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1.
Mol Cell Endocrinol ; 317(1-2): 25-30, 2010 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-20026378

RESUMEN

Myostatin is a catabolic regulator of skeletal muscle mass. The purpose of this study was to determine the effect of resistance training for 8 weeks in conjunction with creatine supplementation on muscle strength, lean body mass, and serum levels of myostatin and growth and differentiation factor-associated serum protein-1 (GASP-1). In a double-blinded design 27 healthy male subjects (23.42+/-2.2 years) were assigned to control (CON), resistance training+placebo (RT+PL) and resistance training+creatine supplementation (RT+CR) groups. The protocol consisted of 3 days per week of training for 8 weeks, each session including three sets of 8-10 repetitions at 60-70% of 1 RM for whole-body exercise. Blood sampling, muscular strength testing and body composition analysis (full body DEXA) were performed at 0, 4th and 8th weeks. Myostatin and GASP-1 was measured. Resistance training caused significant decrease in serum levels of myostatin and increase in that of GASP-1. Creatine supplementation in conjunction with resistance training lead to greater decreases in serum myostatin (p<0.05), but had not additional effect on GASP-1 (p>0.05). The effects of resistance training on serum levels of myostatin and GASP-1, may explain the increased muscle mass that is amplified by creatine supplementation.


Asunto(s)
Creatina/administración & dosificación , Creatina/farmacología , Miostatina/sangre , Proteínas/metabolismo , Entrenamiento de Fuerza , Proteínas de Transporte Vesicular/sangre , Administración Oral , Composición Corporal/efectos de los fármacos , Creatina/orina , Dieta , Suplementos Dietéticos , Humanos , Péptidos y Proteínas de Señalización Intercelular , Masculino , Fuerza Muscular/efectos de los fármacos , Adulto Joven
2.
Biochemistry (Mosc) ; 73(8): 929-36, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18774940

RESUMEN

The interaction of native calf thymus DNA with the Pd(II) complex, PdCl2(LL) (LL = chelating diamine ligand: N,N-dimethyltrimethylenediamine), in 10 mM Hepes aqueous solutions at neutral pH has been monitored as a function of metal complex/DNA molar ratio by UV absorption spectrophotometry, circular dichroism (CD), viscosimetry, and fluorescence spectroscopy. The results support two modes of interaction. In particular, this complex showed absorption hypochromism and then hyperchromism, increase in melting temperature, and some structural changes in specific viscosity when bound to calf thymus DNA. The binding constant determined using absorption measurement is 2.69.10(3) M(-1). As evidenced by the increasing fluorescence of methylene blue-DNA solutions in the presence of increasing amounts of metal complex, PdCl(2)(LL) is able to displace the methylene blue intercalated into DNA, but not so completely, as indicated by partial intercalation. CD spectral changes in two steps and viscosity decrease confirm our conclusions.


Asunto(s)
ADN/metabolismo , Diaminas/metabolismo , Paladio/metabolismo , Animales , Bovinos , Dicroismo Circular , ADN/química , Diaminas/química , Ligandos , Desnaturalización de Ácido Nucleico , Paladio/química , Espectrometría de Fluorescencia , Viscosidad
3.
Hybridoma (Larchmt) ; 26(4): 217-22, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17725383

RESUMEN

Hybridomas secreting monoclonal antibodies (MAbs) producing stable, specific and high affinity against human serum albumin (HSA) have been established. The aim of the present study was the production of MAbs that will be potentially used in designing immunoassay methods especially immunochromatography assay kit for screening of microalbuminuria (MAU) in the early detection of diabetic and nondiabetic nephropathy. The hybridomas were obtained by fusion of spleen cells from immunized mice with mouse myeloma cell line (SP2). After limiting dilutions three clones producing antibodies were designed as EMRC1-3, which displayed different pattern of fine specificity for HSA and low cross reaction with other proteins as elucidated by inhibition enzyme-linked immunosorbent assay (ELISA). These clones were found to be of immunoglobulin G (IgG) class with k light chain. Subclass determination showed that all three MAbs secreted IgG1 type of antibody. The results of affinity purification for the two selected clones (EMRC1 and EMRC3) displayed high affinity with no cross reactivity with any of the related protein molecules. The stable hybridomas secreting anti-HSA were expanded in 50-mL flasks for large-scale production of the required antibodies. The standard curves were constructed with a sensitivity of 10 pg per well covering up to 100 ng per well. The high binding activity to HSA antigen and having no cross reactivity with other related molecules illustrated the potential application of these antibodies as an immunodiagnostic reagent in designing an immunochromatography assay kit for screening of MAU in diabetic and nondiabetic patients.


