fórnix/efectos de los fármacos , Hipocampo/citología , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Lipopolisacáridos/administración & dosificación , Masculino , Ratones , Ratones Endogámicos ICR , Microglía/efectos de los fármacos , Vías Nerviosas/citología , Vías Nerviosas/efectos de los fármacos , Vías Nerviosas/metabolismo
19.
J Biosci Bioeng ; 120(4): 432-7, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25735923

RESUMEN

In this study, we established stable cell lines producing 1.5 mg/mL recombinant human prothrombin in 400-L fed-batch culture, using CHO DG44 cells as a host cell line. And we also established a recombinant human α-thrombin purification process that produces a purified product suitable for use as a biopharmaceutical, by using recombinant ecarin from CHO DG44 cells, achieving a total yield of approximately 27% of prothrombin in culture medium. The establishment of stable cell lines with high expression levels, long-term passage stability and satisfactory scale-up are essential to ensure the stable supply of biopharmaceuticals. Furthermore, biopharmaceuticals must be of high quality to assure safety and effectiveness in target applications. We had previously reported that recombinant human prethrombin-2 expression level in a stable cell line established using the mouse myeloma cells, Sp2/0-Ag14, reached 200 µg/mL using animal-free materials in 50-L fed-batch culture. However, the productivity was insufficient to completely replace α-thrombin in human plasma preparations. By employing CHO DG44 cells as a host cell line, we had established a stable cell line and achieved significant improvements in quality, productivity of recombinant human α-thrombin manufacture suitable for use as a biopharmaceutical.


Asunto(s)
Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/aislamiento & purificación , Trombina/biosíntesis , Trombina/aislamiento & purificación , Animales , Técnicas de Cultivo Celular por Lotes , Células CHO , Cricetinae , Cricetulus , Medios de Cultivo/química , Endopeptidasas/genética , Endopeptidasas/metabolismo , Humanos , Protrombina/análisis , Protrombina/biosíntesis , Proteínas Recombinantes/uso terapéutico , Trombina/uso terapéutico
20.
J Neuroimmunol ; 278: 144-58, 2015 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-25595264

RESUMEN

The sensory circumventricular organs (CVOs) comprise the organum vasculosum of the lamina terminalis (OVLT), subfornical organ (SFO), and area postrema (AP) and lack the blood-brain barrier. The expression of Toll-like receptor 4 (TLR4) was seen at astrocytes throughout the sensory CVOs and at microglia in the AP and solitary nucleus around the central canal. The peripheral and central administration of lipopolysaccharide induced a similar pattern of nuclear translocation of STAT3. A microglia inhibitor minocycline largely suppressed lipopolysaccharide-induced astrocytic nuclear translocation of STAT3 in the OVLT and AP, but its effect was less in the SFO.


Asunto(s)
Encéfalo/anatomía & histología , Órganos Circunventriculares/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Lipopolisacáridos/farmacología , Factor de Transcripción STAT3/metabolismo , Receptor Toll-Like 4/metabolismo , Animales , Astrocitos/efectos de los fármacos , Astrocitos/metabolismo , Encéfalo/efectos de los fármacos , Proteínas de Unión al Calcio/metabolismo , Relación Dosis-Respuesta a Droga , Vías de Administración de Medicamentos , Proteína Ácida Fibrilar de la Glía/metabolismo , Laminina/metabolismo , Antígenos Comunes de Leucocito/metabolismo , Masculino , Ratones , Ratones Endogámicos ICR , Proteínas de Microfilamentos/metabolismo , Microscopía Confocal , Minociclina/farmacología , Factores de Tiempo
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