小鼠抗人细胞色素P450 1A2合成肽抗血清的制备与鉴定

目的：制备小鼠抗人细胞色素P450 1A2（CYP1A2）抗体及其特性鉴定。方法：利用生物信息学方法分析CYP1A2蛋白的序列,根据4个指标（亲水性、柔韧性、抗原性及表面性）选择欲合成的多肽序列,设计、合成CYP1A2多肽。将其与载体蛋白钥孔戚血蓝素（keyhole limpet hemocyanin,KLH）偶联,免疫BALB/c雌性小鼠制备抗CYP1A2抗体。用间接ELISA法测定抗体的效价,Western blot鉴定其特异性。结果：成功地获得针对小分子CYP1A2的抗体。该抗体效价为1∶16000,可与CYP1A2合成肽及天然CYP1A2出现特异性反应。Western blot的结果显示,该抗体识别的相应抗原的相对分子质量（Mr）为58000。结论：合成的多肽-KLH复合物具有免疫原性,可用于制备相应的抗体。制备的小鼠抗CYP1A2合成肽抗体的效价高及特异性良好。     

人类肥胖相关新基因LYRM1多克隆抗体的制备及鉴定

目的:制备兔抗人LYRM1蛋白的多克隆抗体并对其进行初步鉴定。方法:预测LYRM1蛋白的抗原表位,设计并合成出一段由17个氨基酸组成的多肽,将合成肽与载体蛋白钥孔戚血蓝素(KLH)偶联作为抗原,免疫新西兰大白兔,制备抗LYRM1蛋白的多克隆抗体,利用ELISA、Westernblot鉴定其效价及特异性,并将该抗体用于人脂肪组织LYRM1的表达检测。结果:制备了兔抗人LYRM1蛋白的多克隆抗体并证实此抗体效价较高、特异性较强。结论:采用人工合成多肽作为半抗原成功制备了人类肥胖相关新基因LYRM1的多克隆抗体。     

肠出血型大肠埃希菌O157：H7 EspF蛋白多克隆抗体的制备和初步纯化

目的制备肠出血型大肠埃希菌（EHEC）O157：H7EspF蛋白多克隆抗体并初步纯化。方法生物信息学方法分析EHECO157：H7EspF蛋白的柔韧性、亲水性、表面可能性及抗原表位,选取1条由15个氨基酸残基组成的多肽为半抗原,在其C端偶联钥孔血蓝蛋白（KLH）,免疫新西兰大白兔制备抗血清。ELISA测定抗血清效价,免疫印迹法鉴定其特异性,辛酸-硫酸铵法初步纯化抗血清,SDS-PAGE检测抗体纯度。结果选择EspF蛋白抗原指数最高的肽段72-TPSRPAPPPPTSGQA-86（0.506）为半抗原,合成抗原多肽经高效液相色谱鉴定,纯度为95.78%,经质谱分析其分子量为1563.76Mr,与目的多肽分子量一致;加强免疫3次后,EHECO157：H7EspF蛋白的抗血清效价达1：2048000;该血清对EHECO157：H7野生株和espF突变株（△espF）的EspF蛋白均有特异性,并经辛酸-硫酸铵法获得一定纯度的抗体。结论成功地制备了效价高、特异性强的EHECO157：H7EspF蛋白多克隆抗体。     

尤文肉瘤EWS-FLI1融合蛋白B淋巴细胞表位的预测及鉴定

目的:预测及鉴定尤文肉瘤EWS-FLI1融合蛋白的B淋巴细胞表位。方法:采用综合法预测EWS-FLI1蛋白的二级结构及B淋巴细胞表位,运用标准Fmoc方案合成预测的表位肽,HPLC和MS进行表位肽的纯度分析及分子量鉴定,ELISA法检测表位肽的抗原性,并测定表位肽特异性免疫血清效价,Western blot鉴定免疫血清与EWS-FLI1蛋白亲合力。结果:通过综合法预测得到3个高分值的B淋巴细胞表位,HPLC分析合成的表位肽纯度>85%,MS鉴定表位肽的分子量无误,ELISA法检测证实3个B淋巴细胞表位肽均可获得强的抗原抗体反应,其中表位肽P2的抗原性最强,在1∶40时A450=2.46,达到最高,1∶10 240稀释后抗原抗体反应仍呈阳性;用这3个B淋巴细胞表位肽免疫新西兰兔也能获得理想的抗体效价,其中表位肽P2获得的抗体效价最高,1∶512 000稀释时A450=1.11;Western blot鉴定表位肽P1、P2免疫血清能够结合EWS-FLI1蛋白。结论:尤文肉瘤EWS-FLI1蛋白的B淋巴细胞表位肽P1、P2具有潜在的抗原性和免疫原性。     

