LAMININ FRAGMENT P1 IN THE SERA OF PATIENTS WITH PULMONARY SARCOIDOSIS

Laminin is a noncollagenous component of the extracellular matrix in t he alveolar wall and may play a role in the development of fibrotic lu ng disease. Serum levels of laminin fragment Pi as well as procollagen III peptide were determined in 28 patients with pulmonary sarcoidosis and 10 healthy controls using specific radioimmunoassays. The patient s' results were compared with the clinical appearance, lung function v alues (vital capacity, total lung capacity, FEV1, transfer coefficient (KCO), and alveolar-arterial oxygen difference during exercise) and s erum concentrations of angiotensin converting enzyme and soluble inter leukin 2 receptor. Laminin levels in patients were significantly highe r than in controls but always remained within normal limits. Although there was a tendency towards higher values in patients with active dis ease and with radiographic involvement, no significant correlation was found between laminin concentration and clinical, functional or bioch emical data. In contrast, procollagen III N-terminal peptide concentra tions were elevated in 19 of 28 patients and showed a weak but signifi cant inverse correlation with parameters of restriction with significa ntly higher values in patients with active disease. In conclusion, ser um levels of laminin fragment P1 are not elevated in pulmonary sarcoid osis and do not correlate with other parameters of the disease. Yet se rum levels of procollagen III N-terminal peptide were associated with the degree of parenchymal involvement as expressed by functional distu rbance and with active disease.