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1.
The effect of the somatomedin-/insulin-like growth factors IGF-I, IGF-II and N2, as well as of semi-purified SM fractions separated by isoelectric focusing derived from human Cohn IV on different growth parameters, have been studied in the Snell dwarf mouse. HPLC-pure IGF-II, N2 and IGF-I stimulate to a similar extent the sulphate incorporation into costal cartilage, the osteochondral junction and epiphyseal cartilage. After 4 weeks of treatment, increase in body length and weight as well as the weights of several organs is obtained with SM fractions, focusing at acid and neutral pH, and containing mainly IGF-II- and less than 5% IGF-I-like peptides. Fractions containing mainly IGF-I-like peptides and focusing at basic pH at the dosage used seem to be less stimulatory on most of these parameters. The rump/tail ratio and weight/length ratio is comparable to that obtained after treatment with human growth hormone (hGH). hGH induced a significant stimulation of the weight of the liver, kidneys, heart, thymus and spleen. The acid and neutral SM fractions induced growth of the liver, kidneys and spleen. The basic fractions only produced a significant weight gain in kidneys and spleen. The skinfold thickness is stimulated by the SM preparations and only slightly by hGH.  相似文献   

2.
Non-adherent bone marrow cells of a bled rabbit were cultured in plasma clot media containing auto-serum, alpha-medium, erythropoietin (Ep) and spleen extract from irradiated rats. The preparations were cloted on a cover glass, fixed and stained by Giemsa or hemoglobin staining method after 3 or 5 days in culture, and the number of erythroid colony was counted as reported elsewhere. In the present study, first, it was elucidated that the optimal numbers of innoculating cells were among 0.6 approximately 1.2 x 10(4) cells per well for the erythroid colony formation. Second, this colony formation was slightly stimulated by the experimental media which contained heat treated extract at 40 degree or 50 degree C for 30 minutes. Contrary this, the extract treated at 70 degree C for 30 minutes lost completely its stimulating activity of the colony formation, suggesting that the effective substances might be protein in the extract. Third, an inhibitory factory might be present in the dialysate of the crude spleen extract, because the number of erythroid colonies decreased in a dose response manner by the dialysate. The residue of inner dialysate, however, certainly contained the colony stimulating factors (s). The crude extract was separated into five fractions (F1 approximately F5) by ammonium sulfate. F1, which was precipitated with 40% ammonium sulfate, had the highest activity for the colony formation. Fetuin also showed appreciable effect on the erythroid colony formation.  相似文献   

3.
Duox2 (and probably Duox1) is a glycoflavoprotein involved in thyroid hormone biosynthesis, as the thyroid H2O2 generator functionally associated with Tpo (thyroperoxidase). So far, because of the impairment of maturation and of the targeting process, transfecting DUOX into nonthyroid cell lines has not led to the expression of a functional H2O2-generating system at the plasma membrane. For the first time, we investigated the H2O2-generating activity in the particulate fractions from DUOX2- and DUOX1-transfected HEK293 and Chinese hamster ovary cells. The particulate fractions of these cells stably or transiently transfected with human or porcine DUOX cDNA demonstrate a functional NADPH/Ca2+-dependent H2O2-generating activity. The immature Duox proteins had less activity than pig thyrocyte particulate fractions, and their activity depended on their primary structures. Human Duox2 seemed to be more active than human Duox1 but only half as active as its porcine counterpart. TPO co-transfection produced a slight increase in the enzymatic activity, whereas p22(phox), the 22-kDa subunit of the leukocyte NADPH oxidase, had no effect. In previous studies on the mechanism of H2O2 formation, it was shown that mature thyroid NADPH oxidase does not release O2*- but H2O2. Using a spin-trapping technique combined with electron paramagnetic resonance spectroscopy, we confirmed this result but also demonstrated that the partially glycosylated form of Duox2, located in the endoplasmic reticulum, generates superoxide in a calcium-dependent manner. These results suggest that post-translational modifications during the maturation process of Duox2 could be implicated in the mechanism of H2O2 formation by favoring intramolecular superoxide dismutation.  相似文献   

4.
Using the solid-phase procedure an analog of trypsin inhibitor CMTI III containing Val5 instead of Arg5 in position P1, was synthesized. The substitution in only this one position P1 increased the affinity of synthetic inhibitor to porcine pancreatic elastase and human leukocyte elastase by the factor of 10(3) and 10(7), respectively.  相似文献   

