Effects of GFP on COX-2 expression and PGE₂ production in ECs. (A) Control uninfected cells and cells infected with AdGFP (50-200 MOI) or AdNull (200 MOI) for 48 hours. Cell lysates were probed for COX-2 expression by Western blotting and (B) culture supernatants were analyzed for PGE₂. Production of PGE₂ was determined by enzyme immunoassay as described in “Materials and methods.” The columns are the means, and the bars are the SD (n = 4); *P < .05 compared with control; **P < .01 compared with control. (C) Cells were treated without or with recombinant human HSP70 (5 μg/mL) or heat-inactivated HSP70 (5 μg/mL) for 24 hours. Immunoblots were probed with antibody specific for COX-2.