title: Two-photon imaging of lymphocyte motility and antigen response in intact lymph node.
abstract: Lymphocyte motility is vital for trafficking within lymphoid organs and for initiating contact with antigen-presenting cells. Visualization of these processes has previously been limited to in vitro systems. We describe the use of two-photon laser microscopy to image the dynamic behavior of individual living lymphocytes deep within intact lymph nodes. In their native environment, T cells achieved peak velocities of more than 25 micrometers per minute, displaying a motility coefficient that is five to six times that of B cells. Antigenic challenge changed T cell trajectories from random walks to "swarms" and stable clusters. Real-time two-photon imaging reveals lymphocyte behaviors that are fundamental to the initiation of the immune response.
authors.affiliation: Department of Physiology and Biophysics, University of California, Irvine, CA 92697-4561, USA.
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Miller
authors.forename: Sindy H
authors.initials: SH
authors.lastname: Wei
authors.forename: Ian
authors.initials: I
authors.lastname: Parker
authors.forename: Michael D
authors.initials: MD
authors.lastname: Cahalan
mesh_terms: D019264:Adoptive Transfer; D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology / Q000502:physiology; D000941:Antigens / Q000276:immunology*; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology / Q000502:physiology; D002455:Cell Division; D002465:Cell Movement; D048429:Cell Size; D005452:Fluoresceins; D005456:Fluorescent Dyes; D007091:Image Processing, Computer-Assisted; D007834:Lasers; D008198:Lymph Nodes / Q000166:cytology / Q000276:immunology*; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D008853:Microscopy / Q000379:methods; D009040:Motion Pictures; D017785:Photons; D012235:Rhodamines; D013388:Succinimides; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology / Q000502:physiology*; D013696:Temperature
chemical_list: C116572:(((4-chloromethyl)benzoyl)amino)-tetramethylrhodamine; C087165:5-(6)-carboxyfluorescein diacetate succinimidyl ester; D000941:Antigens; D005452:Fluoresceins; D005456:Fluorescent Dyes; D012235:Rhodamines; D013388:Succinimides