5.
Studies were made on whether sera from various animals or serum components could induce in vitro maturation of medaka oocytes in the absence of any exogenous hormone. When intra-follicular oocytes were preincubated in medium containing serum of some mammals or chickens, and were then washed, they matured during further incubation in the same medium without the serum. In contrast, no remarkable stimulatory effect on oocyte maturation was recognized in sera from some other mammals and from reptiles, amphibian and fish. A dialysate of rabbit serum collected using a cellulose membrane (mol. wt. retention 3,500) also induced in vitro maturation of intra-follicular oocytes. This activity was stable on treatment with proteolytic enzymes or heat-treatment. Small molecular weight fractions with this activity were obtained by filtering the dialysate through Sephadex G-10. The oocytes matured by the serum factor were capable of developing normally beyond the stage of embryonic body formation.
From these results, it is concluded that the serum of higher vertebrates contains a low molecular weight factor that stimulates in vitro nuclear and cytoplasmic maturation of intrafollicular fish oocytes.  相似文献   

6.
Four mouse monoclonal IgG1 antibody-producing cell lines (5LO-1, 5LO-2, 5LO-3, 5LO-4), produced against highly purified human leukocyte 5-lipoxygenase have been characterized. The monoclonal antibodies produced by these cell lines exhibited differential reactivity against 5-lipoxygenase as determined by ELISA and immunoprecipitation analyses. Monoclonal antibodies 5LO-2 and 5LO-3 inhibited the activity of recombinant human leukocyte 5-lipoxygenase in a dose-dependent manner. This inhibition was selective for 5-lipoxygenase activity since these monoclonal antibodies did not inhibit human leukocyte 15-lipoxygenase or porcine leukocyte 12-lipoxygenase.  相似文献   

7.
P M Grob  K C Chadha 《Biochemistry》1979,18(26):5782-5786
Human leukocyte interferon (HL-IF), produced by mixed leukocytes infected with Newcastle disease virus, was resolved into three distinct fractions when chromatographed on concanavalin A-agarose. The major portion (70--75%) of interferon appeared in the breakthrough (BT fraction). The bound interferon (25--30%) was displaced from the column as two peaks: the first was eluted with 0.01 M methyl alpha-D-mannoside, yielding 15-20% of the interferon activity (alpha-MM fraction), and the second by including ethylene glycol (70%) in the eluant, yielding the remaining 5--15% of the interferon (EG fraction). No interferon was retained when HL-IF produced in the presence of glycosylation inhibitors (tunicamycin or 2-deoxy-D-glucose) was chromatographed on concanavalin A-agarose, suggesting that the fraction of interferon retained by this lectin is glycosylated. The three fractions of interferon (BT, alpha-MM, and EG) were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, cross-species antiviral activity, and neutralization by specific antisera. The BT fraction contains exclusively the 16 000 molecular weight component of human leukocyte interferon. The majority of the alpha-MM fraction (90%) is the 21 000 molecular weight component. However, the EG fraction contains the 16 000 and 21 000--23 000 molecular weight components in essentially equal proportions. On the basis of cross-species antiviral activity and neutralization by specific antisera, the BT and alpha-MM fractions are leukocyte-type interferon and the EG fraction seems to be primarily of fibroblast type.  相似文献   

8.
Type III glycogen storage disease is caused by a deficiency of glycogen debranching-enzyme activity. Many patients with this disease have both liver and muscle involvement, whereas others have only liver involvement without clinical or laboratory evidence of myopathy. To improve our understanding of the molecular basis of the disease, debranching enzyme was purified 238-fold from porcine skeletal muscle. In sodium dodecyl sulfate-polyacrylamide gel electrophoresis the purified enzyme gave a single band with a relative molecular weight of 160,000 that migrated to the same position as purified rabbit-muscle debranching enzyme. Antiserum against porcine debranching enzyme was prepared in rabbit. The antiserum reacted against porcine debranching enzyme with a single precipitin line and demonstrated a reaction having complete identity to those of both the enzyme present in crude muscle and the enzyme present in liver extracts. Incubation of antiserum with purified porcine debranching enzyme inhibited almost all enzyme activity, whereas such treatment with preimmune serum had little effect. The antiserum also inhibited debranching-enzyme activity in crude liver extracts from both pigs and humans to the same extent as was observed in muscle. Immunoblot analysis probed with anti-porcine-muscle debranching-enzyme antiserum showed that the antiserum can detect debranching enzyme in both human muscle and human liver. The bands detected in human samples by the antiserum were the same size as the one detected in porcine muscle. Five patients with Type III and six patients with other types of glycogen storage disease were subjected to immunoblot analysis. Although anti-porcine antiserum detected specific bands in all liver and muscle samples from patients with other types of glycogen storage disease (Types I, II, and IX), the antiserum detected no cross-reactive material in any of the liver or muscle samples from patients with Type III glycogen storage disease. These data indicate (1) immunochemical similarity of debranching enzyme in liver and muscle and (2) that deficiency of debranching-enzyme activity in Type III glycogen storage disease is due to absence of debrancher protein in the patients that we studied.  相似文献   

