A delayed type of three-dimensional growth of human endothelial cells under simulated weightlessness.
Endothelial cells (ECs) form three-dimensional (3D) aggregates without any scaffold when they are exposed to microgravity simulated by a random positioning machine (RPM) but not under static conditions at gravity. Here we describe a delayed type of formation of 3D structures of ECs that was initiated when ECs cultured on a desktop RPM remained adherent for the first 5 days but spread over neighboring adherent cells, forming little colonies. After 2 weeks, tube-like structures (TSs) became visible in these cultures. They included a lumen, and they elongated during another 2 weeks of culturing. The walls of these TSs consisted mainly of single-layered ECs, which had produced significantly more beta(1)-integrin, laminin, fibronectin, and alpha-tubulin than ECs simultaneously grown adhering to the culture dishes under microgravity or normal gravity. The amount of actin protein was similar in ECs incorporated in TSs and in ECs growing at gravity. The ratio of tissue inhibitor of metalloproteinases-1 to matrix metalloproteinase-2 found in the supernatants was lower at the seventh than at the 28th day of culturing. These results suggest that culturing ECs under conditions of modeled gravitational unloading represents a new technique for studying the formation of tubes that resemble vascular intimas.
Grimm
Daniela
D
Institute of Clinical Pharmacology and Toxicology, CBF/CCM, Charité-Universitätsmedizin , Berlin, Berlin, Germany. daniela.grimm@farm.au.dk
Infanger
Manfred
M
Westphal
Kriss
K
Ulbrich
Claudia
C
Pietsch
Jessica
J
Kossmehl
Peter
P
Vadrucci
Sonia
S
Baatout
Sarah
S
Flick
Burkhard
B
Paul
Martin
M
Bauer
Johann
J
D000199:Actins / Q000378:metabolism; D015153:Blotting, Western; D002460:Cell Line; D049109:Cell Proliferation; D003470:Culture Media; D003599:Cytoskeleton / Q000378:metabolism / Q000648:ultrastructure; D042783:Endothelial Cells / Q000166:cytology* / Q000201:enzymology / Q000648:ultrastructure; D005109:Extracellular Matrix / Q000378:metabolism / Q000648:ultrastructure; D016326:Extracellular Matrix Proteins / Q000378:metabolism; D006801:Humans; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism; D018919:Neovascularization, Physiologic; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000378:metabolism; D014404:Tubulin / Q000378:metabolism; D014893:Weightlessness; D018474:Weightlessness Simulation
D000199:Actins; D003470:Culture Media; D016326:Extracellular Matrix Proteins; D019715:Tissue Inhibitor of Metalloproteinase-1; D014404:Tubulin; D020778:Matrix Metalloproteinase 2