TY - JOUR T1 - Seroconversion from Anti-Th/To to Anticentromere Antibodies in a Patient with Systemic Sclerosis JF - The Journal of Rheumatology JO - J Rheumatol SP - 1938 LP - 1939 DO - 10.3899/jrheum.170575 VL - 44 IS - 12 AU - MARTIAL KOENIG AU - JEAN-LUC SENÉCAL AU - MICHAEL MAHLER Y1 - 2017/12/01 UR - http://www.jrheum.org/content/44/12/1938.abstract N2 - To the Editor:Antinuclear antibodies (ANA) are involved in the diagnosis of systemic sclerosis (SSc), being present in 90% of the patients1,2,3. In the majority of ANA-positive patients with SSc, a single SSc-specific autoantibody can be detected, i.e. antibodies to centromere protein B (CENP-B)4, topoisomerase I5, RNA Pol-III3, and Th/To1,2,3,6,7. These 4 major autoantibodies are typically mutually exclusive. It has been found that anti-Rpp25 antibodies are an important target of antibodies to the Th/To complex6,7. Also, we discovered an epitope located on the Rpp38 subunit of the Th/To complex as the target of autoantibodies in patients with SSc. Anti-Th/To antibodies have been associated with the limited cutaneous form of SSc and with lung disease8. Case reports with sequential serum samples are valuable tools to study the evolution of autoantibody responses in autoimmune diseases9. We report a case of SSc with seroconversion from anti-Th/To to anti-CENP-B antibodies.The case report was approved by the Research Ethics Board under the … Address correspondence to Dr. M. Mahler, Vice President of Research, Inova Diagnostics Inc., 9900 Old Grove Road, San Diego, California 92131-1638, USA. E-mail: mmahler{at}inovadx.com ER -