Fig. 2
From: Homogentisic acid-derived pigment as a biocompatible label for optoacoustic imaging of macrophages
Microscopic confirmation of intracellular HDP formation in primary macrophages after HGA treatment. a Intracellular co-localization of HDP-laden vesicles, as seen in bright field, with late endosomes/lysosomes verified by immunofluorescence staining with anti-Lamp1 antibody (Alexa 488, orange). Arrows indicate single pigmented vesicles and aggregates thereof (top arrow pointing at aggregate). Cell nuclei are stained with Dapi. Scale bar is 5 µm. b Live cell optoacoustic signal acquisition of HDP allowing intensity quantification of single vesicles surrounding the cell nucleus indicated by N (top, pixel size is 0.2 µm, scale bar of 2 µm). HDP vesicles are visualized by blue coloration after Schmorl’s staining of cells (bottom, scale bar is 20 µm). +HGA cells were treated with 0.5 mM HGA for 96 h
