Myles J Lewis1, Michael B McAndrew2, Colin Wheeler2, Nicholas Workman2, Pooja Agashe2, Jens Koopmann3, Ezam Uddin2, David L Morris4, Lu Zou5, Richard Stark2, John Anson2, Andrew P Cope6, Timothy J Vyse7. 1. Centre for Experimental Medicine and Rheumatology, William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, EC1M 6BQ, UK. Electronic address: myles.lewis@qmul.ac.uk. 2. Oxford Gene Technology, Unit 15, Oxford Industrial Park, Yarnton, Oxfordshire, OX5 1QU, UK. 3. MedImmune, Aaron Klug Building, Granta Park, Cambridge, CB21 6GH, UK. 4. Department of Medical and Molecular Genetics, King's College London, London, SE1 9RT, UK. 5. Centre for Experimental Medicine and Rheumatology, William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, EC1M 6BQ, UK. 6. Academic Department of Rheumatology, Centre for Molecular and Cellular Biology of Inflammation, King's College London, London, SE1 9RT, UK. 7. Department of Medical and Molecular Genetics, King's College London, London, SE1 9RT, UK. Electronic address: timothy.vyse@kcl.ac.uk.
Abstract
OBJECTIVES: The molecular targets of the vast majority of autoantibodies in systemic lupus erythematosus (SLE) are unknown. We set out to identify novel autoantibodies in SLE to improve diagnosis and identify subgroups of SLE individuals. METHODS: A baculovirus-insect cell expression system was used to create an advanced protein microarray with 1543 full-length human proteins expressed with a biotin carboxyl carrier protein (BCCP) folding tag, to enrich for correctly folded proteins. Sera from a discovery cohort of UK and US SLE individuals (n = 186) and age/ethnicity matched controls (n = 188) were assayed using the microarray to identify novel autoantibodies. Autoantibodies were validated in a second validation cohort (91 SLE, 92 controls) and a confounding rheumatic disease cohort (n = 92). RESULTS: We confirmed 68 novel proteins as autoantigens in SLE and 11 previous autoantigens in both cohorts (FDR<0.05). Using hierarchical clustering and principal component analysis, we observed four subgroups of SLE individuals associated with four corresponding clusters of functionally linked autoantigens. Two clusters of novel autoantigens revealed distinctive networks of interacting proteins: SMAD2, SMAD5 and proteins linked to TGF-β signalling; and MyD88 and proteins involved in TLR signalling, apoptosis, NF-κB regulation and lymphocyte development. The autoantibody clusters were associated with different patterns of organ involvement (arthritis, pulmonary, renal and neurological). A panel of 26 autoantibodies, which accounted for four SLE clusters, showed improved diagnostic accuracy compared to conventional antinuclear antibody and anti-dsDNA antibody assays. CONCLUSIONS: These data suggest that the novel SLE autoantibody clusters may be of prognostic utility for predicting organ involvement in SLE patients and for stratifying SLE patients for specific therapies.
OBJECTIVES: The molecular targets of the vast majority of autoantibodies in systemic lupus erythematosus (SLE) are unknown. We set out to identify novel autoantibodies in SLE to improve diagnosis and identify subgroups of SLE individuals. METHODS: A baculovirus-insect cell expression system was used to create an advanced protein microarray with 1543 full-length human proteins expressed with a biotin carboxyl carrier protein (BCCP) folding tag, to enrich for correctly folded proteins. Sera from a discovery cohort of UK and US SLE individuals (n = 186) and age/ethnicity matched controls (n = 188) were assayed using the microarray to identify novel autoantibodies. Autoantibodies were validated in a second validation cohort (91 SLE, 92 controls) and a confounding rheumatic disease cohort (n = 92). RESULTS: We confirmed 68 novel proteins as autoantigens in SLE and 11 previous autoantigens in both cohorts (FDR<0.05). Using hierarchical clustering and principal component analysis, we observed four subgroups of SLE individuals associated with four corresponding clusters of functionally linked autoantigens. Two clusters of novel autoantigens revealed distinctive networks of interacting proteins: SMAD2, SMAD5 and proteins linked to TGF-β signalling; and MyD88 and proteins involved in TLR signalling, apoptosis, NF-κB regulation and lymphocyte development. The autoantibody clusters were associated with different patterns of organ involvement (arthritis, pulmonary, renal and neurological). A panel of 26 autoantibodies, which accounted for four SLE clusters, showed improved diagnostic accuracy compared to conventional antinuclear antibody and anti-dsDNA antibody assays. CONCLUSIONS: These data suggest that the novel SLE autoantibody clusters may be of prognostic utility for predicting organ involvement in SLEpatients and for stratifying SLEpatients for specific therapies.
Authors: Afshan Sumera; Nur Diana Anuar; Ammu Kutty Radhakrishnan; Hishamshah Ibrahim; Nurul H Rutt; Nur Hafiza Ismail; Ti-Myen Tan; Abdul Aziz Baba Journal: Biomedicines Date: 2020-04-26
Authors: Carolina Muñoz-Grajales; Stephenie D Prokopec; Sindhu R Johnson; Zahi Touma; Zareen Ahmad; Dennisse Bonilla; Linda Hiraki; Arthur Bookman; Paul C Boutros; Andrzej Chruscinski; Joan Wither Journal: Rheumatology (Oxford) Date: 2022-03-02 Impact factor: 7.046