志贺氏I型痢疾杆菌O-特异性多糖与破伤风类毒素结合疫苗的制备及其在小鼠体内的免疫原性

从志贺氏I型痢疾杆菌LPS中分离纯化出O SP半抗原 ,以ADH为连接剂将其与TT结合形成O SP TT结合疫苗 ,并用此结合疫苗免疫NIH小鼠 ,结果显示单独使用O SP免疫后 ,小鼠血清中没有抗LPS抗体产生 ,而用O SP TT免疫后小鼠血清中产生了抗LPSIgG和IgM抗体 ,且IgG抗体水平高于IgM抗体 ;O SP TT免疫组第二次和第三次免疫后IgG抗体水平均有显著的升高 (P <0 0 1) ,但第二次和第三次免疫后血清IgM抗体虽有升高 ,但与前一次免疫相比均无显著差异 (P >0 0 5 ) ,表明O SP TT结合疫苗具有加强免疫应答效应。补体介导的体外杀菌活性试验结果证明 ,O SP TT免疫血清在 1∶16 0倍稀释后仍对志贺氏I型痢疾杆菌具有特异性杀菌活性。     

C群脑膜炎球菌多糖-rP64K结合物的制备及免疫原性

用1-氰基-4-二甲基氨基吡啶·四氟化硼(CDAP)活化C群脑膜炎球菌多糖(GCMP),以己二酰肼(ADH)作为连接子,与重组B群脑膜炎球菌外膜蛋白64 KD(rP64K)在碳二亚胺的(EDAC)作用下结合,制备GCMP-P64K结合物。纯化后免疫NIH小鼠,用间接ELISA法检测小鼠血清中抗GCMPIgG抗体水平,并GCMP-TT结合物比较载体诱导的免疫抑制。所制备多糖-蛋白结合物(GCMP-P64K)保持了GCMP抗原特异活性,结合物免疫小鼠后可诱生比多糖单独免疫更高水平的GCMP血清IgG抗体,并能形成免疫记忆,为研究理想载体蛋白提供了新的思路。     

不同蛋白载体的痢疾多糖结合疫苗小鼠免疫原性对比试验

试验中以小鼠为动物模型,对不同蛋白载体的痢疾多糖结合疫苗进行免疫效果观察。3种福氏2a痢疾结合疫苗和3种宋内氏痢疾结合疫苗分别皮下免疫NIH小鼠,同时设置O-SP(O-特异性多糖)对照组,免疫3针,在不同免疫针次间采血,用ELISA测定抗体滴度。单独使用福氏2aO-SP和宋内氏O-SP免疫后,小鼠血清中几乎没有抗LPS IgG抗体产生,而用结合疫苗免疫后,小鼠血清中产生了抗LPS IgG抗体,且第二次、第三次免疫后,小鼠血清中抗LPS IgG抗体水平有显著升高,表明结合疫苗具有加强免疫应答效应。三种不同的痢疾结合疫苗相比较,F2a-O-SP-rEPA结合疫苗较F2a-O-SP-TT结合疫苗和F2a-0-SP—DT结合疫苗的小鼠抗LPS IgG抗体水平高,S-O-SP-rEPA结合疫苗较S-O-SP-TT结合疫苗和S-O-SP—CRM9,结合疫苗的小鼠抗LPS IgG抗体水平高。以rEPA作为载体的痢疾结合疫苗比DT,TT作为载体的痢疾结合疫苗的免疫原性要强。     

甲型副伤寒菌O-特异性多糖与破伤风类毒素结合菌苗的制备及其在小鼠体内的免疫原性

以脱毒后去除类脂A的甲型副伤寒杆菌高分子量O SP1和低分子量O SP2 为特异性抗原 ,以破伤风类毒素 (TT)为蛋白质载体 ,用己二酸二肼 (ADH)作为连接剂制备的两种结合物及其多糖免疫NIH小鼠 ,结果显示单独注射O SP1或O SP2 免疫小鼠后 ,均不能刺激小鼠产生抗 LPS抗体 ;而用O SP1 TT和O SP2 TT结合物免疫后 ,小鼠血清中均产生了特异性抗 LPSIgG和IgM抗体 ,且O SP1 TT免疫组血清中IgG抗体水平明显高于O SP2 TT免疫组 ,两组结合物免疫血清中抗体类型以IgG为主。O SP1 TT结合物免疫组第二次免疫和第三次免疫后IgG抗体水平均较前一次有显著升高 (p<0 0 1)说明 ,O SP1 TT结合物具有加强应答效果。补体介导的体外杀菌试验证明 ,O SP1 TT与O SP2 TT结合物免疫血清具有特异性杀菌活性。     

