Estrogenic xenobiotics increase expression of SS-A/Ro autoantigens in cultured human epidermal cells

SS-A/Ro autoantibodies are detected at high levels in patients with autoimmune diseases such as systemic lupus erythematosus. It has been reported that natural estrogen is capable of inducing cell surface expression of SS-A/Ro autoantigens in human epidermal keratinocytes. In this study, we analysed, by reverse transcriptase polymerase chain reaction and immunohistochemistry, the effects of estrogenic xenobiotics (i.e. environmental estrogens) on the expression of 52-kDa SS-A/Ro autoantigen in cultured keratinocytes. At a concentration of 10 microM, various estrogenic xenobiotics derived from plants, insecticides, or detergents induced up to a 3-fold increase in 52-kDa SS-A/Ro mRNA levels in human keratinocytes compared with untreated cells. The immunohistochemistry results paralleled the reverse transcriptase polymerase chain reaction results. These findings suggest that environmental stimulation can induce the expression of autoantigens such as SS-A/Ro.