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Thomas Beiter

Publications and source records attributed to Thomas Beiter.

4 recordsLinked to original sources

Experimental autoimmune neuritis induces differential microglia activation in the rat spinal cord.

The reactive spatial and temporal activation pattern of parenchymal spinal cord microglia was analyzed in rat experimental autoimmune neuritis (EAN). We observed a differential activation of spinal cord microglial cells. A significant increase in ED1(+) microglia predominantly located in the dorsal horn grey matter of lumbar and thoracic spinal cord levels was observed on Day 12. As revealed by morphological criteria and by staining with further activation markers [allograft inflammatory factor 1 (AIF-1), EMAPII, OX6, P2X(4)R], reactive microglia did not reach a macrophage-like state of full activation. On Day 12, a significant proliferative response could be observed, affecting all spinal cord areas and including ED1(+) microglial cells and a wide range of putative progenitor cells. Thus, in rat EAN, a reactive localized and distinct microglial activation correlating with a generalized proliferative response could be observed.

Animals↗

Examination of tumorigenesis of precursor lesions in bladder cancer by in situ hybridization.

Through examinations using fluorescence in situ hybridization (FISH) of chromosomes 1 and 9, we tried to obtain more information on dysplasia and carcinoma in situ (Cis) in relation to the oncogenesis of bladder cancer. 63 paraffin sections (dysplasia grades I-III and Cis) were evaluated, and 8 negative sections functioned as a control group. For FISH, DNA samples of CEP 1 and 9 (alpha satellites) were chosen. Gains (aneuploidy) or losses (monosomy) of chromosomal material were determined microscopically. Dysplasia grades I-III showed a 5-18% aberration in chromosome 1 aneuploidy and a 19-29% aberration in monosomy 9. Cis revealed 27% aneuploidy of chromosomes 1 and 9. Although at present dysplasia grade III and Cis of the bladder are viewed as histopathologically identical, we examined both molecular genetic differences in chromosome 9. As referred to in the literature we found the same genetic aberrations for dysplasias (grades I-III) and noninvasive papillary bladder tumors as well as for Cis and solid invasive bladder cancer.

Adult↗

Nanovesicular vaccines: exosomes.

Exosomes are small membrane vesicles derived from late endosome. They are about 30--100 nm in diameter. The secretion of exosomes is a process in which multivesicular bodies fuse with the cell membrane, and all cells that contain multivesicular endocytic compartments could theoretically secrete exosomes. The surprising biological functions of exosomes are only slowly being unveiled, but it is already clear that they serve to remove obsolete membrane proteins and act as messages of inter-cellular communication. Exosomes derived from tumor or antigen-presenting cells have been extensively investigated. They are released into the extracellular environment and fuse with the membranes of neighboring cells, delivering membrane and cytoplasmic proteins from one cell to another. Exosomes carry immunorelevant structures which play important roles in immune response, such as MHC molecules, costimulatory molecules, heat shock proteins, and naive tumor antigens. Therefore they have been suggested as potential vaccines. Consequently, exosomes have shown considerable anti-tumor effect in several studies and are in phase I clinical trials.

Animals↗