目的 利用DHBV感染鸭模型，研究鸭IFN-γ真核表达质粒作为免疫佐剂对DNA疫苗诱导免疫应答的影响和预防DHBV感染的作用。方法 用DuIFN-γ真核表达质粒与DHBpreS/SDNA疫苗共免疫，或用DHBpreS/SDNA疫苗单独免疫正常幼鸭，检测经免疫前后鸭PBMC表达DuIFN-γ的mRNA水平（半定量竞争性RT-PCR）、诱生的抗体水平（ELISA）、病毒攻击免疫鸭后血清和肝脏中的病毒DNA变化（斑点和Southern印迹核酸杂交）。结果 IFN-γ表达质粒作为免疫佐剂，可以增强DNA疫苗诱导的鸭PBMCIFN-γ的mRNA表达水平。用大剂量病毒攻击免疫鸭的结果显示，用DuIFN-γ表达质粒和DHBpreS/SDNA疫苗共免疫鸭清除DHBV的速度，明显比仅用DHBpreS/SDNA疫苗免疫鸭清除病毒的速度快，肝脏中DHBV总DNA和共价闭环DNA（cccDNA）的量也低于DHBpreS/SDNA单独免疫组。结论 IFN-γ真核表达质粒作为免疫调节佐剂在DNA免疫中具有潜在的应用价值。

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 研究中药复方ZL-1在鸭己型肝炎病毒（DHBV）持续性感染模型中抗嗜肝DNA病毒的作用。方法 应用中药复方ZL-1治疗实验感染鸭，口服给药，剂量500mg•kg-1•d-1，分2次服用，连续4周。采用斑点分子杂交和southem印迹杂交检测治疗后感染鸭血清和肝脏中病毒的动态变化。同时以拉米夫定及安慰剂作为对照组。结果 复方药物ZL-l治疗后血清中DHBvDNA均数从3.6×1010拷贝/ml下降至0.9×1010拷贝/ml（P<001），抑制病毒率为75%，但尚不能清除病毒血症，肝组织中总DHBvDNA和DHmv超螺旋型DNA量无明显减少，停药观察2周，病毒复制反弹不明显。拉米夫定治疗后可显著降低病毒血症（P<0.01），抑制病毒率达99%，同时肝组织中总DHBVDNA和DHBV超螺旋型DNA量减少，但停药观察2周，病毒复制反弹明显。安慰剂组（口服生理盐水）治疗前后病毒水平的差异无显著性（P>0.05）。结论 复方药物ZL-1治疗4周可使感染鸭病毒血症降低。但不能清除病毒血症，肝脏中病毒复制水平也无显著下降。

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。

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.