CD68 and polyp: Both the polyp and the colonic biopsies showed evidence of pTDP‐43 aggregation within the lamina propria (the mucosal connective tissue deep to the surface enterocytes; Figure 2A) with examples of pTDP‐43 aggregates in CD68‐positive (i.e. activated) macrophages (Figure 2B) and in non‐CD68‐positive dendritic cells (Figure 2C).