FOXP3 expression on sarcoid infiltrating T-cells. A Cryostat sections of sarcoid tissue stained with rabbit anti-FOXP3 (ab 10563) and donkey anti rabbit texas-red with blue DAPI nuclear counterstain. B Same section stained using both mouse monoclonal anti-CD4 and monoclonal anti-CD8α with goat anti mouse FITC conjugate. C Combined image showing CD4 and CD8 stained T-cells and non T-cells all express FOXP3. D Specificity control slide stained with normal rabbit immunoglobulin and isotype matched control mouse monoclonal antibody, DAPI counterstain. E Cryostat sections of sarcoid tissue stained with rat anti-FOXP3 (FJK-16s) and donkey anti rat FITC with blue DAPI nuclear counterstain. F Same section stained using mouse anti equine CD4 with goat anti mouse TRITC conjugate. G Combined image showing both CD4 stained T-cells and non T-cells express FOXP3. H Combined image at higher power with CD4-negative FOXP3 positive cells highlighted (arrow).