重组人sCR1多克隆抗体制备及纯化鉴定

目的制备原核表达人sCR1多克隆抗体并对其进行鉴定。方法提取人总RNA进行RT-PCR扩增合成cDNA,以cDNA为模板,构建重组表达质粒pET28a-sCR1。在大肠杆菌中表达人sCR1融合蛋白作为免疫原制备兔多抗。采用ELISA法检测抗体效价,免疫亲和层析法纯化后,进行SDS-PAGE鉴定分析。结果sCR1表达融合蛋白免疫家兔制备的兔抗人sCR1多克隆抗体,可特异地识别人sCR1融合蛋白。结论纯化复性后的sCR1融合蛋白作为抗原免疫家兔,有较好的抗原性和免疫原性,成功地制备出兔抗人sCR1多克隆抗体,并有较高的效价及特异性。为进一步大量表达纯化及临床免疫学检测方法的键立奠定了基础。     

重组人转化生长因子β1原核表达及多克隆抗体制备

目的克隆人转化生长因子β1(TGF-β1)基因,原核表达TGF-β1蛋白,制备兔抗人TGF-β1多克隆抗体。方法应用RT-PCR技术扩增人TGF-β1基因序列,构建pET-28a-TGF-β1重组质粒。转化至E.coli BL21(DE3)中,异丙基-β-D-硫代吡喃半乳糖苷(IPTG)诱导表达。Western-blot检测目的蛋白的抗原性。免疫新西兰白兔,获得兔抗人TGF-β1多克隆抗血清。饱和硫酸铵盐析法纯化多克隆抗体,间接ELISA法检测多克隆抗体效价,Western-blot技术进行抗体特异性检测。结果获得了TGF-β1编码序列和表达载体,目的蛋白主要存在于超声破碎后的包涵体中;经Western-blot检测目的蛋白存在抗原性;获得纯化的兔抗人多克隆抗体效价达1∶10 000。结论获得的兔抗人TGF-β1多克隆抗体效价较高,具有良好的特异性。     

艰难梭菌毒素C蛋白的克隆表达和抗体制备

目的克隆艰难梭菌毒素C(tcdC)基因并构建TcdC蛋白的原核表达载体,制备多克隆抗体。方法从艰难梭菌标准株(ATCC43255)基因组DNA中扩增获得tcdC基因的部分片段,连接到原核表达载体并转化到大肠杆菌中,诱导表达GST-TcdC/L和IL1-TcdC/L融合蛋白,前者用作免疫抗原,后者用作检测抗原。采用SDS-PAGE法鉴定融合蛋白的表达,并通过Ni柱纯化IL1-TcdC/L融合蛋白,Q柱纯化GST-TcdC/L融合蛋白。将纯化的GST-TcdC/L融合蛋白于兔背部皮内多点注射,每只1 mg,4周1次,共3次。最后1次免疫后2周,采血分离血清。用IL1-TcdC/L蛋白包被酶联板,采用ELISA法检测多抗血清效价;Western蛋白印迹法检测多抗特异性,结果 SDS-PAGE结果表明,所表达的2个融合蛋白与预期分子质量一致。ELISA结果显示,制备的TcdC多克隆抗体效价>1:6.4×10~4。Western蛋白印迹实验显示,制备的TcdC/L多克隆抗体能特异性识别艰难梭菌中的TcdC蛋白。结论成功克隆了艰难梭菌tcdC/L基因并进行了原核表达,成功制备了其多克隆抗体,为后续研究tcdC基因在艰难梭菌致病过程中的作用及机制奠定了基础。     

心脏型脂肪酸结合蛋白(H-FABP)原核表达、纯化及多克隆抗体制备研究

目的构建H-FABP高效原核表达载体,并实现H-FABP的高效原核表达、纯化及多克隆抗体的制备。方法通过RT-PCR扩增人H-FABP的基因序列,将目的基因克隆入质粒pET28a构建原核表达重组质粒pET28a-H-FABP。将重组质粒转化入大肠杆菌BL21中,通过IPTG诱导H-FABP的表达,采用Q Sepharose F.F.阴离子层析柱等方法建立H-FABP的纯化工艺。用免疫胶体金法和Western blot鉴定纯化后重组蛋白免疫特异性,用重组表达蛋白制备兔抗H-FABP多克隆抗体。结果成功构建人H-FABP重组蛋白原核表达载体,重组蛋白以包涵体形式表达,其相对分子质量为15kD,与预期一致。亲和层析纯化产物的SDS-PAGE和Western blotting鉴定表明获得纯度>95%的目的重组蛋白。制备的抗H-FABP多克隆抗体的抗血清ELISA效价可达1∶512000。结论本研究在原核系统中成功表达了H-FABP重组蛋白,并制备多克隆抗体,为H-FABP的结构和功能研究及开发临床诊断试剂盒打下了基础。     

