Cells of the immune system play a key role in the resolution of tissue injuries, inflammation and infections and in regulation of tissue homeostasis. Here we aimed to profile natural product-inspired drug discovery platform, developed by Janssen Incubator, using natural product scaffold-based chemical entities, to aid in identifying new chemical starting points with a disease-relevant mechanisms of action. We used 13 human primary cell-based assays, amongst which several assays target the immune system, to screen approximately 1,600 compounds.
Inflammatory assays utilized for screening include neutrophil migration, activation of B-cells, T-cells, macrophages, dendritic cells (DC) and synovial fibroblasts. Immune cells were isolated from healthy donor buffy coats and synovial fibroblasts were isolated from rheumatoid arthritis patients. Neutrophils were subjected to IL-8-mediated migration in a transwell system. Isolated B-cells were stimulated with CD40L and IL-4 to secrete IL-6. PBMCs were stimulated with anti-CD3/CD28 antibodies to induce IL-2 secretion by T-cells. For macrophage activation, PBMCs were stimulated with LPS to induce TNF-α secretion. Monocytes-derived DCs were stimulated with CD40L+enhancer to produce IL12p40. Synovial fibroblasts were stimulated with platelet-derived micro-particles to induce IL-6 secretion.
Assays were successfully validated using reference compounds and subsequently subjected to screening of the 1,600 compounds resulting in multiple new starting points for a hit-to-lead program. These screens also highlighted which assays could help identify unique, disease-relevant mechanisms of action.