TnTs facilitate intercellular transfer of lipophilic cytosolic components as well as proteins, mitochondria, and golgi vesicles between MSTO-211H cells.

<p>a) Electron micrograph of two MSTO-211H cells connected via a TnT. b) Closer view of EM, illustrating that the TnT has more than one insertion point into the membrane of the MSTO cell. c) Cells stained with either green (DiO) or red (DiI) dyes formed TnTs which transmitted lipophilic components when mixed. d) and e) Cells expressing GFP or RFP formed TnTs which readily transmitted these proteins between cells, as demonstrated by time-lapse imaging. f) Fixed cells stained with Hoechst dye, GM130 (for Golgi vesicles), and MitoTracker demonstrated transfer of Golgi and mitochondria as well. g) TnTs relay significant amounts of mitochondria between cells. h) LP9 (normal mesothelial cells) can be induced to form TnTs in a low-serum, hyperglycemic microenvironment. i) Normal mesothelial cells also demonstrate an independent capability of TnT formation among themselves, but do not initiate or form connections to malignant mesothelioma cells via TnTs. LP9 cells stained with DiI (red) were mixed with MSTO-211H cells stained with DiO (green); normal mesothelial cells did not form TnT connections to malignant mesothelioma cells. Scale bars: a) 5 µm, b) 2 µm, c) 30 µm, d) 50 µm, e) 50 µm, f) 10 µm, g) 10 µm, h) 30 µm.