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1.
The IgE receptor of human basophils was purified by using simple and repetitive affinity chromatography on human IgE-Sepharose. Basophils were partially purified from peripheral blood of patients with chronic myelogenous or basophilic leukemia. Cells were labeled with 125I by using the lactoperoxidase method and were solubilized with nonionic detergent. Elution of IgE-Sepharose with 0.5 N acetic acid, 1% NP-40 allowed recovery of active IgE receptor. Analysis of human IgE receptor by SDS polyacrylamide gel electrophoresis with 10% gels demonstrated one major radioactive peak with an apparent m.w. of 58,000 to 68,000, somewhat larger than rat IgE receptor. The purified human IgE receptor was active since approximately 10 to 42% of labeled receptor could specifically rebind to insolubilized human IgE. Rebinding was blocked by nanomolar concentrations of soluble human IgE or rat IgE but not by human or rat IgG, heat-inactivated human IgE, or heat-aggregated human IgG; thus it appears that rat IgE receptor. The relative abilities of active rat IgE and active human IgE to inhibit human IgE receptor rebinding could not be precisely determined because of the limitations in assessing the proportion of human IgE that retains receptor-binding activity.  相似文献   

2.
The hemizona assay is a diagnostic test used to evaluate the binding potential of spermatozoa to zonae pellucida and has been used to predict fertilization potential in the human. In this study, frozen-thawed gorilla spermatozoa were coincubated with human hemizonae to evaluate tight binding and to assess the use of human zonae in evaluating sperm fertility. Matching hemizonae were incubated with human sperm to serve as a control. For evaluation of binding studies in a homologous system, matching halves of gorilla hemizonae were coincubated with both gorilla and human sperm. Whole, intact zonae of both human and gorilla oocytes were also coincubated with heterologous sperm to determine if penetration into the perivitelline space could occur. This study found that gorilla sperm bound well to both gorilla and human hemizonae, with a mean of 112.5 and 81.0 tightly bound sperm, respectively. Human sperm also bound to gorilla (mean 229.5) and human (mean 236.5) hemizonae. Following incubation with intact gorilla zonae, motile human sperm were found within the perivitelline space. However, gorilla sperm were not visible within the perivitelline space of nonviable human oocytes. These findings demonstrate that the zonae of nonviable human oocytes can be used to assess sperm binding of gorilla sperm. Studies continue for optimizing assay condition and correlation of findings with the fertility potential of gorilla sperm.  相似文献   

3.
Human–dog interaction relies to a large extent on nonverbal communication, and it is therefore plausible that human sensitivity to nonverbal signals affects interactions between human and dog. Experience with dogs is also likely to influence human–dog interactions, and it has been suggested that it influences human social skills. The present study investigated possible links between human nonverbal sensitivity, experience with dogs, and the quality of human–dog interactions. Two studies are reported. In study 1, 97 veterinary students took a psychometric test assessing human nonverbal sensitivity and answered a questionnaire on their experience with dogs. The data obtained were then used to investigate the relationship between experience with dogs and sensitivity to human nonverbal communication. The results did not indicate that experience with dogs improves human nonverbal sensitivity. In study 2, 16 students with high, and 15 students with low, levels of human nonverbal sensitivity were selected. Each of the 31 students interacted once with an unknown dog in a greeting situation, and these human–dog interactions were videoed. We found that a combined score of dog behaviors relating to insecurity was associated with the students' level of nonverbal sensitivity and experience with dogs: the dog showed more of the insecure behavior when interacting with students with a low level of nonverbal sensitivity and no experience with dogs than it did when interacting with students with a high level of nonverbal sensitivity (irrespective of experience with dogs).  相似文献   

4.
裸鼠肿瘤动物模型VEGF受体表达及其意义   总被引:4,自引:1,他引:4  
目的 通过免疫组织化学染色了解flt 1与flk 1 KDR(VEGF的两个高亲和受体 )在人肿瘤细胞皮下接种肿瘤动物模型的血管内皮细胞与肿瘤细胞中的表达。方法 取荷瘤裸鼠皮下接种瘤块 ,漂洗、固定、石蜡连续切片 ,进行两种受体相应免疫组化检测。结果 在 13种荷瘤裸鼠血管内皮细胞及肿瘤细胞中flt 1的阳性率大部分为强阳性或中阳性 ,而只有在荷人胃腺癌MKN 4 5裸鼠的肿瘤细胞中flt 1的阳性率为弱阳性 ,在荷人卵巢癌SKOv3裸鼠的肿瘤细胞中flt 1的表达为阴性。相比较而言 ,在 13种荷瘤裸鼠血管内皮细胞及肿瘤细胞中KDR的阳性率大部分为中阳性或弱阳性 ,并且在荷人肝癌SMMC 772 1裸鼠 ,荷人胃腺癌SPC A1裸鼠 ,荷人高转移肝癌移植瘤裸鼠 ,荷人卵巢癌SKOv3裸鼠的肿瘤细胞中 ,荷人宫颈癌移植瘤裸鼠和荷人胃腺癌MKN 4 5裸鼠的肿瘤细胞中 ,KDR表达为阴性。结论 VEGF受体共同表达于肿瘤血管内皮细胞与肿瘤细胞 ,提示了VEGF与VEGF受体结合作用在肿瘤演化中的重要性 ,为靶向于VEGF受体的基因治疗策略选择裸鼠动物模型提供了参考依据  相似文献   

