Antileucoproteas e inthedeveloping fetal lung

Itprobablyprotectsthebronchialliningfromdamagebyelastase, whichhasbeenshownto haveaharmfuleffectontheairwayepitheliumofexperimen-tal animals"12 aswellasonhumanairwayepitheliumin vitro.'314 The results ofthis investigation indicatethat protection against protease is established in thesubmucosal glands relatively early during lungdevelopment.In the adult distal airways antileucoprotease hasbeenlocalised not only in Clara andgoblet cells butalso in association with elastic fibres,25 anda recentmorphometricstudy suggests that it is quantitativelyincreased when bronchioles are inflamed and theiralveolar attachments damaged.6 Ifantileucoproteaseoccursindistalairwaysonlyinresponsetodiseaseandisabsentinhealth,itcouldbearguedthatit ismerelyanon-specificcomponentoftheinflammatoryresponse.But as it is present