杀菌/通透性增加蛋白研究现状及应用前景

杀菌/通透性增加蛋白(BPI)是中性粒细胞内存在的一种碱性蛋白,是一个分子质量介于50～60 ku的阳性蛋白,它主要存在于人、牛、兔等哺乳动物多形核粒细胞(PN4NL)的嗜天青颗粒中及其表面,它能与革兰氏阴性菌脂多糖(LPS)结合,具有中和内毒素和杀灭细菌的作用,在革兰氏阴性菌感染的治疗方面有良好的应用前景,人类最初注意杀菌性/通透性增加蛋白是因其具有杀菌作用,但随后发现它还具有较强的颉颃内毒素的作用。近年来国外对其研究颇多,并逐渐发现其还具有很多其他功能,如抗真菌、杀灭寄生虫等作用,其被学者称为未来的“超级抗生素”。     

白头翁汤对大肠杆菌造模腹泻小鼠血清和小肠组织中MPO含量的影响

使用致病性大肠杆菌O101经腹腔注射感染小鼠建立腹泻模型,4h后给予不同剂量白头翁汤灌胃治疗,治疗3d后,小鼠禁食不禁水12h后采样测定血清和小肠组织中MPO含量。模型组小鼠血清中髓过氧化物酶(MPO)含量升高,与空白组比较差异极显著(P<0.01),小肠组织匀浆液中MPO含量升高,与空白组比较差异显著(P<0.05);白头翁汤治疗组血清MPO含量均降低,与模型组比较差异极显著(P<0.01),白头翁汤治疗组小肠组织MPO含量降低,与模型组比较差异显著(P<0.05)。白头翁汤能降低致病性大肠杆菌诱发的腹泻小鼠血清和小肠组织中MPO含量,提示其能够抑制细菌性腹泻早期炎性细胞在小肠组织的浸润。     

慢性阻塞性肺疾病患者外周血中性粒细胞凋亡的研究

目的：研究慢性阻塞性肺疾病(COPD)患者不同病期外周血中性拉细胞(PMN)凋亡及相关基因(bcl-2)的表达。方法：分离外周血中性粒细胞，流式细胞仪分析培养24h PMN凋亡及bcl-2基因表达的情况。结果：COPD患者PMN凋亡率明显低于对照组，bcl—2基因表达上调，急性期组PMN凋亡率又明显低于缓解期组，bcl-2基因表达也明显上调。结论：COPD患者PMN凋亡减少，bcl-2上调。     

乳牛L-选择素在中性粒细胞中表达与分布的定位研究

采用间接荧光标记及胶体金标记方法通过流式细胞仪和低压扫描电子显微镜，检测了L-选择素在健康泌乳中期乳牛（A组）及患金黄色葡萄球菌型临床型（B组）和亚临床型乳腺炎乳牛（C组）中性粒细胞上表达的基本规律。结果表明：三者表达L-选择素的中性粒细胞阳性率分别为97．90％、97．69％和96．67％（收集5000个细胞），组间差异不显著（P〉0．05），但患亚临床型乳腺炎乳牛的阳性率从3次测定的结果看是逐渐增加的；L-选择素表达的间接荧光强度组间差异极显著（P〈0．01）；而患亚临床型乳腺炎的乳牛组内差异也极显著（P〈0．01）；扫描电镜观察到的中性粒细胞表面脊样结构的分布及形态与流式细胞仪检测的结果具有相似性。     

猪转移因子对犬外周血中性粒细胞数量和杀菌活性的影响

无菌采犬外周血,肝素抗凝,制备不同浓度的粒细胞悬液,分别与不同浓度的大肠杆菌悬液共同培养,采用MTT法测定粒细胞的杀菌效果,确定粒细胞体外培养时杀伤细菌的最优化条件;把不同浓度的猪转移因子(Swine transfer factor,sTF)加入注射sTF前后不同时期分离的犬外周血中粒细胞与E.coli的培养系统中,测定粒细胞的杀菌能力。结果表明,当粒细胞浓度为1.3×106个/mL,E.coli浓度为6×105个/mL时,试验最能反映粒细胞的杀菌效果。当sTF浓度为1.56mg/mL时,对PMN杀菌活性的影响最大;在犬注射sTF后的第2d,中性粒细胞单独杀菌活性最好,并且此时外周血中性粒细胞的数量达到峰值。本研究结果表明,sTF不仅能够增强犬中性粒细胞的杀菌活性,还能增加犬外周血中性粒细胞的数量。     

