Journal
JOURNAL OF BIOLOGICAL CHEMISTRY
Volume 278, Issue 11, Pages 9928-9937Publisher
AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC
DOI: 10.1074/jbc.M212868200
Keywords
-
Categories
Funding
- NIMH NIH HHS [MH59222] Funding Source: Medline
- NINDS NIH HHS [NS14609] Funding Source: Medline
Ask authors/readers for more resources
T lymphocytes with unusually high expression of the voltage-gated Kv1.3 channel (Kv1.3 high cells) have been implicated in the pathogenesis of experimental autoimmune encephalomyelitis, an animal model for multiple sclerosis. We have developed a fluoresceinated analog of ShK (ShK-F6CA), the most potent known inhibitor of Kv1.3, for detection of Kv1.3 high cells by flow cytometry. ShK-F6CA blocked Kv1.3 at picomolar concentrations with a Hill coefficient of I and exhibited >80-fold specificity for Kv1.3 over Kv1.1 and other K-v channels. In flow cytometry experiments, ShK-F6CA specifically stained Kv1.3-expressing cells with a detection limit of similar to600 channels per cell. Rat and human T cells that had been repeatedly stimulated 7-10 times with antigen were readily distinguished on the basis of their high levels of Kv1.3 channels (>600 channels/cell) and ShK-F6CA staining from resting T cells or cells that had undergone 1-3 rounds of activation. Functional Kv1.3 expression levels increased substantially in a myelinspecific rat T cell line following myelin antigen stimulation, peaking at 15-20 h and then declining to baseline over the next 7 days, in parallel with the acquisition and loss of encephalitogenicity. Both calcium- and protein kinase C-dependent pathways were required for the antigen-induced Kv1.3 up-regulation. ShK-F6CA might be useful for rapid and quantitative detection of Kv1.3(high) expressing cells in normal and diseased tissues, and to visualize the distribution of functional channels in intact cells.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available