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1.
J Dairy Sci ; 97(4): 2193-203, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24565325

RESUMO

Suppression of cyclic activity in cattle is often desired in alpine farming and for feedlot cattle not intended for breeding. A cattle-specific anti-GnRH vaccination (Bopriva, Zoetis Australia Ltd., West Ryde, Australia) is approved for use in heifers and bulls in New Zealand, Australia, Mexico, Brazil, Argentina, Turkey, and Peru. Eleven healthy, cyclic Swiss Fleckvieh cows were included in the study and vaccinated twice with Bopriva 4wk apart. Injection site, rectal body temperature, and heart and respiratory rates were recorded before and 3d following each vaccination. Blood samples were taken weekly for progesterone and estrogen analysis and to determine GnRH antibody titer. Ovaries were examined weekly, using ultrasound to count the number of follicles and identify the presence of a corpus luteum. Thirty weeks after the first vaccination, the cows were subjected to a controlled internal drug-releasing device-based Select-Synch treatment. The GnRH antibody titers increased after the second vaccination and peaked 2wk later. Estrogen levels were not influenced by vaccination, and progesterone level decreased in 7 of 11 cows up to 3wk after the second vaccination and remained low for 10 to 15wk following the second vaccination. The number of class I follicles (diameter ≤5mm) was not influenced by vaccination, whereas the number of class II follicles (diameter 6-9mm) decreased between 7 and 16wk after the first vaccination. Class III follicles (diameter >9mm) were totally absent during this period in most cows. The median period until recurrence of class III follicles was 78d from the day of the second vaccination (95% confidence interval: 60-92d). After vaccination, all cows showed swelling and pain at the injection site, and these reactions subsided within 2wk. Body temperature and heart and respiratory rates increased after the first and second vaccinations and returned to normal values within 2d of each vaccination. The cows in our study were not observed to display estrus behavior until 30wk after the first vaccination. Therefore, a Select-Synch protocol was initiated at that time. Ten cows became pregnant after the first insemination (the remaining cow was reinseminated once until confirmed pregnancy). Bopriva induced a reliable and reversible suppression of reproductive cyclicity for more than 2mo. The best practical predictor for the length of the anestrus period was the absence of class III follicles.


Assuntos
Anestro/efeitos dos fármacos , Bovinos/fisiologia , Estrogênios/sangue , Hormônio Liberador de Gonadotropina/farmacologia , Progesterona/sangue , Vacinação/veterinária , Animais , Anticorpos/sangue , Bovinos/imunologia , Feminino , Gravidez
2.
Meat Sci ; 126: 36-42, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28006701

RESUMO

The objective of this study was to evaluate the effect of the GnRH vaccine on the performance and meat quality of Holstein bulls fed high concentrate diets. A total of 493 approximately 7month old bulls (initial BW 298±1.2kg) were allocated into 3 treatment groups, intact bulls (n=164), animals surgically castrated at 15 to 17d of the study (n=164), and animals vaccinated on 0 and 28d of the study with the GnRH vaccine (n=165). Animals were slaughtered between 131 and 133d and carcass quality was evaluated. Hot carcass weight, dressing percentage, fat classification and meat quality parameters did not differ significantly between surgically castrated and vaccinated animals but differed (P<0.05) from intact bulls. Carcass classification, pH at 26h, and fat color were not affected by treatment.


Assuntos
Ração Animal/análise , Qualidade dos Alimentos , Carne Vermelha , Vacinas Anticoncepcionais/administração & dosagem , Fenômenos Fisiológicos da Nutrição Animal , Animais , Composição Corporal , Bovinos , Dieta/veterinária , Relação Dose-Resposta a Droga , Hormônio Liberador de Gonadotropina/administração & dosagem , Concentração de Íons de Hidrogênio , Modelos Lineares , Masculino , Orquiectomia/veterinária , Vacinação/veterinária
3.
J Anim Sci ; 93(4): 1581-91, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26020180

