Schaller Tschan, Monica; Vogel, Monique; Kentouche, Karim; Lämmle, Bernhard; Kremer Hovinga, Johanna Anna (2014). The splenic autoimmune response to ADAMTS13 in thrombotic thrombocytopenic purpura contains recurrent antigen-binding CDR3 motifs. Blood, 124(23), pp. 3469-3479. American Society of Hematology 10.1182/blood-2014-04-561142
Text
2014_Blood_M.Schaller_The plenic autoimmune response.full.pdf - Published Version Restricted to registered users only Available under License Publisher holds Copyright. Download (1MB) |
Acquired thrombotic thrombocytopenic purpura (TTP) is the consequence of a severe ADAMTS13 deficiency resulting from autoantibodies inhibiting ADAMTS13 or accelerating its clearance. Despite the success of plasma exchange the risk of relapse is high. From 2 patients (A and B), splenectomized for recurrent episodes of acquired TTP, the splenic B-cell response against ADAMTS13 was characterized through generation of human monoclonal anti-ADAMTS13 autoantibodies (mAbs) by cloning an immunoglobulin G (IgG)4κ- and IgG4λ-Fab library using phage display technology and by Epstein-Barr virus transformation of switched memory B cells (CD19+/CD27+/IgG+). Sequence analysis of the anti-ADAMTS13 IgGs of both patients revealed that the VH gene use was limited in our patients to VH1-3 (55%), VH1-69 (17%), VH3-30 (7%), and VH4-28 (21%) and contained 8 unique and thus far not reported heavy-chain complementarity determining region 3 motifs, of which 4 were shared by the 2 patients. The discovery of several highly similar anti-ADAMTS13 autoantibodies in 2 unrelated TTP patients suggests that the autoimmune response is antigen driven, because the probability that such similar immunoglobulin rearrangements happen by chance is very low (< 10(-9)).