AUTHOR=Bu Siyuan , Liu Min , Yang Lu , Lee Pamela , Miller Heather , Park Chan-Sik , Byazrova Maria , Filatov Alexander , Benlagha Kamel , Gaber Timo , Buttgereit Frank , Gong Quan , Zhai Zhimin , Liu Chaohong TITLE=The function of T cells in immune thrombocytopenia JOURNAL=Frontiers in Immunology VOLUME=Volume 16 - 2025 YEAR=2025 URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2025.1499014 DOI=10.3389/fimmu.2025.1499014 ISSN=1664-3224 ABSTRACT=Immune thrombocytopenia (ITP) is an autoimmune disease, characterized by increased bleeding due to a reduced platelet count. The pathogenesis of ITP is very complex and involves autoantibody production and T-cell-mediated immune abnormalities. An imbalance of effector and regulatory CD4+ T cells and the breach of tolerance primarily cause ITP, leading to the dysfunctional development of autoreactive Th cells (including Th1, Th2, and Th17 cells) and Tregs. The loss of auto-platelet antigen tolerance in ITP results in autoantibody- and cytotoxic T-cell-mediated platelet clearance. T-cell-related genetic risk factors significantly influence the development and progression of this disease. New therapies targeting T cells have emerged as potentially effective cures for this disease. This review summarizes the role of T cells in ITP.