Antigen-specific stimulation of T cell extracellular acidification by MHC class II-peptide complexes
Nag, B.; Wada, H.G.; Fok, K.S.; Green, D.J.; Sharma, S.D.; Clark, B.R.; Parce, J.W.; McConnell, H.M.
Journal of Immunology 148(7): 2040-2044
1992
ISSN/ISBN: 0022-1767 PMID: 1372021 Document Number: 404044
A specific T cell response to a preformed complex of detergent-solubilized MHC class II molecule and cognate antigenic peptide was observed by monitoring the extracellular acidification. An increase in this rate was observed when the resting 4R3.9 T cell clone specific for the peptide fragment MBP(1-14) of myelin basic protein was exposed to preformed detergent-solubilized IAk-MBP(1-14)A4 complexes. MBP peptide alone, IAk alone, or complexes of IAs-proteolipid protein(139-151) and IAd-OVA(323-339), did not cause significant increases in the acidification rates of the MBP(1-14)-restricted 4R3.9 T cell clone. In addition, BW 5147 T lymphoma cells, which lack TCR, did not show any increase in rate when exposed to IAk-MBP(1-14)A4 complexes. Similar increases in acidification rate were observed in the presence of IL-2, anti-CD3 and anti-TCR antibodies. The enhanced acidification responses were blocked by genistein, a tyrosine kinase inhibitor.