TY - JOUR T1 - Elevation of serum napsin A levels in patients with hypersensitive pneumonia JF - European Respiratory Journal JO - Eur Respir J VL - 42 IS - Suppl 57 SP - P2355 AU - Tomohiro Kumamoto AU - Asami Harumatsu AU - Kouta Sakaue AU - Tsutomu Hamada AU - Masuki Yamamoto AU - Tetsurou Hamasaki AU - Keiko Mizuno AU - Ikkou Higashimoto AU - Takuya Samukawa AU - Hiromasa Inoue Y1 - 2013/09/01 UR - http://erj.ersjournals.com/content/42/Suppl_57/P2355.abstract N2 - Background: Napsin A, an aspartic protease, is mainly expressed in alveolar type II cells and renal proximal tubules. We previously reported increased napsin A levels in patients with IPF, compared with healthy controls. However, serum napsin A levels in patients with hypersensitive pneumonia (HP) have never been evaluated.Aims: To evaluate the level of napsin A in patients with HP and correlation between napsin A and other parameters.Methods: Ten patients with HP, and nineteen patients with idiopathic interstitial pneumonia (IIP) who had been admitted to our institution and thirty-three healthy controls were enrolled. Serum napsin A levels were measured by ELISA. Serum SP-A, SP-D, and KL-6 levels, pulmonary function, and immunohistochemistry for napsin A were also evaluated in patients with HP.Results: Serum napsin A levels were significantly increased in patients with HP, compared with healthy controls and IIP (331.4±198.6 ng/mL, 26.9±28.9 ng/mL, 167.1±180.7 ng/mL, respectively, p<0.05). In patients with HP, serum napsin A levels had negative correlation with DLco (r=-0.736, p<0.01). Immunohistochemistry for napsin A in patients with HP revealed high expression in alveolar epithelium cells. In the case of HP, serum napsin A levels were decreased by antigen avoidance.Conclusion: Serum napsin A might be useful as a biomarker for HP. ER -