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41.
Immune response of adults to sequential influenza vaccination   总被引:1,自引:0,他引:1  
Annual immunization against influenza is recommended for numerous individuals, but the antibody response to sequential vaccination has not been well characterized. Levels of hemagglutination-inhibition antibody were measured in adults given either two or three doses of trivalent influenza vaccine at six-month intervals. A significant rise in the number of individuals with antibody titers of greater than or equal to 40 was seen for all three antigens only after initial vaccination. Repeated vaccination was necessary to maintain adequate antibody levels only to the A/Brazil (H1N1) antigen; it did not significantly affect the proportions of individuals with protective levels of antibody to either the A/Bangkok (H3N2) or the B/Singapore 222/79 antigens. These findings do not support the current recommendation for annual immunization when the vaccine formulation has not changed.  相似文献   
42.
Because 21 immunized children (13%) among the 162 confirmed Japanese encephalitis (JE) cases during 1986–1991 occurred in Taiwan, we collected 320 serum samples from Taiwan children aged 15–31 and 27–44 months immediately before the 1st dose (n = 41) and 1–3 months after the 2nd dose (n = 78, 27 pairs), and immediately before (n = 58) and 1–3 months after the 3rd dose (n = 143,44 pairs) to determine neutralization antibody (Nt Ab) against the Nakayama (N) and Beijing-1 (B) strains and two Taiwan wild type JE viruses (JEV): CC-27 and CH-1392. Our Nt results showed that (1) B vaccine stimulated a better homologous Ab response than N vaccine for Nt Ab seropositivity rate (NASR), produced a higher level of Nt titer after the primary immunization [2 doses = 100% vs. 91%, geometric mean titer (GMT) = 115 vs. 22], had a greater booster effect (3 doses: 100% vs. 95%; GMT = 320 vs. 33), and showed a better capability to neutralize two local Taiwan JEV strains, particularly only after 3 doses (ave. NASR for B vs. N = 90% vs. 10%; and GMT for B vs. N = 154 vs. 1); (2) the two wild type JEV strains had different plaque morphology and antigenic variation and the CC-27 strain was not neutralized as well as the CH-1392 strain after 3 doses of vaccine (BBB or NNN or NNB); and (3) 30% of the children had lost JEV Nt Ab one year after the 2nd dose of N vaccine and natural infection with JE virus did occur among those children after immunization. In conclusion, (1) three doses of mouse-brain vaccine are the minimum requirement to protect children against the local Taiwan JEV; (2) the best strain for a JE vaccine depends on level of Nt Ab it induced, the molecular epidemiology and antigenic variation of the JEV in each local area; and (3) future vaccine must produce better B- and T-cell memory. © 1994 Wiley-Liss, Inc.  相似文献   
43.
The development of the antibody repertoire in newborn mice is greatly influenced by idiotypic network interactions. It has been demonstrated that anti-idiotypic antibodies either directly injected or transferred from the mother may alter the repertoire for life. For an elucidation of the underlying mechanisms we have analyzed the primary immune response to 2-phenyl-5-oxazolone (phOx) coupled to chicken serum albumin (CSA) in BALB/c mice after complete disappearance of maternal antibodies which originated from different stages of affinity maturation. Depending on the serum titers of the mothers after primary (1° mo), secondary (2° mo) or tertiary (3° mo) immunization, maternal anti-phOx IgG persisted in F1 mice for up to 9 months. In addition, F1 mice born to 2° mo developed – even without immunization – an anti-phOx IgM titer which reached levels similar to an antigen-induced primary response. An enhancement of the early primary anti-phOx as well as anti-CSA response was seen in F1 mice born from 1° mo, whereas the response was delayed when born to 2° mo and 3° mo. The antibody titers in the latter group of mice remained at a lower level for 3 months. In contrast, mice of the F2 generation which received a smaller amount of the same collection of maternal antibodies as F1 mice from 3° mo exhibited a quite different primary response: (i) They showed an earlier onset in their anti-CSA response. (ii) Whereas normally a plateau in antibody titer was reached by the 4th weak after immunization, in 55 % of the F2 mice a prolonged increase of the anti-phOx and anti-CSA antibody titers was observed. At 12 weeks after antigenic challenge, titers reached plateau levels of 6 × 105 which were never before seen in a primary phOx or CSA response. Thus, depending on its own immunological experience, the maternal immune system induces a state of memory in the offspring which results in a faster and/or enhanced immune response in the F1 and F3 generations.  相似文献   
44.
