Binding of naturally occurring anti-DNA antibodies to estradiol

Binding of naturally occurring human anti-DNA autoantibodies to beta-estradiol and native DNA has been investigated. Sera from seven SLE patients were tested for their reactivity with beta-estradiol and native calf thymus DNA. Solid Phase enzyme immunoassay was performed using both colorigenic and fluorogenic substrates. The results show enhanced binding of human anti-DNA autoantibodies to beta-estradiol as compared to native DNA. This was further substantiated by increased binding of affinity purified SLE IgG to beta-estradiol. These results suggest a role for female sex hormone in the etiopathogenesis of SLE and are significant vis-a-vis female predominance of SLE.