Fig. 4

In vitro autoradiography of [¹¹C]AZ12204657 reveals focal binding patterns on pancreatic sections from non-diabetic human donors (a). The binding could be competed away with an excess of GPR44 antagonist AZD3825 (b). Similar GPR44-mediated binding was seen in pancreatic sections from T2D donors (c, d). The focal binding corresponded to Islets of Langerhans as assessed by immunofluorescent insulin staining (e, f) (representative results from three independent experiments on human sections with measurements performed in duplicates). The islet specific targeting was further assessed by [¹¹C]AZ12204657 binding to homogenates of purified human islets of Langerhans and exocrine tissue preparations (results are from two independent experiments on homogenates with measurements performed in triplicates) (g). Binding of [¹¹C]AZ12204657 in pancreatic sections from NHP was similarly focal in nature (h), consistent with the heterogeneous distribution of islets of Langerhans (i), and GPR44-mediated (j) (representative results from six independent experiments on NHP sections with measurements performed in singlets or duplicates)