Distinctive profile of monomeric and polymeric anti-SSA/Ro52 immunoglobulin A1 isoforms in saliva of patients with primary Sjögren's syndrome and Sicca

Samantha Chiang; Tristan Grogan; Sarah Kamounah; Fang Wei; Nabihah Tayob; Ju Yeon Kim; Jin Kyun Park; David Akin; David A Elashoff; Anne Marie Lynge Pedersen; Yeong Wook Song; David T W Wong; David Chia

doi:10.1136/rmdopen-2023-003666

Distinctive profile of monomeric and polymeric anti-SSA/Ro52 immunoglobulin A1 isoforms in saliva of patients with primary Sjögren's syndrome and Sicca

RMD Open. 2024 Apr 10;10(2):e003666. doi: 10.1136/rmdopen-2023-003666.

Authors

Affiliations

¹ UCLA School of Dentistry, Los Angeles, California, USA.
² Department of Medicine Statistics Core, University of California, Los Angeles, Los Angeles, California, USA.
³ Oral Biology and Immunopathology/Oral Medicine & Pathology, University of Copenhagen Faculty of Health and Medical Sciences, Copenhagen N, Denmark.
⁴ Data Science, Dana-Farber Cancer Institute, Boston, Massachusetts, USA.
⁵ Rheumatology, Seoul National University Hospital, Seoul, Korea.
⁶ Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
⁷ Section for Oral Biolology and Immunopathology, Oral Medicine and Pathology, Department of Odontology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark ysong@snu.ac.kr amlp@sund.ku.dk dtww@ucla.edu dchia@mednet.ucla.edu.
⁸ Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea ysong@snu.ac.kr amlp@sund.ku.dk dtww@ucla.edu dchia@mednet.ucla.edu.
⁹ UCLA School of Dentistry, Los Angeles, California, USA ysong@snu.ac.kr amlp@sund.ku.dk dtww@ucla.edu dchia@mednet.ucla.edu.
¹⁰ Department of Pathology and Laboratory Medicine, University of California, Los Angeles, Los Angeles, California, USA ysong@snu.ac.kr amlp@sund.ku.dk dtww@ucla.edu dchia@mednet.ucla.edu.

Abstract

Objective: Primary Sjögren's syndrome (pSS) is the second most common chronic autoimmune connective tissue disease. Autoantibodies, immunoglobulin (IgG) anti-SSA/Ro, in serum is a key diagnostic feature of pSS. Since pSS is a disease of the salivary gland, we investigated anti-SSA/Ro52 in saliva.

Methods: Using a novel electrochemical detection platform, Electric Field-Induced Release and Measurement, we measured IgG/M/A, IgG, IgA, IgA isotypes (IgA1 and IgA2) and IgA1 subclasses (polymeric and monomeric IgA1) to anti-SSA/Ro52 in saliva supernatant of 34 pSS, 35 dry eyes and dry mouth (patients with Sicca) and 41 health controls.

Results: Saliva IgG/M/A, IgG, IgA, IgA isotypes and IgA1 subclasses to anti-SSA/Ro52 differed significantly between pSS, non-pSS Sicca and healthy subjects. Elevated monomeric IgA1 was observed in patients with non-pSS Sicca while elevated polymeric IgA1 (pIgA1) was observed in patients with pSS. Salivary polymeric but not monomeric IgA1 (mIgA1) isoform correlated with focus score (r2=0.467, p=0.001) CONCLUSIONS: Salivary anti-Ro52 polymeric IgA1 isoform is associated with glandular inflammation in pSS, while salivary monomeric IgA1 is associated with Sicca. Whether IgA1 isotope switching plays a role in the progression of the Sicca to pSS warrants further investigation.

Keywords: Autoantibodies; Autoimmune Diseases; Autoimmunity; Sjogren's Syndrome.

MeSH terms

Autoantibodies
Humans
Immunoglobulin A
Immunoglobulin G
Saliva*
Sjogren's Syndrome* / diagnosis

Substances

Immunoglobulin A
Autoantibodies
Immunoglobulin G

Abstract

MeSH terms

Substances

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