[Studies on insulin-like growth factor-I expression in human lower airways]

Antisense techniques that inhibit intracellular expression of insulin-like growth factor-I (IGF-I) were efficient in gene therapy of some tumor diseases. IGF-I in the airways is considered to induce lung fibrosis in interstitial lung diseases, inhibit apoptosis of epithelial cells and participate in local carcinogenesis.

The aim of the study was--by examining the IGF-I expression in the lower airways--to evaluate preliminary the efficacy of anti-IGF-I antisense technicques in the treatment of airways diseases.

The IGF-I expression was examined in the reverse transcriptase--polimerase chain reaction (RT-PCR) applied to A549 human cell line, that is representative for lower airway epithelium and exemplifies the model of bronchioloalveolar adenocarcinoma. IGF-I expression in non-neoplastic lower airways cells was assessed by immunocytochemical staining (anti-IGF-I) in cytological materials originating from bronchoalveolar lavage (BAL) of sarcoidosis and asbestosis patients and in individuals free of lung pathology.

The IGF-I expression was detected in A549 cells with use of RT-PCR method (3 independent probes). In BAL cytological specimens the appearance of IGF-I was found, mainly in alveolar macrophages (62 +/- 6, 5 in sarcoidosis vs. 36 +/- 6 in controls, p=0,09), as well as in BAL lymphocytes.

Summing up, the antisense technicques, blocking the intracellular IGF-I expression may be potentially useful in treatment of selected lower airways, both tumor (non-small cell lung carcinoma) and non-tumor (ILD complicated with lung fibrosis) conditions.