Evaluation of Rat Neutrophil β-adrenergic Receptors by Microphysiometry

Veterinary Research Communications -     

Immunohistochemical study of matrix metalloproteinases‐2 and ‐9, macrophage inflammatory protein‐2 and tissue inhibitors of matrix metalloproteinases‐1 and ‐2 in normal,purulonecrotic and fungal infected equine corneas

Objective Determine the effects of matrix metalloproteinases (MMPs)‐2, ‐9, macrophage inflammatory protein‐2 (MIP‐2), tissue inhibitors of matrix metalloproteinase (TIMP)‐1 and ‐2 by immunohistochemical expression in fungal affected and purulonecrotic corneas. Procedure Paraffin‐embedded equine corneal samples; normal (n = 9), fungal affected (FA; n = 26), and purulonecrotic without fungi (PN; n = 41) were evaluated immunohistochemically for MMP‐2, ‐9, MIP‐2, TIMP‐1 and ‐2. The number of immunoreactive inflammatory cells was counted and statistics analyzed. Western blot was performed to detect MMP‐2, MMP‐9, TIMP‐1 and TIMP‐2 proteins. Results Matrix metalloproteinases‐2, ‐9, MIP‐2, TIMP‐1 and ‐2 immunoreactivity was identified in corneal epithelium of normal corneas, and in corneal epithelium, inflammatory cells, keratocytes, and vascular endothelial cells of both FA and PN samples. Inflammatory cell immunoreactivity was significantly higher in FA and PN samples than in the normal corneas. There was positive correlation between MMP‐2 and MIP‐2, MMP‐9 and MIP‐2, and MMP‐9 and TIMP‐1 in inflammatory cell immunoreactivity in FA samples. There was positive correlation between MMP‐9 and MIP‐2, MMP‐9 and TIMP‐2, MIP‐2 and TIMP‐1, and MIP‐2 and TIMP‐2 in inflammatory cell immunoreactivity in PN samples. Western blot confirmed the presence of all four proteins in equine corneal samples. Conclusion Increased immunoreactivity of MMP‐2 and ‐9 in FA and PN samples is indirectly related to MIP‐2 through its role in neutrophil chemo‐attraction. Tissue inhibitors of matrix metalloproteinase‐1 and TIMP‐2 are up‐regulated in equine purulonecrotic and fungal keratitis secondary to MMP‐2 and MMP‐9 expression. The correlation between MMPs ‐2 and ‐9, MIP‐2, TIMPs ‐1 and ‐2 suggests that these proteins play a specific role in the pathogenesis of equine fungal keratitis.     

厚朴酚对大鼠白细胞5-脂氧合酶活性和细胞内钙离子浓度的影响

目的：探讨厚朴酚对5—脂氧合酶活性的影响．以阐明其抗炎机理。方法：以大鼠胸腔白细胞为材料，分别用高效液相色谱法和荧光分光光谱法测定白三烯B4(LTB4)，5—羟二十碳四烯酸(5—HETE)的生成和细胞内钙离子水平。结果：厚朴酚对白细胞LTB4和5—HETE的生物合成有较强的抑制作用，其IC50值分别为8．5μmol/L和3．1μmol/L；厚朴酚还可以抑制趋化三肽(fMLP)刺激的白细胞内钙升高．但对静息状态的白细胞内钙离子水平没有明显的影响。结论：厚朴酚可以明显影响白细胞的功能，抑制炎性介质LTB4和5—HETE的生成，提示此功能与其抗炎作用机理有关。