皮肤致敏评价方法局部淋巴结分析及其改进方法的研究进展

Local lymph node assay and research progress in revised LLNA for evaluation of skin sensitization

皮肤致敏反应/过敏性接触性皮炎[skin sensitization/allergic contact dermatitis(ACD)],是皮肤对一种外源刺激物产生的免疫源性反应。早期,人们应用豚鼠试验来评价物质对皮肤的致敏性。如经济合作与发展组织(Organization for Economic Co-operation and Development,OECD)指导原则TG-406中所列的豚鼠最大化试验方法和Buehler法。这些方法是在激发后进行评价,实验周期较长,使用动物数较多,更重要的是评价终点是操作者的主观观察结果,缺乏客观、定量的评价指标。1989年,研究者提出用标准局部淋巴结分析试验(local lymph node assay,LLNA)进行化合物皮肤致敏性评价,该方法使用小鼠,在致敏期进行评价,实验周期短,最重要的是具有客观定量的评价指标。2002年,OECD将LLNA方法列入指导原则TG-429,成为一种新的皮肤致敏性评价方法。但该方法需要使用放射性元素,对实验人员和环境具有潜在的危害,使其应用受到一定限制,因此近年来在该方法基础上开发了一些不使用放射性元素的改进方法。2010年OECD分别将2种LLNA改进方法列入指导原则TG-442A和TG-442B。还有一些其它的评价方法正在研究或验证过程中。本文即对LLNA方法及其改进方法的研究进展进行综述。

Skin sensitization /allergic contact dermatitis（ ACD） is a skin immunogenic reaction induced by foreign particles. Guinea pig tests were initially used to evaluate the skin sensitization of chemicals,such as guinea pig maximization test（ GPMT） and Buehler test listed in the Organization for Economic Co-operation and Development（ OECD） Test Guideline 406. Guinea pig tests evaluate the skin sensitization after the challenge procedure,which have long test period,use a lot of animals and are lack of objective and quantitative end points. Researchers put forward the standard local lymph node assay（ LLNA） in 1989 for skin sensitization evaluation,which is conducted in mice in induction stage. LLNA has short test period. Most importantly,it has objective and quantitative end points. LLNA was adopted by OECD Test Guideline 429 in 2002 as a new skin sensitization evaluation method.But this method uses radioactive isotope,which has potential harmful impacts on operators and environment and is limited in application. Therefore many revised LLNA methods were developed in recent years which do not use radioactive isotope. Two revised LLNA methods were adopted as OECD Test Guideline 442 A and 442 B respectively in2010. There are many other methods which are under research or in method validation stage. This review summarized the research progress in LLNA and revised LLNA for evaluation of skin sensitization.