肝癌相关基因HTA的重组表达及多克隆抗体的制备

目的将肝癌相关基因HTA进行克隆、表达并制备多克隆抗体,为进一步研究其作为肝癌导向治疗靶点的可行性及临床意义奠定基础。方法应用RT-PCR技术,从人肝癌细胞系HepG2细胞中扩增得到HTA3＋cDNA,再将其克隆到原核表达载体pET21a（＋）-MBP内,用IPTG诱导其在大肠杆菌BL21（DE3）中表达。His-tag磁珠纯化试剂盒纯化重组蛋白MBP-HTA,通过Westernblot和ELISA方法检测重组蛋白的抗原性。将纯化的重组蛋白免疫BALB／c小鼠制备多克隆抗体,并采用ELISA、Westernblot和免疫组化的方法检测抗体的灵敏度和特异性。结果成功地构建了表达MBP-HTA融合蛋白的原核表达质粒pET21a（＋）-MBP-HTA。重组MBP-HTA融合蛋白在大肠杆菌BL21（DE3）内得以高效表达,且以包涵体的形式存在。His-tag磁珠纯化试剂盒纯化和Westernblot分析,得到了分子量约为52kDa的目的蛋白。获得了高效价的特异性多克隆抗体,经ELISA检测抗体的效价为1：3200。用Westernblot检测的效价为1：400。免疫组织化学检测表明：肝癌组织中HTA蛋白的阳性表达率明显高于正常肝组织俨〈0．01）。结论成功地制备出抗MBP-HTA多克隆抗体,该抗体有较高的效价和特异性;能用于免疫组织化学的检测,且HTA在肝癌组织中的阳性表达率明显高于正常肝组织。HTA蛋白有望成为肝癌导向治疗的潜在靶点。     

谷胱甘肽-S转移酶-中期因子融合蛋白原核表达及多克隆抗体的制备

目的 构建谷胱甘肽-S-转移酶(GST)和中期因子(MK)融合蛋白的原核表达质粒,并表达和纯化蛋白,制备多克隆抗体.方法 通过RT-PCR技术从人胃癌组织中扩增入MK编码序列,克隆入表达载体pGEX-1λT中,获得表达质粒pGEX-MK,并在大肠杆菌BL21 (DE3)中经IPTG诱导表达,通过亲和层析纯化表达的GST-MK融合蛋白,并以重组蛋白免疫兔子.结果 成功构建了GST-MK融合蛋白的原核表达载体,经诱导表达纯化得到GST-MK融合蛋白.免疫兔子后取多抗血清以间接ELISA检测效价达1∶64 000,Western blotting分析显示多克隆抗血清对MK蛋白特异结合.结论 MK在大肠杆菌中成功表达及其多克隆抗体的获得,为研究MK生物功能奠定了基础.     

以CpG为佐剂的人IL-24多克隆抗体的制备

目的：采用在原核表达系统表达的人IL-24蛋白及人IL-24真核重组质粒免疫新西兰兔，制备兔抗人IL-24多克隆抗体。方法：利用IPTG诱导hIL-24在大肠杆菌中表达，纯化hIL-24重组蛋白，纯化后的蛋白经SDS—PAGE分析，同时提取hIL-24真核重组质粒，用以免疫新西兰兔，并以CpG为佐剂制备多克隆抗体。Western-blot鉴定抗体的特异性，ELISA法测定抗体效价。结果：人IL-24经IPTG诱导后可在大肠杆菌中大量表达，表达量占细菌总蛋白的30％，纯化后的蛋白纯度高；原核表达的重组蛋白和真核重组质粒免疫新西兰兔，通过抗体效价测定，获得了抗血清效价达1：640的多克隆抗体。结论：原核表达的hIL-24蛋白和hIL-24真核重组质粒均能刺激家兔产生抗体．其多克隆抗体的效价较高。     

Fas胞外区基因的构建、表达、纯化及多克隆抗体的制备

目的构建Fas胞外区(eFas)基因的表达载体,表达纯化重组蛋白,进行多克隆抗体的制备,为进一步功能研究奠定基础。方法通过重叠PCR获得eFas基因的编码序列,构建pET-22b(+)/eFas表达载体,转化大肠杆菌Rosetta-gami,IPTG诱导表达,Ni-NTA柱亲和纯化,SDS-PAGE鉴定重组蛋白的纯度。将纯化的eFas融合蛋白免疫新西兰白兔制备多克隆抗体,通过ELISA方法检测多克隆抗体的效价。结果获得了eFas的编码序列与表达载体,目的蛋白主要在包涵体中表达,表达量占菌体总蛋白的30%以上,纯化的重组蛋白纯度达95%以上。结论eFas融合蛋白基因的构建、表达、纯化以及多克隆抗体的制备,为进一步研究Fas提供了材料。     

