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1.
重组人白细胞介素—2在离子色谱分离时的复性   总被引:1,自引:0,他引:1  
采用HPIEC应用CM交换柱分离纯化E.coli工程菌表达的rIL-2,与空气氧化复性相比较,又有1倍以上的变性rIL-2在色谱过程中得到复性,且溶液pH影响rIL-2的复性和纯化效果:pH7.0时rIL-2复性率高于pH8.0时,但纯度明显低于pH8.0时分离的rIL-2。  相似文献   

2.
用单抗研究白细胞介素2的结构功能和抗原性   总被引:1,自引:0,他引:1  
利用多价抗体及一组单克降抗体(McAb)研究了人重组白细胞介素2(rIL-2)的功能域和抗原性。中和试验表明:rIL-2N端(1~28)的McAb具有明显中和IL-2活性,而中区(59~72)和C端(105~133)的McAb则无此功能。排阻ELISA证实:rIL-2的N端与中区接近,并共同构成一个表位(2A9);C端回折紧靠中区,但在N端对侧,且与中区的距离较N端更近。抗原性分析确定了4个显型表位(1~19、45~54、59~72、105~B3)及2个隐型表位(20~44、74~88)。  相似文献   

3.
采用HPIEC应用CM交换柱分离纯化E.coli工程菌表达的rIL-2,与空气氧化复性相比较,又有1倍以上的变性rIL-2在色谱过程中得到复性,且溶液pH影响rIL-2的复性和纯化效果:pH7.0时rIL-2复性率高于pH8.0时,但纯度明显低于pH8.0时分离的rIL-2.  相似文献   

4.
用自制的氨基PEG化试剂rIL-2进行化学修饰,研究了试剂浓度,溶液pH,反应时间等与PEca-rIL-2产率及IL-2活性保持之间的关系,建立了一套获得稳定修饰度的PEG-rIL-2的方法。研究发现,反应时间跟修饰度关系不大;溶液pH对修饰度有一定的影响,中性pH以上反应都可进行;而试剂浓度直接决定修饰度的高低,过量越多,修饰度越高,而生物活性保留也越低;但低度修饰,对活性几乎没有影响,可保留活性在95%左右。  相似文献   

5.
常远  唐微 《生物化学杂志》1996,12(4):445-449
用自制的氨基PEG化试剂rIL-2进行化学修饰,研究了试剂浓度,溶液pH,反应时间间等与PEG-rIL-2产率及IL-2活性保持之间的关系,建立了一套获得稳定修饰度的PEG-rIL-2的方法,研究发现,反应时间跟修饰度关系不大;溶液pH对修饰度有一定的影响,中性pH以上反应都可进行;而试剂浓度直接决定修饰度的高低,过量越多,修饰度越高,而生物活性保留也越低;但低度修饰,对活性几乎没有影响,可保留活  相似文献   

6.
表达的白细胞介素-2-绿脓杆菌外毒素(IL-2-PE)融合蛋白以包含体形式存在于宿主菌中,为分离纯化表达产物提供了方便,但因需进行复性,也增加了后处理的难度.我们采用4mol/L尿素、0.5%TritonX-100的1×PBS洗涤包含体两遍,再经SephacrylS-300分子筛及DEAE-SepharoseFF阴离子交换柱层析后,获得的融合蛋白纯度可达90%~95%。此外,我们从GSSG浓度、L-精氨酸浓度、复性蛋白质的起始浓度、复性液的pH值、复性温度及复性时间等参数入手,系统地研究了融合蛋白的复性条件,探索到了IL-2-ME40和IL-2-PE664Glu融合蛋白复性的最适条件。  相似文献   

7.
PEG化蛋白质的分离纯化比较困难,本工作发现PEG化蛋白质仍能被硫酸铵盐析,据此可以简单地将IL-2及PEG化IL-2沉淀出来,而将有毒的活化PEG等副产物留在溶液中。此方法效果理想而又十分简便。文献中未见报道。此外,实验还发现,在PEG-IL-2与IL-2的混和液中加入一定量的PEG后,二者之间溶解度差别增大,当用SephacryⅠS-200柱分离时,先用含10%PEG,0.25mol/LNaCl的缓冲液平衡洗脱PEG-IL-2,再降低盐浓度洗下IL-2,即可使二者完全分开。过去要将IL-2与PEG-IL-2分离开非常困难,本工作解决了这个问题,这点亦未见文献报道。  相似文献   

