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1.
Synchronisation of oestrus in Karagouniki ewes by administration of the standard dose of progesterone results in lower fertility than observed when these ewes ovulate naturally. This suggests that the optimum dose of progesterone may be breed dependent. The exogenous progesterone may perturb the concentrations of oestradiol-17beta and progesterone in blood plasma and the oviductal wall. This possibility was investigated using Karagouniki ewes allocated at random to three treatments (n=4 per treatment). Ewes were allowed to exhibit natural oestrus (N) or oestrus was synchronised by administration of 250 mg (LP) or 375 mg (HP) progesterone (subcutaneous implants) followed by PMSG at 8 mg/kg live weight i.m. 14 days later. Oestrus was observed using teaser rams. Blood samples were collected for plasma oestradiol-17beta and progesterone assay from the onset to the end of oestrus at 2 h intervals. The uterus of each ewe was recovered at the end of oestrus and samples of the oviductal wall were taken from both oviducts and prepared, separately, for progesterone and oestradiol-17beta assay. Statistical analysis was performed using univariate analysis of variance. Plasma oestradiol-17beta concentrations from the onset to the end of oestrus were highest for N ewes and lowest for HP ewes with the values for LP ewes occupying an intermediate position. The differences were significant (P<0.05) between HP and the other two treatments from 4 to 12 h after the onset of oestrus and then between all treatments until the end of oestrus. Plasma progesterone levels were similar and fairly constant from the onset to the end of oestrus for N and LP. The plasma progesterone levels for HP were significantly (P<0.05) higher than for the other two treatments throughout oestrus. In oviductal wall samples, the oestradiol-17beta concentration was significantly (P<0.05) higher for N ewes than for synchronised ewes and the levels were similar for LP and HP ewes. The concentration of oestradiol-17beta differed (P<0.05) between right and left oviducts for N ewes but not for ewes of either of the synchronised oestrus treatments. Progesterone concentrations in oviductal wall samples were highest (P<0.05) for HP ewes and the values for N and LP ewes were similar. The concentration of progesterone did not differ between right and left oviductal wall samples within treatments. It was concluded that the higher dose of exogenous progesterone perturbed the levels of oestradiol-17beta and progesterone in blood plasma and the oviductal wall, and this could explain the lower levels of fertility (relative to naturally occurring oestrus) observed when this protocol is used for Karagouniki ewes in practice.  相似文献   

2.
Sperm storage within the oviductal isthmus prior to ovulation typically involves binding to oviductal epithelial cells, which are thought to modulate sperm functions including internal calcium concentration, membrane fluidity, and motility. Around the time of ovulation the spermatozoa are gradually released so that they eventually encounter the oocytes within the oviductal ampulla. Previous studies have shown that the oviductal epithelial cells selectively sequester high quality spermatozoa, but the role of oviductal fluid as a selective modulator of sperm function has been investigated to a lesser extent. Here we address the hypothesis that oviductal fluid is also likely to modulate sperm function. Using samples of porcine oviductal fluid collected in the follicular phase of the estrus cycle, we show that short exposure (20 min to 50 μg/mL of oviductal fluid proteins) to either of two separate proteins fractions (> or < 100 kDa) promotes boar sperm viability and acrosomal integrity, decreases sperm plasma membrane fluidity (measured using merocyanine S540), and increases zona binding and polyspermy during in vitro fertilization. Exposure to the lower molecular fraction significantly inhibited, but did not abolish, the bicarbonate-induced stimulation of motility. The results show that subpopulations of spermatozoa respond differentially to oviductal fluid, and suggest that exposure to oviductal fluid in vivo could exert a further level of functional sperm selection.  相似文献   

