免疫チェックポイント受容体であるPD-1(Programmed death receptor-1)は、腫瘍環境で過剰発現しており、T細胞の疲弊化が促進されるため、抗腫瘍免疫応答が減弱します。PD-1の阻害は細胞傷害性T細胞 の免疫機能を賦活化させます。
発現および生理的な機能
PD-1は細胞傷害性T細胞上に発現する免疫チェックポイント受容体です。 PD-1のリガンドには、PD-L1(Programmed death ligand 1)およびPD-L2(Programmed death ligand 2)の2つが存在します1-3。 - これらのリガンドは、T細胞の活性を阻害する点において、機能が重複しています1,2。
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