RESUMO

Angus crossbred bulls (n = 60; 257 ± 5.4 d of age; initial BW 358.8 ± 3.78 kg) were used to study the effect of a vaccine against gonadotropin-releasing factor (GnRF) and band castration on behavioral and physiological indicators of pain. Cattle were randomly assigned to 1 of 3 treatments: bulls, band-castrated calves without pain mitigation (castrated), and immune-vaccinated animals administered an anti-GnRF vaccine (vaccinated). All animals were fitted with a radio frequency ear tag so that individual animal feed intake and feeding behavior were recorded daily over the entire trial using an electronic feed bunk monitoring system. Two doses of anti-GnRF vaccine were administrated on d -35 and 0 and band castration was performed on d 0. Animal BW was recorded weekly starting on d -36 until d 56. Visual analog scores (VAS) were measured on d -36 -35, -1, and 0, and salivary cortisol concentration was measured at -30, 0, 30, 60, 120, and 270 min on d -35 and 0 after castration. Saliva and blood were obtained on d 1, 2, 5, and 7 and weekly until d 56 for determination of cortisol and complete blood cell count. Video data were collected for pain, sexual, and aggressive behavior daily the first week and once a week until d 56. Data were analyzed with a mixed-effect model with castration, time, and their interactions as main effects. Vaccinated calves had reduced ADG and intake (P < 0.05 and P < 0.001, respectively) during the first week after vaccination. Band-castrated calves had reduced ADG and intake (P < 0.001) until the end of the study. No differences in salivary cortisol and VAS were observed among groups at d -35 after the first vaccination and before band castration. However, on d 0, castrated cattle had greater cortisol concentrations and VAS (P < 0.05 and P < 0.01, respectively) than bulls and vaccinated animals. Complete blood cell count did not differ (P > 0.05) between treatments on d 0, 1, and 2. At d 56, vaccinated calves had greater (P < 0.05) final BW than band-castrated calves and both had less final BW than bulls. There was no indication that vaccination caused any physiological or behavioral changes indicative of pain. In contrast, band castration resulted in elevated cortisol scores and VAS indicative of a pain response and behavior related to pain (P < 0.001) until d 42 of the study. The present study demonstrates that anti-GnRF vaccine is a viable animal welfare-friendly alternative to traditional band castration in beef cattle under North American feedlot practices.


Assuntos
Bem-Estar do Animal , Comportamento Animal/fisiologia , Bovinos/fisiologia , Comportamento Alimentar/fisiologia , Hormônio Liberador de Gonadotropina/imunologia , Orquiectomia/veterinária , Dor/veterinária , Vacinas Anticoncepcionais/efeitos adversos , Animais , Comportamento Animal/efeitos dos fármacos , Contagem de Células Sanguíneas , Temperatura Corporal , Comportamento Alimentar/efeitos dos fármacos , Hibridização Genética , Hidrocortisona/metabolismo , Incidência , Masculino , América do Norte , Orquiectomia/efeitos adversos , Orquiectomia/métodos , Dor/epidemiologia , Dor/etiologia , Saliva/metabolismo , Comportamento Sexual Animal/efeitos dos fármacos , Comportamento Sexual Animal/fisiologia , Vacinas Anticoncepcionais/farmacologia
4.
Clin Chim Acta ; 200(2-3): 191-9, 1991 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-1777968

RESUMO

A normal reference interval for serum amyloid P component (SAP) concentration in the serum was established in 500 healthy adult individuals (274 women, 226 men), by electroimmunoassay calibrated with standards of highly purified, isolated SAP. The mass of SAP in these was determined from the extinction coefficient of SAP at 280 nm measured here precisely for the first time by spectrophotometry and cryogenic drying. The mean (SD, range) SAP concentration was significantly lower in women: 24 mg/l (8, 8-55), compared to 32 mg/l (7, 12-50) in men (P less than 0.001). In renal insufficiency patients, 38 with chronic renal failure, 79 on hemodialysis and 66 on continuous ambulatory peritoneal dialysis, the mean values for SAP concentration were all significantly higher than normal (range of means, 39-59 mg/l in men and 35-42 mg/l in women), but did not correlate with serum creatinine, duration of dialysis or the presence of an acute phase response. The metabolism of SAP is thus altered in renal failure and is not normalized by dialysis, but it is not clear whether this is relevant to the pathogenesis of dialysis related arthropathy and amyloidosis.


