0000000000164077
AUTHOR
Reinhard Mentele
Myelin-specific T cells also recognize neuronal autoantigen in a transgenic mouse model of multiple sclerosis
T-cell recognition of autoantigens is important in the development of autoimmune disease. Now, Hartmut Wekerle and his colleagues demonstrate that organ-specific autoimmune responses may be driven by T cells that simultaneously respond to two different autoantigens found within the same target tissue. We describe here the paradoxical development of spontaneous experimental autoimmune encephalomyelitis (EAE) in transgenic mice expressing a myelin oligodendrocyte glycoprotein (MOG)-specific T cell antigen receptor (TCR) in the absence of MOG. We report that in Mog-deficient mice (Mog−/−), the autoimmune response by transgenic T cells is redirected to a neuronal cytoskeletal self antigen, neur…
Purification and partial amino acid sequences of the enzyme vinorine synthase involved in a crucial step of ajmaline biosynthesis.
The acetyl-CoA-dependent enzyme vinorine synthase was isolated from hybrid cell suspension cultures of Rauvolfia serpentina and Rhazya stricta. The sarpagan-type alkaloid gardneral was used as a substrate of the enzyme leading to the ajmalan-type 10-methoxyvinorine. An HPLC-based assay was developed to monitor vinorine synthase activity, which allowed establishing a five step purification procedure combining anion exchange, hydrophobic interaction, hydroxyapatite and gel filtration. Purification resulted in a yield of 0.2% and an approximately 991-fold enrichment of the acetyltransfer activity. SDS-PAGE analysis showed a Mr for the enzyme of approximately 50 kDa. The four peptide fragments …