Anti-beta 2 glycoprotein I antibodies in centenarians.
BACKGROUND
Non-organ-specific autoantibodies are present in centenarians without evidence of autoimmune diseases but conflicting or no data on anti-phospholipid and anti-phospholipid binding proteins were reported.


OBJECTIVE
To investigate the presence and antigen specificity of anti-phospholipid and anti-phospholipid binding proteins in centenarians.


METHODS
Seventy-seven centenarians, 70 adult controls, 65 unselected elderly subjects, and 38 old SENIEUR volunteers were investigated. Anti-cardiolipin, anti-human beta 2 glycoprotein I, and lupus anticoagulant were detected. Antigen specificity was assayed against plates coated with anionic, neutral and cationic phospholipids and beta 2 glycoprotein I-dependence was also evaluated.


RESULTS
54.3% of the centenarians were positive for IgG and 8.6% for IgM anti-beta 2 glycoprotein I antibodies, while only 20.7% centenarians were positive for anti-cardiolipin IgG and 2.59% for IgM; none resulted positive for lupus anticoagulant. Anti-cardiolipin positive sera cross-reacted with negatively charged phospholipids and displayed decreased binding to serum-free cardiolipin-coated plates that was restored by human beta 2 glycoprotein I or fetal calf serum.


CONCLUSIONS
Centenarians display high reactivity against human beta 2 glycoprotein I but low binding to the bovine molecule in the anti-cardiolipin assay. In spite of the presence of antibodies comparable to those found in patients with the anti-phospholipid syndrome, no vascular events were reported suggesting the presence of unknown protective factors and/or the lack of triggering factors.
Meroni
P L
PL
Allergy, Clinical Immunology and Rheumatology Unit, Department of Internal Medicine, University of Milan, IRCCS Istituto Auxologico Italiano, Via G. Spagnoletto 3, 20149 Milan, Italy. pierluigi.meroni@unimi.it
Mari
D
D
Monti
D
D
Coppola
R
R
Capri
M
M
Salvioli
S
S
Tincani
A
A
Gerli
R
R
Franceschi
C
C
D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000276:immunology*; D001323:Autoantibodies / Q000097:blood*; D002308:Cardiolipins / Q000276:immunology; D000939:Epitopes; D005260:Female; D006023:Glycoproteins / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D016682:Lupus Coagulation Inhibitor / Q000097:blood; D008297:Male; D053482:beta 2-Glycoprotein I
D001323:Autoantibodies; D002308:Cardiolipins; D000939:Epitopes; D006023:Glycoproteins; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D016682:Lupus Coagulation Inhibitor; D053482:beta 2-Glycoprotein I