TY - JOUR T1 - Lymphangiogenic factors are associated with the severity of hypersensitivity pneumonitis JF - BMJ Open Respiratory Research JO - BMJ Open Resp Res DO - 10.1136/bmjresp-2015-000085 VL - 2 IS - 1 SP - e000085 AU - Masahiro Yamashita AU - Takashi Mouri AU - Miyuki Niisato AU - Hiroo Nitanai AU - Hitoshi Kobayashi AU - Masahito Ogasawara AU - Ryujin Endo AU - Kazuki Konishi AU - Tamotsu Sugai AU - Takashi Sawai AU - Kohei Yamauchi Y1 - 2015/09/01 UR - http://bmjopenrespres.bmj.com/content/2/1/e000085.abstract N2 - Background Antigen presenting cells play a pivotal role in the adaptive immune response in hypersensitivity pneumonitis (HP). It was hypothesised that lymphangiogenesis is involved in the pathophysiology of HP via cell transport.Objective To determine the clinical significance of lymphangiogenic factors in HP.Methods Levels of vascular endothelial growth factors (VEGF)-A, VEGF-C, VEGF-D and CCL21 in the serum and bronchoalveolar lavage fluid (BALF) were measured in 29 healthy volunteers, 14 patients with idiopathic pulmonary fibrosis (IPF) and 26 patients with HP by ELISA. Additionally, immunohistochemical analyses were performed using lung specimens of patients with HP (n=8) and IPF (n=10).Results BALF VEGF-D levels were significantly elevated in patients with HP compared to the other groups. BALF VEGF–D levels in patients with HP correlated significantly with the BALF total cell and lymphocyte counts (r=0.485, p=0.014 and r=0.717, p<0.0001, respectively). BALF VEGF-C and CCL21 levels were increased in patients with HP compared to healthy volunteers, but not patients with IPF. BALF CCL21 levels were negatively correlated with the forced expiratory volume in 1 s percentage and diffuse capacity of the lung for carbon monoxide (r=−0.662, p=0.007 and r=−0.671, p=0.024, respectively). According to the immunohistochemical analyses, CCL21 was expressed in the lymphatic endothelium in both conditions and CCR7+ cells were aggregated around lymphatics in patients with HP, but not in patients with IPF.Conclusions Lymphangiogenic factors might be associated with the inflammatory and functional severity of HP. The increased BALF VEGF-D levels were associated with lymphatic alveolitis intensity, and CCL21 with lung function impairment. ER -