9.
A recently published method for preparation of porcine growth hormone resulted in a highly purified protein with good biological activity. However, after storing for some months the originally homogeneous hormone separated again into several fractions when rechromatographed on ion exchange columns. The biological activity, found in one of these fractions, was clearly diminished compared with the activity of a freshly prepared hormone. In the present paper a modified procedure is described for the isolation of a more stable porcine growth hormone. The influence of ions, involved in buffers of the same molarity and the same pH, upon ion exchange chromatography of porcine growth hormone is discussed. The purified hormone shows high biological activity in the tibia test and is free of activities of other pituitary hormones. The molecular weight is about 20 000; only phenylalanine is found as N-terminal as well as C-terminal amino acid; the amino acid composition resembles neither that of porcine growth hormone described in literature nor that of human growth hormone.  相似文献   

10.
Partial purification of cyclic AMP-binding proteins from porcine thyroid cytosol was performed by gel filtration on Bio Gel 1.5 m followed by ion exchange chromatography on DEAE Sephadex A25. Three fractions presenting cyclic AMP-binding activities were resolved by gel filtration (I, II, III). Approximate molecular weights were respectively 280 000, 145 000 and 65 000. Fraction I was further resolved into two peaks (Ialpha and Ibeta) on DEAE-Sephadex A25. Fractions I, Ialpha, Ibeta comigrated with protein kinase activity whereas peaks II and III did not. These fractions differed with respect to the folling characteristics: rate and stability of cyclic AMP binding to isolated fractions were differently affected by pH (4.0 or 7.5). Electrophoretic mobility on polyacrylamide gels (5%) of fractions preincubated with cyclic [3H]AMP showed similar mobilities for Ialpha, Ibeta or II (Rf 0.37) whereas fraction III displayed a much greater mobility (RF 0.73); Scatchard plots were linear for fractions Ialpha, II and III with an apparent Kd in the same range (2 to 5 nM) whereas fraction Ibeta generated a biphasic plot with Kd 0.4 nM and 20 nM; cyclic [3H] AMP added to fraction I, Ialpha or Ibeta generated a cyclic [3H] AMP-binding protein complex of lower molecular weight as shown by Sephadex G 150 filtration; on the basis of the elution volume, this complex was not distinguished from fraction II. In the course of this work, we separated at the first step of purification (Bio Gel 1.5 m) a protein kinase not associated with cyclic AMP binding activity which exhibited marked specificity for protamine as compared to histone II A.  相似文献   

11.
An extract of porcine brain acetone powder incubated with thyrotropin-releasing hormone (TRH; pGlu-His-ProNH2) produces acid TRH (pGlu-His-Pro), histidine, and prolineamide. Fractionation of the brain extract by DEAE-cellulose chromatography produces three protein fractions which metabolize TRH. The activity of these fractions was characterized using TRH with a 3H-label on the histidine or proline as well as [His-3H]His-ProNH2. Fraction I contains pyroglutamate aminopeptidase and Fraction II contains TRH deamidase. Fraction III was found to contain a previously unrecognized enzyme which cleaves His-ProNH2 to histidine and proline. The histidylprolineamide imidopeptidase has been characterized. A competition study using a variety of compounds containing histidine or proline suggests that the best substrates for the imidopeptidase contain a free alpha-amino group on histidine and a blocked carboxyl group on proline, as is found in His-ProNH2. A survey of a variety of polypeptide hormones indicates that many of them inhibit the imidopeptidase activity. A kinetic study of the inhibition of the enzyme by adrenocorticotropic hormone (1-24) shows that the inhibition by polypeptide hormones is noncompetitive. We hypothesize that pituitary hormones may stimulate the production of (cyclo)-His-Pro by inhibiting alternate routes of TRH metabolism.  相似文献   

12.
We have studied in vitro the effects of leukocyte dialysates containing transfer factor on the formation of sheep cell rosettes by human lymphocytes. Dialysate had no effect on the toral rosettes, but increased the number of rapidly forming ("active") rosettes. This was due to an increased affinity of the lymphocytes for the sheep red cell. Trypsin-treated lymphocytes regained the ability to form rosettes more rapidly when cultured with leukocyte dialysates than with control media. These experiments suggest that leukocyte dialysate acts to increase the number or arrangement of sheep cell receptors on the lymphocyte surface.  相似文献   