3.
Virus-induced soluble antigens produced in mammalian cells after infection with vaccinia virus can be divided into two classes on the basis of molecular weight. Synthesis of the low molecular weight antigens begins early in the course of infection (1 to 2 hr), and is switched-off rather abruptly 4 to 5 hr after infection in a manner similar to that reported for the early enzymes characteristic of this same system. It was demonstrated, however, that these antigens do not include virus-induced thymidine kinase, a major virus-induced enzyme, nor is it likely that the low molecular weight antigens described here share identity with any of the virus-induced enzymes. A portion of the low molecular weight antigens appear to be incorporated into the structure of newly synthesized virus, probably as internal proteins. In contrast, synthesis of the high molecular weight antigen class is initiated later in the course of infection (4 to 5 hr), just prior to the appearance of newly synthesized virus. Antiserum directed specifically against virus structural proteins forms precipitin bands with all of the high molecular weight antigens recognizable by immunoelectrophoresis. This evidence, coupled with the observation that the high molecular weight antigen fraction elicits production of specific virus-neutralizing antibody, strongly suggests that this antigen class represents virus structural subunits produced in excess.  相似文献   

4.
Cohen, Gary H. (University of Pennsylvania, Philadelphia), and Wesley C. Wilcox. Soluble antigens of vaccinia-infected mammalian cells. I. Separation of virus-induced soluble antigens into two classes on the basis of physical characteristics. J. Bacteriol. 92:676-686. 1966-Infection of mammalian cells with members of the poxvirus group elicits production of a number of virus-induced, soluble antigens. Immunoelectrophoresis and immunodiffusion techniques employing soluble antigen preparations obtained from vaccinia virus-infected KB cells revealed at least seven well-defined immunoprecipitin bands. On the basis of fractionation and subsequent characterization of the soluble antigen mixture by gel filtration, calcium phosphate chromatography, isoelectric precipitation, disc electrophoresis, and ultracentrifugation studies, two distinct classes of virus-induced antigens differing markedly in molecular weight were recognized. A high molecular weight class (200,000 and greater) contained at least three virus-induced antigens; a low molecular weight class (50,000 to 100,000 range) contained at least four immunoprecipitins. Further separation of the antigens within the two groups was accomplished. The two classes were distinguished also by their ability to stimulate synthesis of virus-neutralizing antibody. Antisera prepared against the high molecular weight class proved effective in neutralizing vaccinia virus. In contrast, the low molecular weight antigens showed little, if any, ability to induce formation of neutralizing antibody.  相似文献   

5.
Soluble antigens of whole yeast-phase cells were extracted with a 0.1 M phosphate buffer containing 0.1 M sodium chloride and 0.02% iodoacetate. After being separated by differential filtration into fractions less than or greater than 50,000 daltons, these antigens were purified by molecular sieve and chromatographic separations on ionic exchange resins. Two high molecular weight fractions obtained from diethylaminoethyl-cellulose (DEAE) at pH 8.0 and 7.0 with tris (hydroxymethyl) aminomethane (Tris) buffer were M antigens; those obtained at pH 4.0 and 4.0 with salt were H antigens. The four fractions had protein to carbohydrate ratios of 7.3, 14.0, 8.4, and 6.5 respectively, and all had essentially the same amino acid composition with no methionine and tyrosine and little histidine, arginine, phenylalanine and lysine. They had high concentrations of glucose, less mannose and traces of galactose. The low molecular weight fractions had the new complex Y antigen, M antigen, and H antigen with protein to carbohydrate ratios of 1.4, 1.4 and 0.3 respectively. The amino acid and sugar composition of Y antigen strongly resembled the composition of the low molecular weight H and M antigens. Unlike the high molecular weight antigens, these low molecular weight antigens had methionine in relatively high concentrations; they had the same sugars as their respective high molecular weight counterparts. The yeast phase antigens differed from their respective mycelial counterparts in the following ways: glucose was the major sugar in the yeast phase with less amounts of mannose and traces of galactose, whereas in the mycelial antigens, mannose was the major sugar, with lesser amounts of galactose, glucose, and hexosamine. The H and M antigens of the yeast phase had high concentrations of glycine and alanine, whereas in the mycelial phase, these antigens had high concentrations of threonine and proline; the H and M antigens of the yeast phase had 5 to 16 times the protein to carbohydrate ratio observed for the same antigens of histoplasmin.  相似文献   

