摘要
目的 介绍一种异硫氰酸荧光素 (FITC)标记脂多糖 (LPS)的新方法。方法 用三乙胺将 4mgLPS双链离解为单链结构后 ,再用FITC标记LPS ,通过分光光度计测定其标记率 ,并与旧式FITC标记LPS的方法进行比较。同时测定标记后FITC LPS的生物活性、刺激单核细胞分泌肿瘤坏死因子 α(TNF α)的能力及与单核细胞膜的结合能力。结果 新方法FITC标记LPS的标记率为1molLPS中FITC占 0 .980mol,原方法FITC的标记率为 1molLPS中FITC占 0 .0 2 5mol,两者比较差异有显著性 (P <0 .0 5)。而FITC LPS与标准LPS的生物学活性、刺激单核细胞分泌TNF α的能力及与单核细胞膜的结合能力差异无显著性 (P >0 .0 5)。结论 新式FITC标记LPS的方法其标记率高 ,方法简单 ,且保存LPS的生物学特性 。
Objective To introduce a new method of fluorescein isothiocyanate (FITC) labeled lipopolysaccharide(LPS).Methods LPS was made monomeric by treatment with triethylamine and labeled with FITC.The concentration of FITC in the final preparation was determined spectrophotometrically and compared with that in the old method of FITC labeled LPS.The bioactivity of FITC LPS,TNF α induction of monocytes by FITC LPS and percentage of monocyte associated FITC LPS binding to the cell surface were measured and were compared with those of native LPS.Results The new technique leaded to a highly efficient labeling (with a FITC to LPS ratio being 1∶1.02) when compared with old one (with a FITC to LPS ratio being 1∶40,P<0.05).But the bioactivity of FITC LPS,its capability of TNF α induction in monocytes and efficiency that bound to monocytes behaved indistinctively from those of native LPS(P> 0.05 ).Conclusion The method of FITC LPS had a higher labeled percentage,was safe and could maintain the bioactivity of LPS.
出处
《中华实验外科杂志》
CAS
CSCD
北大核心
2000年第3期263-264,共2页
Chinese Journal of Experimental Surgery
基金
国家自然科学基金资助项目! ( 3 9970 71 9)
