FIBRINOLYTIC COMPONENTS IN NASAL-MUCOSA AND NASAL SECRETION

We evaluated a possible role for fibrinolytic components in nasal secr etion by tissue localization with immunohistochemical techniques and b y measuring their antigen concentrations in nasal discharge by means o f ELISA and fibrin autography. Nasal mucosa was obtained surgically fr om the inferior turbinate. Urokinase-type plasminogen activator (u-PA) specific staining was observed in pseudostratified ciliated epitheliu m and was predominant in mucous cells of the seromucinous gland, while serous cells were almost devoid of stain. The pattern of staining of plasminogen activator inhibitor-2 was similar to that of u-PA. In cont rast, plasminogen activator inhibitor-1(PAI-l) immunoreactive material was localized exclusively in serous cells of seromucinous glands. Pos itive staining for tissue-type plasminogen activator (t-PA) was observ ed in endothelial cells and basal cells, which differentiate into eith er ciliated or goblet cells. Nasal secretions were partially fractiona ted by immunospecific antibody-immobilized Sepharose. Subsequent fibri n autography patterns indicated the presence of u-PA, PAI-1 and t-PA. After methacholine provocation, the level of t-PA increased transientl y but decreased rapidly with subsequent challenges. These differential stainings of fibrinolytic components and the existence of PAs and PAI -1 in the nasal discharge suggest that the fibrinolytic system may pla y a role in the movement and fluidity of nasal secretion.