目的 研究鸭IFN-γ（DuIFN-γ）在感染及控制病毒过程中的作用和机制。方法 基于βarlln的高度保守序列设计引物，通过RT-PCR方法获得了β-actin的郭分cDNA为看家基因，然后构建DuIFN-γ靶片段的竞争性内参照，建立检测DuIFN-γ基因转录的半定量竞争性RT-PCR方法。结果 建立了检测DuIFN-γ基因转录的半定量竞争性RT-PCR方法，并检测了在PHA刺激下鸭外周血单核细胞IFN-γmRNA动态变化，结果表明PHA刺激24～36h，DuIFN-γmRNA转录量最高。以此方法对用DHBvpresDNA或与IFN-γDNA共免疫DHBv感染鸭进行了测定，结果表明IFN-γ表达质粒作为DNA免疫佐剂。可以增强宿主IFN-γ的应答。结论 IFN-γ表达质粒为DNA疫苗的有效佐剂。DuJFN-γ基因转录的半定量竞争性RT-PCR方法为研究鸭IFN-γ在DHBv感染及清除中的作用和机制奠定了基础。

Sixteen pairs of two-component regulatory systems are identified in the genome of Staphylococcus epidermidis ATCC12228 strain, which is newly sequenced by our laboratory for Medical Molecular Virology and Chinese National Human Genome Center at Shanghai, by using bio-informatics analysis. Comparative analysis of the two-component regulatory systems in S. epidermidis and that of S. aureus and Bacillus subtilis shows that these systems may regulate some important biological functions, e.g. growth, biofilm formation, and expression of virulence factors in S. epidermidis. Two conserved domains, i.e. HATPase-c and REC domains, are found in all 16 pairs of two-component proteins. Homologous modelling analysis indicates that there are 4 similar HATPase-c domain structures of histidine kinases and 13 similar REC domain structures of response regulators, and there is one AMP-PNP binding pocket in the HATPase-c domain and three active aspartate residues in the REC domain. Preliminary experiment reveals that the bioinfor-matics analysis of the conserved domain structures in the two-component regulatory systems in S. epidermidis may provide useful information for discovery of potential drug target.

目的：研究两种不同的IL-15真核表达质粒对乙肝蛋白疫殁苗诱导的免殁应答的影响。方法：构建IL-15真核表达质粒（简称pIL-15）和含有IL-12信号肽的IL-15真核表达质粒（简称pIL-2s-15），CfLL-2细胞增殖实验验证两种质粒真核表达产物的生物学活性。将这两种质粒分别与HBsAg共免疫BALB/C小鼠，用ELISA法检测小鼠血清抗-HBsigG及igGl、igG2a亚类的效价。结果：与HBsAg蛋白疫苗共免疫时，pIL-15可使FIBsAg诱导的抗-HBslgG效价升高，显著高于载体pcDNA3.l与HB-sAg共免疫对照组，pIL-2s-15对HBsAg诱导抗-HBslgG效价没有明显影响。与HBsAg+pcDNA3.l组相比，FIBsAg+pIL-2s-15组和HBsAg+piL-15组诱生的抗HBsigG2a亚类均升高，但前者igG2a/lgGl比值最高，与HBsAg+pcDNA3.l组相比差别有显著性；HBsAg+pIL-15组igG2a/lgGl比值与HBsAg+pcDNA3.l组相比差别无显著性。结论：piL-15真核表达质粒可增强蛋白疫苗诱导的体液免疫应答，pIL-2s-15真核表达质粒则主要使免疫应答趋向Thl型。

目的：研究乙肝病毒核心抗原（HBcAg）DNA疫苗诱导的细胞免疫应答。方法：用表达乙肝病毒核心抗原N端144个氨基酸的重组质粒DNA（简称pHBc144）100μg免疫C57BL/6小鼠，用细胞内细胞因子染色技术检测小鼠体内抗原特异性CD8+T细胞的动态变化。结果：pHBc144免疫后抗原特异性CD8+细胞逐渐增多，在初次免疫的第14天出现第一个免疫应答高峰，此后抗原特异性CD8+细胞数量逐渐下降进入免疫记忆期并在1年内维持在稳定水平。加强免疫后在第10天抗原特异性CD8+T细胞数量达到高峰，约是初次免疫应答高峰的2倍，此后抗原特异性CD8+T细胞数量逐渐下降，但下降的速度比初次免疫应答减缓。结论：pHBc144DNA疫苗可诱导有效的细胞免疫应答。

SARS-CoV (severe acute respiratory syndrome-associated coronavirus) strain GZ50 was partially purified and inactivated with 1:2000 formaldehyde. In cell culture the inactivated virus blocked the replication of live virus by decreasing the TCID5.0 of the live virus 103.6 to 104.6 times. Inactivated GZ50 was used to immunize mice intranasally either alone, or after precipitation with polyethylene glycol (PEG), or with CpG, or CTB as an adjuvant. The titer of serum neutralizing antibodies was up to 1:640. In mice immunized with adjuvants or PEG precipitated GZ50, specific IgA was detected in tracheal-lung wash fluid by immunofluorescence. Though serum antibodies were detected, no anti-SARS-IgA could be detected in mice immunized only with inactivated GZ50. The roles of adjuvants in intranasal immunization with inactivated. SARS-CoV is discussed.