DNA polymerase activity and antibody against it in sera of patients with systemic lupus erythematosus.

In the sera of one half of patients with sytemic lupus erythematosus (SLE) the endogenous and exogenous DNA polymerase activities were observed. The simultaneous presence of DNA polymerase activity and the antibodies to denatured DNA in the half of polymerase positive SLE sera was proved. The polymerase activity was not associated with virus-like particles. The endogenous polymerase activity probably used RNA, the exogenous one prefered DNA as a template. The determination of template requirement was complicated by the complexity of SLE sera. The product of polymerase activities were DNA-RNA hybrid and DNA. In some sera of the SLE patients without polymerase activity the antibodies against the polymerase were found. The occurrence of DNA polymerase activity and possible viral origin of SLE was discussed.