Bernard van den Berg

Bernard van den Berg did his PhD in Immunology at the University of Leiden in 1999 to the role of antibodies against virulence factors of Bordetella pertussis in the protection against infection. He next changed to the field of vascular biology as a postdoctoral fellow at the Department of Medical Physics at the Academic Medical Center (AMC) in Amsterdam with Hans Vink, the Department of Molecular and Vascular Medicine at Beth Israel Deaconess Medical Center (BIDMC), Harvard Medical School in Boston (USA) with William C Aird and Robert D, Rosenberg, and Department of Physiology, Cardiovascular Research Institute Maastricht (CARIM) at Maastricht University, again with Hans Vink. From 2010 he started at the Division of Nephrology of the Einthoven Laboratory for Vascular Medicine of the Leiden University Medical Center in Leiden with Ton Rabelink and Anton Jan van Zonneveld.

For several years, my research interest is focused at the pathophysiology of the vascular endothelial glycocalyx, which serves as a protective barrier between the endothelium and blood. We use various techniques to visualize the elusive matrix on the endothelial surface using electron microscopy (see figure 1), 2-photon- and confocal laser scanning microscopy and a combination of cellular, molecular, genetic and biochemistry approaches to understand how endothelial cells maintain their extracellular matrix coverage and how these long saccharide polymers contribute to cellular health and interaction with neighboring cells, such as pericytes.

Figure 1. Transmission electron microscopic images of a cupromeronic blue stained glomerulus. Detail of glomerular filtration barrier (right panel) consisting of the podocytic foot processes, glomerular basal membrane, endothelial cells and endothelial glycocalyx covering the cell surface and filling up the fenestrae [Am. J. Pathol. 2013].

The glycocalyx is a network of long-unbranched polysaccharides projecting from the surface of endothelial cells which lines blood vessels. Although the endothelial glycocalyx has been identified morphologically several decades ago and a number of physiological and pathological functions have been attributed, the exact molecular composition and function remains largely unknown. In our group, we focus on the function of especially the glomerular endothelial glycocalyx in its role in the permeability barrier and binding of leukocytes and cytokine/chemokine handling, when disturbed can lead to diabetic nephropathy, responsible for the majority of end-stage renal failure and loss of kidney function in diabetes.