Quantitation and IgG subclass distribution of antichromatin autoantibodies in SLE mice.
Antibodies to a native chromatin preparation were found in most mice suffering from spontaneous SLE. All MRL/Mp-lpr/lpr (MRL/lpr) sera tested (more than 500) contained antibodies to chromatin and antichromatin levels increased with age. Approximately 50% of the IgG antichromatin antibody in the MRL/lpr sera was of the IgG2a subclass, 30% IgG2b, 10% IgG1, and 10% IgG3. Interestingly, the relative restriction of antichromatin autoantibodies to the IgG2a subclass was apparent in MRL/lpr mice as young as 1 month, well before the onset of lymphadenopathy. Antichromatin autoantibodies were also detectable in sera from MRL/Mp- +/+ (MRL/+), NZB, (NZB x NZW)F1 (B x W), and BXSB mice, but were not found in sera from normal mice. A similar subclass distribution skewed toward IgG2a was seen for MRL/+, B x W, and NZB mice. These results indicate that the spontaneous autoantibody directed against chromatin is a good marker for murine SLE, and is predominantly of the IgG2a subclass.
Fisher
C L
CL
Department of Biochemistry and Nutrition, University of North Carolina, Chapel Hill 27514.
Eisenberg
R A
RA
Cohen
P L
PL
D000367:Age Factors; D000818:Animals; D001323:Autoantibodies / Q000276:immunology*; D002843:Chromatin / Q000276:immunology*; D007074:Immunoglobulin G / Q000276:immunology*; D007132:Immunoglobulin Isotypes / Q000276:immunology*; D008180:Lupus Erythematosus, Systemic / Q000276:immunology*; D051379:Mice; D008817:Mice, Mutant Strains / Q000276:immunology
D001323:Autoantibodies; D002843:Chromatin; D007074:Immunoglobulin G; D007132:Immunoglobulin Isotypes