Fig. 3

GRP78 secretion by HAEC is increased by cigarette smoke extract (CSE), but not cigarette smoke condensate (CSC). a Representative Western blot for vehicle control (VEH) or CSE (15% for 24 h) – treated cells. GRP78 was present in cell-conditioned medium but not medium alone. CSE increased GRP78 in the medium but not the lysate. β-actin, a highly expressed cytosolic protein, was not detected in the cell-conditioned medium. Group mean data of 5 CSE experiments showing GRP78 values normalized to vehicle control in cell-conditioned medium; in cell lysate; and the ratio of medium GRP78 relative to cell lysate GRP78. CSE significantly increased GRP78 in the medium and the ratio of medium GRP78/lysate GRP78 (p = 0.008 for both). b Representative Western blot for vehicle control or CSC (150 μg for 24 h) – treated HAEC. CSC increased GRP78 in the lysate but not the medium. β-actin was not detected in the cell-conditioned medium. Group mean data of 4 CSC experiments. CSC significantly increased lysate GRP78 (p = 0.03) without affecting GRP78 in the medium or the ratio of medium GRP78/lysate GRP78 (p > 0.1)