A群奈瑟氏脑膜炎球菌荚膜多糖-破伤风类毒素结合疫苗的制备及其免疫原性研究

采用溴化氰(CNBr)活化多糖,以无水己二酸二肼(ADH)作为连接剂,1乙基13(3二甲基氨基丙基)碳化二亚胺(EDAC)为偶联剂制备A群奈瑟氏脑膜炎球菌荚膜多糖(GAMP)与破伤风类毒素(TT)的结合物,经皮下免疫NIH小鼠,用ELISA检测小鼠血清中抗GAMP及抗载体蛋白的IgG抗体水平。用补体介导的体外杀菌试验检测血清中GAMP抗体的杀菌活性。结果显示,实验中制备的多糖衍生物和多糖蛋白质结合物都具有GAMP抗原特异活性。结合物免疫小鼠后可诱生比多糖单独免疫更高水平的GAMP血清IgG抗体,并能形成免疫记忆,产生再次应答。结合物免疫小鼠所诱生的血清GAMP抗体较之多糖组具有更强的体外杀菌活性。表明此方法制备的结合物可获得优于多糖的、稳定的特异免疫原性。     

伤寒Vi多糖结合疫苗免疫小鼠后的抗体类型及动态分析

伤寒Vi多糖结合疫苗和Vi多糖疫苗分别免疫小鼠,分离血清,采用间接ELISA法测定不同时点血清中特异性IgA、IgM、IgG及其亚类(IgG1、IgG2a、IgG3)的抗体滴度。结果显示,免疫一针后,Vi多糖结合疫苗组的IgG抗体GMT值明显升高,第二针有加强效应(P<0.01);所测3种IgG亚型中IgG2a抗体滴度升高明显;Vi多糖和结合疫苗免疫小鼠后,血清中IgA和IgM抗体滴度均有显著升高,但无加强应答。显示Vi多糖结合疫苗在诱导小鼠血清IgG应答方面有加强效应。     

阳离子脂质体DOTAP佐剂对H5N1流感病毒裂解疫苗免疫效果的影响

目的研究阳离子脂质体DOTAP佐剂对H5N1型流感病毒裂解疫苗免疫效果的影响。方法制备DOTAP阳离子脂质体流感病毒裂解疫苗(简称DOTAP流感裂解疫苗),检测其包封率。将BALB/c小鼠分为13组,分别用含0.1、1.0、10.0μg HA/只剂量以DOTAP、Al(OH)3、CPG-ODN为佐剂以及不含佐剂的流感裂解疫苗于0、21天皮下免疫,PBS作为对照组,用血凝抑制试验检测小鼠初次免疫后21、42天血清HI抗体滴度;用ELISA检测初次免疫后21、42天血清特异性IgG抗体、IgG1、IgG2a亚类抗体滴度,以及初次免疫后42天小鼠脾脏单个核细胞体外经抗原刺激后细胞因子IL-2、IL-4、IFN-γ的分泌水平。将BALB/c小鼠分为3组,分别用含不同DOTAP剂量(100、300、600μg/只)的DOTAP流感裂解疫苗于0、21天皮下免疫,检测初次免疫后21、42天小鼠血清HI抗体滴度和IgG抗体滴度。结果 DOTAP流感裂解疫苗粒径在300~400 nm,带正电荷,包封率在50%以上;DOTAP流感裂解疫苗诱导的HI抗体水平和特异性IgG抗体水平均高于流感裂解疫苗,而与铝佐剂和Cp G-ODN佐剂间差异无统计学意义;DOTAP流感裂解疫苗产生的抗体仍以IgG1亚类抗体为主,免疫后42天诱导的IgG2a亚类抗体水平高于流感裂解疫苗和铝佐剂,低于Cp G-ODN佐剂;DOTAP流感裂解疫苗免疫后既分泌高水平Th1型细胞因子IFN-γ,同时也分泌高水平Th2型细胞因子IL-4;不同DOTAP剂量的DOTAP流感裂解疫苗免疫后,其HI抗体滴度和IgG抗体滴度在低、中、高剂量组之间存在明显的量效关系。结论 DOTAP作为H5N1型流感病毒裂解疫苗的佐剂可显著提高流感裂解疫苗的免疫原性,其对体液免疫应答的增强作用不低于铝佐剂和Cp G-ODN佐剂,并具有诱导细胞免疫应答的能力。     

