It has even been possible to study organism‐level, hormonal cross‐talk, such as between insulin production in pancreas and glucose regulation in liver by fluidically coupling two microfluidic chips lined by human pancreatic islet microtissues and liver spheroids.[58] A functional hormonal feedback loop between the human liver and insulin‐secreting islet tissues was demonstrated in this study, which suggests that it might be useful for studying diabetes in humans. This evidence concerns the gene INS and diabetes mellitus.