PT  - JOURNAL ARTICLE
AU  - C. Hermans
AU  - M. Petrek
AU  - V. Kolek
AU  - B. Weynand
AU  - T. Pieters
AU  - M. Lambert
AU  - A. Bernard
TI  - Serum Clara cell protein (CC16), a marker of the integrity of the air-blood barrier in sarcoidosis
AID  - 10.1183/09031936.01.99102601
DP  - 2001 Sep 01
TA  - European Respiratory Journal
PG  - 507--514
VI  - 18
IP  - 3
4099  - http://erj.ersjournals.com/content/18/3/507.short
4100  - http://erj.ersjournals.com/content/18/3/507.full
SO  - Eur Respir J2001 Sep 01; 18
AB  - To test the hypothesis that sarcoidosis is associated with an intravascular leakage of lung epithelium secretory proteins, the occurrence and determinants in serum of sarcoid patients of CC16, a small size and readily diffusible lung-specific protein of 16 kDa secreted by bronchiolar Clara cells, was investigated.CC16 was measured by a sensitive latex immunoassay in the serum of 117 patients with established sarcoidosis and of 117 healthy subjects matched for age, sex and smoking status. Stepwise regression analysis was used to identify extrapulmonary variables of CC16 changes in serum. These changes were then compared with biochemical and cellular parameters in bronchoalveolar lavage fluid (BALF) as well as with the number of CC16 immunostaining cells on bronchial or pulmonary biopsy samples.CC16 concentration in serum of sarcoid patients was significantly increased, compared to their matched controls (25.9±16.2 versus 13.9±5.2 µg·L−1). In nonsmoking patients without significant renal impairment, CC16 in serum increased with the severity of the chest radiograph and computed tomography changes, and was on average 50–100% higher when parenchymal involvement was present. Sarcoid patients had, however, normal levels of CC16 in BALF and an unchanged number of CC16-immunopositive cells in lung biopsy samples, suggesting that an increased secretion of CC16 in the sarcoid lung is very unlikely, and that the elevation of CC16 in sarcoidosis results from an increased intravascular leakage of the protein across the air-blood barrier.The present study suggests that CC16 in serum might provide a useful tool to noninvasively evaluate the damage and increased permeability to proteins of the air-blood barrier associated with sarcoidosis.This study was supported by the European Union (EV4-CT96-0171), the National Fund for Scientific Research (Belgium) and the Czech Ministry of Health (Grants IGA NI5275-2 and CEZ J14/98.151100002). C. Hermans is Research Fellow and A. Bernard Research Director of the National Fund for Scientific Research.