Asunto(s)
Anticuerpos Monoclonales/biosíntesis , Anticuerpos Monoclonales/química , Albúmina Sérica/inmunología , Animales , Anticuerpos Monoclonales/aislamiento & purificación , Especificidad de Anticuerpos , Células Clonales , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Hibridomas , Ratones , Ratones Endogámicos BALB C
4.
J Immunoassay Immunochem ; 27(2): 139-49, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16711252

RESUMEN

A new competitive enzyme linked immunosorbent assay was developed in this study. Monoclonal antibody (PR81) against the tandem repeat of the core protein was prepared, characterized, purified, and conjugated to HRP. This antibody exhibited no cross reactions with proteins such as bovine serum albumin, keyhole limpet homocyanin, human serum albumin, casein, human milk fat globin (HMFG), and peptone. The native cancerous MUC1 protein was purified from ascites fluid of a patient suffering from small cell lung carcinoma by immunoaffinity chromatography and used as a standard preparation in the assay buffer. The standard curve was constructed following a competitive procedure in the range of 0-200 U/mL. The level of MUC1 in normal and cancerous samples was compared following this procedure and using available CA15-3 EIA (Can Ag), as well as LIAISON CA15-3 commercial kits. The correlation coefficient between the procedure reported in this work (MRP83-CA15-3) and CA15-3 EIA (Can Ag) was 0.68 and was 0.95 with the LIAISON CA15-3 kit. We concluded that the present assay can detect MUC1 in breast cancer patients with great sensitivity and accuracy.


Asunto(s)
Neoplasias de la Mama/química , Ensayo de Inmunoadsorción Enzimática/métodos , Mucina-1/análisis , Animales , Anticuerpos Monoclonales , Neoplasias de la Mama/inmunología , Bovinos , Reacciones Cruzadas , Ensayo de Inmunoadsorción Enzimática/normas , Femenino , Humanos , Mucina-1/genética , Mucina-1/inmunología , Estándares de Referencia , Secuencias Repetidas en Tándem
5.
Tumour Biol ; 25(4): 179-87, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15557755

RESUMEN

EGFRvIII is the type III deletion mutant form of the epidermal growth factor receptor (EGFR) with transforming activity. This tumor-specific antigen is ligand independent, contains a constitutively active tyrosine kinase domain and has been shown to be present in a number of human malignancies. In this study, we report the production and characterization of camel antibodies that are directed against the external domain of the EGFRvIII. Antibodies developed in camels are smaller (i.e. IgG2 and IgG3 subclasses lack light chains) than any other conventional mammalian antibodies. This property of camel antibodies makes them ideal tools for basic research and other applications such as tumor imaging and cancer therapy. In the present study, camel antibodies were generated by immunization of camelids (Camelus bactrianus and Camelus dromedarius) with a synthetic 14-amino acid peptide corresponding to the mutated sequence of the EGFR, tissue homogenates of several patients with human glioblastoma, medulloblastoma and aggressive breast carcinoma, as well as EGFR-expressing cell lines. Three subclasses of camel IgG [conventional (IgG1, 160 kD) and heavy chain-only antibodies (IgG2 and IgG3, 90 kD)] were separated by their different binding properties to protein A and protein G affinity columns. The anti-EGFRvIII peptide antibodies from immunized camels were purified further using the EGFRvIII synthetic peptide affinity column. The purified anti-EGFRvIII peptide camel antibodies selectively bound to the EGFRvIII peptide and affinity-purified EGFRvIII from malignant tissues and detected a protein band of 140 kD from malignant tissues by Western blot. Affinity analysis showed that the antibodies from C. bactrianus and C. dromedarius reacted with peptide and antigen purified from a small cell lung cancer ascitic fluid with affinities of 2 x 10(8) and 5 x 10(7)M(-1) to the same extent, respectively. Since the functional antigen-binding domain of the anti-EGFRvIII antibodies in camels is much simpler and located only on the heavy chains of proteins, we are currently developing recombinant and smaller versions of the variable domain of these naturally occurring heavy-chain antibodies (V(HH)) for use in tumor imaging and cancer therapy.


