生长抑素对猕猴小肠Peyer结B细胞功能的影响  

Biological roles of somatostatin in intestinal macaque Peyer＇s patch B cells

作　　者：吴浩[1] 刘苓[1] 谭庆华[1] 李静[1] 童欢[1] 郭梅梅[1] 胡兵[1] 唐承薇[1] 

机构地区：[1]四川大学华西医院消化内科国家教育部人类疾病生物治疗重点实验室人类疾病相关多肽研究室,成都610041

出　　处：《中华医学杂志》2015年第8期606-610,共5页National Medical Journal of China

基　　金：国家自然科学基金（30330270）

摘　　要：目的 探讨生长抑素（SST）对猕猴小肠Peyer结（PP）内免疫B细胞的影响,并初步探讨其机制.方法 15只健康成年猕猴按随机数字表法分为对照组、多器官功能障碍综合征（MODS）组和MODS＋ SST组,每组5只.对照组：未手术处理;MODS组手术：沿腹正中切开,分离肠系膜上动脉后予以夹闭,60 min后松夹进行再灌注,恢复肠系膜上动脉血流;MODS＋ SST组在夹闭肠系膜上动脉前5分钟,静脉滴注SST（5 μg· kg^-1·h^-1）,持续至实验结束.术后24h后取出各脏器观察记录器官大体改变,HE染色法观察回肠组织PP形态学变化,免疫组化显示Toll样受体（TLR）4、TLR2、CD20、CD5、α4β7、黏附素细胞黏附分子1（MadCAM-1）、浆细胞抗体在小肠黏膜的分布及表达强弱变化,并采用Image Pro Plus 4.0图像分析软件进行半定量分析.结果 HE染色显示：MODS组小肠黏膜PP数量较对照组增加（4.8±2.3比1.2±0.9,P＜ 0.05）、形态增大,预防性给予SST后,MODS＋SST组与MODS组比较,PP数量减少（2.7±1.5比4.8±2.3,P＜ 0.05）,但形态大小无明显差别.免疫组化显示：MODS组B淋巴细胞CD20表达较对照组明显减少（积分光密度值,64.22±42.45比100.00±86.67,P＜0.05）,MODS＋SST组B淋巴细胞CD20表达与MODS组比较明显回升（129.02±75.04比64.22±42.45,P＜ 0.05）;3组猕猴小肠PP内B淋巴细胞均未见或极少见α4β7、MadCAM-1表达,MODS＋ SST组肠黏膜B细胞MadCAM-1表达呈强阳性;MODS组PP内TLR4及TLR2表达较对照组明显增强（93.26±10.40比25.14 ±4.56;62.06 ±9.90比15.08±2.76,P＜0.05）,MODS＋ SST组PP内TLR4及TLR2的表达较MODS组显著降低（56.60 ±6.83比93.26±10.40;35.56 ±4.71比62.06±9.90,P＜ 0.05）;对照组肠黏膜内的浆细胞主要位于固有层,MODS组黏膜固有层内的浆细胞几乎消失,MODS＋ SST组黏膜固有层内的浆细胞有所回升.结论 PP内B细胞具有执行天然免疫与获得性体液免疫的双重潜能,SST则像个开关,控�Objective To explore the effects of somatostatin （SST） on macaque intestinal Peyer＇s patches （PP） in immune B cells and explore its mechanism.Methods A total of 15 healthy adult macaques were randomized into control,MODS and MODS ＋ SST groups.Surgical procedures of MODS in macaques：For MODS group,anesthesia was maintained with diazepam （0.16 ± 0.09） mg · kg^-1 · h^-1,i.v.）.A catheter was inserted into a peripheral vein for infusing 0.9% saline and 20 g glucose （0.1-0.2 ml · kg^-1 · min^-1,i.v.gtt） for 24 h.Midline laparotomy was performed.Then superior mesenteric artery （SMA） was isolated and occluded with a microsurgical clip.After a 1-hour occlusion,clip was removed and intestinal perfusion reestablished.In MODS ＋ SST group,SST was infused intravenously with a syringe pump at a dosage of 5 μg · kg-1 · h-1 for 5 min before an occlusion of SMA until the end of experiment.Venous blood samples were redrawn and the animals sacrificed at 24 h post-ⅡR for harvesting vital organs.The changes of organs and the morphological changes of PP were detected by hematoxylin and eosin.And the expressions of TLR4,TLR2,CD20,CD5,α4β7 and MadCAM-1 were evaluated by immunohistochemical staining.Semiquantitative immunohistochemical analysis of raw data was performed with Image Pro Plus 4.0 software.Results All animals in MODS group presented with small intestines PP increased both in number and size compared with control group （4.8 ± 2.3 vs 1.2 ± 0.9,P 〈 0.05）.After prophylactic to SST,compared with MODS group,the number of PP in small intestines in MODS ＋ SST group decreased （2.7 ± 1.5 vs 4.8±2.3,P 〈 0.05）,but there was no significant difference in morphological of PP.The expression of CD20 ＋ of B-cells in MODS group was significantly lower than in normal group（integrated optical density （IOD）,64.22 ± 42.45 vs 100.00 ± 86.67,P 〈 0.05）.Interestingly,after prophylactic dosing of SST,the expression level of CD20 ＋ of B-cells elevated significantly in MODS ＋ SS

关 键 词：生长抑素 多器官功能衰竭 B淋巴细胞 Peyer结 

分 类 号：R459.7[医药卫生—急诊医学]