APOH and Sjogren syndrome: To explore the clinical value of autoantibody-based subgroup profiling, two of our analyzed studies [23,27] used a two-step cluster approach based on the seropositivity of patients for various autoantibodies (anti-CL, ANA, anti-b2GP1, anti-dsDNA, anti-RNP, anti-RibP, anti-ENA [including anti-Sm, anti-Sjogren’s syndrome (SS)A, and anti-SSB], anti-scl70, and Jo-1).