6.
Antisera raised against the soluble antigens of the endometrium of early pregnancy detected two antigenic proteins of alpha 1 and alpha 2 mobility in extracts of this tissue and were termed antigens A and B. Neither antigen was detected in pregnancy sera or extracts of proliferative endometrium, but antigen B was detected in extracts of secretory endometrium and both were present in amniotic fluid and medium from in-vitro incubations of pregnancy endometrium. Fractionation of radiolabelled medium on ion-exchange chromatography demonstrated that antigens A and B co-eluted with the proteins from which EP14 and EP15 were derived and which were the major secretory polypeptides of pregnancy endometrium in vitro. Further biochemical purification revealed that EP14 (Mr 32 000) was derived from a protein of native molecular weight 36 000 which existed in two forms, whereas EP15 (Mr 28 000) was derived from a dimeric glycoprotein of native molecular weight 56 000. Immunochemical studies demonstrated that antigens A and B are identical to these two secretory proteins and have been termed pregnancy-associated endometrial alpha 1- and alpha 2-globulins (alpha 1- and alpha 2-PEG).  相似文献   

7.
1. Methods for the extraction and purification of the immobilization antigens of Paramecium aurelia have been developed. 2. The immobilization antigen was shown to be a protein of molecular weight 250000. The amino acid content of two allelic antigens and one controlled by a separate genetic locus was determined and many differences were observed. 3. The properties of antigen denatured by reduction and alkylation were examined. The molecular weight fell to 80000 or perhaps less. 4. Peptide maps of allelic types were more similar than those of types controlled by different genetic loci. 5. It is suggested that the antigen consists of two identical half-molecules held together by disulphide bonds. These half-molecules may contain further sub-units.  相似文献   

8.
High dietary protein leads to elevated systemic concentrations of ammonia and urea, and these, in turn, have been associated with reduced fertility in cattle. The effect of elevating systemic concentrations of ammonia and urea on the concentrations of electrolytes and nonelectrolytes in bovine oviductal fluid were studied using estrus-synchronized, nulliparous heifers (n = 25). Heifers were randomly assigned to 1 of 3 treatments consisting of jugular vein infusion with either ammonium chloride (n = 8), urea (n = 8), or saline (n = 9). Oviducts were catheterized, and fluid was recovered over a 3-h period on either Day 2 or 8 of the estrous cycle. No difference (P > 0.05) was found in the concentrations of any electrolyte or nonelectrolyte between oviducts ipsi- or contralateral to the corpus luteum. Plasma and oviductal concentrations of urea were increased by infusion with urea (P < 0.001) and ammonium chloride (P < 0.05) but not by saline (P > 0.05). Plasma and oviductal concentrations of ammonia were elevated by infusion with ammonium chloride (P < 0.001) but not by infusion with urea or saline (P > 0.05). No effect (P > 0.05) of treatment was found on oviductal or plasma concentrations of glucose, lactate, magnesium, potassium, or sodium or on plasma concentrations of insulin or progesterone. The concentration of calcium in oviductal fluid was reduced by urea infusion and was negatively associated with systemic and oviductal concentrations of urea. Oviductal concentrations of sodium were higher on Day 8 than on Day 2 (P < 0.05). No effect of sample day was found on any of the other electrolytes or nonelectrolytes measured (P > 0.05). Elevated systemic concentrations of ammonia and urea are unlikely to reduce embryo survival through disruptions in the oviductal environment.  相似文献   

