Transfer of experimental antiphospholipid syndrome by bone marrow cell transplantation the importance of the t cell

Objective. To investigate the potential of bone marrow cells from mice with primary antiphospholipid syndrome (APS) to transfer the disease to naive mice, and to determine the importance of the role of T cells in the APS. Methods. Experimental primary APS was induced in naive mice following active immunization with anticardiolipin (aCL) monoclonal antibody (MAb). Whole‐population or T cell–depleted bone marrow cells from mice with experimental primary APS were infused into total body–irradiated naive BALB/c recipients. Results. Bone marrow cells (in the presence of T cells) had the potential to induce experimental APS in naive mice, which resulted in high serum titers of aCL, antiphosphatidylserine, and antiphosphatidylinositol antibodies; an increased number of antibody‐forming cells specific for each of the above phospholipids; a positive lymph node cell proliferative response to aCL MAb; and clinical features of primary APS, including thrombocytopenia, prolonged activated partial thromboplastin time (indicating the presence of lupus anticoagulant), and a high frequency of fetal resorptions (the equivalent of human fetal loss). T cell–depleted bone marrow cells did not transfer the disease. Conclusion. This study demonstrates the important role of T cells in the development and transfer of experimental primary APS and raises the possibility of T cell manipulations in treatments to prevent this condition.