兔抗小鼠IL-23p19多克隆抗体的制备和鉴定

目的制备兔抗小鼠白细胞介素23p19(IL-23p19)多克隆抗体。方法利用分子克隆技术构建重组表达质粒p ET-16b-IL-23p19,转化大肠杆菌BL21(DE3),异丙基-β-D-硫代半乳糖吡喃糖苷(IPTG)诱导蛋白表达,SDS-PAGE及Western blot法分析鉴定蛋白,镍柱亲和层析纯化制备蛋白;以此蛋白为免疫抗原免疫新西兰大白兔,获得抗血清,并利用亲和层析法纯化抗血清,制备兔抗小鼠IL-23p19多克隆抗体;采用ELISA检测抗体效价;Western blot法检测抗体特异性。结果重组表达载体p ET-16b-IL-23p19构建正确且IL-23p19蛋白能够在大肠杆菌BL21(DE3)中有效表达。通过多次IL-23p19蛋白免疫新西兰大白兔,成功制备兔抗小鼠IL-23p19多克隆抗体。ELISA检测确定新西兰大白兔血清效价达1∶256 000,Western blot法证实兔抗小鼠IL-23p19多克隆抗体能特异性识别小鼠IL-23p19蛋白。结论成功制备了兔抗小鼠IL-23p19多克隆抗体,抗体具有高的效价和较好的特异性。     

含1型血小板结合蛋白基序的去整合素样金属蛋白酶2(ADAMTS2)多克隆抗体的制备

目的原核表达并纯化小鼠源性含1型血小板结合蛋白基序的去整合素样金属蛋白酶2(ADAMTS2)蛋白的C段(1109-1213),制备兔抗ADAMTS2多克隆抗体。方法以重组质粒p GEX-6p-1-ADAMTS2(1109-1213)转化大肠杆菌,异丙基-β-D-硫代半乳糖苷(IPTG)诱导目的蛋白表达,通过亲和纯化,并且经质谱鉴定;以表达的目的蛋白免疫新西兰大白兔,制备抗ADAMTS2的多克隆抗体。ELISA检测抗体效价,Western blot法鉴定抗体特异性。结果在大肠杆菌中表达出目的蛋白ADAMTS2,纯化后经质谱鉴定并免疫新西兰大白兔,成功获得抗血清。血清效价达到1∶160 000以上,且具有良好的特异性。结论成功制备出效价高、特异性好的兔抗ADAMTS2抗体。     

人精子肌动蛋白样蛋白7a蛋白在大肠杆菌系统的表达纯化及多克隆抗体制备

目的 在大肠杆菌系统表达并纯化人精子肌动蛋白样蛋白7a(ACTL7a)的N段(1-70),制备兔抗ACTL7a多克隆抗体.方法 构建重组表达质粒pGEX-6p-1-ACTL7a(1-70),以重组质粒转化E.coli BL21(DE3),筛选阳性重组菌,IPTG诱导目的蛋白表达,通过镍离子金属螯合树脂和谷胱甘肽琼脂糖凝胶4B树脂两次亲和纯化和分子筛分离目的蛋白;以表达的ACTL7a(1-70)蛋白免疫新西兰大白兔,制备抗ACTL7a的多克隆抗体.ELISA检测抗体效价,Western blot法鉴定抗体特异性,免疫荧光组织化学技术检测ACTL7a在曲精小管细胞的表达.结果 经IPTG诱导,在大肠杆菌中表达出目的蛋白ACTL7a(1-70),纯化后免疫新西兰大白兔,成功获得抗血清.血清效价达到1∶160000以上,且具有良好的特异性.结论 成功构建了ACTL7a基因的原核表达载体,并在大肠杆菌中诱导表达,经纯化获得高纯度的目的蛋白;制备出兔抗ACTL7a抗体,效价及特异性均良好.     

