  Retinal degenerative diseases lead to the blindness of millions of people
around the world. In case of age-related macular degeneration (AMD), the
atrophy of retinal pigment epithelium (RPE) precedes neural dystrophy. But as
crucial as understanding both healthy and pathological RPE cell physiology is
for those diseases, no current technique allows subcellular in vivo or in vitro
live observation of this critical cell layer. To fill this gap, we propose
dynamic full-field OCT (D-FFOCT) as a candidate for live observation of in
vitro RPE phenotype. In this way, we monitored primary porcine and human stem
cell-derived RPE cells in stress model conditions by performing scratch assays.
In this study, we quantified wound healing parameters on the stressed RPE, and
observed different cell phenotypes, displayed by the D-FFOCT signal. In order
to decipher the subcellular contributions to these dynamic profiles, we
performed immunohistochemistry to identify which organelles generate the signal
and found mitochondria to be the main contributor to D-FFOCT contrast.
Altogether, D-FFOCT appears to be an innovative method to follow degenerative
disease evolution and could be an appreciated method in the future for live
patient diagnostics and to direct treatment choice.
