Seminar"A novel fluorogenic chemical probe for live microglia visualization" by Dr. Fukuda

Title: A novel fluorogenic chemical probe for live microglia visualization

Speaker: Dr. Masahiro Fukuda

Date: Thursday, January 24 

Time: 14:00 - 15:00

Venue: D014, Lab1

Abstract: 

Microglia are central nervous system (CNS)-resident macrophages that regulate and maintain CNS homeostasis during development and in healthy and disease states. The observation of microglia is predominantly restricted to either histopathological techniques utilizing post-mortem CNS tissues or fluorescent imaging using knock-in or transgenic mouse lines that express fluorescent proteins in microglia lineages. Therefore, efforts have been dedicated to generating or identifying biomolecules orsmall chemical probes that target microglia population in situ and in vivo.

Through a thorough structure-activity relationships study, we developed a microglia-specific probe, CDr20, which can be applied both to in vitro and in vivo live imaging. CDr20 selectively stained cultured rodents’ microglia, cultured human microglia and microglia in the rodents’ brains. We confirmed that intravenously delivered CDr20 labeled cortical microglia if and only if the blood brain barrier was compromised using mild ischemia, systemic inflammation and Alzheimer’s disease model animals. The complete overlapping of CDr20-fluorescence positive population and microglia population was confirmed by FACS and single cell RNA seq. We investigated the mechanism of microglia specific staining by CDr20, and we found that a microglia specific enzyme through a genome-scale CRISPR-Cas9 screening. The novel mechanism of turning on CDr20 fluorescence only happens in microglia will be presented.