Antibodies elicited in response to EBNA-1 may cross-react with dsDNA.
BACKGROUND
Several genetic and environmental factors have been linked to Systemic Lupus Erythematosus (SLE). One environmental trigger that has a strong association with SLE is the Epstein Barr Virus (EBV). Our laboratory previously demonstrated that BALB/c mice expressing the complete EBNA-1 protein can develop antibodies to double stranded DNA (dsDNA). The present study was undertaken to understand why anti-dsDNA antibodies arise during the immune response to EBNA-1.


RESULTS
In this study, we demonstrated that mouse antibodies elicited in response to EBNA-1 cross-react with dsDNA. First, we showed that adsorption of sera reactive with EBNA-1 and dsDNA, on dsDNA cellulose columns, diminished reactivity with EBNA-1. Next, we generated monoclonal antibodies (MAbs) to EBNA-1 and showed, by several methods, that they also reacted with dsDNA. Examination of two cross-reactive MAbs--3D4, generated in this laboratory, and 0211, a commercial MAb--revealed that 3D4 recognizes the carboxyl region of EBNA-1, while 0211 recognizes both the amino and carboxyl regions. In addition, 0211 binds moderately well to the ribonucleoprotein, Sm, which has been reported by others to elicit a cross-reactive response with EBNA-1, while 3D4 binds only weakly to Sm. This suggests that the epitope in the carboxyl region may be more important for cross-reactivity with dsDNA while the epitope in the amino region may be more important for cross-reactivity with Sm.


CONCLUSIONS
In conclusion, our results demonstrate that antibodies to the EBNA-1 protein cross-react with dsDNA. This study is significant because it demonstrates a direct link between the viral antigen and the development of anti-dsDNA antibodies, which are the hallmark of SLE. Furthermore, it illustrates the crucial need to identify the epitopes in EBNA-1 responsible for this cross-reactivity so that therapeutic strategies can be designed to mask these regions from the immune system following EBV exposure.
Department of Chemistry, The City College of New York and the Graduate Center of the City University of New York, New York, New York, United States of America.
Pragya
P
Yadav
Hoa
H
Tran
Roland
R
Ebegbe
Paul
P
Gottlieb
Hui
H
Wei
Rita H
RH
Lewis
Alice
A
Mumbey-Wafula
Atira
A
Kaplan
Elina
E
Kholdarova
Linda
L
Spatz
D000818:Animals; D000911:Antibodies, Monoclonal / Q000096:biosynthesis; D000914:Antibodies, Viral / Q000276:immunology*; D003429:Cross Reactions / Q000276:immunology*; D004247:DNA / Q000276:immunology*; D000939:Epitopes; D019309:Epstein-Barr Virus Nuclear Antigens / Q000276:immunology*; D008180:Lupus Erythematosus, Systemic / Q000209:etiology / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C
D000911:Antibodies, Monoclonal; D000914:Antibodies, Viral; D000939:Epitopes; D019309:Epstein-Barr Virus Nuclear Antigens; D004247:DNA; C417029:EBV-encoded nuclear antigen 1
Cell. 1996 Mar 8;84(5):791-800
8625416
Clin Dev Immunol. 2008;2008:683489
18682819
J Immunol. 2002 Mar 15;168(6):3072-8
11884481
J Immunol. 1995 Feb 15;154(4):1987-94
7836777
J Autoimmun. 2001 Jun;16(4):479-84
11437497
Arthritis Rheum. 2001 May;44(5):1122-6
11352244
Int Immunol. 2001 Feb;13(2):223-32
11157855
Ann N Y Acad Sci. 1997 Apr 5;815:124-7
9186649
J Virol. 1996 Feb;70(2):1228-31
8551585
J Clin Invest. 1997 Dec 15;100(12):3019-26
9399948
J Clin Invest. 1998 Aug 15;102(4):754-63
9710444
Nature. 1995 Jun 22;375(6533):685-8
7540727
J Autoimmun. 2004 Sep;23(2):127-40
15324931
Nat Med. 2001 Nov;7(11):1189-93
11689882
J Biol Chem. 1991 Apr 25;266(12):7819-26
1850421
Arthritis Rheum. 2006 Jan;54(1):360-8
16385527
J Immunol. 2010 Jan 15;184(2):1085-91
20007529
J Immunol. 1994 Oct 15;153(8):3551-6
7930577
Virology. 2002 Apr 10;295(2):266-71
12033785
Mol Immunol. 2006 Apr;43(11):1776-90
16430962
Proc Natl Acad Sci U S A. 1997 Mar 4;94(5):1955-60
9050886
Arthritis Rheum. 1990 Jul;33(7):993-1000
2164400
FEBS Lett. 1990 Feb 26;261(2):464-7
2178981
Autoimmun Rev. 2009 Feb;8(4):337-42
19167523
J Autoimmun. 2008 Dec;31(4):362-71
18849143
J Autoimmun. 2009 Nov-Dec;33(3-4):270-4
19398190
J Autoimmun. 1999 Dec;13(4):423-8
10585758
Eur J Immunol. 1993 May;23(5):1146-52
8386666
J Immunol. 1995 Jul 15;155(2):967-73
7608572
Autoimmunity. 1990;6(4):249-56
2104176
J Protein Chem. 1998 Oct;17(7):599-606
9853674
J Autoimmun. 1994 Apr;7(2):179-91
7518683
J Virol. 2000 Jun;74(11):4939-48
10799567
Clin Exp Immunol. 1986 Nov;66(2):255-61
3102132
Clin Immunol. 2001 Feb;98(2):293-300
11161987