Evaluation of hyaluronic acid in bronchoalveolar lavage of patients with interstitial lung disease

ERNST, G; CORDO RUSSO R; LOMPARDÍA S; MODENUTTI C; AUTERI S; GALÍNDEZ F; GRYNBLAT P; HAJOS S

Buenos Aires, Argentina

Congreso; 1° Congreso de Inmunología Franco-Argentino; 2010

Interstitial lung disease (ILD) are an heterogeneous group of parenchymal lung diseases with non infectious origin. The lack of uniformity in diagnosis has led to widely varying results in terms of morbidity and mortality. Hyaluronic acid (HA) is one of the main components of the extracellular matrix. Its function varies according to the size. Under physiological conditions HA has a high molecular weigh (HMW-HA) which possesses mainly homeostatic functions. In inflammatory diseases it can also be found as fragments with low MW  (LMW-HA). Recent reports have shown that LMW-HA acts as a damage-associated molecular pattern (DAMP). We hypothesise that ILD present alterations in HA turnover, resulting in an increase of bioactive HA fragments that exacerbate inflammation and promote changes in the structure of lung parenchyma. The aim of this work was to assess the concentration of HA in serum and bronchoalveolar lavage (BAL) from patients with ILD and determine the role of HA as a chemotactic molecule for BAL cells. Samples of patients with presumptive ILD were taken by bronchoscopy to confirm diagnosis. As controls we used BAL samples from people with healthy lungs, after surgery for tracheal stenosis. HA concentration was determined by ELISA using a HA-binding protein. HA levels were significantly increased in BAL samples of IDL patients compared to controls, (2037±171 vs 583±57) ng/ml (p£0.05). However HA levels in serum has not shown significant differences with the control. Chemotaxis of BAL cells towards HMW-HA and LMW-HA were evaluated and the results expressed as migration index (MI). Patient and control cells showed an enhanced migration to LMW-HA, (1.95 ±0.19 and 1.49±0.05) vs migration to HMW-AH (1.02±0.16 and 1.05±0.05) respectively (p£ 0.05). Our results showed a significant increase of HA levels in BAL samples from patients with ILD. Therefore HA measurement would be used as a new biomarker for diagnosis of these diseases.