title: Fabrication and operation of GRIN probes for in vivo fluorescence cellular imaging of internal organs in small animals.
abstract: Intravital fluorescence microscopy has emerged as a powerful technique to visualize cellular processes in vivo. However, owing to their size, the objective lenses required have limited physical accessibility to various tissue sites in the internal organs of small animals. The use of small-diameter probes using graded-index (GRIN) lenses expands the capabilities of conventional intravital microscopes to minimally invasive imaging of internal organs. In this protocol, we describe the detailed steps for the fabrication of front- and side-view GRIN probes and the integration and operation of the probes in a confocal microscope to enable visualization of fluorescent cells and microvasculature in various mouse organs. Some experience in building an optical setup is required to complete the protocol. We also present longitudinal imaging of immune cells in renal allografts and tumor development in the colon. Fabrication and integration can be completed in 5-7 h, and a typical in vivo imaging session takes 1-2 h.
authors: Harvard Medical School and Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts, USA.
authors: Jun Ki
authors: JK
authors: Kim
authors: Woei Ming
authors: WM
authors: Lee
authors: Pilhan
authors: P
authors: Kim
authors: Myunghwan
authors: M
authors: Choi
authors: Keehoon
authors: K
authors: Jung
authors: Seonghoon
authors: S
authors: Kim
authors: Seok Hyun
authors: SH
authors: Yun
mesh_terms: D000818:Animals; D003110:Colonic Neoplasms / Q000175:diagnosis; D004867:Equipment Design; D016030:Kidney Transplantation; D007909:Lenses; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D018613:Microscopy, Confocal / Q000295:instrumentation; D008856:Microscopy, Fluorescence / Q000295:instrumentation* / Q000379:methods*; D051598:Whole Body Imaging / Q000379:methods