ja5b00042_si_001.pdf (2.11 MB)
Development of Targetable Two-Photon Fluorescent Probes to Image Hypochlorous Acid in Mitochondria and Lysosome in Live Cell and Inflamed Mouse Model
journal contribution
posted on 2015-05-13, 00:00 authored by Lin Yuan, Lu Wang, Bikram Keshari Agrawalla, Sung-Jin Park, Hai Zhu, Balasubramaniam Sivaraman, Juanjuan Peng, Qing-Hua Xu, Young-Tae ChangHypochlorous acid
(HOCl), as a highly potent oxidant, is well-known
as a key “killer” for pathogens in the innate immune
system. Recently, mounting evidence indicates that intracellular HOCl
plays additional important roles in regulating inflammation and cellular
apoptosis. However, the organelle(s) involved in the distribution
of HOCl remain unknown, causing difficulty to fully exploit its biological
functions in cellular signaling pathways and various diseases. One
of the main reasons lies in the lack of effective chemical tools to
directly detect HOCl at subcellular levels due to low concentration,
strong oxidization, and short lifetime of HOCl. Herein, the first
two-photon fluorescent HOCl probe (TP-HOCl 1) and its mitochondria-
(MITO-TP) and lysosome- (LYSO-TP) targetable derivatives for imaging
mitochondrial and lysosomal HOCl were reported. These probes exhibit
fast response (within seconds), good selectivity, and high sensitivity
(<20 nM) toward HOCl. In live cell experiments, both probes MITO-TP
and LYSO-TP were successfully applied to detect intracellular HOCl
in corresponding organelles. In particular, the two-photon imaging
of MITO-TP and LYSO-TP in murine model shows that higher amount of
HOCl can be detected in both lysosome and mitochondria of macrophage
cells during inflammation condition. Thus, these probes could not
only help clarify the distribution of subcellular HOCl, but also serve
as excellent tools to exploit and elucidate functions of HOCl at subcellular
levels.