β-defensin 2 as an adjuvant promotes anti-melanoma immune responses and inhibits the growth of implanted murine melanoma in vivo

β-defensin 2 is a small antimicrobial peptide of the innate immune system and has been thought to regulate anti-tumor immunity. However, little is known on whether β-defensin 2 could modulate melanoma-specific NK and T cell responses. In this study, we first cloned the murine β-defensin 2 gene by RT-PCR and generated the β-defensin 2 stably expressing B16 cells (B16-mBD2). Subsequently, we evaluated whether vaccination with irradiated B16-mBD2 could modulate the growth of implanted B16 cells and determined the potential mechanisms underlying the action of B16-mBD2 vaccine in modulating the growth of B16 tumors in C57BL/6. We found that vaccination with irradiated B16-mBD2, but not with control B16-p or parental B16, inhibited the development and progression of B16 tumors, and prolonged the survival of tumor-bearing mice. However, vaccination with irradiated B16-mBD2 failed to inhibit the development of B16 tumors in the CD4(+)- or CD8(+)-depleted recipients. Furthermore, vaccination with irradiated B16-mBD2 stimulated strong NK activity and promoted potent B16-specific CTL responses, accompanied by augmenting IFN-γ and IL-12, but not IL-4, responses in the recipient mice. Moreover, vaccination with irradiated B16-mBD2 promoted the infiltration of CD8(+) and CD4(+) T, NK cells and macrophages in the tumor tissues. These data suggest β-defensin 2 may act as a positive regulator, promoting anti-tumor NK and T cell responses in vivo. Therefore, β-defensin 2 may be used for the development of immunotherapy for the intervention of melanoma.     

聚谷氨酸在医药领域的应用

聚谷氨酸是一种天然的氨基酸聚合物,具有强的水溶性、生物相容性、生物可降解性、无毒等特性,是一种新型绿色环保的生物材料。聚谷氨酸作为药物载体、疫苗佐剂、医用粘合剂和组织工程材料等应用于医药领域时,可表现出更好的生物相容性、更低的生物毒性,可提高药物的靶向性,可有效提高药效,改善药物或材料的性能,因此具有十分广阔的应用前景。本文综述了聚谷氨酸在医药领域的的应用,为下一步的研究和商业化的应用提供参考。     

基因芯片技术在新基因发现中的应用

基因芯片技术是20世纪90年代中期在生命科学领域中发展起来的一种分子生物学新兴技术,是多学科的交叉融合。简要概述了基因芯片技术的产生、原理、特点、制作方法和类型,及其在新基因发现中的应用。     

Biological functions of nirS in Pseudomonas aeruginosa ATCC 9027 under aerobic conditions

Journal of Industrial Microbiology & Biotechnology - Through our previous study, we found an up-regulation in the expression of nitrite reductase (nirS) in the isothiazolone-resistant strain of...     

转染Netrin-1基因的真皮多能干细胞治疗大鼠脊髓损伤的研究

目的:观察转染Netrin-1基因的真皮多能干细胞(dMSCs)移植对大鼠脊髓损伤的修复作用。方法:取大鼠真皮组织,分离培养真皮多能干细胞,经转染Netrin-1基因和诱导,观察细胞形态变化,免疫细胞化学方法对分化细胞进行鉴定。Wistar大鼠在L4水平制成脊髓全横断损伤模型,伤处移植大鼠真皮多能干细胞或者转染Netrin-1基因的真皮多能干细胞。对大鼠进行动物行为学(BBB)评分和对损伤脊髓进行组织学检测。结果:转染Netrin-1基因的dMSCs诱导产生的神经元样细胞占总细胞数的比例为24.45±3.73%,而单独的真皮多能干细胞诱导产生的神经元样细胞占总细胞数的比例10.50±2.13%,二者差异显著(P<0.05)。BBB评分显示转染Netrin-1基因的dMSCs移植组明显高于单纯dMSCs移植组和空白对照组(P<0.05);转染Netrin-1基因的dMSCs移植组损伤脊髓结构的修复明显优于单纯dMSCs移植组和空白对照组。结论:转染Netrin-1基因的真皮多能干细胞移植较单纯dMSCs移植对大鼠脊髓损伤有更好的治疗作用。     

LL-37-haFGF融合蛋白的结构预测与生物信息学分析

目的:为开发一种多功能蛋白分子,该文采用生物信息学方法对LL-37-haFGF融合蛋白进行结构预测与分析.方法:重叠PCR技术克隆LL-37-haFGF基因,运用生物信息学软件分析LL-37-haFGF编码蛋白序列和结构.结果:LL-37-haFGF融合基因编码215个氨基酸,分子量为23.8 kDa,理论等电点为8.86,利于基因工程表达,结构分析表明其结构有利于多功能活性的保持.结论:融合基因的生物信息学分析与结构预测为研究其活性和作用机制奠定了基础.     

五种变温动物抗凝血酶和纤溶酶原相对含量比较

用免疫浊度法对进食期5～9月的鲤鱼Cyprinus carpio、鲫鱼Carassius auratus、鲶鱼Silurus asotus、中华大蟾蜍Bufo bufo gargarizans和中华鳖Pelodiscus sinensis血清中AT和PLG进行测定.结果显示:1)鲶鱼和中华鳖血清中AT的相对含量极显著高于鲤鱼、鲫鱼、蟾蜍的AT相对含量(P<0.01);2)中华鳖血清中PLG的相对含量显著高于鲤鱼、鲫鱼、鲶鱼和蟾蜍的PLG相对含量(P<0.01).结论:1)5种动物体内郁存在AT和PLG,并且抗原性和人的AT-Ⅲ和PLG相似;2)脊椎动物体内AT和PLG的生理含量与生存环境之间有一定的相关性.     

弓形虫RH株SAG1基因序列体外扩增及生物信息学分析

根据sAG1基因序列,自行设计一对寡核苷酸引物,利用PCR技术从弓形虫RH株基因组DNA中成功扩增出编码SAG1抗原的基因片段,扩增出的基因片段大小与预期长度（1006bp）相符,结果经测序验证,并利用生物信息学方法对SAG1蛋白理化性质、结构和功能进行了预测．