Assuntos
Falência Renal Crônica/sangue , Diálise Peritoneal , Diálise Renal , Componente Amiloide P Sérico/análise , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fosfocreatina/sangue , Valores de Referência , Caracteres Sexuais , Espectrofotometria
5.
Meat Sci ; 95(1): 78-84, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23665362

RESUMO

Bos indicus bulls 20 months of age grazed on pasture in Minas Gerais, Brazil either received 2 doses of the GnRF vaccine Bopriva at d0 and d91 (group IC, n=144) or were surgically castrated on d91 (group SC, n=144). Slaughter on d280, was 27 weeks after castration. Adverse safety issues in 8% of group SC bulls following surgery contrasted with 0% in group IC bulls. At d105 testosterone levels were suppressed to similar levels in both groups. Importantly, group IC bulls had higher live weight, hot carcass weight, ADG (P<0.005) and dressing percentage (P<0.0001) compared to group SC animals. There were no negative effects on carcass or meat quality traits, thus immunocastration was concluded to offer a safe and effective method that provides production gains, and improves animal welfare in Bos indicus beef bulls without impacting meat and carcass quality.


Assuntos
Hormônio Liberador de Gonadotropina/imunologia , Carne/normas , Orquiectomia/veterinária , Vacinas/imunologia , Animais , Peso Corporal , Brasil , Bovinos/crescimento & desenvolvimento , Qualidade dos Alimentos , Masculino , Orquiectomia/métodos , Testículo/crescimento & desenvolvimento , Testículo/imunologia , Testosterona/sangue , Vacinação/veterinária
6.
Anim Reprod Sci ; 131(1-2): 72-80, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22440457

RESUMO

The aim of this study was to evaluate the effect of immunization against gonadotropin-releasing factor (GnRF) with Bopriva(®) (Pfizer Animal Health, Parkville, Australia) in prepubertal bull calves. For the study, 6 calves were vaccinated at the age of 3 and 6 weeks with 1 mL Bopriva(®), and 6 animals served as matched controls. Concentrations of GnRF antibodies, testosterone and LH were determined in serum samples out to 30 weeks after the first immunization. Body weight and scrotal circumference were measured for 59 weeks. At slaughter, 65 weeks after the first immunization, the quality of epididymal sperm was evaluated. The results showed that vaccination against GnRF influenced (P<0.05) anti-GnRF titer, LH and testosterone concentrations as well as scrotal circumference. Antibody titers significantly (P<0.05) increased after the booster vaccination and reached peak values 2 weeks later. Compared to control animals, inhibition (P<0.05) of the prepubertal LH secretion was observed in vaccinated calves at weeks 10 and 12-14 after the first vaccination. In vaccinated calves testosterone concentrations decreased after the booster injection to values below 0.5 ng/mL serum and remained for at least 22 weeks at this low level. Animals vaccinated with Bopriva(®) showed a delay in testes growth and smaller scrotal circumference. Puberty occurred at the age between 46 and 55 weeks in vaccinated and between 38 and 52 weeks in control animals and body weight gain was similar in both groups. All vaccinated bulls attained spermatogenic capacity at slaughter when they were 68 weeks old.


