新生期肺炎链球菌肺炎对小鼠肺组织结构和功能的影响  

Effects of neonatal Streptococcus pneumoniae pneumonia on lung structure and function of mice

作　　者：孔潇 彭欣 李媛媛[1,2] 吴毅 王艺颖 简鼎 张光莉[2] 罗征秀[2] Kong Xiao;Peng Xin;Li Yuan-Yuan;Wu Yi;Wang Yi-Ying;Jian Ding;Zhang Guang-Li;Luo Zheng-Xiu(Institute of Pediatrics,Children's Hospital Affiliated to Chongqing Medical University/Key Laboratory of Child Development Disease,Ministry of Education/National Center for Clinical Medical Research on Child Health and Diseases/National International Scientific and Technological Cooperation Base for Major Diseases of Child Development/Chongqing Key Laboratory of Pediatrics,Chongqing 400014,China;Department of Respiratory Medicine,Children's Hospital Affiliated to Chongqing Medical University,Chongqing 400014,China)

机构地区：[1]重庆医科大学附属儿童医院儿科研究所/儿童发育疾病研究教育部重点实验室/国家儿童健康与疾病临床医学研究中心/儿童发育重大疾病国家国际科技合作基地/儿科学重庆市重点实验室,重庆400014 [2]重庆医科大学附属儿童医院呼吸科,重庆400014

出　　处：《解放军医学杂志》2021年第6期574-579,共6页Medical Journal of Chinese People's Liberation Army

基　　金：重庆市自然科学基金(cstc2020jcyj-msxmX0677);重庆市科委重点项目(cstc2017jcyjBX0049);重庆市渝中区科委项目(20200156)。

摘　　要：目的研究新生期肺炎链球菌肺炎(S.pp)对小鼠肺组织结构及功能的影响。方法50只新生期(出生后第7天)BALB/c小鼠随机分为S.pp组和对照组,每组25只。其中S.pp组鼻腔内滴注2×10~7 cfu肺炎链球菌(5μl)建立S.pp模型,对照组滴注等量PBS。感染后3周(幼年期)、5周(成年期)收集各组支气管肺泡灌洗液(BALF)及肺组织标本,HE染色检测小鼠肺组织炎症情况及肺泡结构;Masson染色检测肺泡周围胶原纤维沉积情况;ELISA检测BALF中IL-25、IL-33、胸腺基质淋巴细胞生成素(TSLP)水平;EMKA动物肺功能检测系统检测成年期小鼠肺阻力。结果与对照组比较,S.pp组小鼠发育至幼年期、成年期时辐射状肺泡计数(RAC)均明显减少[分别为(8.00±1.10)个vs.(3.53±0.35)个,P=0.018;(13.73±2.49)个vs.(4.02±0.21)个,P=0.018];平均肺泡截距(MLI)明显增加(分别为88.99±5.55 vs.127.10±9.54,P=0.006;74.45±4.84 vs.131.30±17.86,P=0.020);肺泡间隔厚度明显增厚[分别为(2.38±0.18)μm vs.(3.28±0.13)μm,P=0.002;(3.41±0.60)μm vs.(5.78±0.75)μm,P=0.023]。S.pp组小鼠发育至幼年期平均肺泡直径(MAD)明显增加[(167.00±8.85)μm vs.(193.40±5.14)μm,P=0.042],但成年期两组MAD差异无统计学意义。S.pp组小鼠发育至幼年期、成年期肺泡周围炎性细胞浸润较对照组明显增多(分别为1.68±0.24 vs.0.72±0.12,P=0.002;1.88±0.30 vs.0.67±0.23,P=0.006)。与对照组比较,肺炎组小鼠发育至成年期时BALF中IL-25、IL-33及TSLP水平均明显升高[分别为(36.16±2.80)pg/ml vs.(45.16±1.74)pg/ml,P=0.024;(52.06±1.70)pg/ml vs.(61.42±1.50)pg/ml,P=0.004;(13.32±0.74)pg/ml vs.(16.71±0.54)pg/ml,P=0.007];肺泡周围胶原纤维沉积明显增多(0.01±0.01 vs.0.44±0.01,P<0.001);当雾化吸入乙酰甲胆碱浓度达到12.5~50.0 mg/ml时气道阻力较对照组明显升高(P<0.001)。结论S.pp可诱导BALB/c小鼠平均肺泡计数减少,平均肺泡截距增大,肺泡间隔增厚,气道阻力增加,导致肺组织结构及功能异常Objective To study the effect of Streptococcus pneumoniae pneumonia(S.pp)on the lung structure and function of mice.Methods Fifty neonatal BALB/c mice(1-week-old)were randomly divided into S.pp group and control group(25 each).Mice in S.pp group were infected intranasally with 2×10~7 cfu of S.pneumoniae(D39)in 5μl to establish the S.pp model,same dosage of PBS were used synchronously to treat the mice in control group.Three and five weeks after treatment,lung tissues and bronchoalveolar lavage fluid(BALF)of the two groups were collected,HE staining was performed to detect the pathological changes of lung tissue and alveolar structure;the collagen fiber deposition around alveoli was identified by Masson staining;the levels ofIL-25,IL-33 and thymic stromal lymphopoietin(TSLP)in BALF were examined by ELISA.Five weeks after the infection,lung resistance was evaluated by EMKA pulmonary system.Results HE staining showed that,compared with control group,the radial alveolar count(RAC)decreased significantly in infancy and adult S.pp group(8.00±1.10 vs.3.53±0.35,P=0.018;13.73±2.49 vs.4.02±0.21,P=0.018),the mean linear intercept(MLI)increased obviously(88.99±5.55 vs.127.10±9.54,P=0.006;74.45±4.84 vs.131.30±17.86,P=0.020),and the alveolar septum thickness increased markedly[(2.38±0.18)μm vs.(3.28±0.13)μm,P=0.002;(3.41±0.60)μm vs.(5.78±0.75)μm,P=0.023].Compared with control group,the mean alveolar diameter(MAD)increased significantly in infancy S.pp group[(167.00±8.85)μm vs.(193.40±5.14)μm,P=0.042],but no significant difference existed between control group and adult S.pp group.The infiltration of inflammatory cells around alveoli increased obviously in infancy and adult S.pp group compared with that in control group(1.68±0.24 vs.0.72±0.12,P=0.002;1.88±0.30 vs.0.67±0.23,P=0.006).Compared with control group,the concentrations of IL-25,IL-33 and TSLP in BALF of adult S.pp group increased significantly[(36.16±2.80)pg/ml vs.(45.16±1.74)pg/ml,P=0.024;(52.06±1.70)pg/ml vs.(61.42±1.50)pg/ml,P=0.004;(13

关 键 词：新生期 肺炎链球菌肺炎 肺组织结构 

分 类 号：R563.1[医药卫生—呼吸系统]