9.
The final stages of sperm maturation, fertilization and early embryonic development take place in the microenvironment of the oviduct and are essential for successful reproduction in mammals. Although catecholamines have been shown to have beneficial effects on mammalian gametes in vitro, identification of catecholamines in native bovine oviductal fluid has not been studied. The objective of this research was to identify catecholamines in bovine oviductal fluid and to determine whether concentrations of catecholamines change with stage of the estrous cycle. Oviductal fluid was collected via indwelling oviductal cannulae and assayed for the presence of catecholamines by high performance liquid chromatography. Norepinephrine was the only catecholamine detected, in concentrations ranging from 0.828 ng/ml - 1117 ng/ml. The presence of norepinephrine in oviductal fluid corresponded to a period of time just prior to, during, and after ovulation, when serum progesterone levels were low. This was a consistent finding in ODF collected from normally cycling cows. Potential functions of norepinephrine in oviductal fluid include regulation of fluid formation, induction of capacitation and the acrosome reaction in spermatozoa, and cleavage of the early embryo.  相似文献   

10.
Hybridoma technology was applied in an effort to create highly specific probes for nonhistone proteins associated with human colon cancer nuclear matrix. Three stable monoclonal antibodies producing cloned cells No. 39, 54 and 58 are described here. All these antibodies showed high reactivity with human colon tumor nuclear matrix. Both antibodies No. 39 and 58 showed an extensive cross reactivity at high concentration of normal colon nuclear matrix. The antigens were determined to be a heterogeneous group of proteins with a major antigen of molecular weight of 140,000 for antibody No. 54 subclone 54-c-5-6 and two major antigens of molecular weight for 105,000 and 116,000 for antibody No. 39 subclone 39-d-11-12. Immunohistochemical localization of the antigens by the horseradish peroxidase bridge method demonstrated their presence in the nuclei.  相似文献   

11.
In cattle, increasing early embryonic losses are associated with inadequate progesterone concentrations within the first three weeks of pregnancy. The aim of this study was to investigate the complex relationship between early maternal progesterone concentration and embryo development early within the first week of pregnancy, specifically, on day 5 post-oestrus in dairy cows. Twenty Holstein-Friesian cows at the end of lactation were inseminated at oestrus (day 0) and on day 5 post-oestrus cows were slaughtered and the reproductive tract flushed to determine the presence and stage of embryo development. Three cows that had failed to synchronise correctly were excluded from analysis while in the remaining 17 cows 11 (65%) were pregnant with embryos at the morula (n = 3), 9-16 (n = 3) and 8-cell (n = 5) stages of development. No differences in day 5 plasma progesterone concentrations or corpus luteum (CL) size or progesterone content were observed between pregnant (n = 11) and non-pregnant (n = 6) cows. In cows with embryos beyond the 8-cell stage of development (n = 6) plasma progesterone concentration (P < 0.001) and CL weight (P < 0.01) were higher and plasma insulin concentrations lower (P < 0.001) than in cows with 8-cell embryos (n = 5). In addition there was a negative relationship between plasma progesterone and plasma insulin in pregnant cows (R(2) = 0.65; P < 0.005). In cows with an embryo present in the oviduct, oviductal glucose concentrations were lower (P < 0.05) than in cows with no embryo present. These results confirm progesterone is not only directly associated with embryo development, but that it may indirectly modulate embryo development via changes in the oviductal environment. In summary, the association between maternal progesterone concentration and embryo development exists as early as day 5 of pregnancy in dairy cows.  相似文献   

