臨床検査55巻11号

2011年10月発行

特集 ここまでわかった自己免疫疾患 各論 4．そのほかの自己免疫疾患

2) 免疫性血小板減少症

著者： 桑名正隆¹

所属機関： ¹慶應義塾大学医学部リウマチ内科

ページ範囲：P.1212 - P.1219

免疫性血小板減少症(ITP)は，血小板膜糖蛋白に対する自己抗体により誘導される自己免疫疾患である．抗血小板抗体が結合した血小板がFcγ受容体を介して網内系マクロファージに捕捉，貪食される病態に加え，巨核球障害による血小板産生低下も関与する．網内系マクロファージ，自己反応性CD4⁺T細胞，B細胞による病的ループが成立すると抗血小板抗体産生が持続する．最近，制御性T細胞や抑制性Fcγ受容体を介した免疫制御の破綻が発症にかかわることも明らかにされた．新規治療標的が数多く同定され，自己免疫病態を是正する新規治療法の開発が期待される．

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