目的:观测双价痢疾工程菌苗滴鼻免疫小鼠后,不同时间、不同部位淋巴组织细胞表型的变化,探讨痢疾菌苗滴鼻免疫对黏膜和系统免疫应答的影响。方法:BALB/c小鼠随机分为3组,每组30只,分别以FSM-2117和FS-5416痢疾菌苗经滴鼻途径免疫小鼠4次,菌量依次为5×106、1×107、4×107和4×107CFU/只,对照组给予PBS,间隔2 wk。4次免疫后7、30和90 d活杀,分离NALT、鼻通道、脾、小肠PP结淋巴细胞,采用流式细胞术检测其淋巴细胞表型的变化。结果:4次免疫后7 d,小鼠鼻相关淋巴组织(NALT)、鼻通道(NP)和Peyer’s结(PP)淋巴细胞中,CD3 T细胞数均显著增加,其中以CD4 T细胞增加为主。FSM-2117免疫组的脾细胞中B220 细胞显著增加;而FS 5416免疫组的脾细胞中CD3 T细胞显著增加。4次免疫后30 d,NALT、NP和脾淋巴细胞仍出现上述变化;而90 d,仅NALT和NP淋巴细胞出现上述同样变化。结论:两株双价痢疾菌苗滴鼻免疫小鼠后,能有效地诱导黏膜和系统免疫应答,且持续时间较长,但该免疫应答的减弱是从距免疫部位较远的部位而开始的。  相似文献   
45.
目的调查本地某乡镇一次麻疹疫情的流行强度,描述其三间分布,分析暴发原因及影响因素。方法现场流行病学调查,酶联免疫捕获法检测麻疹IgM抗体,作免疫空白与麻疹发病关联的病例对照研究。结果2006年5月~7月,该乡镇发生30例麻疹局部暴发,其中29例儿童麻疹,1例成人麻疹,5例麻疹IgM抗体阳性。发病地点主要为小学和和幼儿园,罹患率分别为7.94%、7.87%。免疫空白与发病关系研究表明,初种免疫空白OR=7.2,X2=6.84,复种免疫空白OR=11.0,X2=9.48;影响免疫空白形成的社会因素调查,未接受麻疹疫苗初种或复种儿童的父母双亲常年在外务工占82.4%(28/34),有麻疹疫苗接种史儿童的父母常年在外务工占35.3%(12/34),二者有统计学差异(X2=15.54)。结论免疫空白是麻疹暴发形成的重要因素,农村儿童的父母常年在外务工形成隔代抚养教育对计免工作有负面影响。  相似文献   
46.
Injection of microparticle-encapsulated DNA elicits immune responses to plasmid-encoded antigens in mice and humans. Cytochrome P450 CYP1B1 (CYP1B1) is a member of the CYP1 P450 enzyme family that is overexpressed in a variety of solid tumors. The work described herein was performed to study the kinetics of stimulating T cell responsiveness with an encapsulated DNA encoding CYP1B1 and provides support for the clinical development of this formulation. Immunization of HLA-A2/Kb transgenic mice with human CYP1B1 encoding plasmid DNA formulated in poly(lactide-co-glycolide) (PLG) microparticles elicits CD8+ T cells that respond to human CYP1B1-positive target cells. The duration of the immune response, the effect on the immune response of multiple injections, and the safety of repeated injections were studied. These results show that the PLG-encapsulated DNA therapeutic elicits durable immune responses to CYP1B1, the responses are dependent on repeat immunization, and that the formulation is well tolerated.  相似文献   
47.