人rBPI23在大肠杆菌DH5α中的表达及其多克隆抗体的制备

目的制备人rBPI23蛋白并免疫家兔获得特异性多克隆抗体。方法将本室制备的pBV220-synBPI600表达载体转化感受态E.coliDH5α,温控诱导后,获得以包涵体形式表达的目的重组蛋白;用SDS-PAGE鉴定分子质量,West-ernblot鉴定抗原性;免疫家兔获得抗rBPI23抗血清,经饱和硫酸铵沉淀获得多克隆抗体,间接法ELISA检测抗体效价,Westernblot分析抗体的特异性。结果重组蛋白主要以包涵体形式表达,SDS-PAGE显示其分子质量约23ku,与预期结果相符;重组蛋白能与市售兔抗人BPI抗体特异性结合;免疫家兔获得高效价(1∶320000)抗血清,上述抗体能与rBPI23及人BPI标准品特异性结合。结论成功制备了人rBPI23,免疫家兔获得高效价抗人rBPI23多克隆抗体,为制备单克隆抗体及后期建立BPI免疫学检测方法奠定基础。     

兔抗人细胞色素P450 1A2多克隆抗体的制备及鉴定

目的：制备兔抗人细胞色素P4501A2（CYP1A2）抗体及其特性鉴定。方法：利用生物信息学方法分析CYP1A2蛋白的序列，根据亲水性、抗原性、柔韧性及表面性等指标选择多肽序列，合成CYP1A2多肽，与载体蛋白钥孔戚血蓝素（Keyhole limpet hemocyanin，KLH）偶联，免疫日本大耳白兔制备抗CYP1A2抗体。辛酸-硫酸铵法纯化抗体，间接ELISA法测定抗体的效价及相对亲和力常数，Western blot鉴定其特异性，免疫组化进行定位。结果：获得针对小分子CYP1A2的抗体。该抗体效价为1∶16000；相对亲和力常数在10^5-10^6/M，具有实用价值；可与CYP1A2合成肽及天然CYP1A2出现特异性反应；可识别正常人肝脏组织CYP1A2；Western blot的结果显示，该抗体识别的相应抗原的相对分子质量为58000。结论：合成的多肽-KLH复合物具有免疫原性，可用于制备相应的抗体。制备的兔抗CYP1A2合成肽抗体可应用于酶联免疫吸附试验、免疫印迹、免疫组化实验。     

兔抗人细胞色素P450 4A11合成肽抗体的制备与鉴定

目的：制备兔抗人细胞色素P450 4A11（CYP4A11）抗体，并对其特性进行初步鉴定。方法：利用生物信息学方法分析CYP4A11蛋白的序列，根据亲水性结构、柔韧区、抗原指数及表面概率结构等指标选择多肽序列、合成CYP4A11多肽，与载体蛋白钥孔戚血蓝素（KLH）偶联，免疫大耳白兔制备抗CYP4A11抗体。辛酸一硫酸铵法纯化抗体，对纯化的抗体进行ELISA、Western blot、免疫组化等鉴定。结果：获得抗CYP4A11合成肽的抗体。该抗体效价为1：32000。可与CYP4A11合成肽及天然CYP4A11出现特异性反应，该抗体识别的相应抗原的相对分子质量（Mr）为53000，可识别正常肝脏的CYP4A11。结论：合成的多肽-KLH复合物具有免疫原性，可用于制备相应的抗体。制备的兔抗CYP4A11合成肽抗体可应用于ELISA、Westernblot、免疫组化等实验。     

