Ultrastructural comparison by TEM.

<p>The TEM images show (A) a small cluster (3 cells) of Calu-3 cells grown in static suspension, and (B) a larger spheroid (9 cells) of Calu-3 cells cultured within the bioreactor, harvested both after 5 days of suspension culture. Prominent nucleoli (N: nuclei), cytoplasmic structures and longitudinally and transversally oriented microvilli are characteristic features of NSCLC cell line Calu-3. High magnification views of areas included in black rectangles in panels A and B shown, respectively, (A1) a single tiny adherence junction (arrowhead) among cells cultured under static suspension, and (B1) several well-developed adherence junctions (arrowheads) developed by Calu-3 cultured within the bioreactor. Scale bars: A and B = 5 μm; A1 and B1 = 1 μm.