Sodium Lauryl Sulfate causes IL-1α release from normal human keratinocytes: dose response and time course curves

Interleukin 1alfa (IL-1 alfa) is involved in the biological response to irritant as one of the most important inflammatory mediator. The aim of the present study was to evaluate IL-1 alfa production after exposure to Sodium Lauryl Sulfate (SLS) from cultured human keratinocytes, representing a model which enables to asses the in vitro effects of SLS on epidermal cells independently from the skin immune system and barrier alteration.Normal human keratinocytes from plastic surgery were grown in serum free medium. At subconfuency cells were treated with SLS doses ranging from 0.00001 to 0.005%. After one hour exposure the medium was changed. At different time points the supernatant was collected for ELISA, and cells were harvested for Western blot analysis of pro-IL-1 alfa and IL-1 alfa. Extracellular secretion of IL-1alfa from keratinocytes was increased in a dose dependent manner following SLS treatment. The release of IL-1alfa starts at 30 min after exposure to SLS (DL50) reaching a maximum at 3 h.Western blot analysis showed a down regulation of pro-IL-1alfa levels at 1 h, while IL-1 alfa levels remained unchanged.