Assuntos
Bovinos/imunologia , Hormônio Liberador de Gonadotropina/imunologia , Vacinação/veterinária , Animais , Peso Corporal , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Hormônio Luteinizante/sangue , Masculino , Tamanho do Órgão , Distribuição Aleatória , Escroto/imunologia , Maturidade Sexual/fisiologia , Estatísticas não Paramétricas , Testículo/imunologia , Testosterona/sangue , Vacinação/métodos
7.
J Anim Sci ; 90(11): 3718-28, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22665672

RESUMO

The objective of this study was to determine the effects of a GnRH vaccine on feedlot performance and meat quality in Bos indicus Zebu × Brown Swiss bulls. The study was a 2 × 2 factorial arrangement of treatments with 1,600 bulls allocated by BW into 4 groups of ≈ 400 animals. The GnRH vaccine (Bopriva) was injected on d 0 and 42, and anabolic implants given on d 0 (Component E-S) and d 84 (Synovex Choice). Group designations were: Con = placebo control; Imp = implants alone; Vac = GnRH vaccine alone; and Vac+Imp = GnRH vaccine together with implants. The second GnRH vaccination at d 42 resulted in elevated titers of IgG antibody and suppressed concentrations of testosterone in vaccinated groups (Vac and Vac+Imp) at d 56 (P < 0.001), with titers and suppressed testosterone persisting to d 147 (P < 0.001). Groups Vac and Vac+Imp had reduced testes weights at slaughter on d 147 (P < 0.001). Bulls in group Vac were not different in final BW, HCW, or ADG (d 42 to 147) relative to bulls in group Con. Bulls in group Vac+Imp had greater final BW than bulls in group Imp (P = 0.008) and greater BW than bulls in group Vac and group Con (P < 0.001). The HCW of Vac+Imp bulls was greater than the Vac or Con bulls (P < 0.001) but was not different to the Imp bulls (P = 0.294). Improved ADG was obtained by vaccination with the GnRH vaccine, in the presence of implants (group Vac+Imp compared with group Imp, P < 0.001) or absence of implants (group Vac compared with group Con, P = 0.028). Meat quality of bulls receiving the GnRH vaccine was improved irrespective of implant status, with a 1.6- to 2.6-fold increase in the proportion of bulls in groups Vac and Vac+Imp, respectively, grading as USDA Choice (P < 0.002) and with greater fat depth at the 12th rib (P < 0.001). Meat tenderness was improved in the vaccine groups (Vac and Vac+Imp) compared with groups Con and Imp (P < 0.004). Use of the GnRH vaccine Bopriva in Bos indicus × Brown Swiss bulls finishing in a feedlot under Mexican husbandry conditions can provide improved performance in combination with implants (increased BW and ADG) and improved meat quality, with or without implants, and in particular, better USDA carcass grading and loin fat cover.


Assuntos
Hormônio Liberador de Gonadotropina/imunologia , Carne/normas , Orquiectomia/veterinária , Vacinas/imunologia , Animais , Peso Corporal , Bovinos/crescimento & desenvolvimento , Masculino , Orquiectomia/métodos , Testículo/crescimento & desenvolvimento , Vacinação/veterinária
8.
Theriogenology ; 78(1): 182-8, 2012 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-22541323

RESUMO

The aim of this study was to evaluate the effects of vaccination against gonadotropin-releasing factor (GnRF) on testicular development, testosterone secretion, and physical activity in pubertal bulls. The experiment was performed using 44 bulls aged between 6 and 7 mo. Twenty-three animals were vaccinated twice 4 wk apart with 1 mL of Bopriva (Pfizer, Animal Health, Parkville, Australia) and 21 bulls served as matched controls. Serum GnRF antibody titer and testosterone concentration as well as body weight and scrotal circumference were determined in all bulls for 24 wk from the first vaccination. In addition, physical activity was analyzed in 11 vaccinated and in 10 control animals using the ALPRO DeLaval activity meter system (DeLaval AG, Sursee, Switzerland). The results show that vaccination significantly (P < 0.05) influenced all parameters evaluated except body weight. Antibody titers to GnRF began to rise 2 wk after the first vaccination and reached peak values 2 wk after the second injection. Significant group differences in anti-GnRF titer were present for 22 wk following the first vaccination. Testosterone concentrations were significantly lower between weeks 6 to 24 after first vaccination in bulls with Bopriva compared with control animals. In vaccinated bulls testicular development was impaired after the second injection and scrotal circumference was significantly smaller between weeks 8 to 24 after first vaccination. Physical activity of vaccinated bulls was reduced after the booster injection with significant group differences for a continuous period of 106 days. In conclusion, vaccination against GnRF with Bopriva in pubertal bulls decreased testosterone levels in peripheral blood, testicular development, and physical activity but did not affect weight gain.