The frequency of human platelet antigen-1 (HPA-1) to HPA-11w (excluding HPA-8w) and HPA-15 systems was studied in four sub-Saharan populations: Beninese, Congolese (Democratic Republic of Congo Kinshasa), Cameroonians, and Aka pygmies (Central African Republic). No report of HPA prevalence has previously been published concerning these populations which are characterized by the highest HPA-2b gene frequencies of any reported to date (Aka 0.393, Benin 0.292, Cameroon 0.237, and Congo 0.224) and at lesser degree HPA-5b (Aka 0.405, Congo 0.268, Cameroon 0.254, and Benin 0.182). This study is of great importance (i) particularly in the context of the diversity caused by the population migrations, we may observe today in our hospitals (ii) to confirm that the Pygmy population with distinctive frequencies (absence of the HPA-1b, HPA-2b, and HPA-5b highest frequencies) is an isolated population.  相似文献   
48.
C3d-P28增强乙型肝炎病毒特异性基因免疫效果的研究   总被引:3,自引:0,他引:3  
目的 观察补体C3d P2 8对基因免疫的调节作用及其不同拷贝数对调节作用的影响 ,为增强基因免疫效果寻求新方法。方法 PCR法获得补体C3d P2 8编码基因并以头尾串连方式将1~ 4拷贝C3d P2 8编码基因克隆至pVAON33,构建pVAON33 P2 8.[1~ 4 ]重组质粒 ,然后将HBV preS2 S编码基因分别插入pVAON33和pVAON33 P2 8.[1~ 4 ]质粒获得pVAON33 S2 S和pVAON33 S2 S P2 8.[1~ 4 ]重组质粒。肌肉注射各重组质粒DNA(每只 10 0 μg 10 0 μl)初次免疫小鼠 ,并以pVAON33为对照 ;12周后皮下注射HBsAg蛋白加强免疫各组小鼠 ,ELISA法检测免疫小鼠血清特异性抗 HBs IgG。结果 pVAON33 S2 S重组质粒免疫小鼠可诱导产生特异性抗 HBs IgG ,含不同拷贝C3d P2 8编码基因的重组质粒可诱导更高的特异性抗体 ,其中pVAON33 S2 S P2 8.4重组质粒诱导的抗体水平最高 (P <0 .0 1)。蛋白加强免疫后 ,含C3d P2 8编码基因重组质粒免疫组抗 HBs IgG迅速上升 ,并明显高于pVAON33 S2 S重组质粒免疫组 (P <0 .0 5 ) ,pVAON33 S2 S P2 8.4重组质粒诱导的抗体仍维持最高水平。结论 不同拷贝的C3d P2 8能不同程度地增强HBV preS2 S基因免疫诱导的特异性体液免疫及其蛋白加强后的回忆反应 ,其中 4拷贝C3d P2 8的增强作用较为显著。  相似文献   
49.
Ten years after transplacental immunization with tetanus toxoid, the antibody responses of the immunized children to a booster immunization with 5 Lf tetanus toxoid did not differ from those of the control children. The tetanus toxoid-stimulated lymphocyte proliferative responses showed that there was no tolerance to tetanus toxoid induced by transplacental immunization, and the stimulation indices suggested that there may be some long-term memory for tetanus toxoid among the T lymphocytes in children who had been transplacentally immunized by maternal immunization with a standard dose of tetanus toxoid.  相似文献   
50.
用带结肠癌HRT-18细胞株的BALB/c(nu/nu)小鼠的血清,体处免疫BALB/c小鼠的脾细胞.再与Sp2/0细胞融合,经免疫荧光法在人结肠癌石蜡切片上筛选出一组抗结肠癌的单克隆抗体;A15-6,C13-11,H16-8。间接免疫酶法显示这组单抗对结肠癌的阳性率为69%-72%。免疫组化的特点为:癌巢分泌物及其接触的细胞膜顶端多为阳性反应,其他部位呈阴性反应。3抗体对其他类型的组织无反应。可见,这是一组针对血液循环中肿瘤相关抗原的单克隆抗体,有较好的器官特异性,可能有益于大肠癌的临床血清学检测。  相似文献   
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