臨床検査55巻1号

2011年01月発行

今月の主題 -ミクログロブリン－その多様な病因，病態と検査アプローチ 総論

β₂-ミクログロブリンの構造，機能と病態検査

著者： 伊藤喜久¹

所属機関： ¹旭川医科大学臨床検査医学

ページ範囲：P.11 - P.18

β₂-ミクログロブリン(β₂-m)は患者尿から生成された分子量11,800の低分子蛋白質である．HLA class Ⅰ抗原のL鎖として自己と非自己の認識に不可欠な構造蛋白で，関連抗原の1つであるneonatal Fc receptorではIgG，アルブミンの寿命延長，機能の維持に重要な役割を果たす．さらに病的状態におけるβ₂-mは腫瘍増殖，遠隔転移因子など多彩な機能を発揮する．βシート構造特性に関連して長期血液透析アミロイドーシスの病因物質でもある．種々の疾患での病態機序が明らかにされ早期発見，予防，治療を目的に血清，尿測定がさらに一層拡大してきている．β₂-mの基礎，臨床研究の進歩をレビューし，病態検査の視点から新たな動向を探索した．

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