Anti-C1q antibodies in systemic lupus erythematosus

Research output: Contribution to journalArticlepeer-review


  • A-M Orbai
  • L Truedsson
  • G Sturfelt
  • O Nived
  • H Fang
  • Gs Alarcón
  • Jt Merrill
  • Pr Fortin
  • In Bruce
  • DA Isenberg
  • Dj Wallace
  • R Ramsey-Goldman
  • S-C Bae
  • Jg Hanly
  • J Sanchez-Guerrero
  • Ae Clarke
  • Cb Aranow
  • S Manzi
  • Mb Urowitz
  • Dd Gladman
  • Kc Kalunian
  • Mi Costner
  • Vp Werth
  • A Zoma
  • S Bernatsky
  • G Ruiz-Irastorza
  • Ma Khamashta
  • S Jacobsen
  • Jp Buyon
  • P Maddison
  • Ma Dooley
  • Rf Van Vollenhoven
  • E Ginzler
  • T Stoll
  • C Peschken
  • Jl Jorizzo
  • Jp Callen
  • Ss Lim
  • Bj Fessler
  • M Inanc
  • Dl Kamen
  • A Rahman
  • K Steinsson
  • Ag Franks
  • L Sigler
  • S Hameed
  • N Pham
  • R Brey
  • Mh Weisman
  • G McGwin
  • Ls Magder
  • M Petri

Colleges, School and Institutes

External organisations

  • Division of Rheumatology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
  • Department of Laboratory Medicine, Section of Microbiology, Immunology and Glycobiology, Lund University, Lund, Sweden.
  • Department of Rheumatology, Skåne University Hospital, Lund, Sweden.
  • Department of Medicine, Division of Clinical Immunology and Rheumatology, University of Alabama at Birmingham, Birmingham, AL, USA.
  • Department of Clinical Pharmacology, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA.
  • Division of Rheumatology, Department of Medicine, Centre Hospitalier Universitaire (CHU) de Québec Axe Maladies Infectieuses et Immunitaires, CRCHU de Québec, Université Laval, Quebec City, Quebec, Canada.
  • University of Manchester
  • Centre for Rheumatology, Research Division of Medicine, London, UK.
  • Cedars-Sinai Medical Center, David Geffen School of Medicine, University of California, Los Angeles, CA, USA.
  • Northwestern University, Feinberg School of Medicine, Chicago, IL, USA.
  • Department of Rheumatology, Hanyang University Hospital for Rheumatic Diseases, Seoul, Korea.
  • Division of Rheumatology, Departments of Medicine and Pathology Capital Health and Dalhousie University, Halifax, Nova Scotia, Canada.
  • Mount Sinai Hospital and University Health Network, Toronto, Ontario, Canada.
  • McGill University Health Centre
  • Feinstein Institute for Medical Research, Manhasset, NY, USA.
  • Department of Medicine, Division of Rheumatology, Allegheny Singer Research Institute, Allegheny General Hospital, Pittsburgh, PA, USA.
  • Toronto Western Hospital Toronto, Ontario, Canada.
  • Division of Rheumatology, Allergy and Immunology, UCSD School of Medicine, La Jolla, CA, USA.
  • North Dallas Dermatology Associates, Dallas, TX, USA.
  • Philadelphia VA Medical Center and University of Pennsylvania, Philadelphia, PA, USA.
  • Lanarkshire Centre for Rheumatology and Hairmyres Hospital, East Kilbride, UK.
  • Autoimmune Diseases Research Unit, Hospital Universitario Cruces Universidad del Pais Vasco, Barakaldo, Spain.
  • Rayne Institute and St Thomas' Hospital London, UK.
  • Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.
  • New York University, New York, NY, USA.
  • Ysbyty Gwynedd, Bangor, UK.
  • University of North Carolina, Chapel Hill, NC, USA.
  • Karolinska University Hospital, Stockholm, Sweden.
  • State University of New York, Downstate Medical Center, Brooklyn, NY, USA.
  • Kantonsspital Schaffhausen, Schaffhausen, Switzerland.
  • University of Manitoba Winnipeg, Manitoba, Canada.
  • Wake Forest University, Winston-Salem, NC, USA.
  • University of Louisville, Louisville, KY, USA.
  • Emory University, Atlanta, GA, USA.
  • Division of Rheumatology, Department of Internal Medicine, Istanbul Medical Faculty, Istanbul University, Istanbul, Turkey.
  • Medical University of South Carolina, Charleston, SC, USA.
  • Landspitali University Hospital, Reykjavik, Iceland.
  • University of Texas Health Science Center, San Antonio, TX, USA.
  • Cedars-Sinai Medical Center, Los Angeles, CA, USA.
  • Department of Epidemiology and Public Health, University of Maryland, Baltimore, MD, USA.
  • Division of Rheumatology, Johns Hopkins University School of Medicine, Baltimore, MD, USA


OBJECTIVE: Anti-C1q has been associated with systemic lupus erythematosus (SLE) and lupus nephritis in previous studies. We studied anti-C1q specificity for SLE (vs rheumatic disease controls) and the association with SLE manifestations in an international multicenter study.

METHODS: Information and blood samples were obtained in a cross-sectional study from patients with SLE (n = 308) and other rheumatologic diseases (n = 389) from 25 clinical sites (84% female, 68% Caucasian, 17% African descent, 8% Asian, 7% other). IgG anti-C1q against the collagen-like region was measured by ELISA.

RESULTS: Prevalence of anti-C1q was 28% (86/308) in patients with SLE and 13% (49/389) in controls (OR = 2.7, 95% CI: 1.8-4, p < 0.001). Anti-C1q was associated with proteinuria (OR = 3.0, 95% CI: 1.7-5.1, p < 0.001), red cell casts (OR = 2.6, 95% CI: 1.2-5.4, p = 0.015), anti-dsDNA (OR = 3.4, 95% CI: 1.9-6.1, p < 0.001) and anti-Smith (OR = 2.8, 95% CI: 1.5-5.0, p = 0.01). Anti-C1q was independently associated with renal involvement after adjustment for demographics, ANA, anti-dsDNA and low complement (OR = 2.3, 95% CI: 1.3-4.2, p < 0.01). Simultaneously positive anti-C1q, anti-dsDNA and low complement was strongly associated with renal involvement (OR = 14.9, 95% CI: 5.8-38.4, p < 0.01).

CONCLUSIONS: Anti-C1q was more common in patients with SLE and those of Asian race/ethnicity. We confirmed a significant association of anti-C1q with renal involvement, independent of demographics and other serologies. Anti-C1q in combination with anti-dsDNA and low complement was the strongest serological association with renal involvement. These data support the usefulness of anti-C1q in SLE, especially in lupus nephritis.

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Original languageEnglish
Publication statusPublished - 14 Aug 2014