Abstract
There is compelling evidence that the enzyme dipeptidyl peptidase (DPP) 9 is involved in inflammation and cell death in macrophages. However, large gaps in our understanding of the exact underlying mechanisms remain. Research has mainly been limited to macrophage cell lines and murine primary macrophages. Therefore, our first objective is to study the effect of the DPP8/9 inhibitor 1G244, currently the most selective inhibitor available, on the production and secretion of cytokines and chemokines by human peripheral blood mononuclear cells, monocyte-derived macrophages, M1, M2 and M4 macrophages. The effect on cell viability will also be evaluated in these primary cells. Our second objective includes the identification of DPP9 interaction partners in the monocytic cell line THP-1 and human primary macrophages. Pull-down experiments using recombinant human DPP9 as a bait, followed by LC-MS/MS identification, as well as proximity ligation assays will be applied. We foresee to identify at least one additional interaction partner apart from the FIIND domain in NLRP1/CARD8. The third objective is to characterize the interaction between DPP9 and the bindings partner(s) identified in objective 2 at the molecular level, using isothermal titration calorimetry and grating-coupled interferometry. After the initial characterization of the interactions, we will use anti-DPP9 antibodies with known epitopes in order to identify the regions in DPP9 that are involved in the interaction.
Researcher(s)
Research team(s)
Project type(s)