TY  - JOUR
A1  - Elias, Johannes
A1  - Schouls, Leo M.
A1  - van de Pol, Ingrid
A1  - Keijzers, Wendy C.
A1  - Martin, Diana R.
A1  - Glennie, Anne
A1  - Oster, Philipp
A1  - Frosch, Matthias
A1  - Vogel, Ulrich
A1  - van der Ende, Arie
T1  - Vaccine Preventability of Meningococcal Clone, Greater Aachen Region, Germany
N2  - No abstract available
KW  - IMD
Y1  - 2010
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-68083
ER  - 
TY  - JOUR
A1  - Schubert-Unkmeir, Alexandra
A1  - Konrad, Christian
A1  - Slanina, Heiko
A1  - Czapek, Florian
A1  - Hebling, Sabrina
A1  - Frosch, Matthias
T1  - Neisseria meningitidis Induces Brain Microvascular Endothelial Cell Detachment from the Matrix and Cleavage of Occludin: A Role for MMP-8
N2  - Disruption of the blood-brain barrier (BBB) is a hallmark event in the pathophysiology of bacterial meningitis. Several inflammatory mediators, such as tumor necrosis factor alpha (TNF-a), nitric oxide and matrix metalloproteinases (MMPs), contribute to this disruption. Here we show that infection of human brain microvascular endothelial cells (HBMEC) with Neisseria meningitidis induced an increase of permeability at prolonged time of infection. This was paralleled by an increase in MMP-8 activity in supernatants collected from infected cells. A detailed analysis revealed that MMP-8 was involved in the proteolytic cleavage of the tight junction protein occludin, resulting in its disappearance from the cell periphery and cleavage to a lower-sized 50-kDa protein in infected HBMEC. Abrogation of MMP-8 activity by specific inhibitors as well as transfection with MMP-8 siRNA abolished production of the cleavage fragment and occludin remained attached to the cell periphery. In addition, MMP-8 affected cell adherence to the underlying matrix. A similar temporal relationship was observed for MMP activity and cell detachment. Injury of the HBMEC monolayer suggested the requirement of direct cell contact because no detachment was observed when bacteria were placed above a transwell membrane or when bacterial supernatant was directly added to cells. Inhibition of MMP-8 partially prevented detachment of infected HBMEC and restored BBB permeability. Together, we established that MMP-8 activity plays a crucial role in disassembly of cell junction components and cell adhesion during meningococcal infection.
KW  - Neisseria meningitidis
Y1  - 2010
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-68589
ER  -