Fig. 2

In vivo imaging of Cx3cr1–Dendra2 in healthy retina. A Retinal microglia in a Cx3cr1^D2/D2 retina from a female mouse appeared qualitatively normal in density and distribution using in vivo SLO under 488 nm excitation both before (unconverted) and immediately after (converted) exposure of a small retinal area to 405 nm light (75 µW, 365 × 365 µm area, 9 J/cm2 radiant exposure). The 405 nm exposure resulted in a clearly defined region of rD2 fluorescence; rD2 was not observed in surrounding regions or in the unconverted eye. Composite image shows a pseudo-colored merge of the 488 nm and 561 nm images; zoomed region denoted by dashed lines. Scale 300 µm; zoom scale 50 µm, n = 8 retinas (5 mice). B Changes in rD2 fluorescence over the course of 1 week taken from the same eye as shown in A. Converted region denoted with a white box; blood vessels drawn for reference. Scale 300 µm. C Quantification of rD2 using spectral analysis taken over 7 days (mean ± SEM, n = 5 retinas). Insets show zoomed images taken from the same mouse as in A at days 1–3 after photoconversion. Scale 50 µm