OLFM1蛋白的生物信息学分析及其多克隆抗体制备与鉴定

目的:利用生物信息学分析OLFM1蛋白,并制备其多克隆抗体。方法:根据生物信息学分析预测OLFM1蛋白的二级结构、亲水性、抗原性等理化特性,以这些分析预测为依据,经过同源性检索后设计出一段由20个氨基酸组成的多肽,免疫家兔,获得的多克隆抗体经Western blot和ELISA方法鉴定其特异性和效价。结果:制备的兔抗人OLFM1多克隆抗体效价为1∶32000,蛋白质印迹证实该抗体具有较好的反应性和特异性。结论:利用生物信息学软件成功地预测出OLFM1蛋白的抗原性,并制备了效价较高的特异性抗人OLFM1多克隆抗体。     

细胞色素P450 3A4抗原表位的分析及其抗体的制备与鉴定

目的：制备兔抗人细胞色素P450 3A4（CYP3A4）抗体及其特性鉴定。方法：利用生物信息学方法分析CYP3A4蛋白的序列,根据亲水性、抗原性、柔韧性及表面性等指标选择多肽序列,合成CYP3A4多肽,与载体蛋白钥孔戚血蓝素（KLH）偶联,免疫日本大耳白兔制备抗CYP3A4抗体。辛酸-硫酸铵法纯化抗体,间接ELISA测定抗体的效价及相对亲和力常数,Western blot鉴定其特异性,免疫组化进行定位。结果：获得针对小分子CYP3A4的抗体。该抗体效价为1∶16000;相对亲和力常数在10^5～10^6M^-1,具有实用价值;可与CYP3A4合成肽及天然CYP3A4出现特异性反应;可识别正常人肝脏组织CYP3A4;Western blot的结果显示,该抗体识别的相应抗原的相对分子质量（Mr）为46000。结论：合成的多肽-KLH复合物具有免疫原性,可用于制备相应的抗体。制备的兔抗CYP3A4合成肽抗体可应用于ELISA、Western blot和免疫组化实验。     

Trim22 B细胞表位预测及多克隆抗体制备与鉴定

目的:预测人Trim22的B细胞抗原表位,制备并鉴定其多克隆抗体。方法:利用生物信息学软件分析Trim22的氨基酸序列,确定抗原表位并人工合成多肽。将合成肽与牛血清白蛋白(BSA)偶联,免疫大白兔制备抗Trim22的抗体。经饱和硫酸铵沉淀法纯化抗体,并对抗体进行ELISA、Western blot鉴定。结果:获得抗Trim22的多克隆抗体,抗体效价为1∶16 000,该抗体能特异性地识别包含(382～397)区段的Trim22缺失突变体,同时该抗体不能识别Trim22旁系同源分子Trim5α、Trim6和Trim34α。结论:采用人工合成多肽作为半抗原制备出抗Trim22的多克隆抗体,对研究内源性Trim22与HIV-1衣壳蛋白的相互作用机制具有重要价值。     

腺病毒六邻体蛋白型间线性化抗原位点的研究

目的 对人类腺病毒（adenovirus,AdV)六邻体型间抗原位点的特性进行研究。方法 通过计算机对腺病毒六邻体氨基酸序列进行比较分析，结合抗原性的预测结果和六邻体蛋白三维空间结构的肽段暴露状态，选定了保守性抗原位点进行多肽合成或通过构建重组质粒表达蛋白，将合成的六邻体肽段和表达纯化的蛋白抗原免疫动物后，用免疫印迹和间接免疫荧光方法检测抗血清的免疫特异性，结果 免疫印迹分析显示，抗多肽抗体和抗重组蛋白抗体均与腺病毒的六邻体蛋白特异性识别，间接免疫荧光显示，腺病毒感染HeLa细胞核内荧光着色，并且抗血清有较好的腺病毒型间反应性，合成多肽抗体与含有相同肽段的重组蛋白抗原产生特异性结合。结论 在腺病毒六邻体蛋白中存在有线性化的型间抗原位点，全盛的六邻体多肽和表达重组蛋白可用于诊断价值抗体的研制。     

Immunogenicity of overlapping synthetic peptides covering the entire sequence of Haemophilus influenzae type b outer membrane protein P2.

