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目的:研究戊型肝炎重组蛋白(NE2)聚乳酸羟基乙酸(PLGA)微球疫苗诱导免疫应答的情况.方法:复乳法制备微球,考察粒径分布等特性.通过间接ELISA法检测其诱导BALB/c小鼠体内IgG、IgG2a和IgGl1水平,并通过IFN--ELISPOT方法检测其诱导BALB/c小鼠体内抗原特异性免疫应答情况.结果:微球的平均粒径为7.1m.注射小鼠6周后(第4周加强免疫1次),微球疫苗诱导产生的抗戊型肝炎病毒IgG抗体水平较同剂量铝佐剂组明显升高(间接ELISA:OD450/620 10.09vs.5.32).IgG2a抗体量略高于铝佐剂组,OD450/620分别为0.17、0.04.IgG1抗体量明显高于铝佐剂组.OD450/620分别为20.48、15.00.IFN--ELISPOT结果显示,微球疫苗能很好的诱导NE2或P34肽抗原特异性免疫应答.结论:戊型肝炎重组蛋白聚乳酸羟基乙酸微球作为疫苗输送体系能明显的提高抗原的免疫原性,有很好的应用前景. 相似文献
996.
Shun Hirota Yasutaka Mizoguchi Osamu Yamauchi Teizo Kitagawa 《Journal of biological inorganic chemistry》2002,7(1-2):217-221
A resonance Raman band involving significantly the iron(III)-histidine stretching (upsilonFe-His) character is identified for metmyoglobin (metMb) through isotope sensitivity of its low-frequency resonance Raman bands, but the identification was not successful for methemoglobin (metHb) and its isolated alpha and beta subunits. A band at 218 cm-1 of natural abundance metMb exhibited a low-frequency shift for 15N-His-labeled metMb (-1.4 cm-1 shift), while the strong porphyrin bands at 248 and 271 cm-1 did not shift significantly. The frequency of the 218-cm-1 band of metMb decreased by 1.6 cm-1 in D2O, probably due to Ndelta-deuteration of the proximal His, in a similar manner to that of the upsilonFe-His band of deoxyMb in D2O. This 218-cm-1 band shifted slightly to a lower frequency in H2(18)O, whereas it did little upon 54Fe isotopic substitution (<0.3 cm-1), presumably because of the six-coordinate structure. The lack of the 54Fe-isotope shift shows that the 218-cm-1 band is specific to metMb and not due to the deoxy species. The intensity of this band decreased for hydroxymetMb and was indiscernible for cyanometMb. For metHb and its alpha and beta subunits, however, the frequencies of the band around 220 cm-1 were not D2O sensitive. These results suggest an assignment of the band around 220 cm-1 to a pyrrole tilting mode, which significantly contains the Fe-His stretching character for metMb but scarcely for metHb and its subunits. The differences in the isotope sensitivity of this band in different proteins are considered to reflect the heme distortion from the planarity and the Fe-His geometry specific to individual proteins. 相似文献
997.
Chiaki Ogino Yukinari Negi Hidenori Daido Masayuki Kanemasu Akihiko Kondo Shun’ichi Kuroda Katsuyuki Tanizawa Nobuaki Shimizu Hideki Fukuda 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2001,1530(1):23-31
A membrane-bound phospholipase D (PLD) has been identified and isolated in a soluble form from an actinomycete, Streptoverticillium cinnamoneum. The enzyme has a monomeric structure with a molecular size of about 37 kDa, being the smallest among the enzymes so far reported. The enzyme catalyzes the hydrolysis of phosphatidylethanolamine and phosphatidylserine as preferred substrates, but not the transphosphatidylation reaction of their phospholipid groups to ethanol. Together with the absence of immunochemical cross-reactivity, these enzymatic properties demonstrate that the membrane-bound enzyme is distinct from the extracellular enzyme recently characterized and cloned from the same bacterial strain [C. Ogino et al., J. Biochem. 125 (1999) 263–269] and is therefore regarded as a novel prokaryotic PLD. 相似文献
998.
RNA编辑是RNA转录过程中序列变化而引起的一种基因动态调控机制。腺苷脱氨酶(adenosine deaminases acting on RNA, ADAR)参与RNA编辑,将双链RNA中腺苷残基(A)转化为肌苷(I),接着被转录和拼接成鸟苷(G)。由ADAR催化,作用于RNA的A-I型RNA编辑是人类最常见的转录后修饰。近年来,这种修饰不仅存在于编码RNA中,在非编码RNA(noncoding RNA, ncRNA)中也逐渐被发现,如microRNA(miRNA)、小分子干扰RNA(siRNA)、转运RNA(tRNA)和长链非编码RNA(lncRNA)。这种修饰可能通过对microRNA和mRNA之间结合位点创造或破坏,进而影响ncRNA的生物起源、稳定性和靶向识别功能。目前,对这种生物现象的机制及ADAR底物,尤其是在ncRNA中的特性仍然没有得到充分的认识。主要对哺乳动物中ncRNA上的RNA编辑进行总结,并列举一些阐明其生物学功能的计算方法。 相似文献
999.
Long-Feng Lu Jing-Yu Jiang Wen-Xuan Du Xue-Li Wang Zhuo-Cong Li Xiao-Yu Zhou Can Zhang Cheng-Yan Mou Dan-Dan Chen Zhi Li Li Zhou Jian-Fang Gui Xi-Yin Li Shun Li 《PLoS pathogens》2022,18(6)
From insects to mammals, both innate and adaptive immune response are usually higher in females than in males, with the sex chromosome and hormonal differences considered the main reasons. Here, we report that zebrafish cyp19a1a (cytochrome P450, family 19, subfamily A, polypeptide 1a), an autosomal gene with female-biased expression, causes female fish to exhibit a lower antiviral response. First, we successfully constructed an infection model by intraperitoneal injection of spring viremia of carp virus (SVCV) into zebrafish (Danio rerio) and Carassius auratus herpesvirus (CaHV) in gibel carp (Carassius gibelio). Specifically, female fish were more vulnerable to viral infection than males, accompanied by a significantly weaker interferon (IFN) expression. After screening several candidates, cyp19a1a, which was highly expressed in female fish tissues, was selected for further analysis. The IFN expression and antiviral response were significantly higher in cyp19a1a-/- than in cyp19a1a+/+. Further investigation of the molecular mechanism revealed that Cyp19a1a targets mediator of IRF3 activation (MITA) for autophagic degradation. Interestingly, in the absence of MITA, Cyp19a1a alone could not elicit an autophagic response. Furthermore, the autophagy factor ATG14 (autophagy-related 14) was found interacted with Cyp19a1a to either promote or attenuate Cyp19a1a-mediated MITA degradation by either being overexpressed or knocked down, respectively. At the cellular level, both the normal and MITA-enhanced cellular antiviral responses were diminished by Cyp19a1a. These findings demonstrated a sex difference in the antiviral response based on a regulation mechanism controlled by a female-biased gene besides sex chromosome and hormonal differences, supplying the current understanding of sex differences in fish. 相似文献
1000.