CAJ | 학술논문

目的观察小鼠重组白细胞介素-17A (rIL-17A)鼻腔黏膜免疫对感染肺炎链球菌(Streptococcus pneumoniae,Sp)小鼠防御素β-2(Defb2)、巨噬细胞炎症蛋白(MIP)等表达的影响,探讨rIL-17A抗肺炎链球菌感染的机制.方法 SPF级BALB/c小鼠随机分为3组:肺炎组、干预组、对照组,以鼻腔接种的方法建立肺炎模型,采用鼻黏膜免疫的方法进行rIL-17A干预.以real-time荧光定量PCR法检测肺组织Defb2、MIP-1α、MIP-2β mRNA的表达,ELISA法检测支气管肺泡灌洗液(BALF)、脾细胞以及纵膈淋巴结细胞培养上清中MIP-1α、MIP-2β、IFN-γ、IL-4的浓度,并对BALF进行白细胞分类计数和Sp菌落计数,对肺组织进行病理分析.结果 rIL-17A干预组BALF中Sp菌落数较肺炎组明显降低(2.18±0.94 vs 4.37+0.57,P＜0.01),中性粒细胞及巨噬细胞数量显著高于肺炎组(P＜0.01)；干预组肺组织Defb2、MIP-1α mRNA表达上调,其中Defb2 mRNA表达量为对照组的53.93倍,与肺炎组比较差异有统计学意义(53.93±4.80 vs 14.49±5.84,P＜0.01)；rILL-17A干预组与肺炎组比较,淋巴结细胞培养上清中MIP-1α浓度增高明显(431.80±31.57 vs 291.10±5.62,P＜0.01)；MIP-2β浓度在脾细胞和淋巴结细胞培养上清中较肺炎组显著增高(246.20±11.50 vs 183.70±10.64,508.50+20.26 vs 290.90+15.20,P＜0.01),而肺泡灌洗液中浓度变化不显著(P＞0.05)；IFN-γ浓度在BALF和细胞培养上清中均较肺炎组显著升高；ILM除淋巴结细胞培养上清中外,BALF和脾细胞培养上清中均较肺炎组显著升高(92.42±3.82 vs 80.68±4.83,106.80±8.07 vs 73.57+7.43,P＜0.01)；干预组与肺炎组小鼠支气管及血管周围炎症细胞浸润无显著差异,但干预组组织损伤较轻.结论rIL-17A可通过促进Ddb2以及MIP、IFN-y、IL-4等炎症因子的表达,增加炎症部位白细胞募集,提高Sp清除率来增强肺炎小鼠的抗感染能力.
목적 관찰소서중조백세포개소-17A (rIL-17A)비강점막면역대감염폐염련구균(Streptococcus pneumoniae,Sp)소서방어소β-2(Defb2)、거서세포염증단백(MIP)등표체적영향,탐토rIL-17A항폐염련구균감염적궤제.방법 SPF급BALB/c소서수궤분위3조:폐염조、간예조、대조조,이비강접충적방법건립폐염모형,채용비점막면역적방법진행rIL-17A간예.이real-time형광정량PCR법검측폐조직Defb2、MIP-1α、MIP-2β mRNA적표체,ELISA법검측지기관폐포관세액(BALF)、비세포이급종격림파결세포배양상청중MIP-1α、MIP-2β、IFN-γ、IL-4적농도,병대BALF진행백세포분류계수화Sp균락계수,대폐조직진행병리분석.결과 rIL-17A간예조BALF중Sp균락수교폐염조명현강저(2.18±0.94 vs 4.37+0.57,P＜0.01),중성립세포급거서세포수량현저고우폐염조(P＜0.01)；간예조폐조직Defb2、MIP-1α mRNA표체상조,기중Defb2 mRNA표체량위대조조적53.93배,여폐염조비교차이유통계학의의(53.93±4.80 vs 14.49±5.84,P＜0.01)；rILL-17A간예조여폐염조비교,림파결세포배양상청중MIP-1α농도증고명현(431.80±31.57 vs 291.10±5.62,P＜0.01)；MIP-2β농도재비세포화림파결세포배양상청중교폐염조현저증고(246.20±11.50 vs 183.70±10.64,508.50+20.26 vs 290.90+15.20,P＜0.01),이폐포관세액중농도변화불현저(P＞0.05)；IFN-γ농도재BALF화세포배양상청중균교폐염조현저승고；ILM제림파결세포배양상청중외,BALF화비세포배양상청중균교폐염조현저승고(92.42±3.82 vs 80.68±4.83,106.80±8.07 vs 73.57+7.43,P＜0.01)；간예조여폐염조소서지기관급혈관주위염증세포침윤무현저차이,단간예조조직손상교경.결론rIL-17A가통과촉진Ddb2이급MIP、IFN-y、IL-4등염증인자적표체,증가염증부위백세포모집,제고Sp청제솔래증강폐염소서적항감염능력.
Objective To evaluate the effects of intranasal administration of recombinant interleukin-17A(rIL-17A) on the expressions of β-Defensin-2(Defb2) and macrophage inflammatory protein(MIP) in pneumococcal pneumonia murine models.Methods Twenty-four BALB/c mice were divided randomly into normal control,pneumococcal pneumonia,and rIL-17A intervention groups ( n =8 ).Before intranasal (i.n) infection with Streptococcus pneumoniae,the mouse was treated with PBS or rIL-17Ai.n respectively.The mRNA levels of Defb2,MIP-1α and MIP-2β expression in lung tissue were detected by real-time quantity PCR.The numbers of bacteria and leukocytes in bronchoalveolar lavage fluid (BALF) were counted as well.And the concentrations of MIP-1α,MIP-2β,IFN-γ and IL-4 in BALF and in supematants of spleen cells and mediastinal lymph node cells were assayed by ELISA.Changes in lung tissue histopathology were observed with HE staining through light microscope.Results Neutrophil and macrophage numbers are higher in BALF of rIL-17A group,while the numbers of bacteria were lower,when compared with those in pneumonia group( P＜0.01 ).The expression of Defb2 and MIP-1α mRNA were up-regulated in lung after rIL17A treatment(P＜0.01 ).When compared with rIL-17A non-treated mice,rIL-17A treated mice secretedhigher levels of MIP-1α in lymph node cell culture supernatants( P＜0.01 ),higher levels of MIP-2β were observed in spleen cell and lymph node cell culture supernatants( P＜0.01 ),higher levels of IFN-T were detected in BALF( P ＜ 0.01 ) and culture supernatants of spleen cell ( P ＜ 0.01 ) and lymph node cell ( P ＜0.05),and higher levels of IL-4 were detected in BALF and spleen cell culture supernatant(P＜0.01 ).Comparative analysis have not detect a significant irflammatory cell increases in rIL-17A treated mice lung tissue; however the histopathological lesions were decreased.Conclusion Intranasal inoculation of rIL-17A can promote pulmonary neutrophil and macrophage recruitment and bacterium clearance,Intranasal inoculation of riL-17enhances the host defense against Streptococcus pneumoniae infection partly through increasing the expression levels of defensins,MIP,IFN-T and IL-4 etc.