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Jens Pahnke

Publications and source records attributed to Jens Pahnke.

21 records · Page 2Linked to original sources

Gene-expression profiling of experimental autoimmune encephalomyelitis.

Experimental autoimmune encephalomyelitis (EAE) is a mouse model that serves as an experimental tool for studying the etiology, pathogenesis, as well as new therapeutic approaches of multiple sclerosis (MS). EAE is a polygenic chronic inflammatory demyelinating disease of the nervous system that involves the interaction between genetic and environmental factors. Previous studies have identified multiple quantitative trait loci (QTL) controlling different aspects of disease pathogenesis. However, progress in identifying new susceptibility genes outside the MHC locus has been slow. With the advent of new global methods for genetic analysis such as large-scale sequencing, gene expression profiling combined with classic linkage analysis and congenic and physical mapping progress is considerably accelerating. Here we review our preliminary work on the use of gene expression mapping to identify new putative genetic pathways contributing to the pathogenesis of EAE.

Animals↗

Deposition of Alzheimer's beta-amyloid is inversely correlated with P-glycoprotein expression in the brains of elderly non-demented humans.

Deposition of the beta-amyloid peptide (Abeta) in the brain occurs during normal ageing and is substantially accelerated in patients with Alzheimer's disease. Since Abeta is continuously produced in the brain, it has been suggested that a clearance mechanism should exist to prevent its accumulation and subsequent aggregation. Until now, little attention has been paid to the possible role of P-glycoprotein (P-gp), a member of the ATP binding cassette superfamily of transporter proteins, in the pathogenesis of Alzheimer's disease. A recent study demonstrated that Abeta40 and Abeta42 interact directly with P-gp. We therefore hypothesized that Abeta accumulation in the brain would correlate inversely with the degree of vascular P-gp expression. To study early pathogenetic factors that influence the deposition of Abeta, at routine autopsies, brain tissue samples were taken from 243 non-demented subjects who died between the ages of 50 and 91 years. Vascular P-gp expression and the number of Abeta40- and Abeta42-positive senile plaques were assessed immunohistochemically in the medial temporal lobe. In addition, the apolipoprotein E (apoE) genotypes, as well as multiple drug resistance gene 1 ( ) polymorphisms (exon 2, G-1A; exon 21, G2677T/A; exon 26, C3436T), were also determined for each case. P-gp expression was not correlated with genotypes, but we found a significant inverse correlation between P-gp expression and the deposition of both Abeta40 and Abeta42 in the medial temporal lobe. Our results provide the first evidence in human brain tissue that the accumulation of Abeta may be influenced by the expression of P-gp in blood vessels, and suggest that P-gp may influence the elimination of Abeta from brain.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

August 2001: Sellar/suprasellar mass in a 59-year-old woman.

The August 2001 COM. Symptomatic granular cell tumors (GCTs) of the neurohypophysis are rare lesions. They are generally regarded as benign neoplasms, although detailed descriptions of the natural course of the tumors are limited to a few cases. We report on a 59-year-old woman with a large GCT of the neurohypophysis and rapid onset of symptoms. Although lacking definitive signs of malignancy, the tumor showed nuclear polymorphism, proliferative activity, evidence of a mutation of the tumor suppressor gene p53 as well as expression of the apoptosis-inhibiting protein bcl-2. These indices may be useful in defining more precisely the clinicopathological prognosis for neurohypophyseal GCTs.

Biomarkers, Tumor↗