Ab2182

Transplanted tissues were fixed with 4% paraformaldehyde. Paraffin embedded tissue sections were stained with haematoxylin/eosin. Then, the paraffin sections were deparaffinized with xylene and sequential 100%, 95%, 80%, 70% ethanol treatments for 5 min each. The sections were treated with 10 mM citric acid (pH 6) at 95°C for 50 min followed by permeation with 0.4% Triton-X in PBS at room temperature for 30 min. The deparaffinized sections were stained with antibodies against human Lamin-A (1∶200; ab108595; Abcam), BEST1 (1∶200; ab2182; Abcam) and Ki-67 (1∶400; #9449; Cell Signaling). Nuclei were stained with Hoechst 33258 (Dojindo) and DAPI (Dojindo). hiPSC-derived RPE cells were collected in suspension and fixed with 4% paraformaldehyde followed by staining with antibodies against POU5F1 (OCT3/4) (1∶ 100; sc-5279; Santa Cruz), or BEST1 (1∶ 200; ab2182; Abcam). Antibodies were visualized with Alexa Fluor 488 goat anti-mouse (1∶ 1,000; Invitrogen) or Alexa Flour 488 goat anti-rabbit (1∶ 1,000; Invitrogen). Fluorescent microscopic images were captured with a fluorescent microscope (Olympus BX51, IX71, Tokyo, Japan).

Cells were fixed in 4% formaldehyde (Sigma, 47608) for 15 min at room temperature and permeabilised with 0.25% Triton X-100 (Sigma, T8787) for 15 min, followed by treatment with blocking solution (3% BSA in PBS, Sigma, A3311) for 30 min at room temperature. Cells were treated with primary antibodies anti-bestrophin (Abcam, ab2182, 1:300), anti-sodium potassium ATPase (Alexa Fluor® 488 conjugate) (Abcam, ab197713, 1:50), pericentrin (Abcam, ab28144, 1:500), MERTK (Bethyl, A300-222A, 1:200), ARL13B (Proteintech, 17711-1-AP, 1:500), collagen IV (Abcam, ab6586, 1:200), PRPF31 (Abnova, PAB7154, 1:500) and SNRPB monoclonal antibody (Y12) (ThermoFisher, MA5-13449, 1:500), overnight at 4 °C, and with secondary antibodies anti-rabbit FITC (Sigma, T9887, 1:500) or anti-mouse FITC (Jackson Immuno Research, 715-095-151, 1:500) and anti-mouse Cy3 (Jackson Immuno Research, 115-165-003, 1:500) or anti-rabbit Cy3 (Jackson Immuno Research, 111-165-003, 1:500) diluted in PBS for 1 h at room temperature. Washes with PBS were carried out between and after treatments. Finally, cells were treated with the nuclear stain-DAPI (Partec, 05-5005), and imaged using a Nikon A1R confocal microscope in combination with the associated NIS Elements software. All antibody details are shown in Supplementary Data 6.