Assuntos
Bovinos , Hormônio Liberador de Gonadotropina/imunologia , Atividade Motora/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testosterona/sangue , Vacinas Anticoncepcionais/farmacologia , Animais , Anticorpos/análise , Anticorpos/sangue , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Escroto/efeitos dos fármacos , Escroto/crescimento & desenvolvimento , Maturidade Sexual/efeitos dos fármacos , Maturidade Sexual/fisiologia , Testículo/crescimento & desenvolvimento , Vacinação/veterinária
9.
Proteins ; 12(1): 91-9, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1553384

RESUMO

Hexagonal crystals of turkey egg white lysozyme have been examined for activity in order to evaluate their potential for use in time-resolved X-ray crystallographic experiments. Substrates used in this study were hexa-N-acetylglucosamine (hexa-GlcNAc) and a modified analogue of hexa-GlcNAc where the terminal sugar ring was opened by reduction with tritiated sodium borohydride. This gave a labeled beta-N-acetylglucosaminitol unit at the sixth position of the sugar chain and allowed easy quantitation of enzymatic cleavage on TLC plates. Using these substrates, it has been shown that turkey egg white lysozyme is enzymatically active in the crystal. Enzyme dispersed in the buffer surrounding the crystal does not show detectable activity under conditions relevant to an X-ray experiment. Unmodified hexa-GlcNAc is hydrolyzed into di-, tri-, and tetrasaccharides in the crystal. This cleavage pattern is different from that obtained with hen egg white lysozyme in solution and likely causes of the differences are discussed. The reduced radiolabeled oligosaccharide has a unique cleavage pattern with trisaccharides as the products. The specific activity of the enzyme with the radiolabelled analogue was 9.8 (+/- 1.0) x 10(-7) mmol/min/mg protein at 22 degrees C in the crystal.


Assuntos
Clara de Ovo , Muramidase/metabolismo , Animais , Sequência de Carboidratos , Cromatografia em Camada Fina , Cristalização , Dados de Sequência Molecular , Muramidase/química , Especificidade por Substrato , Perus , Difração de Raios X
10.
Eur J Biochem ; 214(1): 99-110, 1993 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-8508812

RESUMO

The N-linked oligosaccharides of C-reactive protein (CRP) from the arachnid Limulus polyphemus, the horseshoe crab, were characterized after their release by hydrazinolysis, re-N-acetylation, and reduction with NaB3H4. High-voltage paper electrophoresis of the reduced oligosaccharides revealed only neutral species. Gel-permeation chromatography on Bio-Gel P4 yielded five fractions. The oligosaccharide fractions were further fractionated using high-voltage borate paper electrophoresis and Dionex BioLC ion-exchange chromatography. The oligosaccharides were structurally characterized by sequential exoglycosidase digestion, fragmentation by acetolysis and methylation analysis. Three major structures were found, of which two were the biantennary oligomannose type with compositions Man5GlcNAc2 (B-1), Man4GlcNAc2 (C-3) and one was the monoantennary structure Man3GlcNAc2 (D-1). The biantennary oligomannose structures B-1 and C-3 contained the structural unit Man alpha 6Man alpha 6R. This unusual arrangement of mannose linkages suggests a biosynthetic pathway in Limulus which differs from that reported in mammals, plants and the parasitic protozoa.


