川崎病患儿血清中基质金属蛋白酶-9及其组织抑制物-1的变化

目的评价基质金属蛋白酶-9(MMP-9)及其组织抑制物-1(TIMP-1)在川崎病(KD)发病机制中的作用。方法采用酶联免疫吸附法(ELISA)检测33例KD患儿治疗前后血清MMP-9及TIMP-1的含量,并设置无热、发热对照组;同时检测KD患儿外周血中性粒细胞计数、C反应蛋白(CRP)等指标。结果KD组患儿急性期MMP-9血清水平较对照组升高,合并冠脉损害(CAL)者尤甚,治疗后降至正常;MMP-9的升高与外周血中性粒细胞计数、CRP呈正相关;KD患儿无论是否合并CAL,其急性期TIMP-1血清水平均高于对照组,治疗后虽有所下降,仍较对照组高;MMP-9/TIMP-1比值在KD组急性期与对照组差异无统计学意义,治疗后较无热对照组降低,与发热对照组差异无统计学意义。结论MMP-9作为一种损害因素参与了川崎病的病理生理过程,而TIMP-1可抑制其作用;MMP-9的水平可反映KD的严重程度。     

呼吸道合胞病毒感染后期Poly(I:C)诱发小鼠气道炎症及其机制研究

目的探讨呼吸道合胞病毒(RSV)感染后再发呼吸道病毒感染时诱发气道炎症及反复喘息的致病机制。方法 64只6~8周雌性BALB/c小鼠随机分为对照组、RSV组、Poly(I:C)组及RSV+Poly(I:C)组(n=16)。收集各组肺泡灌洗液(BALF),计数BALF中细胞总数及分类计数,苏木精-伊红(HE)染色观察肺部病理损伤,检测小鼠气道反应性(AHR),ELISA法检测BALF中IFN-γ、IL-4、IL-13、基质金属蛋白酸9(MMP-9)及基质金属蛋白酶抑制物-1(TIMP-1)水平。结果 RSV+Poly(I:C)组小鼠的气道炎症细胞浸润总数及AHR较其他3组显著增高(P0.05)。RSV+Poly(I:C)组小鼠的肺组织病理损伤较对照组及RSV组加重(P0.01);BALF中MMP-9水平较其他3组明显升高(P0.05),IL-4及TIMP-1显著低于RSV组(P0.01)。结论 RSV感染后病毒再感染可能引起MMP-9/TIMP-1表达失衡,加重气道炎症反应。     

婴幼儿重症肺炎血清中基质金属蛋白酶9与基质金属蛋白酶抑制物1的表达及意义

目的 探讨婴幼儿重症肺炎急性期外周血中基质金属蛋白酶9(MMP-9)及其基质金属蛋白酶抑制因子1(TIMP-1)的表达及临床意义.方法 选取2015年10月至2016年5月于郑州大学第三附属医院儿童重症监护病房住院的婴幼儿重症肺炎20例(重症肺炎组)和同期在本院呼吸病区住院的婴幼儿轻症肺炎25例(轻症肺炎组),依据病原学分为病毒性肺炎组(24例)和非病毒性肺炎组(21例),20例同期健康体检儿童为对照组.采用酶联免疫吸附法测定外周血中MMP-9和TIMP-1水平,并行潮气肺功能检查.结果 所有肺炎患儿血清MMP-9、TIMP-1和MMP-9/TIMP-1水平均显著高于对照组,重症肺炎组高于轻症肺炎组,病毒性肺炎组高于非病毒性肺炎组(均P<0.05);重症肺炎组和轻症肺炎组患儿恢复期肺功能达峰时间比(TPTEF/TE)和达峰容积比(VPTEF/VE)均明显低于对照组,重症肺炎组明显低于轻症肺炎组,病毒性肺炎组低于非病毒性肺炎组(均P<0.05);但患儿潮气量(VT/kg)的组间比较差异无统计学意义.外周血清中MMP-9水平及MMP-9/TIMP-1比值与肺功能TPTEF/TE、VPTEF/VE均呈负相关(r1=-0.459、-0.376;r2=-0.413、-0.327;均P<0.05).结论 急性期血清中MMP-9及 MMP-9/TIMP-1与婴幼儿肺炎严重程度和恢复期肺功能损伤有关,在病毒性肺炎中表现的尤为突出,可作为判断预后的监测指标.     