5.
Human liver contains a small molecular weight protein (SMWP) previously shown to be biochemically homologous with a chicken liver protein in terms of its amino acid residues. This human protein, which reacts immunologically as a human serum protein, has been tested for its reactions against a battery of antisera that react specifically with many of the human serum proteins. Material prepared from four human livers gave strong reactions in double gel immunodiffusion with an antiserum against human albumin. One of the liver preparations reacted weakly with antiserum against human ferritin; this ferritin is assumed to be a contaminant. Because of the biochemical homology of human liver SMWP with chicken liver SMWP the latter would be expected to react immunologically as serum albumin.  相似文献   

6.
牛SRY同源基因的PCR扩增和克隆   总被引:1,自引:0,他引:1  
本文采用人SRY基因的一对引物,通过PCR扩增获得了雄性牛(Bos taurus)SRY同源基因片段。进一步证实牛存在与人SRY基因同源的相应基因。将PCR产物与载体pUC—Eco—T连接后,用以转化JM109菌,经过与人SRY基因探针菌落杂交,筛选获得了牛SRY同源基因克隆pBosY O.6后者的插入片段为相应于人SRY基因保守区在内的一段约609bp DNA。此外还比较分析了人和牛SRY同源基因片段限制酶图谱。  相似文献   

7.
Species restrictions in immune cell interactions have been demonstrated both in Ag-specific responses of T lymphocytes and the phenomenon of natural attachment. To determine the possible contribution of adhesion receptors to these restrictions, we have studied binding between the murine and human homologues of LFA-1 (CD11a/CD18) and ICAM employing purified human LFA-1 and ICAM-1 (CD54) bound to solid substrates. Murine cell lines bind to purified human LFA-1 through ICAM-1 and at least one other counter-receptor. This provides evidence for multiple counter-receptors for LFA-1 in the mouse as well as in the human. In contrast to binding of murine ICAM-1 to human LFA-1, murine LFA-1 does not bind to human ICAM-1. The species specificity maps to the LFA-1 alpha subunit, because mouse x human hybrid cells expressing the human alpha subunit associated with a mouse beta subunit bind to human ICAM-1, whereas those with a human beta subunit associated with a murine alpha subunit do not. Increased adhesiveness for ICAM-1 stimulated by phorbol esters could be demonstrated for hybrid LFA-1 molecules with human alpha and murine beta subunits.  相似文献   

8.
The polymerase chain reaction is an in vitro method for primer directed enzymatic amplification of specific target DNA sequences. The technique was used to detect human papillomavirus types 11 and 16 simultaneously in cellular DNA recovered from cervical smears in 38 women referred for colposcopy to evaluate cytological abnormality and 10 women with no history of cytological abnormality. The polymerase chain reaction was shown to be both specific and sensitive in detecting human papillomavirus DNA such that a single human papillomavirus molecule was detected in 10(5) cells. Of the 38 women with cytological abnormality, all were positive for human papillomavirus on testing with the polymerase chain reaction; 36 were infected with human papillomavirus type 16 and 22 dually infected with human papillomavirus types 11 and 16. Seven of the 10 women with no cytological abnormality were also infected with human papillomavirus type 11 or 16. The use of the polymerase chain reaction will facilitate epidemiological investigation of the aetiological role of human papillomavirus in cervical neoplasia. This preliminary analysis suggests that the prevalence of human papillomavirus infection is greater than previously reported.  相似文献   

