Mechanisms of Activation and Serotonin release from Human Enterochromaffin Cells

Gastrointestinal (GI) enterochromaffin (EC) cells are specialised sensors of luminal stimuli. They secrete most of the body's serotonin (5-HT), and are critical for modulating GI motility, secretion, and sensation, while also signalling satiety and intestinal discomfort. The aim of this study was to investigate mechanisms underlying the regulation of human EC cells, and the relative importance of direct nutrient stimulation compared with neuronal and paracrine regulation. Overall design: Intestinal organoids from human duodenal biopsies were modified using CRISPR-Cas9 to specifically label EC cells with the fluorescent protein Venus. EC cells were purified by fluorescence-activated cell sorting for analysis by bulk RNA sequencing.