Figure 5 of Hambright, Mol Vis 2012; 18:920-936.

Figure 5. Microglia accumulation in a subretinal graft with damaged retinal pigment epithelium/choroid. This is a typical staining pattern (A, B) observed in grafts where a needle penetrated retinal pigment epithelium (RPE) and disrupted choroid (Chr) vasculature (solid white arrows in B), leading to the rupture of the retinal–blood barrier and exposure of xenogenic (human) graft to the host’s immune system. By 3 weeks after subretinal transplantation, there are typically no surviving human neurons in such grafts, yet some human nuclei-positive immunoreactivity occasionally may be found. Solid white arrowheads point to the accumulation of ionized calcium binding adaptor molecule 1 (Iba-1) staining where the grafted cells were placed. The area of the main image displayed in the inset in panel B is indicated with an asterisk (*). The inset shows several Iba-1-positive cells with a morphology typical for activated microglia. The scale bar used in panel B is 50 μm. Double asterisk (**) in panel B indicates the area, enlarged in panels C and D. This is the host photoreceptor layer with high microglial activity, where human retinal progenitors were earlier grafted but did not survive. Microglial processes are shown with double white arrowheads. The following abbreviations were used in these panels: ONL – outer nuclear layer, INL, inner nuclear layer, RGC- retinal ganglion cells, DAPI – 4', 6-diamidino-2-phenylindole.