紫癜性肾炎患儿血清基质金属蛋白酶-2、-9及其组织抑制因子-1水平及比值变化的意义

目的探讨基质金属蛋白酶-2、-9(MMP-2、-9)及其组织抑制因子-1(TIMP-1)水平及比值变化在紫癜性肾炎(HSPN)发病机制中作用及与尿微量清蛋白(MA)的相关性。方法采用双抗体夹心ABC-ELISA法对36例单纯紫瘢、16例HSPN患儿进行血清MMP-2、-9和TIMP-1水平检测,免疫散射速率比浊法进行尿MA水平检测。与30例健康儿童对照。结果过敏性紫癜(HSP)患儿急性期血清MMP-2、-9和TIMP-1水平及MMP-2、-9/TIMP-1比值均增高,且HSPN组高于单纯紫癜组,单纯紫癜组高于健康对照组,组间差异具有显著性意义(P<0.01或<0.05)。MMP-2、-9、TIMP-1水平及比值与尿MA水平呈明显正相关(r=0·736,0.726,0·581Pa<0.01)。且尿MA异常组(Ⅱ)较正常组(Ⅰ)增高更明显,组间比较有显著性差异(P<0.01或0.05)。结论MMP-2、-9、TIMP-1水平升高及比值失衡参与HSPN的发病过程,并与尿MA形成呈正相关。     

Levels of matrix metalloproteinase-9 and its inhibitor in bronchoalveolar lavage cells of asthmatic children

Our objective was to investigate the role of matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) and their cellular sources in childhood asthma. We used 12 controls and 16 asthmatic children. The levels of MMP-9 and TIMP-1 in bronchoalveolar lavage (BAL) cells of asthmatic children were measured immunocytochemically. The positive level index, defined as the percentage of positive-stained cells × average optical density, was used to assess the expressing levels of MMP-9 and TIMP-1. The percentages of eosinophils and mast cells in bronchoalveolar lavage fluid (BALF) of asthmatic children were increased. Levels of MMP-9 and TIMP-1 in BAL cell of asthmatic children were increased significantly at about 30- and 35-fold relative to the controls, respectively. These results suggest that both MMP-9 and TIMP-1 contribute to tissue remodeling. MMP-9, which mediates the degradation of extracellular matrix (ECM), is increased significantly in the early or acute stage and may play a role in ECM degeneration. Excessive TIMP-1 may be synthesized following MMP-9 production when the body tries to repair the damage, which results in excessive deposition of ECM component.     

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目的观察中枢神经系统感染患儿血清和脑脊液(CSF)中基质金属蛋白酶(MMP-2、MMP-9)水平,并结合CSF白蛋白指数(AQ),探讨MMP-2、MMP-9在中枢神经系统感染血脑屏障(blood-brainbarrier,BBB)破坏中的作用。方法2004-09—2005-10河北医大附属二院采用ELISA法检测18例化脓性脑膜炎患儿急性期、恢复期及22例病毒性脑炎患儿急性期血清和CSF中MMP-2、MMP-9水平,并与非中枢神经系统感染对照组比较。结果化脓性脑膜炎(化脑)、病毒性脑炎(病脑)患儿急性期血清和CSF中MMP-2、MMP-9水平显著高于正常对照组(P<0·001),且化脑组显著高于病脑组(P<0·001)。化脑组恢复期患儿血清和CSF中MMP-2、MMP-9水平与对照组无明显差异(P>0·05)。结论中枢神经系统感染患儿血清和CSF中MMP-2、MMP-9水平显著增高,提示MMP-2、MMP-9可能参与了中枢神经系统感染的病理过程。     

Influenza A virus encephalopathy with symmetrical thalamic lesions

 During an epidemic of influenza A infection in Japan, a 7-year-old boy was admitted to our hospital because of high fever, convulsions, coma, and liver dysfunction on the 2nd day of a cold-like illness. His serum CPK was markedly elevated, but there was no hyperammonaemia or hypoglycaemia. His CSF showed an increased protein level, but the cell count and glucose level were normal. CT and MRI of the brain showed symmetrical thalamic lesions, and he was diagnosed with acute necrotizing encephalopathy in childhood. He had a significant increased in antibodies to influenza A H1N1 in serum and CSF, but the CSF was negative for influenza virus using virus isolation and a polymerase chain reaction assay. Conclusion Antibody production without detectable levels of influenza virus in cerebrospinal fluid suggests that virus infection occurred, but the virus did not replicate in sufficient numbers in his central nervous system. The thalamic lesion, the hallmark of acute necrotizing encephalopathy in childhood, may be initiated by a local virus infection and develop with subsequent local changes such as breakdown of the blood-brain barrier and the extravasation of blood. Received: 30 March 1999 and in revised form: 1 October 1999 / Accepted: 1 October 1999     