9.
We obtained 10/192 and 3/384 antibody-secreting hybrids after immunization of Balb/c mice with either human growth hormone or affinity-purified rabbit anti-(human growth hormone) respectively. Radiolabelled rabbit anti-(human growth hormone) antibodies, but not human growth hormone, were specifically bound by supernatants from the 13 hybrids. The binding was completely inhibited by human-growth-hormone serum binding protein. However, anti-(human growth hormone antibodies) were detected in the sera of all the mice immunized with human growth hormone. In an independent fusion, which was carried out after immunization with fewer doses of human growth hormone, anti-(human growth hormone) antibodies were also obtained. Five hybrids, where the starting antigen was human growth hormone, were selected for ascites production, and the corresponding monoclonal antibodies were partially purified and characterized with respect to their immunoglobulin isotype and their interaction with human-growth-hormone receptors. These antibodies were found to enhance the binding of radioiodinated human growth hormone to human-growth-hormone serum binding protein from human and rabbit plasma by 40%. Scatchard analysis of the effect of one of the monoclonal antibodies showed that this enhancement was due to an increased number of binding sites. All of the partially purified antibodies but one (F12) inhibited the binding of human growth hormone to rat but not rabbit, liver microsomes to various extents, as well as to H-4-II-E rat hepatoma cells. Monoclonal antibody F12 enhanced the binding of radiolabelled human growth hormone to rat liver microsomes and H-4-II-E hepatoma cells. This enhancement was found to be due to an increase in the number of binding sites.  相似文献   

10.
The mechanism of interferon action in human fibroblasts has been studied by use of both antisera to human fibroblast interferon and the antisera to the surface of human fibroblast cell. The anti-interferon serum completely neutralized the antiviral effect of human fibroblast interferon. Interferon antiserum prevented the intracellular antiviral state from developing when added to the medium of the cells in which interferon synthesis had already been induced by poly (I · C). This suggests that development of the antiviral state involves interferon interaction with the external part of the producing cell. Treatment with the serum directed against the surface of human fibroblast cells failed to inhibit the antiviral activity of human interferon in these cells. In addition, the effect of gangliosides on the antiviral activity of human interferon was studied and it was found that human interferon binds to gangliosides and that this interaction leads to inactivation of the antiviral effect of interferon. Pretreatment of human fibroblasts with gangliosides had no effect on the sensitivity of these cells to exogenous interferon.  相似文献   

11.
A Deisseroth  D Hendrick 《Cell》1978,15(1):55-63
We have used the genetic marker, adenine phosphoribosyl transferase (APRT), an enzyme known to be on human chromosome 16, to establish a method for the transfer of human α-globin genes into mouse erythroleukemia cells. Mouse erythroleukemia cells devoid of detectable levels of APRT were fused with fractions of human marrow enriched in human erythroid cells. The hybrid cells arising from this fusion were isolated in medium supplemented with aminopterin and thymidine, and used adenine as the sole purine source. This population of hybrid cells was dominated by cells (80%) in which human chromosome 16 was present. Human chromosomes 4, 5 and 6 were also found in these cells. The hybrid cells were then placed in medium supplemented with diaminopurine (DAP), which is lethal for cells containing APRT. Greater than 95% of the DAP-selected hybrid cells lacked human chromosome 16. Cytoplasmic RNA was extracted from the two hybrid cell populations and assayed by molecular hybridization for sequences coding for human α-globin. Carboxymethyl cellulose chromatography was used to study the level of synthesis of human a-globin in the hybrids. The original hybrid cell, which contained a high frequency of human chromosome 16, also contained high levels of human a-globin mRNA and human α-globin chains. Hybrid cells counter-selected in DAP and thus lacking human chromosome 16 were devoid of detectable levels of human APRT, human α-globin mRNA and human α-globin chains. This work shows that transfer of human chromosome 16 into the MEL cell is possible using a chromosomedependent, APRT-mediated method of gene transfer. Using this system in which expression of the human α-globin gene occurs, we were also able to confirm our earlier assignment of the human α-globin gene to human chromosome 16. This system may be of further use in identifying genetic elements governing expression of the human α-globin gene which can be carried with human chromosome 16 as it is donated to the mouse erythroleukemia cell by donor cells of different epigenotypes.  相似文献   

