Fig. 1

Assessment of naphthalene-induced club cell injury. C57BL/6 J mice were intraperitoneally injected with naphthalene or corn oil on day −2 and intratracheally administered bleomycin or vehicle on day 0. a Immunohistochemistry for CCSP in lung tissues was performed on days 1, 7, and 14, and representative images for the control, naphthalene alone, bleomycin alone, and bleomycin following naphthalene samples are shown. b Semi-quantified data of the ratio of the CCSP-positive cells to the bronchiolar epithelium. Data are presented as the mean ± SE of three mice. *P < 0.01 compared with control, ^† P < 0.05 and ^‡ P < 0.01 compared between paired groups. N = naphthalene alone; B = bleomycin alone; N + B = bleomycin following naphthalene; CCSP = club cell secretory protein