Protein Information

ID 1786
Name U1RNP
Synonyms RNP antigen; RNPU1Z; RPU 1; RPU1; SNRP70; Small nuclear ribonucleoprotein 70 kD; Small nuclear ribonucleoprotein 70kD polypeptide (RNP antigen); U1 small nuclear ribonucleoprotein 70 kDa…

Compound Information

ID 864
Name MAA
CAS methylarsonic acid

Reference

PubMed Abstract RScore(About this table)
16769655 Ghirardello A, Zampieri S, Tarricone E, Iaccarino L, Bendo R, Briani C, Rondinone R, Sarzi-Puttini P, Todesco S, Doria A: Clinical implications of autoantibody screening in patients with autoimmune myositis. Autoimmunity. 2006 May;39(3):217-21.
OBJECTIVE: To evaluate the clinical usefulness of serum autoantibody profiling in patients with autoimmune myositis. METHODS: We retrospectively studied 74 consecutive patients: 68 had definite or probable myositis according to Bohan-Peter criteria, six suffered from antisynthetase syndrome with subclinical myopathy. Myositis specific antibodies (MSA) (anti-ARS, -SRP, -Mi-2) were determined by RNA immunoprecipitation or immunoblot, myositis associated antibodies (MAA) (anti-RoRNP, -U1RNP, -PM/Scl, -Ku) by immunoblot. RESULTS: Forty-three patients (58%) were positive for MSA: anti-Jo-1 in 15/27 polymyositis (PM) (55%), 4/33 dermatomyositis (DM) (12%), 1/8 overlap (12%) and 2/6 antisynthetase syndrome (33%); anti-ARS non-Jo-1 in 1/27 PM (4%), 2/33 DM (6%) and 4/6 antisynthetase syndrome (67%); anti-Mi-2 in 1/27 PM (4%) and 11/33 DM (33%); anti-SRP in 3/27 PM (11%) and 1/33 DM (3%). One patient was anti-Jo-1/Mi-2 positive, one anti-Jo-1/SRP positive. Moreover, 27 patients (36%) were positive for MAA: anti-Ro/SSA in 8/27 PM (30%), 7/33 DM (21%), 1/8 overlap (12%), and 3/6 antisynthetase syndrome (50%); anti-U1RNP in 1/27 PM (3.7%), 1/33 DM (3%), and 2/8 overlap (25%); anti-PM/Scl in 2/8 overlap (25%), anti-Ku in 2/8 overlap (25%). Anti-Jo-1 was predominantly associated with PM, anti-Mi-2 was almost exclusively found in DM patients. Anti-ARS antibodies were closely associated with interstitial lung disease and polyarthritis; notably, anti-ARS non-Jo-1 was more frequent in patients without overt muscle alterations. Anti-Ro/SSA antibody was not associated with any disease subset, but significantly more frequent in antisynthetase syndrome. CONCLUSIONS: Searching for MSA and MAA in patients with autoimmmune myositis is recommended because of its diagnostic and clinical value. Anti-ARS non-Jo-1 antibodies seem to preferentially target patients with pulmonary fibrosis without overt myopathy.
2(0,0,0,2)