AAV9衣壳蛋白VP的原核表达、纯化及多克隆抗体制备

目的：表达腺相关病毒（AAV）9型衣壳蛋白VP,制备抗VP蛋白的多克隆抗体。方法：使用PCR技术从AAV9病毒包装质粒中扩增AAV9衣壳蛋白VP,同源重组法构建衣壳蛋白表达质粒pET30a-AAV9-VP。质粒转化表达菌E.coli BL21(DE3)后,IPTG诱导目的蛋白VP表达,亲和层析法纯化VP蛋白,将纯化后的蛋白免疫日本大耳白兔,3次免疫后获得针对VP蛋白的兔多克隆抗体。以Western blot和细胞免疫荧光法检测抗体的应用,ELISA检测所得抗体的效价。结果：成功构建pET30a-AAV9-VP表达质粒,在大肠杆菌BL21中,IPTG可诱导VP蛋白表达。亲和层析法纯化获得高纯度的VP蛋白。该蛋白在日本大耳兔体内能够诱导产生多克隆抗体,ELISA检测抗血清效价达到1∶512 000。结论：成功原核表达和纯化AAV9衣壳蛋白VP并制备了兔多克隆抗体。制备的抗AAV9 VP抗体能够特异性识别和结合AAV衣壳蛋白,并可有效用于Western blot和细胞免疫荧光分析,为后续深入研究AAV9在基因治疗中的作用及AAV9载体开发提供了研究基础。     

HPV16型E7重组蛋白的表达及其多克隆抗体的制备

目的制备人乳头瘤病毒(HPV)16型E7原核表达蛋白及其多克隆抗体。方法用PCR方法从宫颈癌组织中扩增HPV16 E7基因,克隆至pET21a(+)载体并构建pET21a(+)/HPV16 E7重组质粒,测序鉴定;将重组质粒转化至大肠杆菌BL21(DE3),经异丙基硫代-β-D-硫代吡喃半乳糖苷(IPTG)诱导后表达重组蛋白,用Ni-NTA亲和层析法纯化并经SDS-PAGE及Western blot分析鉴定;纯化的HPV16 E7重组蛋白免疫日本大耳白兔制备多克隆抗体,用ELISA检测多克隆抗体的效价,并用Western blot法及免疫荧光技术分析多克隆抗体的特异性。结果 HPV16 E7重组蛋白可通过原核表达系统进行表达和纯化;通过兔免疫后可制备特异性的多克隆IgG抗体,效价达1∶30 000;经Western blot法和免疫荧光染色结果证实兔多克隆抗体可特异性识别HPV16 E7蛋白。结论成功进行了HPV16 E7原核表达并制备了HPV16 E7兔多克隆抗体。     

结核分枝杆菌PPE68蛋白的表达、鉴定及抗血清的制备

目的在大肠杆菌中表达结核分枝杆菌PPE68蛋白,鉴定并纯化重组rPPE68蛋白后免疫新西兰大白兔,制备兔抗PPE68多克隆抗体。方法将已经过鉴定的重组原核表达质粒pET32a(+)-PPE68转化至大肠杆菌BL21中,IPTG诱导大量表达PPE68蛋白。对表达蛋白进行鉴定后利用亲和层析法进行纯化。以纯化后重组rPPE68为免疫抗原,与弗氏不完全佐剂等体积混合,采用皮下多点注射法免疫新西兰大白兔,于第3次免疫后的第7天采血。用凝集实验与Western-blot检测抗血清的特异性,并用双向免疫扩散法测定抗血清效价。结果在大肠杆菌中表达的目的产物经SDS-PAGE分析,在相对分子质量57 000处可见特异性条带,免疫印迹分析证实表达的目的蛋白可与结核分枝杆菌H37Rv株感染小鼠的血清发生反应。纯化的rPPE68蛋白免疫新西兰大白兔后,凝集反应与Western-blot证实了抗血清的特异性,双向免疫扩散法测得血清效价为1∶16。结论已成功表达结核分枝杆菌PPE68蛋白,制备了特异性兔抗PPE68多克隆抗体,对结核病的早期诊断提供了一种新的思路。     

