Research Article

Effect of Infliximab on the UVB-Induced Apoptosis of Keratinocytes Infected by HPV38 E6/E7

Figure 2

Role of TNF-α in UVB-induced apoptosis of HPV38 E6/E7 HaCaT cells. (a) HaCaT cells transduced by empty vector PLXSN or with pLXSN-HPV38 E6/E7 vector were irradiated with UVB (10 mJ/cm²) and harvested 24 hours after irradiation. Soluble TNF-α was measured by ELISA test (Human TNF-α ELISA MAX Deluxe, BioLegend, Ozyme, Saint Quentin, France) in the supernatant. (b) pLXSN-HaCat and HPV38 E6/E7-HaCaT cells were irradiated in phosphate-buffered saline with UVB (10 mJ/cm2) and then incubated in Dulbecco’s Modified Eagles medium with TNF-α (100 ng/mL) and/or infliximab (20 ng/mL) for 24 h. Subsequently, the cells were fixed and stained with propidium iodide (PI), and the percentage of sub-G1 cell population was detected by flow cytometry. The experiments were performed at least three times independently in duplicate. The error bars indicate standard deviation.