Multiphoton microscopy for blood vessel imaging: new non-invasive tools (Spectral, SHG, FLIM)
Issue title: Selected Papers from 1st Meeting on “Cardiovascular Biology: Endothelial Cell in Health and Hypertension”, 30 June–1 July 2006, Prague, Czech Republic
Affiliations: LEMTA CNRS UMR 7563 et IFR CNRS 111-Bioingéniérie, Nancy Université, Faculté de Médecine Nancy Groupe de Mécanique et Ingénierie Cellulaire et Tissulaire, 54 505 Vandoeuvre-lès-Nancy, France
Note: [] Corresponding author: E. Werkmeister, Laboratoire de Mécanique et Ingénierie Cellulaire et Tissulaire, Faculté de Médecine, Université Henri Poincaré Nancy 1, 54505 Vandoeuvre-lès-Nancy, France. Tel.: +33 3 83 68 34 58; Fax: +33 3 83 68 34 59; E-mail: elisabeth.werkmeister@medecine.uhp-nancy.fr.
Abstract: Imaging thick and opaque tissue, like blood vessel, in a noninvasive mode with high resolution, is nowadays possible with multiphoton technology. A near-infrared excitation presents the advantage to be compatible with living specimens and allows a deep penetration into tissues. The nonlinear excitation process is followed by several deactivation ways, among which fluorescence emission can be represented with Spectral or Lifetime imaging. Applied to ex vivo blood vessel imaging, these techniques enabled us to discriminate cell structures (nucleus, cytoskeleton) by fluorescent labelling (Hoechst, QDots). Another method, based on 2-photon excitation and which doesn't need any exogenous dye has also been experimented on arteries: SHG (Second Harmonic Generation) is a diffusion process generated from organized structures. Collagen molecules give rise to a strong SHG signal, enabling us to image the arterial wall (3-dimensional extracellular matrix).
Keywords: Spectral imaging, fluorescence lifetime imaging microscopy, second harmonic generation