Haemophilus influenzae type b is a major cause of bacterial meningitis in young children. Antibodies against the outer membrane protein P2 are protective in the infant rat model of bacteremia. To identify conserved, surface-exposed, and protective epitopes of P2, 17 overlapping peptides covering the entire sequence of the protein were synthesized. Antisera from mice, guinea pigs, and rabbits raised against chromatographically purified P2 were tested for their reactivities to the peptides by enzyme-linked immunosorbent assays (ELISA). Three major linear immunodominant B-cell epitopes were mapped to residues 53 to 81, 241 to 265, and 314 to 341 of mature P2. Human convalescent-phase antisera also reacted strongly with these three epitopes. Rabbit antisera against all peptide-keyhole limpet hemocyanin conjugates except two peptides containing residues 8 to 19 and 302 to 319 recognized the corresponding peptides in ELISA and reacted with P2 on immunoblots. Immunization with all unconjugated peptides, except the 19 N-terminal residues, induced very strong peptide-specific antibody responses, and these antisera reacted with P2 on immunoblots. Rabbit antisera raised against peptides corresponding to residues 1 to 14, 125 to 150, 193 to 219, and 241 to 319 also recognized P2 purified from H. influenzae nontypeable isolates. Identification of these immunodominant B-cell epitopes and conserved regions is a first step toward the rational design of a universal H. influenzae vaccine.     

G145R突变后HBsAg"a"决定簇合成肽的免疫学特性分析

目的研究G145R突变后乙肝表面抗原(HBsAg)"a"决定簇合成肽的免疫学特性改变情况. 方法首先合成2条短肽P1-wt和P2-145R,分别代表野毒株和G145R突变后HBsAg"a"决定簇合成肽.然后用β-巯基乙醇(2-ME)变性试验以及用乙肝疫苗标准品制备的小鼠多抗血清研究2条合成肽的空间构象以及抗原性异同.最后用等量合成肽免疫小鼠,用酶免疫法、竞争抑制试验和Western blot试验等研究G145R突变后"a"决定簇合成肽的免疫原性改变.结果合成肽P1-wt和P2-145R用2-ME温和变性后,PAGE结果表现为相对分子质量(Mr)为4×103左右的单一条带,而变性前2条合成肽均表现为Mr是从4×103到30×103的弥漫条带,主带位置在5×103和10×103,分别相当于二聚体和四聚体位置;用HBsAg的多克隆抗体(anti-HBs)检测合成肽的抗原性,结果在固定抗原量的前提下,在抗体1∶32 000稀释时仍可检测到P1-wt的阳性结果,而当同一抗体稀释到1∶8000时,P2-145R检测结果即为阴性.合成肽P2-145R免疫小鼠产生的抗体与P1-wt合成肽的反应滴度比与P2-145R合成肽本身的反应低4～8倍. 结论针对HBsAg"a"决定簇合成肽可自发形成一定的空间构象,G145R突变株的HBsAg"a"决定簇的抗原性和免疫原性与野毒株相比发生了明显改变,为正确评价G145R变异株的流行危害以及现行疫苗的保护效果提供了实验依据.     

Elucidation of linear epitopes of pertussis toxin using overlapping synthetic decapeptides: identification of a human B-cell determinant in the S1 subunit indicative of acute infections

To identify relevant linear epitopes within the immunodominant ADP-ribosyl transferase (S1 subunit) of pertussis toxin (PT), its complete amino acid sequence was synthesized as consecutive, overlapping decapeptides on solid phase and probed for seroreactivity with pertussis specific human antisera in 'peptide scans'. Comparison of the resulting antigenic profiles revealed two distinct types of human antisera, though amino acids 140-200 could not be assessed as the corresponding peptides reacted non-specifically with the detection system. Human anti-pertussis sera predominantly recognized linear immunodominant epitopes located in three separated segments spanning amino acids 3-16, 21-30, and 211-222. Antisera originating from infants with acute B. pertussis infections (type I) identified determinants in all three segments, while type-II antisera from convalescent patients only recognized epitopes in the N-terminal regions. The binding of pertussis specific antisera—both type I and type II—to the holotoxin was inhibited by preincubation of antibodies with synthetic peptides corresponding to two linear determinants located at the N-terminus of S1: R 3-16 and R 21-30. However, competitive binding of antibodies to PT and to synthetic peptides equivalent to the third epitope (R 211-222) was only observed with type I antisera. Thus, the linear immunogenic determinant identified at the C-terminus of the A-protomer represents a human epitope which is apparently specific for antisera from pertussis patients with acute infections. The possible application of this determinant in serologic diagnosis will be a valuable tool to detect and distinguish acute Bordetella pertussis infections.     