轮状病毒灭活疫苗和减毒活疫苗序贯免疫的体液免疫应答效果

目的:评价采用轮状病毒灭活疫苗进行初始免疫,减毒活疫苗进行加强免疫的序贯免疫方案的体液免疫应答效果。方法:将实验小鼠随机分为4组(口服疫苗组、序贯疫苗组、口服对照组及序贯对照组),按相应方案免疫后,ELISA检测血清轮状病毒特异性IgG和IgA、肠道轮状病毒特异性IgA;微量中和实验检测血清病毒特异性中和抗体;同时采用ELISA分析口服活疫苗后病毒排出情况。结果:与对照组相比,序贯疫苗组小鼠产生的轮状病毒特异性血清IgG、IgA、中和抗体及肠道IgA水平显著升高。与口服疫苗组相比,序贯疫苗组的免疫方案诱发的轮状病毒特异性血清IgG、IgA、中和抗体水平显著升高,肠道IgA水平两组间没有显著差异。同时,与口服疫苗组相比,序贯疫苗组中轮状病毒灭活疫苗进行的初始免疫未影响第一次口服活疫苗后病毒的排出量和排出时间,但序贯疫苗组第二次口服活疫苗后病毒的排出量迅速减少,排毒时间快速缩短,与口服疫苗组第三次服苗后病毒的排出量和排出时间相似。结论: 轮状病毒灭活疫苗和减毒活疫苗序贯免疫可有效诱发小鼠全身和黏膜局部的体液免疫应答,该方案将有可能成为轮状病毒疫苗临床应用的候选方案。     

枸杞多糖对甲型H1N1流感裂解疫苗黏膜接种的免疫增强作用

探讨枸杞多糖(Lycium barbarum polysaccharide,LBP)对不同剂量甲型H1N1流感裂解疫苗黏膜免疫的佐剂效力。设单独免疫LBP组和不免疫组作为对照,BALB/c小鼠以滴鼻方式免疫两次,间隔三周,二次免疫后两周收集小鼠血清、鼻洗液和脾脏淋巴细胞。结果显示血清中甲流特异性IgG和HI抗体滴度与接种疫苗剂量呈正相关,LBP的添加可提高体内抗体水平。高剂量组小鼠鼻洗液中也检测到特殊异性sIgA。单独疫苗组和添加佐剂组均能在体内诱导产生IgG1和IgG2a,所有组别IgG1抗体水平均略高于IgG2a,表明滴鼻接种裂解疫苗诱导Th1/Th2混合型免疫,LBP对Th1和Th2型免疫反应均有增强作用。高剂量疫苗添加LBP佐剂组小鼠脾脏细胞分泌IFN-γ水平显著高于其他组别,表明其在小鼠体内诱导了较强烈的细胞免疫反应。以上实验结果均证实LBP可以作为佐剂增强甲流裂解疫苗经黏膜途径免疫时的免疫效力。     

志贺氏Ⅰ型痢疾杆菌O—特异性多糖与破伤风类毒素结合疫苗 …

从志贺氏１型痢疾村菌ＬＰＳ中分离纯化出料捩的,以ＡＤＨ为连接剂将其与ＴＴ结合形成Ｏ－ＳＰ－ＴＴ结合疫苗,并用此结合疫苗免疫ＮＩＨ小鼠,结果显示使用Ｏ－ＳＰ免疫后,小鼠血清中没有抗ＬＰＳ抗体产生,而用Ｌ－ＳＰ－ＴＴ免疫后鼠血清中生了抗ＬＰＳＩｇＧ和ＩｇＭ抗体,且ＩｇＧ抗体水平高于ＩｇＭ抗体;Ｏ－ＳＰ－ＴＴ免疫组等二次和第三次免疫后ＩｇＧ我有显著的升高（Ｐ〈０．０１）,但第二次和第三次免疫后血清ＩｇＭ     

LPS-based conjugate vaccines composed of O-polysaccharide from Pseudomonas aeruginosa IATS 6 and 11 bound to a carrier protein

