Many alphaIIbbeta3 autoepitopes in chronic immune thrombocytopenic purpura are localized to alphaIIb between amino acids L1 and Q459.
Many alphaIIbbeta3 autoepitopes in chronic immune thrombocytopenic purpura are localized to alphaIIb between amino acids L1 and Q459.
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慢性免疫性血小板减少性紫癜中的许多 αIIbbeta3 自表位定位于氨基酸 L1 和 Q459 之间的 αIIb。
DOI:
10.1046/j.1365-2141.2002.03751.x
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发表时间:
2002
影响因子:
6.5
通讯作者:
Loftus,JosephC
中科院分区:
文献类型:
--
作者:
McMillan,Robert;Wang,Lei;Lopez-Dee,Jennifer;Jiu,Sandra;Loftus,JosephC
In chronic immune thrombocytopenic purpura (ITP), autoantibodies bind to platelet surface proteins, particularly αIIb, resulting in platelet destruction by the reticulo‐endothelial system. In order to better localize the autoepitopes on αIIb, we studied the binding of antibodies to Chinese hamster ovary (CHO) cells expressing either αIIbβ3or αIIb‐αvβ3chimaeras in which a segment of αIIb(either amino acids L1‐Q459, L1‐F223 or F223‐Q459) was substituted for that portion of αv. We evaluated platelet‐associated autoantibodies from 14 ITP patients with αIIb‐dependent antibodies. Ten of 14 bound to αIIb (L1‐Q459)‐αvβ3, showing that autoepitopes were often localized to this region of αIIb. In addition, each of the autoantibodies binding to αIIb (L1‐Q459)‐αvβ3, also bound to CHO cells expressing either αIIb(L1‐F223)‐αvβ3or αIIb(F223‐Q459)‐αvβ3). In two of the three eluates tested, > 95% of the autoantibody binding to αIIbcould be adsorbed using CHO cells expressing any of the three chimaeras, showing that the epitope(s) have contact points on either side of amino acid F223; in the third eluate, only a portion (∼40%) could be adsorbed by the chimaeric cell lines showing that, in this patient, an additional antibody was also present, directed to a site distal to amino acid Q459. The remaining four eluates bound to CHO cells expressing αIIbβ3but to none of the chimaeras, suggesting that these epitopes are also distal to amino acid Q459. We conclude that the binding of many anti‐αIIbβ3autoantibodies is dependent on the presence of αIIbamino acids L1‐Q459.
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影响因子:
6.5
作者:
Wertz,PW;Downing,DT
通讯作者:
Downing,DT
影响因子:
1.1
作者:
D. Downing;Zh Kranz;K. Murray
通讯作者:
K. Murray
DOI:
--
发表时间:
1986
期刊:
Differentiation; research in biological diversity
影响因子:
--
作者:
M. Brysk;S. Rajaraman;P. Penn;S. J. Chen
通讯作者:
S. J. Chen
DOI:
10.1016/0005-2736(88)90086-7
发表时间:
1988
期刊:
Biochimica et biophysica acta
影响因子:
--
作者:
Abraham,W;Wertz,PW;Downing,DT
通讯作者:
Downing,DT
DOI:
10.1016/0005-2736(86)90527-4
发表时间:
1986
期刊:
Biochimica et biophysica acta
影响因子:
--
作者:
Amselem,S;Barenholz,Y;Loyter,A;Nir,S;Lichtenberg,D
通讯作者:
Lichtenberg,D