SS-56, a novel cellular target of autoantibody responses in Sjogren syndrome and systemic lupus erythematosus

Citation
O. Billaut-mulot et al., SS-56, a novel cellular target of autoantibody responses in Sjogren syndrome and systemic lupus erythematosus, J CLIN INV, 108(6), 2001, pp. 861-869
Citations number
51
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Medical Research General Topics
Journal title
JOURNAL OF CLINICAL INVESTIGATION
ISSN journal
0021-9738 → ACNP
Volume
108
Issue
6
Year of publication
2001
Pages
861 - 869
Database
ISI
SICI code
0021-9738(200109)108:6<861:SANCTO>2.0.ZU;2-N
Abstract
Certain autoimmune disorders, including Sjogren syndrome (SS) and systemic lupus erythematosus (SLE), are characterized by autoantibodies against the Ro/SSA and La/SSB cellular antigens. Although the implication of these auto antibodies in disease pathogenesis is still unclear, it is believed that th e aberrant responses against autoantigens may extend to other proteins that are not yet well defined. In an attempt to analyze the regulated gene expr ession in lymphocytes by an HIV suppressive immunomodulator, we have identi fied and cloned a novel gene encoding a 56-kDa protein, named SS-56, which is structurally related to the 52-kDa Ro/SSA antigen. The new protein showe d primarily perinuclear cytoplasmic localization, and recombinant SS-56 was found to react in ELISA with sera from most patients with SS or SLE. Weste rn blot analysis confirmed the autoantigenic nature of native SS-56 in extr acts from HeLa cells. Interestingly, the incidence of antibodies to SS-56 w as associated with visceral complications in SLE, and roughly half of the 1 7 SS or SLE patients with no detectable antibodies to SSA and SSB antigens presented measurable antibodies against recombinant SS-56. Thus, SS-56 repr esents a new member of the SS family of autoantigens and could become an ad ditional and important diagnostic marker for SS and SLE.