Sarcoid MHC expression. Frozen sarcoid tissue stained with (A) Mouse monoclonal anti-equine MHC II. Goat anti-mouse FITC. B Rabbit anti CD3 donkey anti-rabbit Texas red (C) combined image with DAPI counterstain, the majority of MHC II expressing cells are CD3+ T-cells. D Mouse monoclonal anti-equine MHC I. Goat anti-mouse FITC. E Rabbit anti CD3 donkey anti-rabbit Texas red (F) combined image with DAPI counterstain the strongly MHC I positive cells are CD3+ T-cells. G Monoclonal anti-BPV E2 goat anti-mouse IgG1 FITC, (H) Monoclonal anti-equine MHC I goat anti mouse IgG2a. I Combined image with some possible E2 MHC I dual positive cells (arrow).