Assuntos
Asparagina/química , Proteína C-Reativa/química , Caranguejos Ferradura/química , Oligossacarídeos/química , Animais , Sítios de Ligação , Proteína C-Reativa/isolamento & purificação , Configuração de Carboidratos , Sequência de Carboidratos , Cromatografia em Gel , Cromatografia por Troca Iônica , Eletroforese , Manosidases/metabolismo , Metilação , Dados de Sequência Molecular , Oligossacarídeos/isolamento & purificação
11.
J Biol Chem ; 269(44): 27687-91, 1994 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-7961688

RESUMO

Transforming growth factor-beta 1 (TGF-beta 1) is a homodimeric protein stabilized by a single disulfide bridge between Cys77 on the respective monomers and two paired complementary hydrophobic interfaces between the two subunits. A TGF-beta 1 mutant with Cys77 replaced by serine has been expressed in stably transfected Chinese hamster ovary cells and purified to homogeneity. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis confirms that the sole interchain disulfide bond in TGF-beta 1 has been eliminated. It is 20% as potent as native TGF-beta 1 in the induction of plasminogen activator inhibitor-1 promoter expression in mink lung epithelial cells (Mv1Lu), although it is less than 1% as potent as native TGF-beta 1 in inhibition of growth in the same cell line. The mutant acts as a full agonist in both bioassays. [Ser77]TGF-beta 1 binds to soluble type II receptors and competes with native TGF-beta 1 in sandwich-enzyme-linked immunosorbent assays; however, in Mv1Lu cells, the mutant shows preferential cross-linking to type I rather than type II receptors. [Ser77]TGF-beta 1 is a useful tool for understanding the different ligand-receptor complexes and numerous biological activities of this multifunctional cytokine.


Assuntos
Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Fator de Crescimento Transformador beta/química , Animais , Bioensaio , Células CHO , Linhagem Celular , Cricetinae , Cisteína/química , Dissulfetos/química , Técnicas In Vitro , Camundongos , Vison , Modelos Moleculares , Mutagênese Sítio-Dirigida , Conformação Proteica , Proteínas Recombinantes , Serina/química , Relação Estrutura-Atividade
12.
Biochem J ; 299 ( Pt 1): 261-75, 1994 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-8166649

RESUMO

The primary structures of the N-linked oligosaccharides from normal human serum IgA1 were determined by a combination of sequential exoglycosidase digestion, Bio-Gel P-4 chromatography, anion-exchange chromatography and one-dimensional n.m.r. spectroscopy. Three major N-linked disialylated biantennary-complex-type structures were found (55%). The remaining N-linked oligosaccharides consisted of at least nine further structures, some of which (7%) were of the triantennary type and included disialylated triantennary oligosaccharides with outer-arm fucose substitution [Fuc alpha 1-3(4)]. Compared with IgG, the N-glycan structures on IgA are more completely processed: the outer arms have a higher proportion of galactose and sialic acid, and only trace levels of incompletely galactosylated oligosaccharides, commonly found on IgG, were detected. Analysis of the sialylated O-glycans revealed that 64% were [NeuAc2 alpha 3(6)]2Gal beta 3GalNAc and 9% were [NeuAc2 alpha 3(6)]-Gal beta 4GlcNAc beta 6[NeuAc2 alpha 3(6)Gal beta 3]GalNAc, and 27% were monosialylated. The N-linked glycosylation of both serum IgA1 and IgG isolated from a group of six normal individuals was compared with that from ten patients with rheumatoid arthritis (RA). In contrast with the hypogalactosylation found in IgG from diseased sera, there was no evidence of an equivalent decrease in the galactosylation of the IgA1 oligosaccharides. In addition, the N-glycosylation of IgA1 was remarkably consistent within the group of normal individuals. These data suggest that incomplete galactosylation of N-linked glycans and its augmentation in RA does not extend to IgA1 and that the RA-associated galactosyltransferase deficiency may be restricted to cells producing gamma-chain.


