Biomedical subjects

Peter Rieckmann

Publications and source records attributed to Peter Rieckmann.

42 records · Page 3Linked to original sources

PubMed2002

CTLA4 exon 1 dimorphism is associated with primary progressive multiple sclerosis.

The cytotoxic T-lymphocyte antigen 4 (CTLA4) is an important modifier of T-cell activation with down-regulatory properties upon B7 engagement. We investigated the association of the CTLA4 A/G dimorphism in exon 1 (+49) with disease susceptibility, disease course and severity. No differences in the allelic distribution of the G(49) allele between multiple sclerosis (MS) patients and the control group was found. However, the G(49) allele occurred in a significant higher percentage of patients with primary progressive MS compared to patients with bout onset of disease. The results suggest that dysregulation of CTLA4-driven down-regulation of T-cell function due a genetic dimorphism in exon 1 may be involved in the pathogenesis of different MS disease subtypes.

Abatacept↗

PubMed2002

Inflammation in multiple sclerosis: the good, the bad, and the complex.

Inflammation has always been thought of as detrimental in the pathophysiology of multiple sclerosis (MS). However, emerging genetic data, magnetic-resonance-imaging studies, and immunopathological evidence challenge this simplistic view. The evidence leads to the conclusion that inflammation is tightly regulated, and that its net effect may be beneficial in MS, thus explaining some of the results from recent trials of anti-inflammatory agents. We argue that the use of anti-inflammatory drugs to treat MS may not be appropriate in all cases. Precise identification of the inflammatory pathways to be targeted in the different phases of the disease and the timing of such interventions are therefore crucial.

Brain↗

PubMed2002

CNTF is a major protective factor in demyelinating CNS disease: a neurotrophic cytokine as modulator in neuroinflammation.

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS). So far, immunological mechanisms responsible for demyelination have been the focus of interest. However, mechanisms regulating axon maintenance as well as glial precursor-cell proliferation and oligodendrocyte survival might also influence disease outcome. The cytokine ciliary neurotrophic factor (CNTF), which was originally identified as a survival factor for isolated neurons, promotes differentiation, maturation and survival of oligodendrocytes. To investigate the role of endogenous CNTF in inflammatory demyelinating disease, we studied myelin oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalomyelitis (EAE) in CNTF-deficient and wild-type C57BL/6 mice. Disease was more severe in CNTF-deficient mice and recovery was poor, with a 60% decrease in the number of proliferating oligodendrocyte precursor cells (OPCs) and a more than 50% increase in the rate of oligodendrocyte apoptosis. In addition, vacuolar dystrophy of myelin and axonal damage were more severe in CNTF-deficient mice. These specific pathological features could be prevented by treatment with an antiserum against tumor necrosis factor-alpha, suggesting that endogenous CNTF may counterbalance this effect of TNF-alpha (ref. 7). Here we identify a factor that modulates, in an inflammatory environment, glial cell survival and is an outcome determinant of EAE.

Animals↗

PubMed2002

Characteristic gene expression profile of primary human cerebral endothelial cells.

Endothelial cells of blood vessels forming the interphase between systemic circulation and tissues are crucial for maintenance of homeostasis and organ-related functions. Recent experiments support organ-specific endothelial differentiation and suggest differential gene expression patterns in endothelial cells. Here, we compared gene expression in primary human cerebral endothelial cells (HCEC), which are major constituents of the blood brain barrier (BBB), with human umbilical vein endothelial cells (HUVEC) by using cDNA array analysis of 375 genes. Under basal culture conditions, 35 genes were expressed only in HCEC, whereas 20 gene transcripts were detected only in HUVEC. A total of 78 genes were expressed in both endothelial cell types partly with distinct expression levels. Genes expressed by cerebral endothelial cells are important in vasculo- and angiogenesis (VEGF, erbB1) and immunoregulation (OSM-Rbeta, decorin, IL-6) or have growth-supporting properties (brain-derived neurotrophic factor, stem cell factor, transforming growth factor-beta). The differential gene expression profiles were confirmed at the protein level of cell cultures (ELISA, immunoblotting) and human tissues (immunohistochemistry). Identification and further functional characterization of genes specifically expressed by cerebral endothelial cells will have important impact on our understanding of endothelial function at the BBB.

Angiogenesis Inducing Agents↗

PubMed2002

Anti-inflammatory strategies to prevent axonal injury in multiple sclerosis.

Axonal injury in multiple sclerosis has attracted considerable interest during the past few years. It has been demonstrated in association with inflammation within active lesions, but it is also present in normal-appearing white matter. Because axonal loss appears to be responsible for persistent neurological deficits in patients with multiple sclerosis, treatment strategies to prevent damage to neurites and restore function are of paramount importance in controlling the disease process. Some of the currently available immunomodulatory therapies may also reduce axonal damage, as demonstrated using improved imaging technologies, but the precise mechanisms that could protect axons during the inflammatory attack are yet to be identified. Factors that are involved in functional impairment of axonal conduction and those elements that are responsible for direct structural damage to the axon are both potential targets for therapeutic interventions.

Animals↗

PubMed2002

UM 9(5)h and UM 9(5)p, human and porcine noncoding transcripts with preferential expression in the cerebellum.

We compared the gene expression patterns of fetal and adult porcine brains and identified a sequence tag that was more abundant in adult than in fetal brain. The RNA corresponding to the sequence tag has the highest expression level in adult cerebellum. Lower expression levels of the transcript were found in adult cerebrum, pituitary, and uterus, as well as in fetal brain, heart, intestine, kidney, and liver. The sequence tag was used to screen a cDNA library from adult porcine brain. Two independent clones of 2,273 nt and 1,701 nt were isolated. The shorter cDNA is a 5'-truncated form of the longer clone, and both clones have almost identical sequences with multiple start and stop codons in all three reading frames. Screening of two different human brain cDNA libraries with porcine cDNA probes resulted in four overlapping cDNA fragments, which were assembled to one contig of 2,336 nt in length. Like noncoding RNAs, the porcine and human sequences have no common conserved open reading frame and share stretches of high homology interrupted by stretches with almost no homology. The human and porcine RNAs were named UM 9(5)h and UM 9(5)p, respectively. They are part of larger transcripts, which are transcribed from single-copy genes, they have very similar tissue distributions, and their sequences are colinear with the respective genomic fragment.

Animals↗