猪瘟病毒E2糖蛋白抗原表位的预测、多肽合成及特性研究

目的：研究CSFV E2蛋白免疫原性肽的生物学特性。方法：应用计算机分析软件对猪瘟病毒＆糖蛋白的抗原表位进行了预测，结合＆基因的变异分析，人工合成了两条多肽(Pep1和Pep2)序列，与抗mE2蛋白的兔血清和抗mE2的8株单抗进行反应，并将两条多肽分别与载体蛋白(BSA)进行偶联和免疫家兔。结果：两条多肽均与兔的抗血清及单抗A11反应；多肽Pep2与单抗D5和D8反应。多肽Pep1与BSA载体蛋白偶联(Pep1-BSA)，免疫家兔后能够产生针对多肽Pep1的抗体。结论：两条多肽Bep1和Pep2中，只有多肽Pep1具有很好的反应原性和免疫原性。     

Mapping of linear B-cell epitopes of the S2 subunit of pertussis toxin.

The linear immunogenic and antigenic structure of the S2 subunit of pertussis toxin was investigated with synthetic peptides corresponding to regions of the protein sequence predicted to contain surface-exposed hydrophilic beta turns. Five peptides as peptide-bovine serum albumin conjugates were recognized by anti-pertussis toxin antiserum and were thus designated "immunogenic epitopes." Two prominent immunogenic epitopes were specified by peptides corresponding to sequences spanning R107-120 and R186-199, whereas peptides corresponding to residues R35-50 and R91-106 were only bound in low titer. Three peptides as thyroglobulin conjugates elicited antisera in rabbits that bound intact pertussis toxin by enzyme-linked immunosorbent assay and immunoblot. These peptides were designated "antigenic epitopes." The most prominent antigenic determinant was localized to the N-terminal end of the S2 sequence encompassing residue R1-7. Peptides R35-50 and R91-106 represented two minor antigenic epitopes. Antisera to two additional peptides corresponding to residues R134-149 and R186-199 recognized the S2 subunit only by Western blotting (immunoblotting). Only antiserum raised against peptide R91-106 also recognized the S3 subunit by Western blotting, indicating a marked antigenic and probably also structural difference between the two highly homologous subunits.     

Identification of immunodominant epitopes on the membrane protein of the severe acute respiratory syndrome-associated coronavirus

Similar to other coronaviruses, the membrane (M) protein of severe acute respiratory syndrome-associated coronavirus (SARS-CoV) is a major transmembrane glycoprotein with multiple biological functions. To date, limited information is available about its antigenic properties. In this study, we identified two major immunodominant epitopes on the M protein located in the extreme N-terminal region (residues 1 to 31) and the interior C-terminal region (residues 132 to 161), respectively, by Pepscan analyses against convalescent-phase sera from SARS patients and antisera from virus-immunized mice and rabbits. Synthetic peptides M1-31 derived from the N-terminal epitope and M132-161 derived from the C-terminal epitope were highly reactive with all of the convalescent-phase sera from 40 SARS patients but not with 30 control serum samples from healthy blood donors, suggesting their potential application for serologic diagnosis of SARS. We showed that both peptides (M1-31 and M132-161) were able to induce high titers of antibody responses in the immunized rabbits, highlighting their antigenicity and immunogenicity. These findings provide important information for developing SARS diagnostics and vaccines.     

Immunogenicity of synthetic peptides of Haemophilus influenzae type b outer membrane protein P1.