颅内出血足月新生儿血清基质金属蛋白酶-9及其抑制剂水平的动态变化

目的探讨颅内出血足月新生儿血清基质金属蛋白酶(MMP)-9、基质金属蛋白酶组织因子(TIMP)-1水平动态变化及其临床意义。方法采用酶联免疫吸附试验法(ELISA)分别测定30例颅内出血患儿在生后1 d内,3、7、15天血清MMP-9、TIMP-1水平及其两者比值,并与30例健康足月新生儿进行对照比较。结果颅内出血足月新生儿血清MMP-9、TIMP-1及MMP-9/TIMP-1水平明显高于对照组(P<0.01),以出生后3 d内MMP-9、TIMP-1水平及MMP-9/TIMP-1最高,7 d后开始下降,随病情恢复其水平缓慢下降,15 d部分患儿恢复正常,但与对照组比较差异仍有统计学意义(P<0.05)。小、中、大量出血患儿血清MMP-9、TIMP-1及MMP-9/TIMP-1与对照组比较,差异均有统计学意义(P<0.01);三组间比较,差异均有统计学意义(P<0.01)。结论颅内出血足月新生儿血清MMP-9、TIMP-1及MMP-9/TIMP-1水平均明显增高,可作为判定病情和评估预后的参考指标。     

川崎病患儿血清MMP-9与TIMP-1质量浓度变化及其临床意义

目的探讨川崎病(KD)患儿血清基质金属蛋白酶-9(MMP-9)及其特异性组织抑制剂1(TIMP-1)质量浓度的变化在预测发生冠状动脉病变(CAL)风险中的临床意义。方法观察组为2003~2004年在四川大学华西第二医院与四川省人民医院住院的KD患儿32例,静脉注射丙种球蛋白(IVIG)前后各抽取患儿外周静脉血1次,同时抽取20名正常体检儿童(正常对照组)外周静脉血。ELISA双抗体法测定血清MMP-9与TIMP-1质量浓度。用二维超声心动图观察心脏冠状动脉病变。结果观察组患儿急性期血清MMP-9、TIMP-1质量浓度及MMP-9/TIMP-1比值均较正常对照组儿童显著增高(P<0.01);IVIG干预前CAL组患儿血清MMP-9质量浓度及血清MMP-9/TIMP-1显著地高于非CAL组患儿(P<0.01);IVIG干预后观察组患儿血清MMP-9质量浓度与MMP-9/TIMP-1显著降低(P<0.01);IVIG干预后CAL组患儿血清MMP-9质量浓度及血清MMP-9/TIMP-1仍显著高于非CAL组患儿(P<0.05),而后者MMP-9/TIMP-1基本降至正常儿童水平;观察组患儿血清TIMP-1质量浓度在IVIG干预前后无显著变化。结论MMP-9与TIMP-1可作为KD合并CAL的一种关联因素,动态监测血清MMP-9质量浓度和(或)MMP-9/TIMP-1比值对预测KD并发CAL具有较重要临床意义。     

全反式维A酸对川崎病患儿急性期单核细胞表达基质金属蛋白酶-9及金属蛋白酶组织抑制剂-1的影响

目的 观察全反式维A酸（atRA）对川崎病（KD）患儿急性期外周血单核细胞表达基质金属蛋白酶-9（MMP-9）和金属蛋白酶组织抑制剂-1（TIMP-1）的影响。方法 分离KD患儿急性期外周血单核细胞（PBMC），分别于不同浓度atRA下培养。采用明胶酶谱法测定其MMP-9活性；酶联免疫吸附法（ELISA）检测其MMP-9和TIMP-1蛋白水平；逆转录PCR（RT-PCR）法检测MMP-9和TIMP-1mRNA表达水平。结果 atRA能在转录水平显著抑制KD患儿急性期单核细胞表达MMP-9和促进TIMP-1表达，引起细胞培养上清MMP-9／TIMP-1蛋白比值和MMP-9活性明显下降（P〈0．01），且在一定浓度范围内，下降趋势与atRA浓度呈正相关。结论 atRA能选择性调节KD患儿急性期单核细胞表达MMP-9和TIMP-1，从而抑制MMP-9活性的过度升高。     

