Expression of insulin-like growth factor-I (IGF-I) in alveolar macrophages and lymphocytes obtained by bronchoalveolar lavage (BAL) in interstitial lung diseases (ILD). Assessment of IGF-I as a potential local mitogen and antiapoptotic cytokine

• Published in: Folia histochemica et cytobiologica 2006-01, Vol.44 (4), p.249-258
• Main Authors: Kopiński, Piotr, Sładek, Krzysztof, Szczeklik, Jerzy, Soja, Jerzy, Szlubowski, Artur, Balicka-Slusarczyk, Barbara, Lackowska, Bozena, Plato, Marta, Szpechciński, Adam
• Format: Article
• Language: English
• Subjects: Apoptosis; Bronchoalveolar Lavage Fluid; Female; Gene Expression Regulation; Humans; Insulin-Like Growth Factor I - biosynthesis; Lung Diseases, Interstitial - metabolism; Lung Diseases, Interstitial - pathology; Lymphocytes - metabolism; Lymphocytes - pathology; Macrophages, Alveolar - metabolism; Macrophages, Alveolar - pathology; Male; Mitogens - biosynthesis
• ISSN: 0239-8508; 1897-5631

Little is known about IGF-I expression in the alveolar lymphocytes (AL), and about local role of IGF-I in physiological conditions and in interstitial lung diseases. Bronchoalveolar lavage was carried out in patients with silicosis, asbestosis, idiopathic pulmonary fibrosis (IPF) and sarcoidosis, as well as in control subjects (n = 13, 9, 12, 56, 15, resp). Alveolar macrophages (AM) and lymphocytes (AL) were studied for (1) IGF-I, BCL-2, Fas and Fas Ligand expression and (2) cell cycle (incl. sub-G1 peak of late apoptosis) with propidium iodide (PI). Flow cytometry (FC) and immunocytochemistry were used. AL early apoptosis was detected by Annexin V FITC/PI staining. IGF-I was present in AL of all tested groups. The number of IGF-I positive AL was significantly higher in IPF (52 +/- 6.7%) and in later (II and III) stages of sarcoidosis (39 +/- 7.8 vs 16 +/- 4.0% in controls, p < 0.05). Increased BCL-2 expression in AL was detected in IPF and sarcoidosis. In all tested groups, AL were almost exclusively Fas+ T cells. Generally, a low number of AL entered apoptosis; no significant differences were found between patient groups, except decreased apoptosis rate in sarcoidosis (0.60 +/- 0.17 vs 1.15 +/- 0.33% in controls, p < 0.05). Proportion of AL positive for IGF-I was significantly correlated with parameters reflecting AL and AM cell proliferation and BCL-2 expression (e.g. AL IGF-I+ vs AM in S phase of cell cycle: r(S) = +0.50, p = 0.001), but not with apoptosis. The results show that human alveolar lymphocytes express IGF-I in normal conditions, as well as in ILD. The proportion of IGF-I+ lymphocytes was significantly increased in IPF and at later stages of sarcoidosis. In our material there was no evidence for profibrogenic or antiapoptotic activity of IGF-I. We suggest that IGF-I originating from AL may be locally active as a mitogen for alveolar macrophages and lymphocytes in ILD.