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UID:1-490@lptms.universite-paris-saclay.fr
DTSTART:20170517T110000Z
DTEND:20170517T120000Z
DTSTAMP:20170509T174849Z
URL:http://www.lptms.universite-paris-saclay.fr/seminars/physics-biology-i
 nterface-seminar-julien-husson/
SUMMARY:Physics-Biology interface seminar: Julien Husson - LPTMS\, salle 20
 1\, 2ème étage\, Bât 100\, Campus d'Orsay - 17 Mai 17 11:00
DESCRIPTION:Single-cell leukocyte mechanics: force generation\, viscoelasti
 city\, and rupture mechanics\nJulien Husson (LadHyX\, École polytechnique
 \, France)\nLeukocytes are very soft cells that perform many diverse funct
 ions: they adhere\, crawl\, transmigrate\, kill\, phagocytose or interact 
 with other cells. During their activation\, leukocytes both generate mecha
 nical forces and change their viscoelastic properties (i.e. they stiffen/s
 often\, get more or less viscous). We have developed micropipette-based se
 tups to quantify single-leukocyte mechanical properties and monitor them o
 ver time while a leukocytes gets activated by a relevant stimulus. We furt
 her quantify rupture properties of cell membrane\, as these help us to bet
 ter understand cell structure and dynamics.\n\nWe use this approach in div
 erse contexts involving leukocytes: activation of T lymphocytes\, phagocyt
 osis of a target by a neutrophil\, or transmigration of a lymphoblast acro
 ss an endothelial monolayer. We perform microrheology experiments with a p
 rofile microindentation setup [1\,2]\, measure forces generated by T lymph
 ocytes [3\,4]\, characterize cell-substrate adhesion [5] or establish a ru
 pture criteria for membrane rupture [2\,6] (Figure 1). These mechanical me
 asurements shed a new light on how cell mechanical properties evolve over 
 a short period of time (seconds)\, how they adapt to the stiffness of thei
 r environment\, and how intracellular signaling is involved.\n\n\nT-lympho
 cytes in the human body routinely undergo large deformations\, both passiv
 ely when going through narrow capillaries and actively when transmigrating
  across endothelial cells or squeezing through tissue. In this artistic re
 ndering\, a T-lymphocyte is aspirated in a micropipette to mimic passive d
 eformations that occur when squeezing through narrow capillaries. The fluo
 rescent signal is due to the entry of propidium iodide into the cell and i
 ndicates membrane rupture (Image: Julien Husson\, LadHyX\, Ecole polytechn
 ique\, cellmechanics.jimdo.com/galleries)\n\n\n1. Guillou\, L.\, Babataher
 i\, A.\, Puech\, P.-H.\, Barakat\, A.I. &amp\; Husson\, J. Dynamic monitor
 ing of cell mechanical properties using profile microindentation. Scientif
 ic Reports 6:21529 (2016).\n\n2. Guillou\, L.\, Babataheri\, A.\, Saitakis
 \, M.\, Bohineust\, A.\, Dogniaux\, S.\, Hivroz\, C.\, Barakat\, A.I. &amp
 \; Husson\, J. T lymphocyte passive deformation is controlled by unfolding
  of membrane surface reservoirs. Molecular Biology of the Cell 27(22): 357
 4-3582. (2016\, journal cover).\n\n3. Husson\, J.\, Chemin\, K.\, Bohineus
 t\, A.\, Hivroz\, C. &amp\; Henry\, N. Force Generation upon T Cell Recept
 or Engagement. PLoS One 6(5):e19680 (2011).\n\n4. Basu\, R.*\, Whitlock\, 
 B.M.*\, Husson\, J.*\, Le Floc’h\, A.\, Jin\, W.\, Dotiwala\, F.\, Giann
 one\, G.\, Hivroz\, C.\, Lieberman\, J.\, Kam\, L.C. &amp\; Huse\, M. Cyto
 toxic T Cells Use Mechanical Force to Potentiate Target Cell Killing. Cell
  165(1):100–110 (2016).\n\n5. Hogan\, B.\, Babataheri\, A.\, Hwang\, Y.\
 , Barakat\, A.I. &amp\; Husson\, J. Characterizing Cell Adhesion by Using 
 Micropipette Aspiration. Biophysical Journal 109(2):209-19 (2015).\n\n6. G
 onzalez-Rodriguez\, D.\, L. Guillou\, F. Cornat\, J. Lafaurie-Janvore\, A.
  Babataheri\, E. de Langre\, A.I. Barakat\, and J. Husson. Mechanical Crit
 erion for the Rupture of a Cell Membrane under Compression. Biophys. J. 11
 1: 2711–2721 (2016).
CATEGORIES:physbio,seminars
LOCATION:LPTMS\, salle 201\, 2ème étage\, Bât 100\, Campus d'Orsay\, 15 
 Rue Georges Clemenceau\, Orsay\, 91405\, France
GEO:48.698185;2.181768
X-APPLE-STRUCTURED-LOCATION;VALUE=URI;X-ADDRESS=15 Rue Georges Clemenceau\,
  Orsay\, 91405\, France;X-APPLE-RADIUS=100;X-TITLE=LPTMS\, salle 201\, 2è
 me étage\, Bât 100\, Campus d'Orsay:geo:48.698185,2.181768
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