1 research outputs found
Label-Free Metabolic Imaging In Vivo by Two-Photon Fluorescence Lifetime Endomicroscopy
NADH
intensity and fluorescence lifetime characteristics have proved
valuable intrinsic biomarkers for profiling the cellular metabolic
status of living biological tissues. To fully leverage the potential
of NADH fluorescence lifetime imaging microscopy (FLIM) in (pre)clinical
studies and translational applications, a compact and flexible endomicroscopic
embodiment is essential. Herein we present our newly developed two-photon
fluorescence (2PF) lifetime imaging endomicroscope (2p-FLeM) that
features an about 2 mm diameter, subcellular resolution, and excellent
emission photon utilization efficiency and can extract NADH lifetime
parameters of living tissues and organs reliably using a safe excitation
power (∼30 mW) and moderate pixel dwelling time (≤10
μs). In vivo experiments showed that the 2p-FLeM system was
capable of tracking NADH lifetime dynamics of cultured cancer cells
and subcutaneous mouse tumor models subject to induced apoptosis,
and of a functioning mouse kidney undergoing acute ischemia–reperfusion
perturbation. The complementary structural and metabolic information
afforded by the 2p-FLeM system promises functional histological imaging
of label-free internal organs in vivo and in situ for practical clinical
diagnosis and therapeutics applications