Asunto(s)
Camelus/inmunología , Receptores ErbB/genética , Genes erbB-1/inmunología , Animales , Afinidad de Anticuerpos , Especificidad de Anticuerpos , Línea Celular Tumoral , Ensayo de Inmunoadsorción Enzimática , Receptores ErbB/inmunología , Humanos , Inmunoglobulina G/sangre , Fragmentos de Péptidos/inmunología , Eliminación de Secuencia
6.
Tumour Biol ; 25(5-6): 296-305, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15627895

RESUMEN

Camelids have a unique immune system capable of producing single-domain heavy-chain antibodies. The antigen-specific domain of these heavy-chain IgGs (VHH) are the smallest binding units produced by the immune system. In this study, we report the isolation and characterization of several binders against the epidermal growth factor receptor (EGFR) vIII retrieved from immune library of camels (Camelus bactrianus and Camelus dromedarius). The EGFRvIII is a ligand-independent, constitutively active, mutated form of the wild-type EGFR. The expression of EGFRvIII has been demonstrated in a wide range of human malignancies, including gliomas, and breast, prostate, ovarian and lung cancer. Camels were immunized with a synthetic peptide corresponding to a mutated sequence and tissue homogenates. Single-domain antibodies (VHH) were directly selected by panning a phage display library on successively decreasing amounts of synthetic peptide immobilized on magnetic beads. The anti-EGFRvIII camel single-domain antibodies selectively bound to the EGFRvIII peptide and reacted specifically with the immunoaffinity-purified antigen from a non-small cell lung cancer patient. These antibodies with affinities in the nanomolar range recognized the EGFRvIII peptide and affinity-purified mutated receptor. We concluded that using the phage display technique, antigen-specific VHH antibody fragments are readily accessible from the camelids. These antibodies may be good candidates for tumor-diagnostic and therapeutic applications.


Asunto(s)
Anticuerpos Monoclonales/análisis , Receptores ErbB/genética , Receptores ErbB/inmunología , Inmunoglobulina G/inmunología , Animales , Formación de Anticuerpos , Biomarcadores de Tumor/análisis , Neoplasias de la Mama/inmunología , Camelus/inmunología , Carcinoma de Pulmón de Células no Pequeñas/inmunología , Femenino , Neoplasias de Cabeza y Cuello/inmunología , Humanos , Inmunización/veterinaria , Fragmentos de Inmunoglobulinas , Cadenas Pesadas de Inmunoglobulina , Neoplasias Pulmonares/inmunología , Linfocitos/inmunología , Biblioteca de Péptidos , Células Tumorales Cultivadas , Neoplasias de la Vulva/inmunología
7.
Hybrid Hybridomics ; 22(3): 153-8, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12954100

RESUMEN

A monoclonal antibody (MAb) was generated by immunizing BALB/c mice with homogenized breast cancerous tissues. This antibody (PR81) was found to be of IgG(1) class and subclass, containing kappa light chain. PR81 reacted with either the membrane extracts of several breast cancerous tissues or the cell surface of some MUC1 positive cell lines (MCF-7, BT-20 and T-47D) tested by enzyme immunoassay and for MCF-7 by immunofluorescence method. PR81 also reacted with two synthetic 27 and 16-amino acid peptides, TSA-P1-24 and A-P1-15, respectively, which included the core tandem repeat sequence of MUC1. However, this antibody did not react with a synthetic 14 amino acid peptide that has no similarity with tandem repeat found in MUC1. The generated antibody had good and similar affinities (2.19 x 10(8) M(-1)) toward TSA-P1-24 and A-P1-15, which are mainly shared in the hydrophilic sequence of PDTRPAP. Through Western blot analysis of homogenized breast tissues, PR81 recognized only a major band of 250 kDa. This band is stronger in malignant tissue than benign and normal tissues.


Asunto(s)
Anticuerpos Monoclonales/química , Mucina-1/química , Animales , Western Blotting , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Relación Dosis-Respuesta Inmunológica , Ensayo de Inmunoadsorción Enzimática , Humanos , Inmunoglobulina G/química , Inmunohistoquímica , Cinética , Ratones , Ratones Endogámicos BALB C , Microscopía Fluorescente , Mucina-1/metabolismo , Péptidos/química , Unión Proteica , Estructura Terciaria de Proteína , Factores de Tiempo
8.
Hybrid Hybridomics ; 21(5): 375-9, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12470480

