By suppressing the loss of living cells or living tissue during the production of a PVA gel that contains living cells or living tissue, the present invention addresses the problem of supplying a cell- or tissue-embedding device that has a high capacity for supplying a biologically active substance. According to the present invention, an aqueous gel for forming an immunoisolation layer for a cell- or tissue-embedding device is formed from a polyvinyl alcohol resin that has a triad syndiotacticity of 32%-40%.本發明之課題在於：於製作含有活細胞或活體組織之PVA凝膠之製程中，藉由抑制活細胞或活體組織之減少，而供給生理活性物質之供給能力較高之細胞或組織包埋裝置。 本發明將間規性以三元組表示而為32～40%之聚乙烯醇樹脂作為成分而構成用以形成細胞或組織包埋裝置之免疫隔離層的水性凝膠。
