左旋精氨酸通过活化树突状细胞增强约氏疟原虫感染DBA/2小鼠的Th1应答效应  

L-Arginine Enhances Thl Immune Response against Plasmodium yoelii 17XL Infection in DBA/2 Mice via Activation of Dendritic Cells

作　　者：潘艳艳[1] 刘军[1] 李莹[1] 延娟[1] 曹雅明[1] 

机构地区：[1]中国医科大学基础医学院免疫学教研室,沈阳110001

出　　处：《中国寄生虫学与寄生虫病杂志》2011年第4期247-251,共5页Chinese Journal of Parasitology and Parasitic Diseases

基　　金：国家自然科学基金(No30800962)~~

摘　　要：目的探讨左旋精氨酸(L-Arginine,L-Arg)对致死型约氏疟原虫(Plasmodium yoelii 17XL,P.y17XL)感染DBA/2小鼠Th1免疫应答的调节效应。方法 DBA/2小鼠随机分为两组,对照组和L-Arg组,每组20只,分别给予DBA/2小鼠生理盐水和L-Arg(1.5g/kg)连续灌胃预处理7d后,每鼠经腹腔感染1×10~6个P.y17XL寄生的红细胞(pRBC)。统计两组小鼠红细胞感染率和小鼠存活率。感染后第0、3和5天每组分别处死4只小鼠,取脾组织制备脾细胞悬液,流式细胞术检测CD4^+CD69^+T细胞、F4/80^+CD36^+巨噬细胞、髓样树突状细胞mDCs(CD11c^+CD11b^+)、浆样树突状细胞pDCs(CD11c^+B220^+)数量,ELISA法检测脾细胞培养上清中γ干扰素(IFN-γ)的分泌水平,Griess反应检测脾细胞培养上清中一氧化氮(NO)含量。结果与对照组(45%)比较,L-Arg组小鼠的最高红细胞感染率降到20%,自愈时间从22d缩短到20d。感染后第3天,L-Arg组小鼠CD4^+CD69^+T细胞数量[(11.27±0.97)%]、IFN-γ分泌水平[(767.86±20.56)pg/ml]、F4/80^+CD36^+巨噬细胞数量[(36.46±1.33)%]、NO产生水平[(78.66±2.89)μmol/L]、mDCs和pDCs数量[(10.02±0.37)%和(9.01±0.53)%]均显著高于对照组[分别为(7.3±0.68)%、(485.84±39.31)pg/ml、(29.61±0.47)%、(42.51±1.32)μmol/L]、(5.51±0.87)%和(5.60±0.85)%](P<0.05),而感染后第5天均无明显差异。结论 L-Arg预处理可促进DCs的活化,从而促进DBA/2小鼠于感染早期Th1免疫应答进一步有效建立。Objective To investigate the effect of L-arginine （L-Arg） during blood-stage infection by P.y17XL in DBA/2 mice. Methoda DBA/2 mice were divided into 2 groups, 20 mice in each group. Mice were respectively administered with L-Arg （1.5 g/kg, L-Arg group） and normal saline （control group） 7 days before they were infected intraperitoneally by lx 106 pRBC. Parasitemia were detected by Giemsa stained thin-smear microscopy and survival rate were monitored daily. Flow cytometry was introduced to detect the subsets of splenic CD4^＋CD69^＋F cells, F4/80^＋CD36^＋ macrophages, myeloid dendritic cells（mDCs） （CD11c^＋CD11b^＋）, plasmacytoid dendritic cells （pDCs） （CD11c^B220^＋） on day 3, 5 post infection （p.i.）. The levels of IFN-γ and NO in the supernatant of splenocytes culture were detected by ELISA and Griess reaction, respectively. Results Pre-treatment of mice with L-Arg significantly decreased the parasitemia from 45% to 20% and shortened self-cure time from 22 d to 20d after infection. The level of F4/80^＋CD36^＋ macrophages [（29.61±0.47）%], IFN-γ [（485.84±39.31）pg/ml], CD4^＋CD69^＋T cells [（7.3±0.68）%], NO [（42.51±132） Izmol/L], mDCs（CD11c＋CD11b＋） [（5.51±0.87）%] and pDCs（CD11c＋B220＋） [（5.60± 0.85）%] in L-Arg group was higher than those in control group [（36.46±1.33）%, （767.86±20.56） pg/ml, （11.27±0.97）%, （78.66± 2.89） μmol/L, 00.02±0.37）%] and （9.01±0.53）%, respectively]. Conclusion L-Arg enhances Thl immune responses during the early stage of P.y17XL infection in DBA/2 mice via the activation of DCs.

关 键 词：精氨酸 约氏疟原虫 免疫调节 TH1免疫应答 树突状细胞 

分 类 号：R382.319[医药卫生—医学寄生虫学]