11型HPV E7蛋白的表达及其多克隆抗体的制备

目的构建人11型乳头瘤病毒(HPV 11)E7蛋白的原核表达载体,表达纯化后制备抗HPV11E7蛋白的多克隆抗体。方法构建pGEX-4T2-HPV11E7原核表达载体,异丙基-β-D-硫代半乳糖苷(IPTG)诱导大肠杆菌表达可溶性融合蛋白GST-HPV11E7,纯化获取11型HPVE7蛋白。将HPV11E7蛋白免疫新西兰大白兔获得抗HPV11E7的多克隆抗体,用蛋白G琼脂糖纯化获得IgG型多克隆抗体。Western blot法及免疫荧光染色检测该抗体的效价及特异性。结果 SDS-PAGE结果显示,经IPTG诱导6 h后可表达出高水平可溶性GST-HPV11E7融合蛋白。纯化后免疫新西兰大白兔获得抗HPV11E7的血清,纯化获得了IgG型多克隆抗体。Western blot及免疫荧光染色结果显示,兔抗HPV11E7 IgG具有效价高和特异性强的特点。结论成功表达了HPV11E7蛋白并制备了效价较高、特异性较好的IgG型兔抗HPV11E7蛋白多克隆抗体。     

人高迁移率族B1蛋白原核表达、纯化及抗体制备和初步应用

目的:原核表达并纯化人高迁移率族B1蛋白(HMGB1)免疫日本大耳白兔制备其抗体.方法:构建原核表达质粒pRsetA2-HMGB1, 转化大肠杆菌BL21(DE3), HMGB1蛋白经异丙基-β-D-硫代半乳糖苷(IPTG)诱导表达.融合蛋白通过Ni2 -NTA树脂亲和纯化后免疫兔子制备抗体血清.以间接ELISA法检测抗体效价, Western blot和免疫荧光染色鉴定抗体特异性.结果:成功构建原核表达质粒, 表达并纯化HMGB1蛋白.ELISA检测抗体效价为1∶ 16 000以上, Western blot和免疫荧光染色确定抗体具有高度特异性.结论:HMGB1蛋白和抗体的成功制备, 为下一步研究将HMGB1作为肿瘤等疾病治疗的新靶点奠定基础.     

肿瘤睾丸抗原OY-TES-1氨基端截短蛋白及其多克隆抗体的制备

目的获得原核表达的OY-TES-1氨基端截短蛋白(OY-TES-1-N),并制备其多克隆抗体。方法扩增编码OY-TES-1-N 268个氨基酸(A6-R273)的cDNA序列;将PCR产物插入原核表达载体pMAL-C2,构建重组质粒,并转化DH5α菌;通过蓝白斑筛选、DNA测序筛出阳性菌;在优化条件下用IPTG对阳性菌进行诱导表达MBP/OY-TES-1-N融合蛋白;上Amyloseresin亲和层析柱纯化,行Western blot鉴定。以融合蛋白作为抗原免疫新西兰白兔制备抗血清,经活化琼脂糖微球纯化后,采用ELISA法及Western blot法分别检测抗血清的效价和多克隆抗体的特异性。结果成功诱导表达出MBP/OY-TES-1-N融合蛋白。以该蛋白免疫新西兰兔制备抗血清,抗体效价为1∶1 000,Western blot检测证实该抗体能与目的蛋白发生特异性结合。结论成功地表达并纯化了MBP/OY-TES-1-N融合蛋白,并制备了特异性多克隆抗体。     

翻译控制肿瘤蛋白TPT1的原核表达、纯化、抗体制备和初步应用

目的:原核表达并纯化翻译控制蛋白TPT1,免疫日本大耳白兔制备其抗体。方法:构建原核表达质粒pRSE-TA2-TPT1,转化大肠杆菌BL21(DE3),TPT1蛋白经异丙基-β-D-硫代半乳糖苷(IPTG)诱导表达。融合蛋白通过Ni-NTA树脂亲和纯化后免疫兔子制备抗体血清。以间接ELISA法检测抗体效价,Western blot和免疫荧光染色鉴定抗体特异性。结果:在大肠埃希菌中诱导出高水平表达的TPT1融合蛋白,经亲和树脂纯化后免疫大白兔,获得了高特异性的抗TPT1抗血清。结论:成功构建原核表达质粒pRSETA2-TPT1,表达并纯化TPT1蛋白,制备出高滴度、高特异性的多克隆抗体.为进一步研究TPT1在肿瘤等疾病发生、发展过程及治疗中的作用奠定基础。     