抗空肠弯曲菌外膜蛋白PEB1多克隆抗体的制备与鉴定

目的 表达空肠弯曲菌外膜蛋白PEB1,并制备针对该蛋白的多克隆抗体.方法 诱导培养工程菌E coli BL21 (DE3)表达空肠弯曲菌PEB1重组蛋白.经镍-琼脂糖凝胶亲和层析柱纯化,透析并定量后,常规免疫新西兰兔.收集血清,盐析法粗提IgG,应用间接ELISA法和双向琼脂扩散试验检测抗体效价,并通过Western blot和玻片凝集试验检测抗体的特异性.结果 得到高纯度的空肠弯曲菌PEB1重组蛋白.用该蛋白免疫新西兰兔后,获得抗PEB1多克隆抗体.间接ELISA法检测抗体效价为1:2×104,双向琼脂扩散试验检测抗体效价为1:8.结论 运用纯化的空肠弯曲菌PEB1重组蛋白免疫新西兰兔,获得高效价的多克隆抗体.     

柯萨奇病毒A组5型VP1蛋白原核表达及多克隆抗体的制备

目的 原核表达柯萨奇病毒A组5型(coxsackievirus A5,CV-A5)VP1蛋白,并制备抗VP1多克隆抗体(多抗),为CV-A5相关定性定量研究制备试剂。方法 逆转录PCR扩增N端截短的CV-A5VP1-ΔN56后,克隆至原核表达载体pGEX-6P-1,获得pGEX-6P-1-VP1-ΔN56。将其转化大肠埃希菌BL21(DE3),表达重组蛋白并纯化。用纯化的谷胱甘肽巯基转移酶-VP1-ΔN56融合蛋白经背部皮下免疫日本大耳白兔,制备多抗。结果 重组表达载体构建成功,融合蛋白以不可溶包涵体存在。ELISA、蛋白质印迹法检测表明,获得的兔多抗效价为107,可特异性识别重组和天然CV-A5 VP1蛋白。结论 成功制备重组CV-A5 VP1蛋白及特异性多抗。为中和抗原表征研究及VP1定性定量分析奠定了基础。     

Identifying body residues of HCBP associated with 10-d mortality and partial life cycle effects in the midge, Chironomus riparius

The relationship between the body residue of 2,2',4,4',5,5'-hexachlorobiphenyl (HCBP) and its effects, including 10-d mortality and chronic sublethal effects on the midge, Chironomus riparius, are examined in a partial life cycle assessment. The alga, Chlorella vulgaris, was loaded with 14C-labeled HCBP and fed to midges as the method for delivery of the toxicant. In a 10-d bioassay, median lethal body residue (LR50) was 0.57 (95% CI: 0.49-0.66) mmol/kg. In the partial life cycle test, midges were fed a mixture of 12C- and 14C-HCBP-laden algae and exposed in four separate tests to assess the different developmental stages representing 2nd to 3rd instar, 2nd to 4th, 2nd to pupa, and 2nd to adult stages. A variety of sublethal endpoints were monitored, including developmental time within a stadium, body concentration at the end of each stadium, body weight, and fecundity (the number of ova) for the female pupae and adults. Overall, midge body concentrations of HCBP increased with increasing exposure concentration. Body weight was not significantly affected by HCBP except during the 4th instar. Body residue also increased with each successive stadium. Developmental time increased significantly with increasing body concentration in 2nd to 4th, 2nd to pupa, and 2nd to adult tests, while there was no statistical significance in developmental time for the 2nd to 3rd instar test. The number of ova decreased significantly in adults with increasing body concentration of HCBP, with an average of 345 ova in controls, 289 ova at 0.028 mmol/kg of HCBP, and 258 ova at 0.250 mmol/kg. These data, which relate chronic endpoints to body residues, suggest that sublethal endpoints in invertebrates are useful for defining sublethal hazards of PCBs. These data also suggest that ecological consequences may result from relatively low body burdens of PCBs.     

Isolation and structure elucidation of 12beta-acetoxycoccinic Acid, 12beta-hydroxycoccinic Acid, 12alpha-acetoxycoccinic Acid, and 12alpha-hydroxycoccinic acid1

Four new triterpenoid acids, possessing a lanost-9(11)-en-3-one skeleton, were isolated from KADSURA HETEROCLITA. Based on chemical and spectral analyses, they were assigned as 12beta-acetoxycoccinic acid, 12beta-hydroxycoccinic acid, 12alpha-acetoxycoccinic acid, and 12alpha-hydroxycoccinic acid.     