Lipopolysaccharide (LPS) is the major surface antigen of Pseudomonas aeruginosa and elicits protective antibodies in animals. No cross reaction was observed between LPSs of P. aeruginosa International Antigenic Typing Scheme (IATS) 6 and 11 strains using rabbit polyclonal antibodies raised against the whole cells. The O-polysaccharides (O-PSs) from IATS 6 and 11, the antigenic determinant of LPS, were directly coupled to bovine serum albumin (BSA) by carbodiimide mediated condensation reaction. The molar ratios of saccharide repeating units to BSA in the prepared conjugates were 15:1 and 26:1 for IATS 6 and 11 conjugates, respectively. Mice were immunized with the conjugates emulsified with monophosphoryl lipid A (MPL), Freund, and Alum adjuvants. The conjugates emulsified with MPL adjuvant elicited the highest IgM antibody, followed by Freund. While both MPL and Freund adjuvants elicited high IgG antibody. Good correlation was observed between the IgG and IgM levels with the bactericidal activities of the sera against homologous strains. In addition, immunization of mice with the prepared conjugates emulsified with MPL and Freund adjuvants provided high protection against ten times the LD₅₀ of P. aeruginsoa IATS 6 and 11, which showed a good correlations with the IgG titer.     

Exploration of Moraxella catarrhalis outer membrane proteins, CD and UspA, as new carriers for lipooligosaccharide-based conjugates

Moraxella catarrhalis outer membrane proteins, CD and ubiquitous surface protein A (UspA), were used as carriers for M. catarrhalis detoxified lipooligosaccharide (dLOS)-based conjugates. Our study was designed to investigate the feasibility of CD and UspA as protein carriers for dLOS-based conjugates and their possible synergic effects on protection from both anti-LOS and anti-CD or anti-UspA antibody responses. Female Balb/c mice were immunized subcutaneously three times with dLOS-CD or dLOS-UspA conjugate in Ribi adjuvant. Antisera elicited by the conjugates showed high titers of specific anti-LOS antibodies with complement-dependent bactericidal activity towards M. catarrhalis strain 25238. In a mouse aerosol challenge model, mice immunized with both conjugates showed a significant enhancement of the clearance of strain 25238 from lungs as compared with the control mice. Although both conjugates elicited reduced (relative to unconjugated CD or UspA) but significant levels of anti-CD or UspA antibodies, they did not show synergetic effects with anti-LOS antibodies on the bactericidal activity or the pulmonary bacterial clearance. Nevertheless, CD and UspA are safe and effective new carriers for dLOS-based or other potential carbohydrate-based conjugate vaccines to help thymus-independent carbohydrate antigens for production of anti-carbohydrate antibodies against target pathogens.     

14型肺炎球菌荚膜多糖-破伤风类毒素结合疫苗的研制

将14型肺炎球菌的荚膜多糖(PS)与破伤风类毒素(TT)通过化学方法结合,制备成多糖-蛋白结合疫苗(PS14-TT)。用该结合疫苗免疫小鼠,在小鼠体内产生了高滴度的PS-IgG抗体和TT-IgG抗体,且再次注射后有加强应答效应,表明制备的结合疫苗保留了完好的抗原性,具有胸腺依赖性抗原的特性。     

Vaccination equally enables both genetically susceptible and resistant mice to control infection with group A streptococci

There is substantial evidence that host genetic factors are important in determining susceptibility to infection with group A streptococci (GAS). Several studies have revealed that, similarly to humans, a genetic component may be important in determining susceptibility to GAS infection in mice. Thus, C3H/HeN mice are much more susceptible to streptococcal infection than BALB/c mice. We have determined here whether vaccination makes genetically susceptible mice as capable as genetically resistant mice to control GAS infection. Resistant BALB/c and susceptible C3H/HeN mice were immunized either systemically with heat-killed GAS or through the mucosal route with an M protein-based subunit vaccine, and challenged with live bacteria. Vaccination elicited in both mouse strains similar levels of bactericidal anti-GAS IgG antibodies and also antigen-specific mucosal IgA. Vaccination provided mice of both strains with an increased and equal capacity to express immunity against GAS as indicated by the reduced level of bacteria in the organs and the ability of vaccinated mice to survive infection. Protection in vaccinated mice was dependent on the presence of T cell-dependent bactericidal antibodies as shown by the ability of serum elicited in immunocompetent mice but not of serum elicited in T cell-deficient nu/nu mice to passively transfer anti-GAS immunity. In conclusion, the results presented here demonstrated that the presence of anti-GAS specific, T cell-dependent bactericidal antibodies elicited after vaccination overcomes the innate genetic susceptibility of C3H/HeN mice and makes both resistant and susceptible mice equally capable of controlling GAS infection.     

