束缚应激条件下S180荷瘤小鼠Th1/Th2细胞因子失衡与肿瘤的生长(英文)

Th1/Th2 cytokine imbalance and the growth of cancer in S180 cancer-loaded rats under restriction stress

背景:束缚是研究心理应激的可靠方法。束缚应激可以通过下丘脑-垂体-肾上腺轴抑制T细胞免疫。目的:观察束缚应激状态下小鼠体内Th1/Th2平衡的改变以及荷瘤小鼠肿瘤生长情况,并试图发现心理应激对肿瘤细胞生长的影响。设计:以实验动物为研究对象的对照研究。单位:北京中医药大学基础医学院微生物学与免疫学教研室。材料:实验在北京中医药大学基础医学院免疫学实验室开展。选择鼠龄6～8周的昆明种小鼠为实验对象。购进后适应性饲养3d,称质量,并按体质量顺序编号,剔除体质量最大和最小的个体,再随机分入4个实验组中。分组后每组有小鼠16只(雌雄各8只),体质量18～20g。方法:取腹腔传代第7天的肿瘤细胞S180,用生理盐水洗涤后,用RP-MI1640细胞培养基调细胞密度至1×1010L-1,在单纯肿瘤组和肿瘤束缚组小鼠右腋皮下注射0.2mL/只。同时在正常对照组和单纯束缚组相同部位注射生理盐水0.2mL/只,接种后将单纯束缚组和肿瘤束缚组小鼠用特制小管限制活动,8h/d。10d后处死小鼠,剥取肿瘤和胸腺并分别称其质量,计算胸腺指数,分别采用四甲基偶氮唑盐比色法和丝裂原激活淋巴母细胞法检测脾T细胞增殖及产生Th1型细胞因子白细胞介素2、干扰素γ的能力,并取血清用酶联免疫吸附法检测Th2型细胞因子白细胞介素4、白细胞介素10的?

BACKGROUND:Restriction is a reliable means in the study of psychological stres s,and restriction stress can suppress cellular immunity of T lymphocytes through hypothalamus pituitary adrenal axis. OBJECTIVE:To investigate the changes of Th1/Th2 balance due to restriction st ress in cancer loaded rats and the growth of cancer so as to explore the effect of psychological stress on cancer cells. DESIGN:Case control study based on experimental animal as subjects. SETTING:Teaching and Research Department of Microbiology and Immunology of Be ijing University of Traditional Chinese Medical. MATERIALS:This study was carried out in the Immunology Laboratory of Beijing T raditional Chinese Medical University.Kunming rats of 6-8 weeks old were select ed.They were raised for 3 days before experiment to adapt to the environment and numbered according to their weight.Rats with the highest and lowest body weight were excluded,and the rest were randomly divided into 4 groups of 16 rats(8 mal e rats and 8 female rats) weighing 18 to 20 g. METHODS:S180 cancer cells were collected at 7 days of celiac subculture and r insed with normal saline before made into cell suspensions of 1 ×1010 L-1 with RPMI 1640 medium.Rats were given subcutaneous injection of 0.2 mL cell suspensi on at the right axilla in cancer group and cancer combined restriction group.Me anwhile,the same dosage of normal saline was used instead in normal control grou p and pure restriction group in the same way.After injection,movements of rats i n pure restriction group and cancer combined restriction group were restricted in specially made tubes for 8 hours a day.Ten days later rats were killed to re move the tumor and thymus which were then weighed for calculating the thymus ind ex.MTT colorimetry and mitogen activated immunoblast method were used to examin e the proliferation of spleen T lymphocytes and the production of Th1 type cyto kines,such as interleukin 2(IL 2),interferon γ(IFN γ);meanwhile,ELISA tech nique was used to detect the level of serum Th2 type cytokines,such as interleu kin 4(IL 4) and interleukin 10(IL 10). MAIN OUTCOME MEASURES:Primary outcomes:effect of restriction stress on T lymp hocyte' production of IL 2 and interferon γ,and on IL 4 and IL 10 as well a s the effect in promoting the cancer growth in cancer loaded rats.Secondary out comes:effect of restriction stress on T lymphocyte proliferation and thymus ind ex. RESULTS:Restriction stress significantly increased the cancer weight and decre ased thymus index and the proliferation of spleen T lymphocytes.Meanwhile,IL 2 and IFN γproduced by spleen cells also decreased,with serum IL 4 and IL 10 l evel obviously increased in cancer loaded rats. CONCLUSION:The cellular immunity of cancer loaded rats was obviously suppres sed due to restriction stress,which was presented by decreased Th1 type cytokin e production and increased Th2 type cytokine production,resulting in Th1/Th2 cy tokine imbalance towards Th2.It may be the important mechanism of its promoting effect on the growth of cancer.