FIGURE 3.

LPS-induced Eps8 increases the phagocytic activity of macrophages. A, RAW264.7 cells treated without or with LPS (100 ng/ml) for 24 and 48 h (left). Age-matched rats were intraperitoneally administered with sterile PBS (−) or LPS (1 mg/kg), and their PEMs were collected after 24 h (right). Total lysates (100 μg) from each sample were Western immunoblotted with antibodies as indicated. B, RAW, Ctrl, and Eps8-attenuated (siEps8-346-1 and -2) cells were stimulated without or with LPS (100 ng/ml) for 24 and 48 h. Then either these cells were lysed and their lysates were Western immunoblotted with antibodies as indicated (B), or they were incubated with GFP-E. coli (C) at 37 °C for 1 h to determine their ability to phagocytose E. coli. D, PEMs (1 × 10⁶ cells) from C57BL/6 mice were infected with lentivirus (MOI = 3) encoding luciferase siRNA (Ctrl) or eps8 siRNA (siEps8-503). After 2 days, PEMs were stimulated without (−) or with LPS (100 ng/ml) for 24 h. Then either PEMs were lysed and the lysates (100 μg) were Western immunoblotted with antibodies as indicated (left), or they were incubated with GFP-E. coli at 37 °C for 1 h to determine their ability to uptake E. coli (right). The arrow indicates the position of active Src.