We will develop a novel microphysiological platform optimized for integrating 3D-bioprinted biomimetic scaffolds with in situ embedded pancreatic islets of Langerhans in vitro modeling of the endocrine pancreas. The approach combines 3D-bioprinted biomimetic scaffolds incubated under dynamic environmental conditions of a microphysiological system for the first time. The developed system will support optimal islet viability and functionality by providing the structural, mechanical, and biochemical requirements while ensuring physiologically relevant microenvironmental conditions and the continuous diffusion of nutrients, metabolites, and key soluble factors, leading to the formation of complex biochemical gradients required for their long-term endocrine function.