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Franz X Weilbach

Publications and source records attributed to Franz X Weilbach.

4 recordsLinked to original sources
PubMed2006

Phagocytosis of apoptotic inflammatory cells downregulates microglial chemoattractive function and migration of encephalitogenic T cells.

Apoptosis of autoaggressive T cells in the central nervous system (CNS) and subsequent phagocytosis by microglia is probably crucial in the rapid resolution of the inflammatory infiltrate in T cell mediated neuroinflammatory diseases. In addition to mere clearance, phagocytosis of apoptotic leukocytes results in the downregulation of different microglial immune functions. Chemoattractive functions of Lewis rat microglia and secretion of chemokines and matrix-metalloproteinases (MMPs) were investigated after phagocytosis of apoptotic T cells in vitro. In a modified Boyden chamber assay migration of encephalitogenic T cells toward LPS-stimulated microglial supernatants after phagocytosis of apoptotic thymocytes was reduced by 24.9% in comparison to interaction with viable target cells (P < 0.001). Phagocytosis of apoptotic cells downregulated CC-chemokine ligand (CCL)-5-secretion by LPS-stimulated microglia by 66.2% (P < 0.001), whereas there was only a trend toward decreased CCL2-secretion. As determined by gelatinase-zymography, secretion of MMP-9 by microglia was decreased after phagocytosis of apoptotic cells, whereas MMP-2 secretion was not altered. These mechanisms may reduce further recruitment of pathogenic inflammatory cells into the CNS-lesion and thus contribute to the active resolution of the inflammatory infiltrate and termination of the autoimmune attack.

Animals↗
PubMed2004

Heparin and air filters reduce embolic events caused by intra-arterial cerebral angiography: a prospective, randomized trial.

BACKGROUND: Intra-arterial cerebral angiography is associated with a low risk for neurological complications, but clinically silent ischemic events after angiography have been seen in a substantial number of patients. METHODS AND RESULTS: In a prospective study, diffusion-weighted magnetic resonance imaging (DW-MRI) before and after intra-arterial cerebral angiography and transcranial Doppler sonography during angiography were used to evaluate the frequency of cerebral embolism. One hundred fifty diagnostic cerebral angiographies were randomized into 50 procedures, each using conventional angiographic technique, or systemic heparin treatment throughout the procedure, or air filters between the catheter and both the contrast medium syringe and the catheter flushing. There was no neurological complication during or after angiography. Overall, DW-MRI revealed 26 new ischemic lesions in 17 patients (11%). In the control group, 11 patients showed a total of 18 lesions. In the heparin group, 3 patients showed a total of 4 lesions. In the air filter group, 3 patients exhibited a total of 4 lesions. The reduced incidence of ischemic events in the heparin and air filter groups compared with the control group was significantly different (P=0.002). Transcranial Doppler sonography demonstrated a large number of microembolic signals that was significantly lower in the air filter group compared with the heparin and control groups (P<0.01), which did not differ from each other. CONCLUSIONS: Air filters and heparin both reduce the incidence of silent ischemic events detected by DW-MRI after intra-arterial cerebral angiography and can potentially lower clinically overt ischemic complications. This may apply to any intra-arterial angiographic procedure.

Adult↗
PubMed2002

Does Down's syndrome protect against multiple sclerosis?

BACKGROUND: A higher incidence of certain autoimmune disorders has been reported in Down's syndrome (DS) but only 1 case of DS associated with multiple sclerosis (MS) has been published to date. METHODS: We performed a calculation based on population and prevalence data of each condition to estimate the expected coprevalence of both diseases. As no published data on DS prevalence are available, a rough estimate was calculated from live birth rates and published life tables. RESULTS: In a total of 116,939 assumed cases of patients with DS in Western Europe 102 patients with concordant MS would be expected at any time point according to the incidence of MS, but only 1 case was reported. CONCLUSION and HYPOTHESIS: We propose the hypothesis that despite a propensity in DS for certain autoimmune diseases there is a negative association of DS and MS. Genes located on chromosome 21 may thus confer protection against MS. Candidate genes for protective immunomodulation might include interferon receptor I and II and S100b. Substantiated by further epidemiologic data, the identification of these and other chromosome 21 gene products may provide new hints for the understanding of modulatory genes in the pathogenesis of MS. In more general terms, this negative association also may allow to study basic principles of how certain candidate genes might act on autoimmune disease expression.

Down Syndrome↗