PI-3 kinase activity associates with RAFTK in THP1 cells. THP1 cells were stimulated with either 1,000 U/mL or 2 μg/mL LPS for 2 minutes and lysed in RIPA buffer without sodium deoxycholate. Lysates were immunoprecipitated with either anti-RAFTK, normal rabbit serum control, or anti–PI-3 kinase p85 antibody. Immune complexes were absorbed to sepharose-A beads for 3 hours, washed, and subjected to PI-3 kinase assay. Lipids were extracted using methanol:chloroform (1:1) and spotted on oxalate-impregnated silica gel TLC plates. Samples were subjected to ascending chromatography using a methanol:chloroform:water:ammonium hydroxide solvent system. TLC plates were dried and samples were visualized by autoradiography.