HPV16 L1基因的原核表达及免疫反应性鉴定

目的：在大肠杆菌中表达人乳头瘤病毒16型(HPV16)主要衣壳蛋白L1，并鉴定其免疫反应性。方法：将HPV-16L1基因克隆人原核表达载体pThioHisC中，构建重组表达载体。以重组载体分别转化大肠杆菌Top10和DH5α，在IPTG诱导下表达外源基因，用SDS—PAGE和Western blot对表达产物进行鉴定和分析。结果：构建了HPV—16L1基因的原核表达质粒pThioHisC／HPV—16L1，并在大肠杆菌中表达出相对分子质量(Mr)约为70800的蛋白。表达的蛋白能与抗HPV—16L1抗体发生特异性反应。结论：在原核细胞中成功地表达HPV—16L1基因，为HPV—16L1疫苗的研制提供了必要的基础。     

HPV 16 E6E7基因修饰树突状细胞疫苗诱导CTL致CaSki细胞凋亡体外实验研究

目的:采用人乳头状瘤-16(HPV-16)E6E7重组腺病毒(pAd-E6E7)转染树突状细胞(Dendritic cell,DC),观察基因修饰的DC疫苗诱导细胞毒性T淋巴细胞(Cytotoxic Tlymphocyte,CTL)致使CaSki细胞凋亡的效果。方法:将pAd-E6E7转染体外培养的小鼠未成熟树突状细胞制备DC疫苗,激光共聚焦显微镜观察转染的小鼠未成熟树突状细胞绿色荧光蛋白表达,流式细胞术检测转染前后小鼠树突状细胞表面标志物(CD40、CD86、MHCⅡ和CD11C)。DC疫苗诱导产生特异性细胞毒性T淋巴细胞,与CaSki细胞共培养后,采用DAPI、TUNEL及流式细胞术检测CaSki细胞凋亡情况。结果:pAd-E6E7成功转染体外培养的小鼠未成熟树突状细胞,体外转染效率约为40%～50%,成功制备了HPV16 E6E7基因修饰树突状细胞疫苗,诱导产生细胞毒性T淋巴细胞,经DAPI、TUNEL及流式细胞术检测证明CaSki出现凋亡。结论:以带有HPV16 E6E7基因的重组腺病毒载体转染DC制备基因修饰的DC疫苗,诱导CTL致使CaSki细胞出现凋亡。     

特异siRNA抑制宫颈癌细胞中人乳头状瘤病毒16型E6表达的研究

目的 优化HPV-16 E6癌基因特异的U6质粒表达的siRNA，抑制HPV癌基因表达及其对子宫颈癌细胞生长繁殖的影响。方法 选择4个分别针对HPV-16 E6 mRNA外显子和内含子序列为靶序列，合成DNA链，构建表达HPV-16 E6短发卡样dsRNA的重组pSilencer1．0-U6载体，导入HPV-16DNA阳性的宫颈癌细胞株CaSki中，观察该细胞中HPV-16 E6、E7基因表达水平及其蛋白含量的变化，并观察细胞生长被抑制的情况。结果 4种HPV-16 E6 siRNA均能降低宫颈癌细胞CaSki的生长速率。通过细胞生长曲线观察到HPV-16 E6 shRNA表达质粒导入细胞0-96h内，可降低细胞生长速度。荧光定量RT-PCR检测HPV-16 E6 siRNA可使宫颈癌细胞株CaSki中HPV-16 E6、E7基因转录的mRNA水平降低，其中针对E6 mRNA内含子的重组shRNA只抑制E6基因的表达水平。Western blot分析表明，4个HPV-16 E6 siRNA作用72h后，未能检测到宫颈癌细胞中HPV-16 E6蛋白。结论 HPV-16 E6 siRNA能使宫颈癌细胞CaSki生长缓慢；选择针对E6内含子的siRNA作用位点，特异性抑制E6表达；而针对E6外显子的siRNA作用位点，可抑制E6和E7基因的表达，是用于治疗HPV阳性宫颈癌细胞的理想靶位。     