12.
《Reproductive biology》2022,22(1):100616
The oviduct is a dynamic organ that has not been assigned specific functions during advanced pregnancy. However, since changes in the oviductal epithelium during the estrous cycle are attributed mainly to variations in estradiol (E2) levels, and E2 levels increase along pregnancy, we hypothesized that advanced pregnant cows should present changes in the oviductal epithelium. In advanced pregnant cows, the oviducts showed higher leaf-like folds and lower mucosa width and epithelium height than those of cycling animals. Also, PAS-positive apical protrusions and TUNEL-positive extruded cytoplasmic material were observed in advanced pregnant cows. Oviductal fluid from advanced pregnant cows showed lower protein concentration than that from cycling cows. Transglutaminase 2 (TG2) was detected exclusively in oviductal fluid of pregnant cows but not in cells from any stage, whereas its mRNA was detected in different amounts in cells from all stages. This protein was identified by LC/MS-MS and its identity was corroborated by Western blot. The observations in histology of the epithelium and the presence of TG2 in oviductal fluid correlate with high levels of E2 in serum. In conclusion, important histological changes in the oviductal epithelium and secretion of TG2 to the oviductal fluid appear to be triggered by the high E2 levels exclusive of advanced pregnancy.  相似文献   

13.
Human follicular fluid (hFF), which has been treated with either unspecific proteases or dextran-coated charcoal (DCC) to remove proteins and/or steroids, cannot successfully induce the acrosome reaction (AR). After the removal of steroids, AR-inducing activity can be restored to hFF by supplementation with exogenous progesterone, but only in the presence of intact protein. Gel filtration experiments with 3H-progesterone-labelled hFF showed elution of the radioactive signal in the high molecular weight range, corresponding to bound progesterone. AR-inducing activity was seen in exactly the same fraction. Based on these results, the acrosome reaction-inducing substance (ARIS) appears to be a complex of progesterone and a progesterone-binding protein, which was shown to be identical with the plasma protein corticosteroid-binding globulin (CBG) by immunological techniques. AR induction was only observed in the presence of both CBG and progesterone, suggesting a combined effect of the two components. © 1995 wiley-Liss, Inc.  相似文献   

14.
The use of antigens from excretions and secretions (ESA) of Schistosoma mansoni in two immunodiagnostic tests, the enzyme-linked immunosorbent assay (ELISA), and the defined antigen substrate spheres (DASS) system, has been extensively investigated. In comparison with total adult worm antigens (AWA), the sensitivity of the DASS tests remained the same, while that of the ELISA increased slightly when ESA was used. For further analysis, the ESA preparation was fractionated according to molecular weight, by gel filtration. The humoral immune response of immunized rabbits, infected mice, and humans to each of these molecular-weight fractions was determined by incubating an equal, nonsaturating amount of each ESA fraction in a double-antibody sandwich system, using Sepharose beads as a carrier. The humoral immune response of rabbits immunized with ESA was primarily directed against antigens with molecular weight between 50,000 and 70,000. In contrast, immunoglobulins from sera of infected mice or humans, reacted well with antigens from a large molecular-weight range. Screening of a large number of sera for the presence of specific antibodies is most conveniently executed with tests in which antigens, instead of antibodies, are bound to a matrix. However, binding of antigens to Sepharose beads or polystyrene microtiter plates was shown to decrease considerably with decreasing molecular weight of the antigen. Therefore, of all ESA fractions, those containing the high-molecular-weight antigens (MW > 200,000) gave the most sensitive DASS and ELISA tests. These high-molecular-weight excretory and secretory antigens, in contrast to a total-worm homogenate, and excretory and secretory antigens with a molecular weight lower than 200,000, possessed a high specificity for S. mansoni. The specificity of the high-molecular-weight preparation was shown to be mainly due to the presence of the circulating anodic polysaccharide antigen, since removal of this antigen by immunoadsorption led to a considerable decrease in specificity.  相似文献   

