Upregulation of stromal cell derived factor-1α in collagen vascular diseases-associated interstitial pneumonias (CVDs-IPs)

Abstract

Objective We speculated that distinct angiogenic profiles are involved in idiopathic interstitial pneumonias (IIPs) in comparison with interstitial pneumonias associated with collagen vascular disease (CVD-IPs). This hypothesis was investigated by measuring the expression of a cardinal biologic axis, the vascular endothelial growth factor (VEGF)–stromal derived growth factor [SDF-1α, transcripts 1 and 2 (TR1 and TR2)] and receptor, CXCR4 and the angiogenetic receptors CXCR2 and CXCR3 in bronchoalveolar lavage fluid (BALF) in both conditions. Methods We studied prospectively 25 patients with fibrotic IIPs (f-IIPs) [20 with idiopathic pulmonary fibrosis (IPF) and 5 with idiopathic non-specific interstitial pneumonia (NSIP)] and 16 patients with CVD-IPs. mRNA expression was measured by Real-Time RT-PCR and protein was evaluated by Western Blotting. Results A significantly greater value has been detected in SDF-1α-TR1 mRNA expression levels of CVD-IPs ( p = 0.05) in comparison with IPF group. A similar trend has been also detected in protein expression in favor of CVD-IP group. In addition, VEGF mRNA levels have been found significantly increased in CVD-IPs in comparison with the NSIP group ( p = 0.05). No significant difference has been found in SDF-1α-TR2–CXCR4 mRNA and CXCR2–CXCR3 between the two groups. Conclusion These results showed increased expression of SDF-1α in CVD-IPs, suggesting different angiogenic procedures. Further studies are needed in order to better explore the angiogenetic pathway in these disorders.