To identify the B- and T-cell epitopes of P1 of Haemophilus influenzae type b, 13 peptides covering 90% of the protein were chemically synthesized. Mouse, guinea pig, and rabbit antisera raised against purified native P1 were tested for their reactivities against the peptides in peptide-specific enzyme-linked immunosorbent assays (ELISAs). Six immunodominant linear B-cell epitopes were mapped to residues 103 to 137, 189 to 218, 248 to 283, 307 to 331, 384 to 412, and 400 to 437 of the mature P1 protein. When P1 peptides were screened for their reactivities with three human convalescent-phase serum specimens, peptides corresponding to residues 39 to 64, 226 to 253, and 400 to 437 reacted strongly with the antisera. Four regions (residues 39 to 64, 226 to 253, 339 to 370, and 400 to 437) contained murine T-cell epitopes. Rabbit antipeptide antisera were tested for their reactivities with the immunizing peptides and P1 protein by ELISA and immunoblots. All anti-P1 peptide antisera except those raised against peptide HIBP1-8 (residues 279 to 312) or HIBP1-8-keyhole limpet hemocyanin conjugate were shown to be specific for their respective immunizing peptides by ELISA. In addition, rabbit antisera raised against the synthetic peptides corresponding to residues 1 to 29, 39 to 64, 103 to 137, 189 to 218, 226 to 253, 248 to 283, 307 to 331, and 400 to 437 of the mature P1 protein recognized the P1 protein from both typeable and nontypeable isolates. These results suggest that these peptides contain epitopes highly conserved among typeable and nontypeable strains of H. influenzae. However, none of the antipeptide antisera have bactericidal activity, nor were they protective against H. influenzae type b in the infant rat model of bacteremia.     

Prokaryotic expression and identification of B- and T-cell combined epitopes of Em95 antigen of Echinococcus multilocularis

Objective: This study is to clone and identify B- and T-cell combined epitopes from Em95 antigen. Methods: The B- and T-cell combined epitopes were predicted using bioinformatic software. Two DNA sequences of Em95-1 (which contained the coding region of one B- and T-cell combined epitope) and Em95-2 (which contained the coding regions of two B- and T-cell combined epitopes) were amplified by PCR. Em95-1 and Em95-2 were cloned into pET32a vector for protein expression. Rabbit was immunized with the expressed proteins of rEm95-1 and rEm95-2 to produce polyclonal antibodies. The immunogenicity and antigenicity of rEm95-1 and rEm95-2 were examined by Western blot analysis. Results: The three B- and T-cell combined epitopes were successfully cloned and expressed in PET32a vector. The recombinant antigens of rEm95-1 and rEm95-2 could specifically bind the human serum from patients with alveolar echinococcosis and specifically bind the prepared polyclonal antibodies. Conclusion: Three B- and T-cell combined epitopes were successfully cloned with good immunogenicity and antigenicity. Our data suggest that B- and T-cell combined epitopes predicted from the Em95 antigen may be used for the construction of high-valence vaccines and as targets for prevention of echinococcosis.     

β-Netrin抗原表位的分析及其抗体的制备与鉴定

目的:制备抗神经细胞突起生长诱向因子(β-Netrin)的多克隆抗体(pAb)和单克隆抗体(mAb),并对其特异性进行鉴定。方法:应用GoldKey软件分析人βNetrinC末端结构域氨基酸的序列(共114个氨基酸),确定抗原表位并人工合成多肽。然后采用碳化二亚胺法,将合成肽与载体蛋白牛血清白蛋白(BSA)偶联作为抗原,免疫BALB/c小鼠。取免疫小鼠脾细胞与Sp2/0骨髓瘤细胞常规融合,依次进行HAT选择培养,间接ELISA法筛选阳性的杂交瘤细胞并克隆化。对分泌的mAb的效价、Ig亚类(型)及特异性,分别用间接ELISA和Westernblot进行鉴定。同时,通过免疫细胞化学染色鉴定抗体的特异性。另外,以偶联的分子免疫新西兰白兔,制备抗β-Netrin的pAb,用Westernblot鉴定其特异性。结果:以确定的此16个氨基酸的序列NH2-FRGKRT-LYPESWTDRG-COOH作为抗原表位,以人工合成多肽与BSA偶联作为免疫原,获得3株可稳定分泌特异性抗β-Netrin mAb的杂交瘤细胞。免疫细胞化学染色结果表明,这3株抗体均能特异性地识别细胞中的抗原。另外,制备了高效价的抗β-Netrin的pAb,并能特异性地识别原核表达的β-Netrin蛋白。结论:采用人工合成多肽作为半抗原成功地制备出抗β-Netrin的pAb和mAb。