Inactivation of Tat protected against Tat-induced RPE apoptosis.

<p>An anti-Tat antibody was added to the ARPE-19 and incubated for 24 hours, and the cells were then incubated with or without 200 ng/ml Tat for 48 hours. Representative flow cytometry images showing the percentage of cells in early apoptosis using Annexin V-FITC staining (<b>A</b>). Immunofluorescence micrographs showing apoptosis using Annexin V-FITC staining (green) with nuclei counterstained with PI (red). Scale bar: 50 µm (<b>B</b>). Both of these analyses showed that the Tat antibody protected ARPE-19 cells from the apoptosis induced by Tat. After incubation with the Tat antibody for 24 h, the ARPE-19 cells were cultured with Tat for 0, 6, 24 or 48 h. The expression levels of NMDAR, Bax, Bak and Cytochrome c were quantitatively analyzed using qPCR (*, P<0.05 vs. control) (<b>C</b>) (<b>D</b>) and Western blotting (<b>E</b>). The corresponding graphs show the quantification of 3 independent experiments performed in duplicate; the data were normalized to cells without Tat treatment (<b>#</b>, P<0.05 vs. control) (<b>F</b>).