SB-747651A

SB-747651A is an ATP-competitive mitogen- and stress-activated kinase 1 (MSK1) inhibitor with an IC₅₀ of 11 nM. SB-747651A also inhibits PRK2, RSK1, p70S6K and ROCK-II. SB-747651A can be used for inflammation research^[1]. IC50 & Target: IC50: 11 nM (MSK1)^[1] In Vitro: SB-747651A (5 μM; neutrophils) affects CXCL2-induced intraluminal crawling of neutrophils in a Mac-1-dependent manner. SB-747651A thwarts the intraluminal crawling of adherent neutrophils to optimal sites of emigration. SB-747651A (5 μM; neutrophils) significantly increases transmigration time and detachment time. SB-747651A affects mechanisms that regulate transendothelial migration of neutrophils in response to CXCL2 chemotactic gradient. SB-747651A inhibits the migration speed of extravascular chemotaxing neutrophils but does not affect their directionality in response to CXCL2 chemotactic gradient^[2]. In Vivo: SB747651A (3 mg/kg; intrascrotal injection) results in increased neutrophil adhesion 3.5~4.5 hours following stimulation with CXCL2 as compared to the effect of CXCL2^[3].
SB-747651A (3 mg/kg; i.p.) affects neutrophil extravasation by increasing neutrophil emigration only at 3 and 4 hours in mouse peritonitis model of acute inflammation^[3].