15.
Based on the expression of hormone receptors, oviductal cells receive a series of signals to control the conduit and transport of gametes. Most cells in the inner oviductal mucosa have motile cilia, and the mucociliary system of oviducts represents a prominent object of study for rapid feedback after application of steroid hormones. Using a high-speed reflectometry method, we investigated effects on the ciliary beat frequency (CBF) of bovine oviductal explants after progesterone treatment. To classify changes of CBF as either classic or non-classic reactions, we pretreated primary tissue cultures with mifepristone, an antagonist to the classic progesterone receptor in a second experimental series. In contrast to classical genomic reactions, non-classic or non-genomic reactions are characterized by fast effects, insensitive to the classic receptor antagonist. We observed inhibitory effects on the ciliary beat frequency as soon as 15 minutes after application of progesterone (20 microM), reaching a plateau of about 11 % after 90 minutes. Pretreatment with mifepristone (20 microM) for two hours did not induce significant differences in short-term reactions. However, the inhibitory influence of progesterone after 24 hours could be effectively prevented. Our data confirmed the short-term reaction of CBF as non-genomic or non-classic.  相似文献   

16.
Previously, we identified a 215 kd glycoprotein, GP215, which is associated with postovulatory oocytes and embryos, but not with preovulatory oocytes (Kapur and Johnson, '85). In this paper a polyclonal antibody that specifically recognizes GP215 has been used to study the distribution of the molecule in association with ova and preimplantation embryos and in the female reproductive tract. GP215 is present in epithelial cells lining the cranial portions of the oviduct and in oviductal fluid, ovarian bursal fluid, and medium conditioned by oviductal tissue in vitro. Immunofluorescence assays of the ovum and early embryo show that GP215 is sequestered in the perivitelline space. Since preovulatory oocytes exposed to bursal fluid in vitro acquire GP215, we hypothesize that GP215 is synthesized and secreted by the oviductal epithelium and secondarily associates with the ovulated oocyte. Sequestration of GP215 within the perivitelline space is relatively specific since mouse serum albumin, a major constituent of oviductal fluid, and other high molecular weight proteins are not similarly retained. These observations indicate that the composition of the perivitelline space may be significantly different from the greater environment external to the zona pellucida such that fertilization and early development of mammalian ova potentially take place in a distinct perivitelline microenvironment.  相似文献   

17.
J H Kuh  K S Kim  S H Kim  K W Cho  K H Seul  G Y Koh 《Life sciences》1990,46(26):1977-1983
The epicardial release of immunoreactive atrial natriuretic peptides (ir-ANPs) in inside-out perfused rabbit atria has been reported. In order to determine the presence of ir-ANPs in pericardial fluid and to evaluate their biochemical characteristics, we measured the concentration of ir-ANPs in pericardial fluid obtained from the patients with congenital heart diseases during open heart surgery. Serial dilution curves made with the extrats of pericardial fluid using Sep-Pak C18 cartridges were parallel with standard curve. The concentration of ir-ANPs in pericardial fluid was significantly lower than the corresponding plasma concentration. On gel permeation and reverse-phase high performance liquid chromatography, the ir-ANPs in pericardial fluid, plasma and atrial appendage showed both high and low molecular weights. The major peak of ir-ANPs in plasma was observed at the corresponding fraction to the alpha-human ANP and considerable amount of high molecular weight form of ir-ANPs was observed in pericardial fluid. However, the major peak of ir-ANPs in atrial appendage was observed at the corresponding fraction to the rat pro-ANP. The data suggest that ir-ANPs exist both high and low molecular weight forms in pericardial fluid.  相似文献   