13.
The effect of antigen-induced stimulation on acid deoxyribonuclease (DNase) activity in BALB/c mouse lymphoid cells was determined. Increase in acid DNase activity was found in intact spleen cell populations of mice from the second or fourth day after immunization with pneumococcal polysaccharide type III and from the fourth day after immunization with SRBC. DNase determinations performed with spleen cell fractions prepared from SRBC-immunized mice, showed that the rise in the enzyme activity was confined to the fraction containing the antibody-forming cells. The DNase activity was also increased in spleen cell cultures, stimulated with SRBC in vitro. Rise in the activity of this enzyme was also observed in peritoneal cell populations taken from SRBC-immunized mice. This change was maximal on the second day after immunization, when no appreciable increase in DNase activity of spleen cells was yet detected. The results obtained suggest, that acid DNase is an enzyme involved in the proliferative/maturation response to antigenic stimulation. It is a consequence of antigenic stimulation rather than being involved in the process of afferent stimulation.  相似文献   

14.
It has been proposed on the basis of amino acid sequence homology that the leukocyte common antigen CD45 represents a family of catalytically active, receptor-linked protein tyrosine phosphatases [Charbonneau, H., Tonks, N. K., Walsh, K. A., & Fischer, E. H. (1988) Proc. Natl. Acad. Sci. U.S.A. 85, 7182-7186]. The present study confirms that CD45 possesses intrinsic protein tyrosine phosphatase (PTPase) activity. First, a mouse monoclonal antibody to CD45 (mAb 9.4) specifically eliminated, by precipitation, PTPase activity from a high Mr fraction containing CD45, prepared by gel filtration (Sephacryl S200) of a Triton X-100 extract of human spleen. Second, PTPase activity was demonstrated in a highly purified preparation of CD45 that was eluted with a high pH buffer from an affinity column, constructed from the same antibody. Third, on sucrose density gradient centrifugation, PTPase activity was only found in those fractions that contained CD45 as determined by Western analysis. When CD45 was caused to aggregate, first by reacting it with mAb 9.4 and then adding a secondary, cross-linking anti-mouse mAb, the PTPase activity shifted to the same higher Mr fractions that contained CD45. No shift in CD45 or PTPase was observed following addition of a control IgG2a. On this basis, it is concluded that CD45 is a protein tyrosine phosphatase.  相似文献   

15.
Immunomodulatory activity of an Ayurvedic polyherbal formulation, Immu-21 containing extracts of Ocimum sanctum, Withania somnifera, Emblica officinalis and Tinospora cordifolia was studied on proliferative response of splenic leukocytes to T cell mitogens, concanavalin (Con)-A and phytohemagglutinin (PHA) and B cell mitogen, lipopolysaccharide (LPS) in vitro by [3H]-thymidine uptake assay in mice. The cytotoxic activity of Immu-21 was tested by measuring the splenic leukocyte natural killer (NK) cell activity against K 562 cells. Intraperitoneal (i.p.) treatment with Immu-21 (30 mg/kg) once a day for 14 and 21 days did not cause change in body weight and spleen weight, where as splenocytes/spleen count was increased. Treatment of Immu-21 (30 mg/kg, i.p.) for 14 days and 1 mg/kg for 21 days significantly increased LPS induced leukocyte proliferation. NK cell activity was significantly increased when mice were pretreated with Immu-21 (10 and 30 mg/kg, i.p.) once a day for 7 days. The results indicate that pretreatment with Immu-21 selectively increased the proliferation of splenic leukocyte to B cell mitogen, LPS and cytotoxic activity against K 562 cells in mice.  相似文献   

16.
1. Human, porcine, rabbit, and rat antithrombin III have been purified by affinity chromatography using heparin-agarose. The amino acid and carbohydrate compositions, amino-terminal sequences, immunological cross-reactivities, and inhibitions of human thrombin were studied. 2. Human, porcine, rabbit, and rat antithrombin III are single-chain glycoproteins containing hexose, glucosamine, and neuraminic acid. 3. The total carbohydrate contents were 17, 16, 14, and 15% for human, porcine, rabbit, and rat antithrombin III, respectively. 4. Molecular weights estimated from the migration in sodium dodecyl sulfate (SDS)-poly-acrylamide gel electrophoresis were 59,000, 58,000, 63,000, and 63,000 for human, porcine rabbit, and rat antithrombin III, respectively. 5. These four proteins have similar amino acid compositions, although some minor differences were noted. 6. Human, porcine, and rabbit antithrombin III have a histidine residue at the amino-terminus, while rat antithrombin III contains an amino-terminal asparagine residue. 7. The amino-terminal sequences up to the first 17 residues showed high homology among the four proteins. 8. Some immunological cross-reactivity was observed only between human and porcine antithrombin III. 9. The apparent dissociation constants (KI) for the complexes between human thrombin and human, porcine, rabbit, and rat antithrombin III were about 1.2 x 10(-10) M, 9.5 X 10 (-9) M, 1.4 X 10(-7) M, and 2.8 X 10(-9) M, respectively.  相似文献   

