Aiolos represses CD4+ T cell cytotoxic programming via reciprocal regulation of TFH transcription factors and IL-2 sensitivity
Kaitlin A. Read, Devin M. Jones, Srijana Pokhrel, Emily D. S. Hales, Aditi Varkey, Jasmine A. Tuazon, Caprice D. Eisele, Omar Abdouni, Abbey A. Saadey, Melissa R. Leonard, Robert T. Warren, Michael D. Powell, Jeremy M. Boss, Emily A. Hemann, Jacob S. Yount, Gang Xin, Hazem E. Ghoneim, Chan‐Wang Jerry Lio, Aharon G. Freud, Patrick L. Collins, Kenneth J. Oestreich
Abstract
Abstract During intracellular infection, T follicular helper (T FH ) and T helper 1 (T H 1) cells promote humoral and cell-mediated responses, respectively. Another subset, CD4-cytotoxic T lymphocytes (CD4-CTLs), eliminate infected cells via functions typically associated with CD8 + T cells. The mechanisms underlying differentiation of these populations are incompletely understood. Here, we identify the transcription factor Aiolos as a reciprocal regulator of T FH and CD4-CTL programming. We find that Aiolos deficiency results in downregulation of key T FH transcription factors, and consequently reduced T FH differentiation and antibody production, during influenza virus infection. Conversely, CD4-CTL programming is elevated, including enhanced Eomes and cytolytic molecule expression. We further demonstrate that Aiolos deficiency allows for enhanced IL-2 sensitivity and increased STAT5 association with CD4-CTL gene targets, including Eomes, effector molecules, and IL2Ra. Thus, our collective findings identify Aiolos as a pivotal regulator of CD4-CTL and T FH programming and highlight its potential as a target for manipulating CD4 + T cell responses.