Concurrent strong tyrosine phosphorylation of a 42,000 MW ERK and a 100,000 MW protein is associated with IL-2 production in human Jurkat T cells.
The tyrosine phosphorylated protein(s) responsible for the signalling for interleukin-2 (IL-2) production has not been clearly defined. In this study, the relationship between IL-2 production and the protein tyrosine phosphorylation pattern of human Jurkat T cells was investigated using phosphotyrosine immunoblotting analysis. With anti-CD3 or anti-CD2 activation the cells showed only a low (anti-CD3) or a moderate (anti-CD2) level of tyrosine phosphorylation of a 42,000 MW external signal-regulated kinase (ERK), which was accompanied by undetectable (anti-CD3) or low level (anti-CD2) IL-2 production. In the presence of phorbol myristate acetate (PMA), large amounts of IL-2 were induced by both anti-CD3 and anti-CD2 stimulation, which was accompanied by strong concurrent tyrosine phosphorylation of the 42,000 MW ERK and a 100,000 MW protein. PMA alone, which induced high levels of tyrosine phosphorylation of the ERK protein, neither induced any detectable IL-2 nor increased the level of tyrosine phosphorylation of the 100,000 MW protein. These observations suggest that concurrent tyrosine phosphorylation of the 42,000 MW ERK and a 100,000 MW protein may be required for IL-2 production.
Song
L
L
Clinical Immunology Section, National Institute on Aging, NIH, Baltimore, MD 21224.
Adler
W H
WH
Chung
S
S
Kim
Y H
YH
TenBrook
J
J
Collins
G D
GD
Nagel
J E
JE
D015703:Antigens, CD / Q000276:immunology; D000945:Antigens, Differentiation, T-Lymphocyte / Q000276:immunology; D018801:CD2 Antigens; D017252:CD3 Complex / Q000276:immunology; D002478:Cells, Cultured; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D007376:Interleukin-2 / Q000096:biosynthesis*; D008213:Lymphocyte Activation / Q000276:immunology; D008970:Molecular Weight; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism*; D011971:Receptors, Immunologic / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014443:Tyrosine / Q000502:physiology*
D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D018801:CD2 Antigens; D017252:CD3 Complex; D007376:Interleukin-2; D011971:Receptors, Immunologic; D014443:Tyrosine; D011494:Protein Kinases; D013755:Tetradecanoylphorbol Acetate