Abstract: According to embodiments, a method of producing insulin-producing tissues (IPTs) by culturing comprises: preparing non-endocrinal epithelial cells (NEECs) and vascular endothelial cells (VECs), which have been isolated or originated from postnatal pancreata, preferably by capturing of NEECs by collagen; culturing in vitro the NEECs and the VECs at least partly separately from each other; and then generating in vitro a tissue complex (IPTs) that contains both the NEECs and the VECs. In another embodiment, the native islet cells are seeded on a monolayer of VECs that have preferably been separately cultured and purified. In a further embodiment, a method of enriching NEECs comprises: culturing NEECs adhering to a container or substrate; removing NEECs by treating with a tissue-dissociation enzyme to leave left-over cells (LOCs) still attached on the container or substrate; and culturing NEECs in a medium conditioned by, or in the presence of the LOCs.

Abstract: According to embodiments, a method of producing insulin-producing tissues (IPTs) by culturing comprises: preparing non-endocrinal epithelial cells (NEECs) and vascular endothelial cells (VECs), which have been isolated or originated from postnatal pancreata, preferably by capturing of NEECs by collagen; culturing in vitro the NEECs and the VECs at least partly separately from each other; and then generating in vitro a tissue complex (IPTs) that contains both the NEECs and the VECs. In another embodiment, the native islet cells are seeded on a monolayer of VECs that have preferably been separately cultured and purified. In a further embodiment, a method of enriching NEECs comprises: culturing NEECs adhering to a container or substrate; removing NEECs by treating with a tissue-dissociation enzyme to leave left-over cells (LOCs) still attached on the container or substrate; and culturing NEECs in a medium conditioned by, or in the presence of the LOCs.