RESUMEN

Mouse-mouse hybridoma cell lines producing stable, highly specific and with good affinity monoclonal antibody (MAb) against the cardiac glycoside digoxin were established. Balb/c mice were immunized via injection of digoxin-3'-bovine serum albumin (BSA). The spleens of which were fused with myeloma cells of SP2/0 origin. Three clones designated as BBA, MBE, and BMG producing good antibodies displayed different patterns of fine specificity for digoxin and low cross-reaction with several digoxin analogues as elucidated by inhibition enzyme-linked immunosorbant assay (ELISA). All three MAbs were of the same class and subclass (IgG(1)). Affinity purification was performed for the selected clone BBA displaying the highest affinity and nearly no cross-reactivity with any of the structurally related molecules. Ultrafiltered concentrated hybrid cell supernatant was also purified by polyethylene glycol (PEG) 6000 precipitation for large-scale preparation and coated onto the wells of microtiter plates. The standard curve was constructed with a sensitivity of 10 pg/well covering up to 10 ng/well.


Asunto(s)
Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/inmunología , Digoxina/química , Digoxina/inmunología , Animales , Anticuerpos Monoclonales/aislamiento & purificación , Línea Celular , Relación Dosis-Respuesta a Droga , Ensayo de Inmunoadsorción Enzimática , Hibridomas , Cinética , Ratones , Ratones Endogámicos BALB C , Polietilenglicoles/farmacología , Unión Proteica , Albúmina Sérica/farmacología , Bazo/metabolismo
9.
J Immunoassay Immunochem ; 23(3): 385-98, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12227422

RESUMEN

The influence of various additives, such as organic solvents, polyhydric alcohols, salts, polymers, and cross-linker, on the stability and storage ability of penicillinase-morphine conjugate was studied in liquid and solid (freeze dried) states. The results of these experiments showed that using low concentrations of CaCl2 (0.1-0.2%) could stabilize enzyme activity in both states for more than seven months. The immunoreactivity of antigen toward the antibody did not change significantly. However, a cross-linker such as glutaraldehyde and various additives such as dimethylsulfoxide, glycerol, polyethylene glycol, gelatin, dextran, ammonium sulfate, lactose, and sucrose did not have any effect on stability. In addition, it was found that the presence of lactose and sucrose in the lyophilization procedure gives a significant amount of protection to the enzyme, which could last for a period of seven months and preserve almost 95% of the enzyme activity, as well as immunoreactivity of the tracer molecule.


Asunto(s)
Inmunoconjugados , Técnicas para Inmunoenzimas/normas , Penicilinasa , Cloruro de Calcio/farmacología , Reactivos de Enlaces Cruzados/farmacología , Estabilidad de Enzimas/efectos de los fármacos , Haptenos/inmunología , Inmunoconjugados/efectos de los fármacos , Morfina/inmunología , Conservadores Farmacéuticos/farmacología , Temperatura
10.
Hybridoma ; 19(5): 413-7, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11128031

RESUMEN

A C6-hemisuccinate derivative of morphine was prepared and conjugated to bovine serum albumin. High titer antibody producing spleen cells were removed and fused with myeloma cells of Sp2/0 origin. A C3-hemisuccinate derivative of morphine was prepared and conjugated to enzyme penicillinase used as a tracer molecule. A novel enzyme-linked immunoadsorbent assay was developed using this conjugate to screen and characterize the monoclonal antibody produced in these experiments. After two successive limiting dilutions, antibodies produced by 5 clones with good affinities ranging from 10(8) to 10(12) M(-1) and less cross-reaction (least for codeine and other structurally related molecules) were selected. These clones were found to be of IgG class with kappa light chain. Subclass determination showed that two of the clones produced IgG2b and three of them produced IgG1 type of antibody. Affinity purifications were performed for the selected clone (MOR-I). Purified antibody was coated onto the wells of microtiter plate. The standard curve was constructed with a sensitivity of 100 pg/mL covering up to 10 ng/mL in buffer and urine. The slope of the standard curve for selected clone in buffer and urine was calculated to be -0.7 and -0.64, respectively.


Asunto(s)
Anticuerpos Monoclonales/biosíntesis , Anticuerpos Monoclonales/inmunología , Afinidad de Anticuerpos , Especificidad de Anticuerpos , Morfina/inmunología , Animales , Ensayo de Inmunoadsorción Enzimática , Femenino , Hibridomas/inmunología , Inmunización , Ratones , Ratones Endogámicos BALB C
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