8.
利用脑炎心肌炎病毒和脊髓灰质灰病毒的内核糖体进行位点,连接人TNF-α及IL-2cDNA和选择基因新霉素磷酸转移酶基因(NeoR),使TNF-α、IL-2及NeoR基因均受控于病毒毒LTR启动子,将这3个基因转录至用一mRNA,从而构建成含人TNF-α、IL-2及NeoR基因多顺反子逆转录病毒载体pGCEN/TRI。在LipofectAMINE介导下将其导入包装细胞PA317,G418筛选得单克隆  相似文献   

9.
人白细胞介素—2基因在人骨肉瘤细胞系内表达   总被引:1,自引:0,他引:1  
从pHIG53质粒内切下人白细胞介素-2cDNA基因,并经中间一pSP72转换成与pDOR-neo载体相区域的酶切位点,然后将IL-2cDNA定向连接入pDOR-neo载体,构建成功人IL-2逆转录病毒载体,经脂质体民入人骨肉瘤细胞系Ma中,经G418筛选后测转基因肿瘤细胞培养上清中IL-2表达量,每1×10^5细胞24hIL-2表达量为50-800U,为骨肉瘤的基因治疗创造条件。  相似文献   

10.
用凝胶阻滞分析的方法,发现鼠T淋巴细胞系CTLL-2在白细胞介素-2(IL-2)刺激下可活化一个结合因子,它与γ-干扰素活了列(GAS)专一性结合,命名这个DNA结合因子为白细胞介素-2活化核因子(IL-2-NAF),IL-2-NAF的活化非常迅速,不需要新的蛋白质合成,并且它的活化程度随着IL-2刺激细胞的时间的不同而发生相应的变化,进一是步研究表明,IL-2-NAF的活化过程是通过酪氨酸激酶的  相似文献   

11.
In adoptive immunotherapy, the number of effector cells is one of the major factors relating to the therapeutic efficacy. We demonstrated that tumor-infiltrating lymphocytes (TILs) were stimulated to proliferate by incubation with interleukin 2 (IL-2) plus interleukin 4 (IL-4). TILs cultured with IL-2 plus IL-4 increased 3.1-fold more than TILs cultured with IL-2 alone. However, IL-4 did not alter the cytotoxic activity of TILs against autologous tumor cells and established tumor cell lines. It is suggested that IL-2 receptor is related to the mechanism of the proliferation of activated TILs cultured by combination with IL-2 and IL-4. Thus, the combination of IL-2 and IL-4 may increase the efficacy of adoptive immunotherapy using activated TILs.  相似文献   

12.
目的 :观察乳腺癌MCF 7细胞上白细胞介素 2受体 (IL 2R)α、β和γ链的表达、IL 2对MCF 7细胞增殖的作用及雌激素对三条链表达的影响。方法 :使用特异性IL 2R多克隆抗体以免疫细胞化学方法和流式免疫荧光法检测MCF 7细胞上IL 2R的表达 ,以MTT法及3 H TdR掺入法检测细胞增殖情况。结果 :MCF 7细胞上存在IL 2Rα、β、γ的免疫阳性物质 ,其中IL 2Rγ的表达要强于IL 2Rα、β的表达 ;10 -6mol/L浓度的雌二醇可促进IL 2Rα、β的阳性细胞数及IL 2Rγ的免疫阳性物质的含量 ;IL 2在 10 0U/ml至 10 0 0U/ml的浓度范围内可显著促进MCF 7细胞的增殖。结论 :MCF 7细胞上存在IL 2R且其表达受雌二醇的调节 ,IL 2可能通过IL 2R影响MCF 7细胞的增殖  相似文献   

