HIF1A and Granuloma: Confocal microscopy images show nuclei stained with DAPI (blue) in a single AM (C) and a multinucleated giant cell (D), nuclear and cytoplasmic accumulation of HIF-1α in green (E and F), overlay image shows nuclear co-localization of HIF-1α (G and H).We saw enhanced expression and accumulation of HIF-1α in the cytoplasm and nuclei of sarcoidosis AMs, both in a single AM (Figure 3E) and in a multinucleated giant cell (Figure 3F) that are known to be characteristic cells in sarcoidosis granuloma.