Development and validation of a novel reporter assay for human papillomavirus type 16 late gene expression

To facilitate the investigations of HPV-16 late gene expression HPV-16 reporter plasmids were generated using previously described sub-genomic HPV-16 plasmids, named pBEL and pBELM, that, similar to the full viral genome, produce primarily HPV-16 early mRNAs and very little, if any, late mRNAs in cervical cancer cells. The HPV-16 late L1 gene was replaced by the chloramphenicol acetyltransferase (CAT) reporter gene, or green fluorescent protein (GFP), preceded by the poliovirus internal ribosome entry site (IRES). Results show that the reporter genes mimic the expression of L1 from these plasmids. For example, overexpression of adenovirus E4orf4 protein (E4orf4), polypyrimidine tract binding protein (PTB), arginine/serine-rich SRp30c protein (SRp30c) or alternative splicing factor/splicing factor 2 (ASF/SF2) induced an increased expression of CAT or GFP. Stable cell lines with reporter plasmids pBELCAT and pBELMCAT were also generated. An induction of CAT was observed in HPV-16 reporter cell lines in the presence of the small molecule phorbol 12-myristate 13-acetate (TPA). Further experiments identified the TPA-inducible, hnRNP A2/B1 protein as a regulator of HPV-16 late gene expression. In conclusion, the HPV-16 reporter plasmids and reporter cell lines described herein can be used to identify small molecules and cellular factors that regulate HPV-16 gene expression.     

The human papillomavirus type 11 E1/\E4 protein is not essential for viral genome amplification

An abundant human papillomavirus (HPV) protein E1/\E4 is expressed late in the virus life cycle in the terminally differentiated layers of epithelia. The expression of E1/\E4 usually coincides with the onset of viral DNA amplification. However, the function of E1/\E4 in viral life cycle is not completely understood. To examine the role of E1/\E4 in the virus life cycle, we introduced a single nucleotide change in the HPV-11 genome to result in a truncation of E1/\E4 protein without affecting the E2 amino acid sequence. This mutated HPV-11 genome was introduced into a human foreskin keratinocyte cell line immortalized by the catalytic subunit of human telomerase, deficient in p16(INK4a) expression, and previously shown to support the HPV-11 life cycle when grown in organotypic raft culture. We have demonstrated that E1/\E4 is dispensable for HPV-11 viral DNA amplification in the late stages of the viral life cycle.     

Adenovirus E4orf4 induces HPV-16 late L1 mRNA production

The adenovirus E4orf4 protein regulates the switch from early to late gene expression during the adenoviral replication cycle. Here we report that overexpression of adenovirus E4orf4 induces human papillomavirus type 16 (HPV-16) late gene expression from subgenomic expression plasmids. E4orf4 specifically overcomes the negative effects of two splicing silencers at the two late HPV-16 splice sites SD3632 and SA5639. This results in the production of HPV-16 spliced L1 mRNAs. We show that the interaction of E4orf4 with protein phosphatase 2A (PP2A) is necessary for induction of HPV-16 late gene expression. Also an E4orf4 mutant that fails to bind the cellular splicing factor ASF/SF2 fails to induce L1 mRNA production. Collectively, these results suggest that dephosphorylation of SR proteins by E4orf4 activates HPV-16 late gene expression. Indeed, a mutant ASF/SF2 protein in which the RS-domain had been deleted could itself induce HPV-16 late gene expression, whereas wild type ASF/SF2 could not.     

