Imaging Macrophage Phagocytosis Using AIE Luminogen-Labeled E. coli

Phagocytosis of bacteria is an important biological process. Gaining insight into this process may greatly benefit related pathological studies and further contribute to development of therapies for infectious diseases. Tools for studying these internalization processes, however, are limited. Herein, we demonstrate the feasibility of employing an environmentally sensitive aggregation-induced emission (AIE) probe for bacteria labeling and imaging. By tracking the fluorescence variation of the stained bacteria, the pH changes of its microenvironment can be monitored. In this way, the phagocytic entry of these bacteria into the macrophage cells and the intravacuolar acidification can be visualized in real-time.