12.
Hemopoietic stem cell factor (SCF), which is the ligand for the proto-oncogene c-kit receptor (allelic with W locus) and the product of Sl locus of the mouse, has recently been cloned. The human homologue has also been cloned, and recombinant protein (human rSCF) expressed and purified to homogeneity. To determine the effect of human rSCF in the presence or absence of human rIL-3 on human bone marrow-derived mast cells and basophils, human CD34+ pluripotent progenitor cells, highly enriched (greater than 99%) from bone marrow mononuclear cells, were cultured over agarose surfaces (interphase cultures) in the presence of human rIL-3, human rIL-3 and increasing concentrations of human rSCF, or human rSCF alone. Over 3 to 4 wk, human rSCF acted synergistically with human rIL-3 at all concentrations, producing a three- to fivefold increase in total, mast cell, and basophil numbers over human rIL-3 alone when used at 100 ng/ml. The percentage of cell types in the human rIL-3 and human rIL-3 plus human rSCF cultures, however, remained the same, with basophils constituting 18 to 35% of the final cultured cells, and mast cells 3% or less of the final cell number. In the presence of human rSCF alone, the combined total percentage of mast cells and basophils was 0 to 1.0%, the majority of cells being macrophages. Mast cells cultured in human rIL-3 plus human rSCF, but not human rIL-3 alone, were berberine sulfate positive, suggesting the presence of heparin proteoglycans within granules. Electron microscopic examination of cultures supplemented with human rIL-3 and rSCF, but not human rIL-3 alone, revealed that after 3 wk in culture, mast cell granules contained tryptase and exhibited scroll, reticular, and homogeneous patterns as seen previously in CD34+/3T3 fibroblast cocultures. Thus, CD34+ cells cultured in the presence of both human rIL-3 and rSCF give rise to cultures containing increased numbers of basophils and mast cells, with the mast cells by ultrastructural studies showing evidence of maturation although the percentages of basophils and mast cells arising in these cultures remained unchanged.  相似文献   

13.
The immunological relatedness of human and porcine growth hormones is examined by means of labelled human growth hormone and guinea pig antiserum. 1) Labelled human growth hormone is found in the precipitate after reaction with antiserum against porcine growth hormone. Parallel dilution curves are obtained with antisera against human and porcine growth hormones. 2) After addition of antiserum against porcine growth hormone, all the radioactivity is eluted from Sephadex G-100 with the void volume. 3) The addition of an excess of porcine hormone displaces labelled human growth hormone from antibodies against human growth hormone to the same extent as an excess of non-labelled human growth hormone does. 4) The standard radioimmunoprecipitation curves for porcine and human growth hormones obtained in the assay system for the human hormone are parallel in slope, provided that the human hormone and our preparation of the porcine hormone are introduced at a proportion of 1 to 560. 5) In a double diffusion test in agarose gel layers, with human and porcine growth hormones diffusing against guinea pig anti-porcine serum, cross reaction is observed. The conclusion is drawn that with guinea pig antisera, human and porcine growth hormones behave immunologically in a similar fashion. Labelled human growth hormone seems to have only such immunodeterminants as are also found in porcine growth hormone.  相似文献   

14.
Here we show that transplantation of autologous human hematopoietic fetal liver CD34+ cells into NOD/SCID mice previously implanted with human fetal thymic and liver tissues results in long-term, systemic human T-cell homeostasis. In addition, these mice show systemic repopulation with human B cells, monocytes and macrophages, and dendritic cells (DCs). T cells in these mice generate human major histocompatibility complex class I- and class II-restricted adaptive immune responses to Epstein-Barr virus (EBV) infection and are activated by human DCs to mount a potent T-cell immune response to superantigens. Administration of the superantigen toxic shock syndrome toxin 1 (TSST-1) results in the specific systemic expansion of human Vbeta2+ T cells, release of human proinflammatory cytokines and localized, specific activation and maturation of human CD11c+ dendritic cells. This represents the first demonstration of long-term systemic human T-cell reconstitution in vivo allowing for the manifestation of the differential response by human DCs to TSST-1.  相似文献   

15.
大熊猫SRY基因的PCR扩增和克隆   总被引:9,自引:0,他引:9  
张思仲  周荣家 《遗传学报》1994,21(4):281-286
本文采用人SRY基因的一对引物,通过PCR扩增获得了雄性大熊猫SRY基因片段。表明大熊猫存在与人SRY基因同源的相应基因,将PCR产物与载体pUC-Eco-T连接后,用以转化JM109菌,经过与人SRY基因探针菌落杂交筛选获得了大熊猫SRY苈在克隆,命名为pAMY0.6,其插入片段为相应于人SRY基因保守区在内的一段约609bpDNA。此外,还制作和比较分析了人和大熊猫基因片段的限制酶图谱。  相似文献   

16.
F W Leebeek  D M Fowlkes 《FEBS letters》1992,306(2-3):262-264
We have constructed several hybrid human interleukin-6 (IL-6) variants in which the carboxyl-terminus, which includes a receptor binding site of IL-6 has been replaced with the C-terminus of various proteins homologous to human IL-6. IL-6 hybrids with the C-terminus of human growth hormone and human granulocyte-colony stimulating factor maintain part of the biological activity of human IL-6. Replacing the C-terminus of human IL-6 with the C-terminus of mouse and rat IL-6 resulted in a normal or increased activity on a mouse cell line; however, this gave a low (to 200-fold less) activity on a human cell line compared to wild-type human IL-6. We therefore conclude that the C-terminus of IL-6 plays an important role in the species specificity of IL-6.  相似文献   

