Reactions of keratinocytes to in vitro millimeter wave exposure

The effects of millimeter waves (MW) on human keratinocytes were studied in vitro using the HaCaT keratinocyte cell line. MW-induced modulation of keratinocyte function was studied in proliferation, adhesion, chemotaxis, and interleukin-1beta (IL-1beta) production assays. Spontaneous proliferation, adhesion to tissue culture plate, random migration, and IL-8- and RANTES induced chemotaxis were not affected by exposure of cells to millimeter waves under the following conditions: frequency, 61.22 GHz; SAR, 770 W/kg; duration of exposure, 15-30 min. However, MW irradiation resulted in a modest but statistically significant increase in the intracellular level of IL-1beta. These data suggest that exposure of human skin (with keratinocytes being the major component of epidermis) to MW can cause activation of basal keratinocytes resulting in an elevated level of IL-1beta production.