My research concerns broad studies on the protein components and diseases of basement membranes. My group has cloned genes and cDNAs for most human basement membrane components, type IV collagens, laminins and perlecan. The discovery of a novel, highly glomerular basement membrane specific type IV collagen α5 chain in 1990, led to the elucidation of the first inherited basement membrane and glomerular disease, Alport syndrome. This was followed-up by identifying laminin gene mutants causing junctional epidermolysis bullosa and congenital muscular dystrophy. The positional cloning of the congenital nephrotic syndrome gene encoding the novel protein nephrin in 1998 was important for nephrology, as it opened up for a new understanding of the molecular structure and crucial role of the podocyte slit diaphragm in the renal filtration system.
I currently apply a systems biology approach to diseases of the renal filter including identification of novel glomerular proteins, molecular signatures of disease processes and identification of susceptibility genes for diabetic nephropathy. Two other main research themes involve specific BM proteins called laminins and their roles in stem cell biology and bacteria-binding scavenger receptors with collagenous structures and their potential for sepsis treatment.