A peptide-based near-infrared fluorescence probe for dynamic monitoring senile plaques in Alzheimer’s disease mouse model

In vivo monitoring neuropathological changes in Alzheimer's disease (AD) animal model is critical for drug development. Here, by integrating blood-brain barrier penetrable peptide, we have developed a peptide probe which based on angiopep-2. Angiopep-based probe exhibited high binding affinity to Aβ aggregates and labeled senile plaques in vivo. Remarkably, the in vivo near-infrared imaging data revealed that fluorescence signals of this probe were nearly 3-fold higher in the brains of 16-month-old APP/PS1 transgenic mice compared to C57 mice and exhibited linear correlation with the senile plaques load process in 4-, 8-, 16-month-old APP/PS1 transgenic mice. Moreover, senile plaques load was detected in vivo as early as 4 months of age that even at the very beginning of plaques developed in APP/PS1 transgenic mice. Taken together, this novel peptide-based probe achieved dynamic monitoring senile plaques in APP/PS1 transgenic mice and have been ready to use in drug development in AD mouse model.