EULAR Abstract 2 : Anti nucleosome Antibody in SLE

AB0826
COMPARISON OF ANTI-NUCLEOSOME AND ANTI-DSDNA ANTIBODIES AS LABORATORY MARKER FOR SYSTEMIC LUPUS ERYTHEMATOSUS.
H. Baharuddin 1,*, P. Sthaneshwar 2, T. E. Cheah 1, S. Sockalingam 1, A. A. Zain 1
1Medicine, 2Chemical Pathology, University of Malaya, Kuala Lumpur, Malaysia

Background:
There is evidence that nucleosomes are the driving immunogen and the in vivo target of lupus anti-dsDNA and anti-histone antibodies. ELISA can now be used to detect H1-stripped chromatin and nucleosome core particles.

Objectives:
To compare the levels of anti-nucleosome and anti-dsDNA antibodies in systemic lupus erythematosus (SLE) patients using the ELISA method and to determine their prevalence in patients with SLE, rheumatoid arthritis (RA), systemic sclerosis (SSc), mixed connective tissue disease (MCTD) and healthy controls.

Methods:
This is a cross sectional study of patients at University Malaya Medical Centre. The presence of anti-nucleosome antibodies and anti-dsDNA antibodies were determined by enzyme-linked immunosorbent assay (ELISA). Commercial ELISA AESKULISA Nucleo-h was used to detect anti-nucleosome antibodies and QUANTA Lite dsDNA ELISA was used to detect anti-dsDNA antibodies.

Results:
A total of 116 SLE patients, 67 patients with other connective tissue diseases and 50 healthy controls were included in the study. There was no statistical difference between the obtained area under the curve (AUC) for anti nucleosome and anti dsDNA antibodies. The sensitivity and specificity of anti-nucleosome antibodies was 51.7% and 94.9% respectively, compared with anti-dsDNA antibodies which was 52.6% and 89.7% respectively. There was no statistically significant differences. The prevalence of anti-nucleosome antibodies for SLE, RA, SS, SSc, IIF, MCTD and controls were 51.7%,0%, 5.9%, 16.7%, 0%, 20% and 0% respectively as compared with anti ds-DNA antibodies which were 52.6%, 10.5%, 23.5%, 8.3%, 25%, 26.7% and 0% respectively. There was no statistical differences noted.

Conclusions:
Anti nucleosome antibodies is comparable to anti-dsDNA antibodies as a laboratory marker of SLE.

References:
1. Amoura Z, Koutouzov S, Piette JC. The role of nucleosomes in lupus. Curr Opin Rheumatol 2000;12:369-73.
2. Burlingame RW. Recent advances in understanding the clinicl utility and underlying cause of antinucleosome (antichromatin) antibodies. Clinical and Applied Immunology Review4 2004;4:351-66
3. Gomez-Puerta JA, Burlingame RW, Cervera R. Anti-chromatin (anti-nucleosome) antibodies. Lupus 2006;15:408-11
4. Bruns A, Blass S, Hausdorf G, Burmester GR, Hiepe F. Nucleosomes are major t and b cell autoantigens in systemic lupus erythematosus. Arthritis Rheum 2000;43:2307-15.
5. Simon JA, Cabiedes J, Ortiz E, Alcocer-Varela J, Sanchez-Guerrero J. Anti-nucleosome antibodies in patients with systemic lupus erythematosus of recent onset. Potential utility as a diagnostic tool and disease activity marker. Rheumatology (Oxford) 2004;43:220-4.
6. Su Y, Jia RL, Han L, Li ZG. Role of anti-nucleosome antibody in the diagnosis of systemic lupus erythematosus. Clin Immunol 2007;122:115-20

Disclosure of Interest: None Declared