MMP-2、MMP-9及其抑制剂TIMP-2、TIMP-1与肾脏疾病

肾脏细胞外基质(ECM)合成与降解失衡及其组织重塑导致的ECM积聚,是各种肾脏疾病发展至肾间质纤维化与肾小球硬化乃至终末期肾衰的共同病理表现.基质金属蛋白酶(MMP)是肾脏ECM降解的关键酶,金属蛋白酶组织抑制因子(TIMP)-2、-1分别为MMP-2、MMP-9内源性抑制剂.在不同类型的肾脏疾病或同一疾病的不同病理发...     

高氧、维甲酸对早产鼠肺组织基质金属蛋白酶-2、-9 及特异性组织抑制物-1、-2表达的影响

目的探讨基质金属原蛋白-2(MMP-2)、MMP-9、基质金属蛋白酶特异性组织抑制物-1(TIMP-1)和TIMP-2在高氧肺损伤中的作用及维甲酸(RA)的保护作用机制。方法建立高氧(FiO285%)暴露早产SD大鼠肺损伤模型,应用RT-PCR法检测MMP-2、MMP-9、TIMP-1和TIMP-2mRNA表达,采用明胶酶谱检测MMP-2和MMP-9酶原及活酶表达,采用Western blot技术检测TIMP-1和TIMP-2蛋白表达。结果与空气组比较,高氧暴露4、7、14d,MMP-2、MMP-9和TIMP-1 mRNA的表达均显著升高(P均<0.01),MMP-2活酶、MMP-9酶原及活酶和TIMP-1蛋白的表达明显上调(P<0.05);RA对空气暴露下它们的表达均无明显影响(P均>0.05),但不同程度下调高氧暴露后MMP-2、MMP-9、TIMP-1mRNA的表达和MMP-2活酶、MMP-9酶原及活酶的表达,进一步提高TIMP-1蛋白表达;高氧、RA对TIMP-2 mRNA和蛋白的表达均无明显影响(P均>0.05)。结论高氧暴露明显改变MMPs/TIMPs的表达,在肺泡形成关键时期,MMPs/TIMPs之间平衡关系的破坏是造成肺发育受阻和纤维化的重要因素;通过协调MMPs/TIMPs之间的表达,改善肺泡结构,降低肺纤维化程度,从而逆转高氧所致肺损伤,是RA发挥保护作用的重要机制之一。     

MMP-2 and MMP-9 and their tissue inhibitors in the plasma of preterm and term neonates

Matrix metalloproteinases (MMP) and their tissue inhibitors (TIMP) are involved in a variety of physiologic growth and development and pathophysiologic inflammatory conditions. We hypothesized that 1) MMP-2 and -9 plasma activities and TIMP-1 and -2 plasma concentrations in preterm and term neonates were dependent on the gestational and postnatal age; and 2) the respective MMP and their inhibitors were deranged in the development of bronchopulmonary dysplasia (BPD) and intraventricular hemorrhage (IVH) in preterm neonates. From 1998 to 1999, blood samples were collected from preterm neonates (25-36 wk gestation) with or without BPD and/or IVH as well as from healthy term (37-40 wk gestation) neonates during the first 28 d of life. MMP-2 and MMP-9 plasma activities were measured by zymography; TIMP-1 and TIMP-2 plasma concentrations were determined by ELISA. In neonates without BPD or IVH (n = 50), MMP-2 and MMP-9 plasma activities both appeared to be gestational age dependent, with the highest levels observed in neonates of 33-36 wk gestation. TIMP-1 plasma concentration was highest in term neonates but no gestational difference was found in TIMP-2. Only MMP-9 showed a 50% decrease after d 1 in the first postnatal month. Twelve preterm infants with BPD and/or IVH had significantly lower MMP-2 but higher MMP-9 activity and higher TIMP-1 concentration than those of corresponding neonates without BPD or IVH. These findings show the gestational age-dependent expression of plasma MMP activities and their inhibitors. MMP and TIMP may be involved in the feto-neonatal development and may contribute to the pathogenesis of BPD and/or IVH in critically ill preterm neonates.     

