Margo Tuerlings | 27-09-2023 | The bone and cartilage interplay in osteoarthritis: key to effective treatment strategy.
Osteoarthritis (OA) is a prevalent age-related joint disease, determined by diverse changes in pathways maintaining articular cartilage and subchondral bone. This thesis aimed to identify and study gene networks driving interacting etiopathophysiological OA processes in cartilage and subchondral bone. Hereto, characterization of the molecular landscape of bone and cartilage of OA patients showed 305 genes with similar direction of effect, including IL11 and CHADL. Moreover, to capture biological complexity and decipher underlying OA disease mechanisms a variety of human 3D cartilage and bone organoids models were exploited and a human osteochondral construct-on-a-chip was developed. Herein, we showed that the robust OA risk gene WWP2 may initiate OA, via aberrant responses in hypoxia-associated genes and a decrease in anabolic markers. Additionally we showed, as reflected by upregulation of SPP1 and downregulation of WNT16 in cartilage, that treatment of ex vivo human osteochondral explants with human recombinant IL11 does not necessarily has a beneficial outcome. Finally, to allow implementation of knowledge on diverse OA pathophysiological processes, the potency of circulating miRNAs to report on ongoing OA pathophysiological process in joint tissues was established. Such insights are crucial to stratify respective OA patients that require different therapeutic mode of action, towards precision medicine.

Link to whole thesis