Assuntos
Artrite Reumatoide/imunologia , Imunoglobulina A/química , Polissacarídeos/química , Configuração de Carboidratos , Sequência de Carboidratos , Cromatografia em Gel , Eletroforese em Gel de Poliacrilamida , Galactose/análise , Humanos , Imunoglobulina A/metabolismo , Imunoglobulina G/química , Imunoglobulina G/metabolismo , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Polissacarídeos/metabolismo , Ácidos Siálicos/química
13.
Proc Natl Acad Sci U S A ; 90(18): 8628-32, 1993 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-7690965

RESUMO

Three distinct isoforms of transforming growth factor beta (TGF-beta) are expressed in mammalian cells. Although many cells respond equivalently to all three isoforms, certain cells respond selectively. Using chimeric proteins in which selected regions of the different isoforms were interchanged, we have identified two distinct functional domains of TGF-beta involved in determining the biological potencies and functions of the molecule. The first domain is important for determining whether TGF-beta can be sequestered by alpha 2-macroglobulin. By replacing aa 45 and 47 of TGF-beta 2 with the corresponding amino acids of TGF-beta 1, sequestration of the TGF-beta molecule by alpha 2-macroglobulin was markedly reduced. The second domain is functionally different from the alpha 2-macroglobulin sequestration site and is important for determining the potency of TGF-beta to inhibit growth of the LS513 human colorectal cancer cell line. Neither the TGF-beta 2/beta 1-(40-47) replacement construct nor a chimera containing aa 1-39 of TGF-beta 2, aa 40-82 of TGF-beta 1, and aa 83-112 of TGF-beta 2 was equivalent to TGF-beta 1 in inhibiting growth of LS513 cells. This fact suggests that additional amino acids outside of the aa 40-82 region are required to specify TGF-beta 1 activity with these cells.


Assuntos
Endotélio Vascular/citologia , Fator de Crescimento Transformador beta/farmacologia , Células 3T3 , Sequência de Aminoácidos , Animais , Células CHO , Bovinos , Cricetinae , Relação Dose-Resposta a Droga , Endotélio Vascular/efeitos dos fármacos , Coração , Humanos , Cinética , Camundongos , Dados de Sequência Molecular , Receptores de Superfície Celular/efeitos dos fármacos , Receptores de Superfície Celular/metabolismo , Receptores de Fatores de Crescimento Transformadores beta , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/farmacologia , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/farmacologia , Fator de Crescimento Transformador beta/biossíntese , Fator de Crescimento Transformador beta/isolamento & purificação , Veias Umbilicais , alfa-Macroglobulinas/farmacologia
14.
Proc Natl Acad Sci U S A ; 91(12): 5602-6, 1994 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-8202534

RESUMO

Human serum amyloid P component (SAP) is a normal plasma protein and the precursor of amyloid P component (AP), a universal constituent of the abnormal tissue deposits in amyloidosis, including Alzheimer disease. We show here that its single N-linked biantennary oligosaccharide does not display the microheterogeneity usually characteristic of glycoproteins. The protein and the glycan structures of AP were also invariant, their resistance to degradation suggesting a role in persistence of amyloid deposits. Asialo-SAP was rapidly cleared from the circulation in mice by a mechanism dependent on terminal galactose residues and was catabolized in hepatocytes. However blockade of this pathway did not affect the clearance of native SAP. Rapid hepatic uptake and catabolism of human asialo-SAP in man were also directly demonstrated. The protein and glycan homogeneity of SAP and the integrity of AP suggest that the complete glycoprotein structure is important for the normal and the pathophysiological functions of this molecule.


Assuntos
Amiloide/química , Componente Amiloide P Sérico/química , Animais , Assialoglicoproteínas/metabolismo , Sequência de Carboidratos , Feminino , Humanos , Taxa de Depuração Metabólica , Camundongos , Camundongos Endogâmicos CBA , Dados de Sequência Molecular , Componente Amiloide P Sérico/metabolismo
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