title: Multiphoton fluorescence lifetime imaging of 3D-stem cell spheroids during differentiation.
abstract: Long-term high-resolution multiphoton imaging of nonlabeled human salivary gland stem cell spheroids has been performed with submicron spatial resolution, 10.5-nm spectral resolution, and picosecond temporal resolution. In particular, the two-photon-excited coenzyme NAD(P)H and flavins have been detected by time-correlated single photon counting (TCSPC). Stem cells increased their autofluorescence lifetimes and decreased their total fluorescence intensity during the adipogenic-differentiation process. In addition, the onset of the biosynthesis of lipid vacuoles was monitored over a period of several weeks in stem-cell spheroids. Time-resolved multiphoton autofluorescence imaging microscopes may become a promising tool for marker-free stem-cell characterization and cell sorting.
authors.affiliation: Saarland University, Department of Biophotonics and Laser Technology, Faculty of Mechatronics and Physics, 66123 Saarbrücken, Germany. k.koenig@blt.uni-saarland.de
authors.forename: Karsten
authors.initials: K
authors.lastname: König
authors.forename: Aisada
authors.initials: A
authors.lastname: Uchugonova
authors.forename: Erwin
authors.initials: E
authors.lastname: Gorjup
mesh_terms: D002454:Cell Differentiation; D002478:Cells, Cultured; D005453:Fluorescence; D006801:Humans; D050356:Lipid Metabolism; D036641:Microscopy, Fluorescence, Multiphoton / Q000379:methods*; D012469:Salivary Glands / Q000737:chemistry / Q000166:cytology / Q000378:metabolism; D013234:Stem Cells / Q000737:chemistry* / Q000166:cytology* / Q000378:metabolism