Effect of scavenger receptor and RAGE ligands on protein tyrosine phosphorylation and intracellular respiratory burst.A, THP1 monocytes were stimulated with 50 μm Aβ25–35 (Aβ) or 20 μg/ml ofLDL, acetylated LDL (Ac-LDL), maleylated BSA (m-BSA), BSA, BSA plus lactoferrin (BSA Lac), glycated BSA (AGE), or glycated BSA plus lactoferrin (AGE Lac) for 2 min in HBSS. Cells were lysed in RIPA buffer, equal quantities of protein (50 μg) were resolved by SDS-PAGE, and proteins were transferred to PVDF. Tyrosine-phosphorylated proteins were detected by Western blot with 4G10. B, THP1 monocytes were stimulated with 50 μm Aβ25–35 (Aβ) acetylated LDL (Ac-LDL), maleylated BSA (m-BSA), or glycated BSA plus lactoferrin (AGE-L) for 10 min in HBSS containing nitroblue tetrazolium. Cells were pelleted, supernatants were removed, and cells were lysed by sonication in RIPA buffer. Generation of superoxide was measured by the change in absorbance of reduced NBT at 550 nm.