Fig. 1.

Primary cilia are expressed in human airway smooth muscle cells. Primary cilia (PC) were assessed in ASMCs in culture and in airway smooth muscle in human normal and asthmatic lung. A and B: normal ASMCs (Lonza) were grown to confluence on eight-well glass chamber slides and then serum starved overnight. PC were detected with antibodies to acetylated tubulin (green) and γ-tubulin (red; A) or with antibodies to Arl13b (green) and rootletin (red; B). Arrows point to PC. Scale bars = 20 μm (5 μm for insets). C–J: adjacent sections of formalin-fixed human asthmatic (C–F) or healthy (G–J) lung biopsies were stained with antibodies to either α-smooth muscle actin (red; C, E, G, and I) or Arl13b and rootletin (green and red, respectively; D, F, H, and J). Arrows point to PC, to show localization of PC to regions positive for α-smooth muscle actin staining. Nuclei for all images are marked by DAPI (blue). SM, smooth muscle cells; V, vessel; BE, bronchoepithelial cells.