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Thiele, D.

Publications and source records attributed to Thiele, D..

3 recordsLinked to original sources

SATB1 maintains naive-like identity in antiviral CD8⁺ T cells by limiting chromatin remodelling at effector gene loci.

Optimal CD8+ T cell differentiation requires the engagement of transcriptional programs that drive effector phenotypes and function, whilst also shutting down transcriptional programs that maintain the naive state. While the distinct factors that underpin each state are well studied, the molecular mechanisms that control the switch from the naive to effector state are not fully understood. Utilising integrated analysis of single-cell genomic data, we identified CD8+ T cell effector transcriptional networks that are restrained in the naive state by the chromatin binding protein Special AT-rich sequence binding protein-1 (SATB1). Utilising a SATB1-Tg model, whereby activated CD8+ T cells are unable to down regulate SATB1 upon activation, we observed limited effector differentiation and an inability to engage effector programs in response to both primary and secondary influenza A virus infection. Mechanistically, SATB1 limited chromatin remodelling at key gene loci required for the full engagement of the CD8+ T cell effector program. Hence, SATB1 is a master gatekeeper that maintains the naive T cell state and whose downregulation is necessary to allow transition from a naive to effector state upon T cell activation. SATB1 modulation may provide new strategies for improving CD8+ T cell longevity and self-renewal capacity in different immunotherapeutic treatments.

immunology↗

Heterogeneous Tfh cell populations that develop during enteric helminth infection predict the quality of type 2 protective response

T follicular helper (Tfh) cells are an important component of the germinal centre (GC)-mediated humoral immunity. Yet, how regulation of Tfh- GC responses impacts on effective responses to helminth infection are poorly understood. Here we show that chronic helminth Trichuris muris infection fails to induce Tfh-GC B cell responses, with Tfh cells expressing T-bet and IFN-{gamma}. In contrast, Tfh cells that express GATA-3 and IL-4 dominate responses to an acute, resolving infection. Accordingly, heightened expression and increased chromatin accessibility of Th1- and Th2 cell-associated genes is observed in chronic and acute induced Tfh cells, respectively. However, both acute and chronic Tfh cell populations retained the capacity to produce IL-21 in spite of the Th-biased response. Blockade of Tfh-GC interactions impaired type 2 immunity, highlighting the protective role of GC-dependent Th2-like Tfh cell responses against helminths. Collectively, these results provide new insights into the protective roles of Tfh-GC responses and identify distinct transcriptional and epigenetic features of Tfh cells that emerge during resolving or chronic helminth infections. Author summaryAbout a quarter of the world population is afflicted with parasitic worm infection. Although deworming drugs can reduce the levels of the infection, they fail to prevent reinfections. Therefore, the most sustainable goal is to develop vaccines against human helminth parasites, which has been extremely challenging due to the lack of understanding of host-parasite interactions. While the protective roles of T helper 2 (Th2) cells are well established, the regulation of T follicular helper (Tfh) cells and their roles during helminth infection remain poorly defined. In this study, we describe the differential regulation of Tfh cell responses during chronic non-protective vs acute protective responses during helminth infection. We show that Tfh cells during chronic infection are rare and have strikingly different characteristics to acute-induced Tfh cells, which appear to be more like Th2 cells. Specifically, we show that blockade of Th2-like Tfh cell response during acute infection results in the host failing to expel the worms. Our study identifies that Tfh cell populations that emerge during chronic and acute infection are strikingly heterogeneous and critically important in mediating protective immune responses against helminths.

immunology↗

Neural harmonics reflect grammaticality

Can neural rhythms reflect purely internal syntactic processes in multi-word constructions? To test this controversial conjecture - relevant to language in particular and cognition more broadly - we recorded electroencephalographic and behavioural data as participants listened to isochronously presented sentences of varying in syntactic complexity. Each trial comprised ten concatenated sentences and was either fully grammatical (regular) or rendered ungrammatical via randomly distributed word order violations. We found that attending the regular repetition of abstract syntactic categories (phrases and sentences) generates neural rhythms whose harmonics are mathematically independent of word rate. This permits to clearly separate endogenous syntactic rhythms from exogenous speech rhythms. We demonstrate that endogenous but not exogenous rhythms predict participants grammaticality judgements, and allow for the neural decoding of regular vs. irregular trials. Neural harmonic series constitute a new form of behaviourally relevant evidence for syntactic competence.

neuroscience↗