17.
The structural gene for the human lysosomal enzyme aspartylglucosaminidase (AGA) has been assigned to chromosome 4 using somatic cell hybridization techniques. The human monomeric enzyme was detected in Chinese hamster-human cell hybrids by a thermal denaturation assay that selectively inactivated the Chinese hamster isozyme, while the thermostable human enzyme retained activity. Twenty informative hybrid clones, derived from seven independent fusions, were analyzed for the presence of human AGA activity and their human chromosomal constitutions. Without exception, the presence of human AGA in these hybrids was correlated with the presence of human chromosome 4. All other human chromosomes were excluded by discordant segregation of the human enzyme and other chromosomes. Two hybrid clones, with interspecific Chinese hamster-human chromosome translocations involving the long arm of human chromosome 4, permitted the assignment of human AGA to the region 4q21----4qter.  相似文献   

18.
Severe combined immunodeficient (SCID) mice engrafted with human peripheral blood leukocytes (hu-PBL-SCID) represent a potentially important small animal model for the study of human immune function. Attempts to generate human primary immune responses to exogenous Ag in the hu-PBL-SCID have had limited success which raises questions about the functional capacity of human lymphocytes in the SCID environment. Here, we demonstrate that the spontaneously secreted human Ig in hu-PBL-SCID includes antibodies with specificity for several different mouse RBC (mRBC) proteins. These antibodies apparently reflect the transfer of peripheral B cells which are responsible for the production of naturally occurring xenoreactive antibodies in the donor. Western blot analysis showed that engraftment of anti-mRBC specificities was random among mice receiving PBL from the same donor sample. In at least one mouse, this engraftment was polyclonal and included human IgM and IgG which recognized at least 12 different mRBC proteins ranging in size from 35 to > 200 kDa. Anti-mRBC specificities were found to vary with time demonstrating a dynamic expression of the human xenoreactive repertoire in hu-PBL-SCID. In contrast to mice engrafted with human PBL, mice engrafted with another source of human B cells, i.e., tumor-infiltrating leukocytes, produced very little or no human anti-mRBC antibody. Ag-driven proliferation of xenoreactive clones may result in a skewing of the engrafted human B cells in hu-PBL-SCID which could account in part for the limited ability of hu-PBL-SCID to respond to exogenous Ag. The long term production of anti-mRBC antibodies and the modulation of the expressed xenoreactive repertoire observed in hu-PBL-SCID represents an opportunity to study the molecular genetics and cell biology of the human humoral immune response to a defined complex Ag.  相似文献   

19.
Human cystatin, a new protein inhibitor of cysteine proteinases   总被引:8,自引:0,他引:8  
A new low-molecular weight protein inhibitor of cysteine proteinases, human cystatin, was isolated from sera of patients with autoimmune diseases. It inhibits papain, human cathepsin H and cathepsin B. According to its partially determined amino-acid sequence, human cystatin is highly homologous to egg white cystatin, but only distantly related to stefin, the cytosolic protein inhibitor of cysteine proteinases isolated from human polymorphonuclear granulocytes. Very probably human cystatin is identical with human gamma-trace, a microprotein of known sequence but hitherto unknown function.  相似文献   

20.
本文采用双积分球测量系统和Inverse Add ing-Doub ling方法,研究了自然和热凝固的人肝组织对532nm的KTP激光和1 064 nm的Nd:YAG激光的光学特性。结果表明:热凝固的人肝组织对532 nm的KTP激光的吸收系数较自然的肝组织的吸收系数增大了23.5%(P<0.05),热凝固的肝组织对1 064 nm的Nd:YAG激光的吸收系数较自然的肝组织的吸收系数减小了34.3%(P<0.05)。热凝固的人肝组织对532 nm的KTP激光的散射系数较自然的肝组织的散射系数增大了4.50倍(P<0.05),热凝固的肝组织对1 064 nm的Nd:YAG激光的散射系数较自然的肝组织的散射系数增大了6.41倍(P<0.05)。热凝固的人肝组织对532 nm的KTP激光的各向异性因子较自然的肝组织的各向异性因子减小了5.47%,热凝固的肝组织对1 064 nm的Nd:YAG激光的各向异性因子较自然的肝组织的各向异性因子减小了1.95%。  相似文献   

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