The Heart and Antiphospholipid Antibodies in MRL-lpr/lpr Mice

Abstract

Our objective in this study was to determine possible associations between antiphospholipid antibodies (aPL) and histologically defined heart valve lesions in the MRL-lpr/lpr mouse, a suitable model for the antiphospholipid syndrome (APS). At monthly intervals, from 2 to 6 months of age, three MRL-lpr/lpr mice (two with anticardiolipin antibodies, one without) and two sex- and age-matched Balb/c mice (controls) were sacrificed for histological studies. Serum binding to phospholipids and DNA was studied at this time.

We found thickened heart valves in 68% of MRL-lpr/lpr mice and in 80% of Balb/c mice, and no association with any of the antibodies tested was found. No evidence of coronary vasculitis or thrombi was found in any of the mice studied. Platelet counts in MRL-lpr/lpr mice were significantly lower (640.530 ± 211.818 × 10⁶/ml) than in Balb/c mice (780.0 + 112.5 × 10⁶/ml) (P < 0.05), and no association was found between platelet counts and aPL. In this model of murine APS, aPL bear no importance in heart valve pathology.

Keywords

Antiphospholipid syndrome Animal models Anticardiolipin Lupus

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