Serum Biomarker Panels for Lupus May Aid Diagnosis

By Reuters Staff

January 13, 2020

NEW YORK (Reuters Health) - New serum biomarker panels show promise for diagnosing systemic lupus erythematosus (SLE) and for the differential diagnosis of other major rheumatic immune diseases, report researchers from China.

"Clinical diagnosis of SLE is currently challenging due to its heterogeneity. Many autoantibodies are associated with SLE and are considered potential diagnostic markers, but systematic screening and validation of such autoantibodies is lacking," Dr. Dong-Qing Ye of Anhui Medical University and colleagues note in Rheumatology.

To identify candidate SLE-related autoantibodies, they analyzed sera from 15 patients with SLE and five healthy volunteers using human proteome microarrays. They validated their results in 107 SLE patients, 94 healthy volunteers and 60 disease controls using focused arrays made up of autoantigens corresponding to the identified candidate antibodies.

The researchers identified 31 autoantibodies that were expressed at significantly higher levels in the SLE group than in healthy volunteers; 11 autoantibodies with significantly higher expression in the SLE group than in disease controls; and 18 when the healthy volunteers plus disease controls were combined and compared with the SLE group.

Many of these differentially expressed autoantibodies were previously unreported.

The researchers say an optimized panel of three autoantibodies (anti-RPLP2, anti-SNRPC and anti-PARP1) had an area under the curve (AUC) of 0.973 for SLE diagnosis, while a panel of four biomarkers (anti-RPLP2, anti-PARP1, anti-MAK16 and anti- RPL7A) had an AUC of 0.911 for the differential diagnosis of SLE.

The researchers also observed some correlations between the autoantibodies identified and clinical characteristics of SLE patients, such as disease activity with the level of anti-PARP1 and rash with the level of anti-RPLP2, anti-MAK16 and anti- RPL7A.

"Further validation and application of the combined biomarker panels in clinical practice is expected," they conclude.

The study had no commercial funding and the authors made no relevant disclosures.

Dr. Ye did not respond to a request for comment by press time.

SOURCE: Rheumatology, online January 3, 2020.