Supplementary Table 1. Summary of discussed studies on biomarkers for predicting conversion to MS and MS diagnosis Biomarker CXCL13 Cohorts of the initial Novel information Cohorts of the confirmation studies study (number of obtained in 2012– (number of patients) patients) 2015 Early MS conversion CIS-CIS follow-up Confirmation of initial CIS n = 69, RRMS n = 389 SPMS n = 54 to CDMS1,2 n = 46, CIS-MS clinical purpose3 PPMS n = 28, OIND n = 223, CIS n = 56, HC Clinical purpose n = 273 follow-up n = 45, tension headache controls n = 301 CIS n = 79, RRMS n = 323, SPMS = 40, PPMS n = 24, OND n = 181, OIND n = 1762 IgM OCB Early MS conversion MS-OCB+ n = 29, MS- Confirmation of initial to CDMS4–7 OCB- n = 525 clinical purpose10,11 CIS follow-up n = 20510, CIS follow-up n = 2411 Cohort 1 PPMS n = 80, Cohort 2 PPMS n = 678 RRMS follow-up n= 298 RRMS n = 21, PPMS subgroup identification8 PPMS n = 1, CDMS n = 549 KFLC Diagnosis of early CIS n = 3, CDMS n = 18, non-MS Confirmation of initial CIS n = 69, RRMS n = 60, PPMS n = 5, OIND MS12–14 neurological diseases clinical purpose15,17 n = 8915 n = 3715 CIS-CIS follow-up n = 38, CIS-MS follow-up CIS-MS n = 15, MS n = 39, OIND n = 77, viral/bacterial infections n = 33, OIND n = 8 n = 2017 OND n = 3316 CIS-MS n = 29, MS n = 70, non-CNS control n = 45, OIND n = 7817 MRZ reaction Diagnosis and MS n = 42, NMO prognosis of early n = 209 CIS-CIS MS9,18,19 n = 40, CIS-MS Confirmation of initial MS n = 47, siblings OCB+ n = 9, siblings OCB- clinical purpose20–22 n = 37 HC n = 5020 CIS n = 7 RRMS n = 6121 non-CNS-autoimmune neurological disorders n = 4918 n = 37, OIND n = 16, RRMS n = 26, SPMS n = 12, PPMS n = 822 MS n = 42, paraneoplastic neurological disorder n = 3419 CHI3L1 Early MS conversion to CDMS23–25 CIS-CIS n = 30, CISMS n = 3024 Confirmation of initial clinical purpose26–28 RRMS n = 156, SPMS n = 30, PPMS n = 66, HC n = 5726 cohort 1 RRMS n = 21, control n = 21, cohort 2 RRMS n = 21, control n = 21, RRMS n = 24, SPMS n = 24, NMO n = 12, Progression29 cohort 3 CIS n = 40, RRMS n = 38, progressive MS n = 16, control n = 2928 OIND n = 24, HC n = 2423 CIS follow up n = 8627 CIS = 109, RRMS n = 19229 MS n = 0, Alzheimer disease n = 10, ALS n = 10, stroke n = 10, HC n = 1925 NfL Diagnosis and RRMS n = 5, prognosis for early Alzheimer diseases MS30,31 n = 5, ALS n = 5, Confirmation of initial clinical purpose32–35 CIS-CIS n = 23, CIS-MS n = 19, CDMS n = 23 OND/HC n = 3,267 CIS-CIS n = 98, CIS-MS n = 10035 vascular dementia n = 531 CIS n = 67, OND n = 1834 CIS n = 38, RRMS CIS n = 62, RRMS n = 38, SPMS n = 25, n = 42, SPMS n = 28, PPMS n = 23, controls n = 7232 PPMS n = 6, nonCNS controls n = 28, OND n = 18, OIND n = 3930 miRNA-20a-5p Diagnosis of early RRMS n = 24, SPMS Confirmation of initial MS36 n = 17, PPMS n = 18, clinical purpose37 CIS n = 25, RRMS n = 25, HC n = 5037 HC n = 3736 miRNA-22-5p *Anti-KIR4.1 Diagnosis of early CIS n = 25, RRMS Confirmation of initial CIS n = 25, RRMS n = 25, HC n = 5037 MS MS37 n = 25, HC n = 5037 clinical purpose37,38 n = 4, HC n = 438 . . Diagnosis of a subset cohort 1: CIS n = 44, RRMS n = 49, SPMS of early MS39–41 n = 19, PPMS n = 10, OND n = 77, HC n = 14 . . . Differential diagnosis Cohort 2: CIS n = 53, RRMS n = 91, SPMS MS-NMO40 n = 1, PPMS n = 1, OND n = 130 HC n = 8 Cohort 3 CIS n = 49, RRMS n = 77, OND n = 12839 MS n = 286, HC n = 99, OND n = 10941 MS n = 268, OND n = 46, HC n = 4540 Blue background indicates a CSF biomarker, purple indicates a CSF+blood biomarker, and red indicates a blood biomarker. *) Inconclusive results Abbreviations: ALS; amyotrophic lateral sclerosis, Anti KIR4.1 Anti-glial inward rectifying potassium channel 4.1, CDMS; clinical definite multiple sclerosis , CHI3L1, chitinase-3-like protein 1, CIS; clinical isolated syndrome, CNS; central nervous system, CSF; cerebrospinal fluid, CXCL13, CXC motif chemokine 13, HC; healthy controls, IgG, immunoglobulin G, IgM; immunoglobulin M, KFLC, kappa free light chains, miRNA, micro RNA, MRZ, measles, rubella, zoster, MS; multiple sclerosis, NfL; neurofilament light chain; NMO; neuromyelitis optica, OCBs; oligoclonal bands, OIND; other inflammatory neurological diseases OND; other neurological diseases, PPMS; primary progressive multiple sclerosis , RRMS; relapsing remitting multiple sclerosis, SPMS; secondary progressive multiple sclerosis. 1. 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