Antibody specificities of Thai and Australian scleroderma sera with topoisomerase I recombinant fusion proteins.
DS Cram, N Fisicaro, LJ McNeilage, RL Coppel, LC Harrison
J Immunol | Published : 1993
Autoantibodies that react with the nuclear enzyme topoisomerase I (Topo I) are used as a diagnostic marker of diffuse scleroderma. To better define immune reactivity to Topo I, antibody epitopes in two patient populations were analyzed using recombinant Topo I proteins. Two overlapping partial cDNA clones encoding the complete amino acid sequence of Topo I were isolated from human placenta. Using the polymerase chain reaction, specific regions of Topo I were amplified and cloned into the pGEX expression vectors. To map Topo I epitopes, recombinant fusion proteins were analyzed by immunoblotting with 66 anti-Topo I sera from Thai and Australian patients with diffuse scleroderma. Six distinct ..View full abstract