Cells were treated with either BA or with NAC and exposed to 100 mJ/cm2 UVB as described in the Materials and Methods section. Western blot analysis was performed to determine the protein expression using TLR4 pathway proteins specific antibodies, including TLR4, MyD88, TRIF, TRAF6, NF-κB, iNOS and COX-2. There was an up-regulation of TLR4 and its downstream targets after UVB exposure (p<0.05). However, BA treatment inhibited the up-regulation of the above proteins induced by UVB exposure (p<0.05). The representative blots are shown from three independent experiments. Values are given as mean ± SD (n = 3). (#P<0.05 vs control; *P > 0.05 and **P > 0.01 vs UVB).