H7 does not inhibit IL-4-induced Jak1, Jak3, or IRS-1 tyrosine phosphorylation.

Ramos cells were starved O/N and were untreated or treated with H7 (100 μmol/L) for 30 minutes and then were stimulated with IL-4 (100 ng/mL) for 10 minutes as indicated. (A) Jak1 and Jak3 were immunoprecipitated, separated by 7.5% SDS-PAGE, and immunoblotted with anti-phosphotyrosine antibody. Shown in the lower panel are protein levels from the same filters blotted again with anti-Jak1 and anti-Jak3. (B) Ramos cells treated as in (A), but immunoprecipitation was carried out with anti-IRS-1 antibody before anti-phosphotyrosine immunoblotting.