13.
de Jong JL  Farner NL  Sondel PM 《Cytokine》1998,10(12):920-930
More interleukin 15 (IL-15) than IL-2 was needed to generate comparable proliferative responses by phytohaemagglutinin (PHA) blasts and Tf-1beta cells expressing high affinity and intermediate affinity IL-2 receptor (IL-2R) complexes, respectively. The focus of these experiments was to determine the contribution of the shared IL-2 and IL-15 receptor components to these dose-response differences. Some of this difference can be attributed to the role of the IL-2Rbeta chain, in that HuMikbeta1, a monoclonal antibody recognizing the IL-2Rbeta chain, blocks 92.2+/-2.5% (mean+/-SE) of the IL-2 proliferative response by Tf-1beta cells but only inhibits 57.9+/-3.7% of the IL-15 response, indicating that IL-2 and IL-15 may physically utilize the IL-2Rbeta chain differently. Monoclonal antibody 341, which recognizes IL-2Rbeta but does not inhibit IL-2 binding to the IL-2Rbeta chain, blocks 35.4+/-2.3% of IL-15-stimulated proliferation of PHA blasts, while not affecting the IL-2-stimulated proliferation. Finally, although HuMikbeta1 does not inhibit IL-2 responses by PHA blasts bearing high affinity IL-2 receptors, HuMikbeta1 does block IL-15-stimulated proliferation by these same cells bearing high affinity IL-15 receptors (88.5+/-1.6% inhibition). This indicates that the role of IL-15Ralpha in the high affinity IL-15R complex is distinct from that of IL-2Ralpha in the high affinity IL-2R complex. Overall, these studies show that the physical interactions of the IL-2Rbetagammac complex with IL-2 are different than the interactions with IL-15.  相似文献   

14.
In this report, we have examined whether (6R)-tetrahydrobiopterin (H4biopterin) modulates the binding of interleukin 2 to high-affinity sites of the cloned mouse cytotoxic T-lymphocyte clone CTLL-2. Scatchard plot analysis of the equilibrium binding data reveals increased affinity when the cells are exposed simultaneously to interleukin 2 and to the pterin. The Kd values are statistically significantly reduced from 1.4 x 10(-11) M to 0.78 x 10(-11) M interleukin 2. The dissociation kinetics of the ligand were followed at 4 degrees C after equilibrium binding under high-affinity conditions (1.2 x 10(-10) M interleukin 2). In the presence of H4 biopterin, the dissociation rate constant (k-1) decreases from 6.2 x 10(-3) min-1 to 3.0 x 10(-3) min-1 and the half-time for dissociation increases from 106.8 min to 218.0 min. As a third approach interleukin 2 was bound to the surface of cells under high-affinity conditions by incubation in the cold and the internalization kinetics upon warming were determined. Sigmoidal-shaped kinetics of endocytosis in control cells indicate that the internalization rates increase only gradually. The presence of H4 biopterin causes an apparent immediate transition from higher-order kinetics to a linear response so that maximum internalization rates are reached immediately upon warming. The data show that lymphocyte-derived H4 biopterin in vitro at concentrations ranging from 2-8 x 10(-7) M modulates interleukin 2 high-affinity binding and that H4 biopterin potentially participates in the control of interleukin 2 receptor assembly.  相似文献   

15.
白细胞介素-2对心脏节律的作用及其机制的研究   总被引:1,自引:0,他引:1  
目的:探讨白细胞介素-2(1L-2)对心脏节律作用及其可能机制。方法:采用体外培养乳鼠心肌细胞模型和离体人鼠灌流心脏模型,观察培养的心肌细胞搏动频率和离体心脏心率及节律。结果:①2.5-200u/ml的IL-2呈浓度依赖性地降低心肌细胞的搏动频率。②50u/ml的IL-2明显增加离体心脏心率和室性早搏个数。③propranolol预处理可取消50u/mlIL-2的离体心脏作用。④热失活IL-2对培养的心肌细胞搏动频率和离体心脏心率和心律都无显著作用。结论:IL-2可直接制培养心肌自律性,其对离体心脏的正性变时和致心律失常作用可能由内源性作茶酚胺介导。  相似文献   

16.
Cell kinetic studies of T cells stimulated with the interleukin 2 (Il-2), Il-4, or both lymphokines were performed with conventional [3H]thymidine incorporation and with the bivariate BrdU/Hoechst technique. Il-2 and Il-4 are able to drive phytohemagglutinin-activated T cells through more than one cell cycle. Neither synergistic nor inhibitory effect on T-cell proliferation was seen for the stimulation with both Il-2 and Il-4 as compared with the effect of Il-2 alone. The quantitative data of the cell cycle distribution of phytohemagglutinin-activated T cells suggest that the population of Il-4-responsive cells is at least an overlapping population, if not a real subset of the population of the Il-2-responsive cells.  相似文献   