Codon optimization of the HPV-16 E5 gene enhances protein expression

The human papillomavirus type 16 (HPV-16) E5 protein is an 83-amino-acid, hydrophobic polypeptide that has been localized to intracellular membranes when overexpressed in COS-1 cells. While the HPV-16 E5 protein appears to modulate endosomal pH and signal transduction pathways, genetic analysis of its biological activities has been hampered by low (usually nondetectable) levels of expression in stable cell lines. Sequence analysis of the native HPV-16 E5 gene revealed that infrequent-use codons are used for 33 of its 83 amino acids and, in an effort to optimize E5 expression, we converted these codons to those more common in mammalian genes. The modified gene, 16E5*, generated protein levels that were six- to ninefold higher than those of wild-type HPV-16 E5, whereas the levels of mRNA were unchanged. 16E5* protein was detectable in keratinocytes by immunoblotting, immunoprecipitation, and immunofluorescence techniques and formed disulfide-dependent dimers and higher-order oligomers. Unlike the bovine papillomavirus E5 protein, which is present in the Golgi, 16E5* was localized primarily to the endoplasmic reticulum and its expression reduced the in vitro life span of keratinocytes.     

Oncogenic potential diverge among human papillomavirus type 16 natural variants

We compared E6/E7 protein properties of three different HPV-16 variants: AA, E-P and E-350G. Primary human foreskin keratinocytes (PHFK) were transduced with HPV-16 E6 and E7 and evaluated for proliferation and ability to grow in soft agar. E-P infected keratinocytes presented the lowest efficiency in colony formation. AA and E-350G keratinocytes attained higher capacity for in vitro transformation. We observed similar degradation of TP53 among HPV-16 variants. Furthermore, we accessed the expression profile in early (p5) and late passage (p30) transduced cells of 84 genes commonly involved in carcinogenesis. Most differences could be attributed to HPV-16 E6/E7 expression. In particular, we detected different expression of ITGA2 and CHEK2 in keratinocytes infected with AA and AA/E-350G late passage cells, respectively, and higher expression of MAP2K1 in E-350G transduced keratinocytes. Our results indicate differences among HPV-16 variants that could explain, at least in part, differences in oncogenic potential attributed to these variants.     

Human papillomavirus type 18 E6 and E7 antibodies in human sera: increased anti-E7 prevalence in cervical cancer patients.

Antibody-reactive regions on the human papillomavirus type 18 (HPV-18) E6 and E7 proteins were identified with rabbit polyclonal anti-fusion protein sera by screening of an fd phage expression library containing subgenomic HPV-18 DNA fragments and by testing of overlapping decapeptides representing the E6 and E7 open reading frames. Peptides comprising the delineated regions (designated E6/1 to E6/4 and E7/1) were synthesized and used in an enzyme-linked immunosorbent assay (ELISA) to detect anti-HPV-18 antibodies in human sera. A total of 232 human serum samples (identical numbers of cervical cancer patients and age-matched controls) collected in Tanzania were tested. Similar prevalences (between 0.8 and 4.3%) of antibodies recognizing the different E6 peptides were found in the sera from tumor patients and controls. With a synthetic 28-mer peptide (designated pepE701) comprising the E7/1 region, a significant difference was found: 10 of 116 tumor serum samples but 0 of 116 control serum samples showed a specific reaction (P less than 0.001). This observation confirms earlier results with HPV-16 E7 fusion proteins (I. Jochmus-Kudielka, A. Schneider, R. Braun, R. Kimmig, U. Koldovsky, K. E. Schneweis, K. Seedorf, and L. Gissmann, J. Natl. Cancer Inst. 81:1698-1704, 1989). A lower prevalence of anti-HPV-18 E7 antibodies was observed when 188 human serum samples collected in Germany from tumor patients and controls were tested (3 of 94 positive in the cancer group; 0 of 94 positive in the control group). The type specificity of anti-HPV-18 E7 antibodies was demonstrated when the HPV type found by Southern hybridization in the cervical cancer biopsies was compared with seroreactivity: 4 of 8 serum samples obtained from HPV-18 DNA-positive but 0 of 16 serum samples from HPV-18 DNA-negative tumor patients reacted in the HPV-18 E7 ELISA. In addition, HPV-18-positive sera failed to react in a peptide ELISA with the homologous HPV-16 E7 region (M. Müller, H. Gausepohl, G. de Martinoff, R. Frank, R. Brasseur, and L. Gissmann, J. Gen. Virol. 71:2709-2717, 1990) and vice versa.