First Author | Zheng Y | Year | 2013 |
Journal | Blood | Volume | 121 |
Issue | 17 | Pages | 3484-92 |
PubMed ID | 23460609 | Mgi Jnum | J:197558 |
Mgi Id | MGI:5493369 | Doi | 10.1182/blood-2013-01-477091 |
Citation | Zheng Y, et al. (2013) Critical role for mouse marginal zone B cells in PF4/heparin antibody production. Blood 121(17):3484-92 |
abstractText | Heparin-induced thrombocytopenia (HIT) is an immune-mediated disorder that can cause fatal arterial or venous thrombosis/thromboembolism. Immune complexes consisting of platelet factor 4 (PF4), heparin, and PF4/heparin-reactive antibodies are central to the pathogenesis of HIT. However, the B-cell origin of HIT antibody production is not known. Here, we show that anti-PF4/heparin antibodies are readily generated in wild-type mice on challenge with PF4/heparin complexes, and that antibody production is severely impaired in B-cell-specific Notch2-deficient mice that lack marginal zone (MZ) B cells. As expected, Notch2-deficient mice responded normally to challenge with T-cell-dependent antigen nitrophenyl-chicken gamma globulin but not to the T-cell-independent antigen trinitrophenyl-Ficoll. In addition, wild-type, but not Notch2-deficient, B cells plus B-cell-depleted wild-type splenocytes adoptively transferred into B-cell-deficient muMT mice responded to PF4/heparin complex challenge. PF4/heparin-specific antibodies produced by wild-type mice were IgG2b and IgG3 isotypes. An in vitro class-switching assay showed that MZ B cells were capable of producing antibodies of IgG2b and IgG3 isotypes. Lastly, MZ, but not follicular, B cells adoptively transferred into B-cell-deficient muMT mice responded to PF4/heparin complex challenge by producing PF4/heparin-specific antibodies of IgG2b and IgG3 isotypes. Taken together, these data demonstrate that MZ B cells are critical for PF4/heparin-specific antibody production. |