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Biology subjects

Taber, A. K.

Publications and source records attributed to Taber, A. K..

3 recordsLinked to original sources

Tissue-specific adaptation of human T cells is preserved during tissue inflammation

T cells play an essential role in protecting tissues against pathogens and regulating tissue homeostasis. Previous studies highlight that T cells display tissue-specific phenotypic and functional properties, suggesting that T cells adapt to their local environment. Whether inflammation disrupts tissue-specific T cell adaptation remains poorly understood. To address this open question, we examined the T cell compartment - including conventional CD4 and CD8 T cells, regulatory T cells, {gamma}{delta} T cells, and MAIT cells - from healthy and inflamed human mucosal tissues. Using high-parameter spectral flow cytometry, we examined phenotype ex vivo and the functional capacity following stimulation, utilizing conventional gating and unsupervised clustering analysis approaches. Overall, we analyzed 65 tissue samples including mild, moderate, and severely inflamed oral gingiva, healthy and inflamed lung, along with healthy and inflamed tissue from the decidual-placental interface. Across these mucosal barrier tissues, we find that tissue location plays a dominant role in shaping the composition, phenotype, and functional capacity of the T cell compartment. Importantly, these tissue-specific adaptations were largely maintained during states of tissue inflammation. This included the ability to exert tissue repair functions, which was preserved across T cell subsets, even in severely inflamed tissues.

immunology↗

Converging cytokine and metabolite networks shape asymmetric T cell fate at the term human maternal-fetal interface

Placentation presents immune conflict between mother and fetus, yet in normal pregnancy maternal immunity against infection is maintained without expense to fetal tolerance. This is believed to result from adaptations at the maternal-fetal interface (MFI) which affect T cell programming, but the identities (i.e., memory subsets and antigenic specificities) of T cells and the signals that mediate T cell fates and functions at the MFI remain poorly understood. We found intact recruitment programs as well as pro-inflammatory cytokine networks that can act on maternal T cells in an antigen-independent manner. These inflammatory signals elicit T cell expression of co-stimulatory receptors necessary for tissue retention, which can be engaged by local macrophages. Although pro-inflammatory molecules elicit T cell effector functions, we show that additional cytokine (TGF-{beta}1) and metabolite (kynurenine) networks may converge to tune T cell function to those of sentinels. Together, we demonstrate an additional facet of fetal tolerance, wherein T cells are broadly recruited and restrained in an antigen-independent, cytokine/metabolite-dependent manner. These mechanisms provide insight into antigen-nonspecific T cell regulation, especially in tissue microenvironments where they are enriched.

immunology↗

Inflammatory signals are sufficient to elicit TOX expression in mouse and human CD8 T cells

T cell receptor (TCR) stimulation leads to expression of the transcription factor TOX. Prolonged TCR signaling, such as encountered during chronic infections or in tumors, leads to sustained TOX expression, which induces a state of exhaustion or dysfunction. While CD8 memory T cells (Tmem) in specific pathogen-free laboratory mice typically do not express TOX, functional human Tmem show heterogeneous TOX expression levels. Whether TCR-independent mechanisms can alter TOX expression in human and murine Tmem has not been defined. We report that human and mouse Tmem increase TOX expression following stimulation with inflammatory cytokines IL-12, IL-15, and IL-18. TOX and PD-1 expression patterns often appear to be directly correlated, however, we found that TOX is not necessary for cytokine-driven expression of PD-1. Together, these observations highlight that inflammation is sufficient to alter TOX and PD-1 expression and that the signals regulating TOX expression appear well conserved in human and murine Tmem.

immunology↗