Influence of immunization with non-genotoxic PAH-KLH conjugates on the resistance of organisms exposed to benzo(a)pyrene

Polycyclic aromatic hydrocarbons (PAH) are recognized as common environmental pollutants released into the environment from many natural as well as man-made sources, and some have been classified as potent carcinogens. The main representative of the carcinogenic PAH is benzo(a)pyrene (B(a)P) which is known to induce genotoxic effects in vitro and in vivo, detected as PAH-DNA adducts. Long-term PAH exposure may be accompanied by an immunological response with the formation of antibodies against PAH as well as against PAH-DNA adducts. This paper describes the use of four PAH-keyhole-limpet haemocyanin (KLH) conjugates for the induction of specific and cross-reactive anti-PAH antibodies and focuses on the potential protective effects of anti-PAH antibodies produced after immunization of mice. In the in vitro experiments with HepG-2 cells, the genotoxicity of the PAH-KLH conjugates and the neutralizing effect of induced anti-PAH antibodies were evaluated. The titer of specific anti-PAH antibodies in sera and the amounts of DNA adducts in liver homogenates from immunized mice were investigated in vivo. The results show that anti-PAH antibodies of class IgG were induced during immunization. All the PAH-KLH conjugates tested were non-genotoxic and did not induce detectable DNA adducts in HepG2 cells or in the liver of immunized mice. The results show that only B(a)P-specific and B(a)P cross-reactive antibodies are able to neutralize B(a)P or its activated metabolites, which was revealed by a sudden decrease in the titer of anti-B(a)P antibodies in mouse sera after exposure to B(a)P. Furthermore, the anti-B(a)P antibodies produced by immunization were effective in reducing the amount of DNA adducts in mouse livers after intraperitoneal (i.p.) exposure to B(a)P. The results suggest that immunization with PAH-KLH conjugates can protect organisms against the adverse effects of carcinogenic PAH.     

Synthetic peptide immunogens eliciting antibodies to Plasmodium falciparum sporozoite and merozoite surface antigens in H-2b and H-2k mice

Peptides representing conserved (MSA2/1A and MSA2/1B) and variant (MSA2/2, MSA2/6 and MSA2/7) regions of the merozoite surface Ag 2 (MSA2) of Plasmodium falciparum (FCQ-27/PNG isolate) were coupled to either peptide NP(NANP)5NA or peptide C(NANP)6 both of which contained the core sequence (NANP)n. The coupling was done via the N-terminus of one peptide and a cysteine residue on either terminus of the other. BL/10 (H-2b) and B10.BR (H-2k) mice were immunized with these MSA2-(NANP)n conjugates. The mice were also immunized with the unconjugated MSA2 peptides and with NP(NANP)5NA and C(NANP)6. Antibody responses were evaluated by 1) ELISA, in which the MSA2 peptides and C(NANP)6 were used as Ag; 2) immunofluorescence assays (IFAT) against intact sporozoites and merozoites; and 3) immunoblotting experiments against solubilized P. falciparum blood stage proteins. High titer antibodies to (NANP)n were elicited in both BL/10 and B10.BR mice after immunization with all the conjugates except MSA2/7-(NANP)n which gave only a very limited response in B10.BR mice. These antibodies recognized unfixed sporozoites. The conjugates also elicited antibodies to MSA2 as shown by ELISA, IFAT, and immunoblotting except for mice immunized with MSA2/1B-(NANP)n where an anti-MSA2 response was only detectable by immunoblotting. Immunization with unconjugated MSA2 peptides showed that MSA2/2 was immunogenic in both BL/10 and BR.10 mice, with MSA2/6 and MSA2/7 being immunogenic only in BL/10 mice. The antibodies elicited recognized both merozoites and the MSA2 protein. However, the antibody titers were lower overall than those seen when these peptides were used in the conjugated form. No anti-MSA2 antibodies were detected after immunization with MSA2/1A and MSA2/1B. Immunization of mice with the peptide NP(NANP)5NA produced antibodies in BL/10 (H-2b) mice only, and the immunogenicity of this preparation was poor. In contrast, C(NANP)6 produced a strong antibody response in both mouse strains. The antibodies elicited by NP(NANP)5NA and C(NANP)6 recognised sporozoites in IFAT. The MSA2 peptides studied (or their derivatives) were previously shown to be recognized by human T cells. Their immunogenic potential shows promise in that complex anti-P. falciparum responses can be elicited with simple synthetic immunogens based on these peptides.     

