title: Direct measurement of IGF-I and IGFBP-3 in bronchoalveolar lavage fluid from idiopathic pulmonary fibrosis.
abstract: Idiopathic pulmonary fibrosis (IPF) is characterized by the rearrangement of extracellular matrix and progressive increase in the amount of fibrotic tissue in the lung. IGF-I is a potent profibrogenic molecule and its bioavailability is dependent on at least 6 binding proteins called IGFBPs. Among these, IGFBP-3 is the most represented in serum and in different connective tissues. The purpose of this study was to identify and characterize IGFBP-3 in bronchoalveolar lavage (BAL) fluids. We studied 11 patients with IPF and 6 normal subjects by performing baseline pulmonary function test and BAL. IGF-I and IGFBP-3 were measured by RIA in BAL and serum. No significant differences were observed between serum IGF-I and IGFBP-3 from IPF patients and normal subjects. Instead, the direct measurement in BAL revealed a significant increase of IGF-I and IGFBP-3 in IPF patients compared to normal subjects. BAL IGF-I and IGFBP-3 concentrations were significantly related to inspiratory vital capacity (IVC) and carbon dioxide partial pressure (PaCO2): the higher the value of IVC and the lower the value of PaCO2, the higher the level of IGF-I and IGFBP-3. In conclusion, IGFBP3 and IGF-I could be important local mediators of IPF. Their direct measurement in BAL in IPF patients could be used as a clinical marker of the disease, since high levels of IGFBP-3 and IGF-I in BAL are associated to the initial phase of the disease.
authors.affiliation: Department of Physiopathology, University of Florence, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Pala
authors.forename: S
authors.initials: S
authors.lastname: Giannini
authors.forename: E
authors.initials: E
authors.lastname: Rosi
authors.forename: B
authors.initials: B
authors.lastname: Cresci
authors.forename: G
authors.initials: G
authors.lastname: Scano
authors.forename: S
authors.initials: S
authors.lastname: Mohan
authors.forename: R
authors.initials: R
authors.lastname: Duranti
authors.forename: C M
authors.initials: CM
authors.lastname: Rotella
mesh_terms: D000368:Aged; D015153:Blotting, Western; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry*; D005260:Female; D006801:Humans; D015151:Immunoblotting; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000032:analysis* / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D011658:Pulmonary Fibrosis / Q000378:metabolism*; D012016:Reference Values
chemical_list: D018972:Insulin-Like Growth Factor Binding Protein 3; D007334:Insulin-Like Growth Factor I