Fig. 2.

Sheared serum induces DRE-mediated transcription. (A) The H1L6.1c3 cell line, which harbors a stably integrated DRE-driven luciferase reporter, was grown to confluency on fibronectin-coated slides. In the first part of the experiment, cells (n = 3) were directly exposed to fluid shear stress (direct shear stress) or static conditions (static media) for 24 h. The growth medium “conditioned” by this experiment was then used to treat confluent slides of H1L6.1c3 cells for 24 h. (B) Media were conditioned by shear stress by using perfusion chambers that contained slides with confluent Hepa1c1c7 cells (media conditioned + cells) or slides without cells (media conditioned − cells) for 8 h. Each medium was then used to treat H1L6.1c3 cells (n = 3) for 20 h. (C) A DMEM solution supplemented with 60% vol/vol FBS (DMEM+FBS) and a nonsupplemented DMEM solution were sheared for 2 h. After exposure to shear stress, static FBS was added to the sheared DMEM solution to 60% of total volume. Dilutions of the sheared DMEM+FBS (triangles) and sheared DMEM + static FBS (circles) were used to treat H1L6.1c3 cells (n = 3) for 20 h. (D) HS and FBS were exposed to shear stress for 2 h. H1L6.1c3 cells (n = 3) were treated with a 20% vol/vol (v/v) dilution of each serum for 20 h and then assayed for luciferase activity. ∗, P < 0.05; ∗∗, P < 0.01; ∗∗∗, P 0.001.