基质金属蛋白酶9及组织抑制物1对预测和早期诊断川崎病冠状动脉病变的意义

目的探讨川崎病（Kawasaki disease,KD）血清基质金属蛋白酶9（matrix metallopmteinase-9,MMP-9）及其特异性组织抑制物1（tissue inhibitor of metalloproteinase-1,TIMP-1）水平的动态变化在冠状动脉病变（coronary artery lesion,CAL）的预测和早期诊断中的临床价值。方法实验组KD合并CAL患儿15例,未合并CAL患儿44例,急性期静脉注射免疫球蛋白（intravenous immunoglobulin,IVIG）前后、亚急性期及恢复期各抽取1次外周静脉血,对照组为20例正常体检儿童。ELISA双抗体法测定血清MMP-9与TIMP-1含量。结果KD患儿急性期血清MMP-9含量、TIMP-1含量及MMP-9／TIMP-1均较正常对照组增高（P〈0、01）;IVIG干预后KD患儿血清MMP-9含量与MMP-9／TIMP-1比值降低（P〈0．01）;KD合并CAL患儿IVIG干预前血清MMP-9含量及血清MMP-9／TIMP-1比值高于无CAL患儿（P〈0．01）。结论川崎病冠状动脉病变患儿血清MMP-9含量与MMP-9／TIMP-1比值在急性期高于无冠状动脉病变患儿,提示MMP-9含量的急剧升高及与TIMP-1相互拮抗作用的失代偿可能是川崎病冠状动脉病变的高风险因素,动态监测血清MMP-9含量和（或）MMP-9／TIMP-1比值对预测和早期诊断川崎病合并冠脉病变具有重要的临床意义。     

肾小管间质纤维化大鼠基质金属蛋白酶-9/金属蛋白酶组织抑制因子-1的表达

目的 观察肾小管间质纤维化（TIF）大鼠基质金属蛋白酶-9（MMP-9）、金属蛋白酶组织抑制因子-1（TIMP-1）的表达，探讨MMP-9、TIMP-1在11F中的作用。方法 选用SD大鼠48只。随机分为假手术组和模型组，制备单侧输尿管梗阻（UUO）模型。采用病理及免疫组织化学等方法动态观察组大鼠d7、d14、d21梗阻侧肾脏的组织学变化和MMP-9、TIMP-1在梗阻肾小管间质中表达情况。结果 各时间点假手术组TIMP-1表达量低于模型组（Pa〈0．01），MMP-9／TIMP-1表达量比值均高于模型组（P。〈0．01）。各时间点肾小管间质损害与TIMP-1表达量呈正相关（r=0．901P〈0．01），与MMP-9／TIMP-1比值呈负相关（r=-0．937 P〈0．01）。结论 TIMP-1可能是肾间质纤维化形成促进因素之一，并参与纤维化形成的全过程。MMP-9／TIMP-1失衡参与TIF的发生机制。     

吸入糖皮质激素对支气管哮喘患儿血清基质金属蛋白酶9及基质金属蛋白酶抑制物1的影响

目的 观察吸入糖皮质激素对支气管哮喘(哮喘)患儿血清基质金属蛋白酶9( MMP-9)及基质金属蛋白酶抑制物1( TIMP-1)的影响,探讨糖皮质激素降低呼吸道重塑的机制.方法 哮喘患儿50例.给予糖皮质激素信必可都保(布地奈德/福莫特罗粉吸入剂),每吸含布地奈德80 μg、福莫特罗4.5 μg,每日2次,疗程12周,采用ELISA法测定布地奈德/福莫特罗粉吸入剂吸入前后,血清MMP-9、TIMP-1水平及肺功能指标[第1秒最大呼气量(FEV1)、最大呼气流速峰值(PEF)]的变化,并对二者进行相关性分析.结果 使用吸入糖皮质激素布地奈德/福莫特罗粉剂后,哮喘患儿血清MMP-9水平由吸入前的(43.25±13.26) μg?L-1下降至(29.62±12.47) μ.g? L-1,TIMP-1由吸入前的(119.88±32.56)μg?L-1上升至(143.15±45.36) μg?L-1,差异均有统计学意义(Pa＜0.01).PEF及FEV1变异占预计值百分比分别由吸入前的(76.15±3.26)％,(73.12±4.63)％,上升至(85.42±4.73)％,(86.49±3.72)％,PEF及FEV1变异占预计值百分比与MMP-9/TIMP-1比率均呈负相关(r=-0.402、-0.364,Pa＜0.05).结论 糖皮质激素可通过调节MMP-9/TIMP-1的平衡,降低胶原沉积,从而干预呼吸道重塑的发生.     

