Arthritis & Rheumatism, Volume 62,
November 2010 Abstract Supplement

Abstracts of the American College of
Rheumatology/Association of Rheumatology Health Professionals
Annual Scientific Meeting
Atlanta, Georgia November 6-11, 2010.


Anti-2 Glycoprotein I Antibodies from Leprosy Patients Do Not Show Thrombogenic Effects in an In Vivo Animal Model.

Forastiero2,  Ricardo, Martinuzzo2,  Marta, Vega-Ostertag2,  Mariano, de Larranaga2,  Gabriela, Pierangeli1,  Silvia S.

Univ of TX Medical Branch, Galveston, TX
Universidad Favaloro, Buenos Aires, Argentina

Background:

The APS-associated aPL are autoantibodies directed against b2GPI and prothrombin. Patients with leprosy present high frequency of IgM aPL that bind b2GPI, but they do not develop thrombosis. Anti-b2GPI from APS mainly bind to domain I of b2GPI while in leprosy are directed against domain V. There is convincing evidence that aPL/anti-b2GPI from APS are pathogenic in vivo and in vitro.

Objective:

to investigate the thrombogenic and pro-inflammatory effects of aPL from leprosy and to compare with aPL from APS.

Methods:

Sera from 6 patients with APS and 6 with leprosy were used as the source of IgM. All APS and 5 leprosy patients had strong LA activity, and high titers of IgM aCL/anti-b2GPI. The remaining leprosy patient was aPL negative (control). We treated CD1 mice, in groups of 5, at 0 hours and 48 hours later with IgM aPL/anti-b2GPI isolated from patients with leprosy (IgM-leprosy) or APS (IgM-APS) or with IgM from 2 healthy controls (IgM-NHS) or 1 leprosy aPL negative control. Seventy-two hours after the first injection, the adhesion of leukocytes (#WBC) to endothelial cells (EC) in cremaster muscle (as an indication of EC activation in vivo), as well as the size of an induced thrombus in the femoral vein of the mice were examined.

Results:

IgM-APS significantly increased the thrombus size (in mum2) when compared to IgM-NHS or IgM-leprosy treated mice (p<0.001). There was no difference in mice injected with IgM-leprosy, IgM-NHS or IgM-leprosy control. IgM-APS increased the #WBC adhering to EC, when compared to IgM-NHS or IgM-leprosy (p<0.001).

 IgM-APSIgM-leprosyIgM-NHSIgM-leprosy control
Mean thrombus size44461378748851
#WBC5.1 ± 2.22.0 ± 1.03.5 ± 1.61.3 ± 0.5

Conclusions:

Our data shown that aPL/anti-b2GPI from leprosy patients have not thrombogenic and pro-inflammatory effects in vivo when compared with aPL derived from APS.

To cite this abstract, please use the following information:
Forastiero, Ricardo, Martinuzzo, Marta, Vega-Ostertag, Mariano, de Larranaga, Gabriela, Pierangeli, Silvia S.; Anti-2 Glycoprotein I Antibodies from Leprosy Patients Do Not Show Thrombogenic Effects in an In Vivo Animal Model. [abstract]. Arthritis Rheum 2010;62 Suppl 10 :3
DOI: 10.1002/art.27773

Abstract Supplement

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