Fig. 6

Increased binding of anti-double-stranded DNS (dsDNA) IgG but not of anti-dsDNA IgM to DNA treated with topoisomerase I (topo I). Calf thymus DNA was incubated with recombinant topo I or bovine serum albumin (BSA) for 30 min. Binding affinity of a anti-dsDNA IgG or b anti-dsDNA IgM from MRL/lpr plasma to modified DNA was assessed by enzyme-linked immunosorbent assay. Data were pooled from three independent experiments. **P < 0.01, by paired t test. ns not significant, OD optical density