Fig. 3: TGM2 staining in necrotic regions of the xenograft.

A Necrotic region showing palisading (region under red bracket). Abundant apoptotic cells are present within the necrotic region and between the palisading cells (small dark blue nuclei, examples indicated with red arrowheads). Strongly TGM2 positive cells are present within the necrotic region; B Necrotic region with few apoptotic cells. Strongly TGM2-positive cells are predominantly localized around the edges of the necrotic region. For A and B, red arrows indicate TGM2-positive cells showing apparent efferocytosis of apoptotic cells; C Examples of TGM2-positive cells engaged in efferocytosis within necrotic regions. Left panel shows closeup of the cell indicated by a red arrow in A, right panel shows an example taken from outside the area shown in A. For both panels the outline of macrophages (with some adjacent/associated apoptotic cells) is shown with a thin red line. The red arrows indicate apoptotic cells that are likely being engulfed by the macrophages; D Examples of TGM2-positive cells engaged in efferocytosis at the edges of necrotic regions. Close-ups are of cells indicated with red arrows in B; E Region of necrosis in mouse xenograft model with immunohistochemistry for cleaved caspase 3. Multiple cleaved caspase 3-positive apoptotic cells are present within and around the border of the necrotic region; F Smaller regions of necrosis showing cleaved caspase 3-positive apoptotic cells; G Cleaved caspase 3-positive apoptotic cells clustered around a normal cell nucleus, consistent with macrophage efferocytosis (closeup of a cell marked with a red arrow in F).