17.
It has been postulated that favouring the absorption of interleukin-2 via lymphatics rather than venous capillaries after subcutaneous adminstration may improve its therapeutic index. We have now evaluated in 12 cancer patients the plasma pharmacokinetic of interleukin-2 either dissolved in water or in 20% albumin solution with an internal cross-over after at least three days. Our data show that when albumin is present, the plasma concentrations of interleukin-2 versus time is increased and swelling at the injection sites is reduced. It remains to be seen whether efficacy improves during a prolonged treatment.Abbreviations AUC Area Under Plasma Curve - BRM Biological Response Modifiers - IFN Interferon - IL-2 Interleukin-2 - IV Intravenous - SC Subcutaneous - MU Megaunit  相似文献   

18.
Interleukin 2 (IL 2) is a polypeptide growth factor essential for the proliferation and differentiation of T lymphocytes, large granulocytic lymphocytes, and, potentially, cells of the antibody-producing lineage, B lymphocytes. Many of the biological properties of IL 2 may be mimicked or potentiated by a potent class of tumor promoters, phorbol esters. Phorbol esters have recently been shown to associate with and activate a unique phospholipid/Ca2+-dependent phosphotransferase, protein kinase C (PK-C). Utilizing two-dimensional gel electrophoresis, we have compared the IL 2 and diacylglycerol-induced protein phosphorylation patterns of several IL 2-dependent murine cell lines. Both IL 2 and synthetic diacylglycerol, 1-oleyl-2-acetylglycerol (OAG), stimulated phosphorylation of a number of protein substrates in intact cells compared to unstimulated controls. Three groups of substrates were identified; the first showed increased phosphorylation following stimulation with either IL 2 or OAG, while the second and third groups showed increased phosphorylation following stimulation with IL 2 but not OAG, and with OAG but not IL 2, respectively. Here, we characterize the kinetics of phosphorylation of one cellular substrate, p68, which appears to be phosphorylated in response to direct activators of PK-C or lymphoid or myeloid growth factors in their respective lineage cell lines. The observation that IL 2 also stimulates a unique series of phosphoproteins in addition to those induced by direct PK-C activators suggests that IL 2 may initiate additional protein kinase activities, unrelated to PK-C, which may also be critical for the ligand-receptor signal transduction process regulating growth and gene expression.  相似文献   

19.
Studies were conducted to characterize a HeLa cell model by which the roles of the 85-kDa phospholipase A2 (cPLA2) in interleukin-1 beta (IL-1 beta) and interleukin-6 (IL-6) release could be evaluated. At first, untreated HeLa cells were compared with lipopolysaccharide (LPS)-treated HeLa cells. The latter resulted in cPLA2 overexpression and an increased trend of IL-1 beta and IL-6 release. The indicated doses of 85-kDa cPLA2 antisense oligonucleotide directed against the initiation site were then used to block cPLA2 in LPS-induced HeLa cells. The process led to a dose-dependent decrease in cPLA2 protein with no noticeable change of cPLA2 mRNA. Compared with that of LPS added only, a reduction of IL-1 beta and IL-6 levels in the supernatants of transfected cells following the repression of cPLA2 was observed. These results suggested that 85-kDa cPLA2 may mediate the signalling cascades by which IL-1 beta and IL-6 were released in LPS-induced HeLa cells.  相似文献   

20.
促炎因子在心脏修复中的作用   总被引:1,自引:0,他引:1  
肿 瘤 坏死 因 子 TN F)、白介 素 -1(IL-1)、白 介 素 -2(IL-2)以 及 白介 素 -6(IL-6)等 分子 ,叫 作 促 炎细 胞 因 (子 .一 般 认为 它 们不 属于 免 疫系 统,而 只是 与 组织 炎症 的起 始 有关 .促 炎因 子在 心 脏中 也 有表 达,它 的短 期表 达可 以 帮助 心 脏适 应外 界 压力 的损 伤 ,而其 长期 的 表达 却会 引 起明 显的 心 脏代 谢失 常 .主要 就 促炎 因子 在心 脏中 的 作用 作 一综 述 .  相似文献   

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