Pharmacokinetic profile of loprazolam in 12 young and 12 elderly healthy volunteers

The aim of the study was to investigate the pharmacokinetic profile of acute and steady state doses of loprazolam (1 mg) following nighttime administration in 12 young (18-30 years) and 12 elderly (60-80 years) nonfasting subjects. Loprazolam blood plasma concentration was determined by high-performance liquid chromatography with ultraviolet absorption detection. The drug was isolated from the plasma using a solid phase extraction procedure. On day 1 subjects were breathalyzer and given a brief medical examination. Baseline blood samples (10 ml) were taken via a venous cannula at -1.5 to -0.25 h prior to drug administration. Loprazolam was administered at 21.00 and further blood samples were taken at 0.5, 1, 1.5, 2.0, 2.5, 3, 4, 5, 6, 8, 10, 12, 18 and 23.5 h (baseline sample for day 2). On subsequent days (days 2, 3 and 4) blood samples were taken at -0.5 and 2 h. The schedule for day 1 was repeated for day 5 with the test period ending at 21.30 on day 6. Significant changes in the pharmacokinetics of the drug were evident in the elderly volunteers compared with the young volunteers following steady state, where tmax was significantly prolonged (CI 90% = 0.80 to 1.25; p < 0.00006) and a decline was observed in peak plasma concentration (CI 90% = 0.80 to 1.25; p < 0.00006). However, no statistically significant difference was found between the two groups in either the elimination half-life of the drug or the area under the curve. Loprazolam appears to be well tolerated by both the young and the elderly and only mild adverse effects were reported after nighttime administration. These results provide valuable data on the pharmacokinetics of the drug in normal clinical practice.     

Interleukin-12 and photocarcinogenesis

UV radiation induces immunosuppression and inflammatory responses, as well as oxidative stress and DNA damage, in skin cells and these various effects have been implicated in melanoma and nonmelanoma skin cancers, i.e., photocarcinogenesis. The cytokine interleukin (IL)-12 has been shown to possess potent antitumor activity in a wide variety of murine tumor models. In this review, we summarize the evidence that IL-12 plays a role in preventing photocarcinogenesis, and present a model of its possible mechanisms of action. Treatment of mice with IL-12 prevents UV-induced immunosuppression in a process mediated by repair of UV-induced damaged DNA. After exposure to the photocarcinogenesis protocol, the development of UV-induced tumors is more rapid and the tumor multiplicity and tumor size are significantly greater in IL-12-deficient or knockout (KO) mice than their wild-type counterparts. IL-12-deficiency in mice enhances the proliferation potential of tumor cells, and this may be one of the reasons for the rapid growth of the tumors and their greater size. The rate of malignant transformation of UV-induced papillomas to carcinomas also is higher in the IL-12 KO mice than in their wild-type counterparts in terms of carcinoma incidence and carcinoma multiplicity. UV-induced DNA damage in the form of cyclobutane pyrimidine dimers (CPDs) and sunburn cells is lower, or repaired more rapidly, in wild-type mice than IL-12 KO mice. The IL-12-associated reduction in UV-specific CPDs is due to induction of DNA repair, and particularly enhancement of nucleotide-excision repair. We suggest that endogenous stimulation of IL-12 may protect the skin from UV-induced immunosuppression, DNA damage, and, ultimately, the risk of photocarcinogenesis. Taken together, this information suggests that augmentation of IL-12 should be considered as a strategy for the prevention and treatment of photocarcinogenesis.     

Covalent linkage of IL-12 and ovalbumin confines the effects of IL-12 to ovalbumin-specific immune responses

In order to direct the form of the immune response in an antigen-specific manner, we constructed a fusion protein (OVA/IL12) that contained the T cell-dependent antigen, ovalbumin (OVA), covalently linked to murine interleukin-12 (IL-12). The OVA/IL12 protein was produced in a baculovirus expression system and was purified by anti-OVA immunoaffinity chromatography. The purified OVA/IL12 protein displayed potent IL-12 bioactivity in an IL-12 proliferation assay. BALB/c mice immunized with the OVA/IL12 protein produced increased quantities of anti-OVA IgG2a antibody compared with mice immunized with recombinant OVA alone. Lymph node cells from the immunized mice with the OVA/IL12 protein produced large amounts of IFN-gamma when restimulatedin vitro with OVA, while those from mice immunized with the OVA protein produced little or no IFN-gamma. In contrast, immunization with a mixture of OVA and free recombinant IL-12 also induced IFN-gamma production, which was not OVA-specific. These studies indicate that the OVA/IL12 fusion protein can induce OVA-specific, Th1-dominated imnune responses, and that the covalent linkage of OVA and IL-12 confines the effect of IL-12 to OVA-specific cells.