Atherosclerosis-Driven Treg Plasticity Results in Formation of a Dysfunctional Subset of Plastic IFN gamma(+) Th1/Tregs
CIRCULATION RESEARCH
Authors: Butcher, Matthew J.; Filipowicz, Adam R.; Waseem, Tayab C.; McGary, Christopher M.; Crow, Kevin J.; Magilnick, Nathaniel; Boldin, Mark; Lundberg, Patric S.; Galkina, Elena V.
Abstract
Rationale: Forkhead box P3(+) T regulatory cells (Tregs) are key players in maintaining immune homeostasis. Evidence suggests that Tregs respond to environmental cues to permit or suppress inflammation. In atherosclerosis, Th1-driven inflammation affects Treg homeostasis, but the mechanisms governing this phenomenon are unclear. Objective: Here, we address whether atherosclerosis impacts Treg plasticity and functionality in Apoe(-/-) mice, and what effect Treg plasticity might have on the pathology of atherosclerosis. Methods and Results: We demonstrate that atherosclerosis promotes Treg plasticity, resulting in the reduction of CXCR3(+) Tregs and the accumulation of an intermediate Th1-like interferon (IFN)-gamma(+) CCR5(+) Treg subset (Th1/Tregs) within the aorta. Importantly, Th1/Tregs arise in atherosclerosis from bona fide Tregs, rather than from T-effector cells. We show that Th1/Tregs recovered from atherosclerotic mice are dysfunctional in suppression assays. Using an adoptive transfer system and plasticity-prone Mir146a-/-Tregs, we demonstrate that elevated IFN gamma(+)Mir146a(-/-)Th1/Tregs are unable to adequately reduce atherosclerosis, arterial Th1, or macrophage content within Apoe(-/-) mice, in comparison to Mir146a(+/+) Tregs. Finally, via single-cell RNA-sequencing and real-time-polymerase chain reaction, we show that Th1/Tregs possess a unique transcriptional phenotype characterized by coexpression of Treg and Th1 lineage genes and a downregulation of Treg-related genes, including Ikzf2, Ikzf4, Tigit, Lilrb4, and Il10. In addition, an ingenuity pathway analysis further implicates IFN gamma, IFN alpha, interleukin-2, interleukin-7, CTLA-4 (cytotoxic T-lymphocyte-associated protein 4), T-cell receptor, and Csnk2b-related pathways in regulating Treg plasticity. Conclusions: Atherosclerosis drives Treg plasticity, resulting in the accumulation of dysfunctional IFN gamma(+) Th1/Tregs that may permit further arterial inflammation and atherogenesis.
Molecular heterogeneity in peripheral T-cell lymphoma, not otherwise specified revealed by comprehensive genetic profiling
LEUKEMIA
Authors: Watatani, Yosaku; Sato, Yasuharu; Miyoshi, Hiroaki; Sakamoto, Kana; Nishida, Kenji; Gion, Yuka; Nagata, Yasunobu; Shiraishi, Yuichi; Chiba, Kenichi; Tanaka, Hiroko; Zhao, Lanying; Ochi, Yotaro; Takeuchi, Yasuhide; Takeda, June; Ueno, Hiroo; Kogure, Yasunori; Shiozawa, Yusuke; Kakiuchi, Nobuyuki; Yoshizato, Tetsuichi; Nakagawa, Masahiro M.; Nanya, Yasuhito; Yoshida, Kenichi; Makishima, Hideki; Sanada, Masashi; Sakata-Yanagimoto, Mamiko; Chiba, Shigeru; Matsuoka, Ryota; Noguchi, Masayuki; Hiramoto, Nobuhiro; Ishikawa, Takayuki; Kitagawa, Junichi; Nakamura, Nobuhiko; Tsurumi, Hisashi; Miyazaki, Tatsuhiko; Kito, Yusuke; Miyano, Satoru; Shimoda, Kazuya; Takeuchi, Kengo; Ohshima, Koichi; Yoshino, Tadashi; Ogawa, Seishi; Kataoka, Keisuke
Abstract
Peripheral T-cell lymphoma, not otherwise specified (PTCL, NOS) is a diagnosis of exclusion, being the most common entity in mature T-cell neoplasms, and its molecular pathogenesis remains significantly understudied. Here, combining whole-exome and targeted-capture sequencing, gene-expression profiling, and immunohistochemical analysis of tumor samples from 133 cases, we have delineated the entire landscape of somatic alterations, and discovered frequently affected driver pathways in PTCL, NOS, with and without a T-follicular helper (TFH) cell phenotype. In addition to previously reported mutational targets, we identified a number of novel recurrently altered genes, such as KMT2C, SETD1B, YTHDF2, and PDCD1. We integrated these genetic drivers using hierarchical clustering and identified a previously undescribed molecular subtype characterized by TP53 and/or CDKN2A mutations and deletions in non-TFH PTCL, NOS. This subtype exhibited different prognosis and unique genetic features associated with extensive chromosomal instability, which preferentially affected molecules involved in immune escape and transcriptional regulation, such as HLA-A/B and IKZF2. Taken together, our findings provide novel insights into the molecular pathogenesis of PTCL, NOS by highlighting their genetic heterogeneity. These results should help to devise a novel molecular classification of PTCLs and to exploit a new therapeutic strategy for this group of aggressive malignancies.