18.
本文旨在建立基于高效体积排阻色谱(high-performance size-exclusion chromatography,HPSEC)偶联多角度激光散射仪(multi-angle laser light scattering,MALLS)的猪圆环病毒2型(porcine circovirus type 2,PCV2)疫苗抗原检测方法。以纯化的PCV2灭活病毒及病毒样颗粒(virus-like particles,VLP)为参照,对4家生产企业的2种PCV2灭活病毒疫苗(a、b)及VLP疫苗(c、d)破乳后进行HPSEC-MALLS检测及分子量分析;结合PCV2抗原检测卡、Western blotting和透射电子显微镜(transmission electron microscope,TEM),鉴定了特征色谱峰;考察了方法的重复性和检测线性。结果表明,两家企业生产的PCV2灭活病毒疫苗破乳液水相经HPSEC分离,在保留时间约13.3 min处出现抗原特征峰;MALLS计算该色谱峰分子量分别为2.61×106(±4.34%) Da和2.40×106(±2.51%) Da。两种VLP疫苗也在13.3 min处出现抗原特征峰,分子量分别为2.09×106(±2.94%) Da和2.88×106(±11.85%) Da,接近PCV2的理论分子量;同时在保留时间约11.4 min处也出现色谱峰,经检测分子量为4.37×106(±0.42%) Da,TEM表征显示为VLP二聚体。取疫苗d和PCV2 VLP纯品进行重复检测,抗原色谱峰面积的RSD(n=3)均小于1.5%,重复性好;将PCV2 VLP纯品梯度稀释检测,VLP及其多聚体的色谱峰面积与浓度均呈良好的线性关系,R2分别为0.999及0.997,能够满足定量及多聚体含量分析。该方法有望成为一种准确、高效的PCV2疫苗的体外评价方法,用于质量评价与提升。  相似文献   

19.
Xenoantisera were raised to total chromatin from the leukemia cell line K562, or materials released through limited deoxyribonuclease I digestion of nuclei or during the control incubation of nuclei without enzyme. The peroxidase-antiperoxidase method of antibody-antigen detection was employed to visualize individual antigens resolved on one-dimensional polyacrylamide gels following transfer to sheets of nitrocellulose (immunotransfers). Each antiserum contained multiple antigen specificities as evidenced by the diverse patterns of reactive bands displayed on the immunotransfers. The most striking difference in antigens recognized between the antisera was observed in the molecular weight region below 50,000, where two highly reactive bands were seen mainly with antiserum to nuclear materials released by deoxyribonuclease I digestion. The antigens detected with all of the antisera were present in chromatins prepared from proliferating cells, while the levels of antigens present in chromatin from non-proliferating peripheral blood lymphocytes were greatly reduced or not detected. Antigens in chromatin from proliferating cells that migrated with apparent molecular weights of 37,000 and 100,000 were not lost once the activities to antigens in lymphocyte chromatin were absorbed out. These two activities were absorbed from antisera with the same amount of chromatins from proliferating cells. Two antigens migrating at molecular weight 52,000 and 76,000 appeared more active in the chromatin from unstimulated lymphocytes than in chromatin from proliferating cells.  相似文献   

20.
To identify sources of high potency antigens for use in serodiagnosis, aqueous-soluble egg antigens from Schistosoma japonicum were extracted with Dulbecco's phosphate-buffered saline. Residual particulates were solubilized with Tris-buffered 8 M urea, yielding a urea-soluble egg antigen fraction. The urea-soluble fraction was further fractionated with Bio Gel A50m and QAE-Sephadex. All fractions were quantitatively assayed for their specific antigenic activities against serum specimens from infected rabbits by the single-tube enzyme-linked immunosorbent assay (k-ELISA). In antigen rate-limiting conditions, the urea-soluble particulate fractions were more antigenically active than the aqueous-soluble fraction. In antigen-excess and antibody-limiting assay conditions, the ideal conditions for serologic assays, the urea-derived antigens also showed superior activities against sera from infected humans. Analysis by SDS-polyacrylamide gel electrophoresis (SDS-PAGE) on gradient gels revealed numerous low molecular weight protein bands in the aqueous-soluble fraction, whereas the urea-soluble fractions appeared to be much simpler with the majority of their proteins concentrated in one or two high molecular weight bands (greater than or equal to 200 kdaltons). Electro-transfer blots of the SDS-PAGE onto nitrocellulose papers and subsequent visualization of antigens by enzyme-linked immunoabsorbence confirmed these findings. The above data suggest that the urea-soluble fraction of S. japonicum eggs is antigenically active and has potential use in the development of a diagnostic reagent.  相似文献   

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