Third party funded individual grant
Acronym: UNPLOK
Start date : 17.06.2023
End date : 16.06.2026
Membranous glomerulonephritis (MGN) is caused by autoantibodies (AABs) against podocyte autoantigens. The most common AAB is PLA2R AK. However, it is still unclear what triggers AAB production and how AABs reach the sub-epithelial region, since the glomerular filtration barrier is normally impermeable to AABs. We have already shown that podocyte and endothelial microRNAs (miRs) that regulate nephronectin - an extracellular matrix protein produced by podocytes - play a role in MGN. We suspect that particulate matter or micro-/nanoplastics (MNPs) induce downregulation of structures in the GBM, thus promoting AAB passage and also inhibiting podocyte autophagy. This hypothesis will be tested using three-dimensional glomerular cell culture models, in transgenic zebrafish models and in mice including autophagy and proteinuria reporter lines as well as inducible podocyte-specific miR overexpressing models and transgenic Pla2R mice. Both the glomerular cell culture models and the zebrafish and mice will be exposed to particulate matter and MNP via the medium, water or via a versatile aerosol concentration enrichment system. The therapeutic potential of a miRAntagomir will also be tested after exposure to particulate matter and MNP. The samples will be analyzed using miR/mRNA arrays, Western blot, proteinuria and autophagy assays and a combination of multi-modal, cross-scale analyses including Raman spectroscopy, nanoGPS technology, scanning electron and ion microscopy (FIB/SEM) and scanning ion conductance microscopy (SCICM). Kidney biopsies from patients with MGN will also be taken into account. The comprehensive data will be correlated and quantitatively evaluated using machine learning and could provide clues for diagnostic and therapeutic options for MGN.