TH and systemic sclerosis: With respect to clinical practice in SSc, the majority of SSc patients carry disease-specific autoantibodies, including antibodies against topoisomerase I, centromere, RNA polymerase I/III, Th/To, U3 RNP, U11/U12, Ku, human upstream-binding factor, U1RNP, and PM-Scl (27, 37, 41, 42).