title: Anti C1q antibodies in cutaneous lupus erythematosus.
abstract: Autoantibodies against C1q are strongly linked to immune-complex disorders like systemic lupus erythematosus (SLE). Although anti-C1q antibodies have received much interest in the recent years, their biological functions remain unclear. Anti-C1q antibodies are strongly associated with lupus nephritis. Recent studies describe apoptosis as a key player in LE pathogenesis and C1q is an important opsonin, playing a central role in the uptake of apoptotic blebs. The aim of this study was to evaluate serum anti C1q antibodies, C1q with circulating immune complexes and correlation between serology and cutaneous apoptosis in patients with cutaneous lupus erythematosus.
  
  
  METHODS
  79 subjects were recruited and divided into 4 groups-13 healthy controls, 26 with discoid chronic lupus (DLE), 23 with systemic lupus erythematosus (SLE) and 17 with subacute lupus erythematosus (SCLE). Blood samples and skin punched-biopsy specimens were performed. Serum anti-C1q antibodies and C1q associated to the immune complexes concentrations were determined by ELISA. Cutaneous caspase-3 expression was evaluated by immunohistochemistry.
  
  
  RESULTS
  SLE and SCLE patients had significantly higher levels of anti-C1q antibodies and serum C1q-CIC levels when compared to healthy controls (p < 0.05). Serum anti-C1q antibodies correlated with proteinuria in SLE patients (p < 0.05). Anti C1q antibodies levels also correlated with cutaneous caspase 3 expression in SLE and SCLE patients (both p < 0.05).
  
  
  CONCLUSIONS
  Anti C1q antibodies might play a pathogenic role in SCLE pathogenesis and being positively associated with cutaneous apoptosis markers might be associated with a negative prognosis and secondary SLE development.
authors.affiliation: III Section Internal Medicine, "Colentina" Clinical Hospital, Bucharest, Romania. plbalanescu@gmail.com
authors.forename: Eugenia
authors.initials: E
authors.lastname: Bălănescu
authors.forename: C
authors.initials: C
authors.lastname: Tănăsescu
authors.forename: P
authors.initials: P
authors.lastname: Bălănescu
authors.forename: Rodica
authors.initials: R
authors.lastname: Olteanu
authors.forename: Camelia
authors.initials: C
authors.lastname: Badea
authors.forename: Brânduşa
authors.initials: B
authors.lastname: Petruţescu
authors.forename: Camelia
authors.initials: C
authors.lastname: Grancea
authors.forename: Codruţa
authors.initials: C
authors.lastname: Vagu
authors.forename: Coralia
authors.initials: C
authors.lastname: Bleotu
authors.forename: Simona
authors.initials: S
authors.lastname: Ruţă
authors.forename: Carmen
authors.initials: C
authors.lastname: Ardeleanu
mesh_terms: D000328:Adult; D001323:Autoantibodies / Q000276:immunology*; D015551:Autoimmunity / Q000276:immunology; D015415:Biomarkers; D053148:Caspase 3 / Q000276:immunology; D015922:Complement C1q / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007155:Immunologic Factors / Q000032:analysis; D008178:Lupus Erythematosus, Cutaneous / Q000276:immunology*; D008179:Lupus Erythematosus, Discoid / Q000276:immunology*; D008180:Lupus Erythematosus, Systemic / Q000150:complications / Q000276:immunology*; D008181:Lupus Nephritis / Q000209:etiology / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D011379:Prognosis
chemical_list: D001323:Autoantibodies; D015415:Biomarkers; D007155:Immunologic Factors; D015922:Complement C1q; D053148:Caspase 3