川崎病患儿血清中hs-CRP与基质金属蛋白酶及抑制剂联合检测的临床意义

目的：检测基质金属蛋白酶(MMP)-2、MMP-9、基质金属蛋白酶抑制剂(TIMP)-1及hs-CRP在川崎病患儿血清中的表达,并探讨其与冠状动脉损伤的关系。方法：选取151例川崎病患儿作为观察组（无冠状动脉损伤40例,有冠状动脉损伤111例）,60例健康儿童作为对照组,采用酶联免疫吸附实验(ELISA)检测血清中MMP-2、MMP-9和TIMP-1含量,应用终点散射比浊法检测血清hs-CRP的含量。结果：MMP-2,MMP-9及hs-CRP含量在冠脉损伤组及无冠脉损伤组与对照组比较差异均有显著性,在冠脉损伤组量最高（P<0.05）;川崎病患儿中MMP-2、MMP-9及TIMP-1之间的检测量呈正相关（P<0.05）。结论：MMP-2、MMP-9、TIMP-1及hs-CRP在川崎病的发生发展中可能起重要作用,MMP-2、MMP-9及hs-CRP的联合检测可能对判断病变程度有重要帮助。［中国当代儿科杂志,2009,11（12）：989-991］     

Levels of matrix metalloproteinase-9 and its inhibitor in guinea pig asthma model following ovalbumin challenge

Our objective was to investigate the role of matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) and their cellular sources in guinea pig asthma model following ovalbumin (OA) challenge. Twenty guinea pigs were divided into 2 groups: OA-challenged group were sensitized by intraperitoneal injection with OA and exposed to OA while the control group used saline in a similar manner. The positive level index (PLI), defined as the percentage of positive-stained cells × average optical density, was used to assess the expressing levels of MMP-9 and TIMP-1. The levels of MMP-9 from OA-challenged group were significantly higher than those of controls. However, no significant difference of the TIMP-1 levels between the OA-challenged group and controls were found. MMP-9 was expressed strongly in both inflammatory and structural cells while TIMP-1 was expressed weakly in inflammatory cells and structural cells. Our results implied that MMP-9 may contribute to tissue remodeling in asthma and both structural and inflammatory cells within lung tissue are the main cellular sources of MMP-9. Excessive expression of MMP-9 in the early or acute stage of asthma may be associated with the initiation of bronchial injury and inflammatory cells accumulation.     

The role of matrix metalloproteinases -9 and -2 in development of neonatal chronic lung disease

AIM: Matrix metalloproteinases (MMPs) -9 and -2 degrade type-IV collagen, a major constituent of lung basement membrane, and may have a role in the pathogenesis of neonatal chronic lung disease (CLD). We determined factors influencing MMP levels in neonatal bronchoalveolar lavage (BAL) fluid to establish whether an imbalance between MMP and its inhibitor could be implicated in CLD. METHODS: We measured MMP-9 and -2 and tissue inhibitor of metalloproteinase-1 (TIMP-1) levels in 316 BAL fluid samples from 121 babies of gestational ages 23 to 42 wk over the first 14 d of life to determine effects of gestation and postnatal age. Median MMP-9, -2, TIMP-1 and MMP-9/TIMP-1 ratio in BAL were further studied in a subgroup of 85 babies <33 wk gestation to determine their ability to predict CLD and to establish effects of antenatal corticosteroid therapy (ANCS). RESULTS: MMP-9, -2 and TIMP levels did not vary with postnatal age over the first week. Median MMP-9 levels and MMP-9/TIMP-1 ratio increased with decreasing gestation in preterm babies. The MMP-9/TIMP-1 ratio was higher in babies who developed CLD, implying a proteinase/antiproteinase imbalance, but this association disappeared when controlled for gestational age. ANCS had no effect on BAL fluid MMP or TIMP levels. CONCLUSION: MMPs may have a role in the development of lung injury and fibrosis, but estimating their levels in the first week of life does not help with prediction of CLD.