17.
Two glycosphingolipids with J blood group activity were found in J-positive bovine spleen. They were tentatively identified as ceramide deca- and dodecahexosides containing galactose, glucose, N-acetylgalactosamine and N-acetylglucosamine in a molar ratio of 5:3:1:1 and 6:3:2:1, respectively. Fucose was not present. Ceramide decahexosides without J activity were also found in J-negative bovine spleen. The principal component fatty acids of the J-active glycosphingolipids were saturated even-numbered long-chain acids with 16 to 24 C atoms. Their principal long-chain bases were sphingosine and dihydrosphingosine with smaller amounts of phytosphingosine. Both J-active glycosphingolipids were readily water-soluble and showed strong activity in the bovine J and in the porcine A blood group system. They exhibited no cross-reactivity in the human A system. However, a J-negative glycosphingolipid fraction - also from J-negative spleen - with shorter carbohydrate chain-length showed strong activity in the human A system.  相似文献   

18.
We report on the extension of the direct leukocyte migration inhibition (LMI) test as an assay for antigen-specific activity in human leukocyte dialysates (DLE) containing transfer factor to an evaluation of antigen-specific activity in DLE prepared from inbred mice. Murine DLE was observed to cause antigen-dependent and antigen-specific effects on the inhibition of migration of nonimmune human leukocyte populations. Pulsing of nonimmune human leukocyte with DLE preparations from BALB/c and SJL mice immunized with Candida, diphtheria toxoid, and SK-SD resulted in their inhibition of migration in the presence of the respective antigens. The antigen-specific activity in murine DLE was found to be present in lymph node cell preparations and to be absent from spleen cell preparations of the same donors. The activity of DLE in lymph node cells was found to be present in the theta-cell enriched subpopulation of nonadherent lymphocytes after passage through nylon wool columns. The antigen-specific activity of murine DLE, as we have reported for human DLE, was found to reside in the < 3500 dalton dialysis fraction and not in the < 3500 dalton fraction. We conclude that nonimmune human leukocytes in the LMI test provide a suitable assay for the detection of antigen-specific activity in murine DLE as well as that in human DLE. Additionally, murine DLE is active across species barriers and appears to share properties with human DLE.  相似文献   

19.
20.
通过对贵州万山汞污染地区及北京地区猪肝脏和肾脏组织上清液进行凝胶过滤色谱分离(SephadexG 10 0 ) ,随后用原子荧光法测定它们蛋白质组分中汞和硒的含量 ,研究在汞暴露水平不同状态下微量元素汞和硒在动物体蛋白质分子水平上的分布 .发现这两个地区猪肝脏和肾脏组织上清液蛋白质组分中汞和硒的分布模式有明显差异 .贵州万山汞污染地区猪肝脏上清液中汞浓度比北京地区高 ,硒浓度也相应高 ,且前者与高分子量和低分子量蛋白结合的硒均明显高于后者 ;而北京地区猪肝脏上清液中的硒主要以与高分子量蛋白结合的形式存在 .贵州汞污染地区猪肝脏上清液中汞主要与高分子量蛋白结合 ,而北京地区猪肝脏上清液中汞则分布较为均匀 .贵州万山地区猪肾脏上清液中 ,含硒峰在高分子量蛋白区和低分子量区都有分布 ;而北京地区猪肾脏上清液中 ,硒则主要集中分布于高分子量蛋白范围 .这两个地区猪肾脏上清液中都有分子量约为 11kD的金属硫蛋白 (MT)存在 ,北京地区猪肾脏上清液中汞主要以与金属硫蛋白结合的形式出现 ,而贵州万山地区猪肾脏上清液中的汞除与金属硫蛋白结合外 ,尚有相当大部分是以与高分子量蛋白结合的形式存在 .研究结果表明 ,由于这两个地区汞暴露水平的差异 ,不仅使这两地区猪肝、肾上清液中的汞与硒含量  相似文献   

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