两种表达系统来源新冠病毒RBD蛋白免疫小鼠后的IgG抗体水平对比研究

当前新冠肺炎疫情仍在全球蔓延,给中国及世界的公共卫生安全和经济发展带来了严峻挑战。SARS-CoV-2病毒入侵机体的关键过程是刺突蛋白受体结合域RBD通过结合宿主细胞ACE2受体实现感染,而此过程与病原快速检测、疫苗以及药物干预等主要抗病毒策略的研究与开发密切相关。因此,本研究旨在比较哺乳细胞和昆虫细胞重组表达来源的新冠病毒刺突蛋白受体结合结构域RBD免疫小鼠后产生IgG抗体水平的变化,评估不同来源和不同剂量抗原的抗体滴度水平和持续时间,希望将有助于疫苗、药物以及病原检测等相关研究。通过SDS-PAGE和质谱技术鉴定出昆虫和哺乳动物细胞表达系统制备的bRBD和hRBD蛋白质的分子量略有差异,主要为糖基化修饰不同所致;流式细胞术检测发现,bRBD和hRBD与ACE2受体过表达细胞结合率分别为88.5%和92.7%,表明二者均具有较好的活性;利用Quick Antibody免疫佐剂通过肌肉注射对Balb/c小鼠进行免疫接种,设置10μg、20μg 2个免疫抗原的剂量,共接种2次,并在初次免疫后第2、4、6、8、12、24周从尾部取血,分离获得血清;酶联免疫吸附结果显示,10μg和20μg的...     

Effect of conjugation methodology on the immunogenicity and protective efficacy of meningococcal group C polysaccharide-P64k protein conjugates

Neisseria meningitidis serogroup C polysaccharide (CCPS) was conjugated to the carrier protein P64k using two different conjugation procedures, condensation mediated by carbodiimide with adipic acid dihydrazide as spacer and the reductive amination method. BALB/c mice were immunized with the resultant polysaccharide-protein conjugates and the immune response was evaluated. All conjugates assayed generated at least 10-fold higher antibody titers than the free polysaccharide. The reductive amination method rendered the best conjugate (CCPS-P64kR) that was able to elicit antibody titers statistically higher than the titer elicited by the plain CCPS (P<0.001). The sera of the group immunized with CCPS-P64kR showed a three-fold higher bactericidal response than the sera of the group immunized with the plain CCPS and they were able to protect against challenge with meningococci in the infant rat protection model. In addition, three different conjugates were obtained from polysaccharides with molecular relative sizes of 2000-4000 Da, 4000-10,000 Da or 10,000-50,000 Da, but no differences were detected in the immune response obtained against the three conjugates. Our experiments demonstrate that it is possible to generate a protective, T-cell-dependent response against CCPS using the P64k protein as carrier.     

脂多糖模拟肽13L诱导对小鼠内毒素休克的保护反应

为研究LPS 2630表位模拟肽13L是否能诱导抗脂多糖（LPS）抗体的产生、对细菌攻击及内毒素休克的保护性反应,合成了模拟LPS表位的短肽13L．用合成肽13L-蓝载体（blue carrier,BC）交联物免疫Balb／C小鼠,观察小鼠体内抗LPS抗体产生的规律,并观察免疫小鼠细菌感染存活时间,用颈总动脉插管测定技术观察免疫小鼠内毒素休克的血压变化．结果显示,合成肽13L-BSA交联物能与兔抗鼠伤寒和大肠杆菌LPS抗血清及抗鼠伤寒LPS单抗结合,证明短肽13L可模拟LPS的抗原性．用13L-BC交联物免疫可诱发小鼠体内针对大肠杆菌LPS 2630和鼠伤寒沙门氏菌LPS 7261的抗体反应,该反应可被灭活大肠杆菌及两种LPS所加强,其抗体亚类主要为IgG2a,其次为IgG2b与IgM,而IgG1与IgG3含量极低．免疫13L-BC小鼠显示对细菌攻击的抵抗,与免疫BC对照小鼠比较,其存活时间分别为（12&#177;1．3）天和（5．3&#177;0．4）天（P〈0．01）．免疫13L-BC小鼠对静脉注射LPS诱发内毒素休克的保护作用体现在血压下降幅度明显低于对照动物,在LPS 2630攻击后1、2、3及4h时两组动物血压明显差别（P〈0．05、P〈0．01、P〈0．05及P〈0．01）,而LPS 7261攻击后1、2、3及4h时两组动物血压差别则略小于LPS 2630组（P〉0．05、P〈0．05、P〈0．05及P〈0．01）．上述结果证明,LPS表位模拟肽13L交联物免疫小鼠可产生针对细菌攻击及内毒素休克的保护性效应,提示该模拟肽作为LPS交叉保护性疫苗候选的可行性．