The gut microbiota can promote chronic inflammatory intestinal diseases that result in excessive bone resorption and osteoporosis, leading to a high risk of fractures. The project aims to model this gut/bone axis by coupling two physiologically relevant NAMs: a dysbiosis-enabled gut organoid model as well as a 3D bone model with remodelling capability. Building on established protocols to produce human physiologically relevant intestinal epithelium on Transwell filter inserts, the gut model is integrated into a chip with anaerobic microbiota under inflammatory and non-inflammatory conditions. The 3D bone model is established by co-culturing human mesenchymal stem cells, endothelial cells and blood monocytes on calcium phosphate particles combined with a human based extracellular matrix to form reproducible vascularized 3D bone constructs. These bone constructs will be generated from pooled donors to minimize variability due to both gender and age differences for relevant human physiology modelling. The 3D bone constructs will be integrated into a multi-channel perfusion microfluidic chip with on-line measurements of bone formation and resorption biomarkers. Both microbiota/gut and bone will be combined for modelling in vitro and in silico human pathophysiology, as well as the response to drug treatments against inflammatory intestinal and osteoporotic diseases. Generated data will be compared to clinical data of osteoporotic patients. Surface plasmon resonance biosensors will be integrated to monitor the secretome of both intestinal and bone models, and relevant gases. By engaging in validation efforts and interacting with EMA and ECVAM along the process, the project will deliver a fully human, xeno free, multi organ model. This project will generate novel mechanistic insights into the pathogenesis of gut-driven bone loss and accelerate the preclinical assessment of next-generation anti-inflammatory and bone-protective drugs.