Publications by authors named "David E Hamm"

Recent insight into the mechanisms of induction of tissue-resident memory (T) CD8 T cells (CD8 T) enables the development of novel vaccine strategies against sexually transmitted infections. To maximize both systemic and genital intraepithelial CD8 T cells against vaccine Ags, we assessed combinations of i.m.

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Human regulatory dendritic cells (DCreg) were generated from CD14 immunobead-purified or elutriated monocytes in the presence of vitamin D3 and IL-10. They exhibited similar, low levels of costimulatory CD80 and CD86, but comparatively high levels of co-inhibitory programed death ligand-1 (PD-L1) and IL-10 production compared to control immature DC (iDC). Following Toll-like receptor 4 ligation, unlike control iDC, DCreg resisted phenotypic and functional maturation and further upregulated PD-L1:CD86 expression.

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Islet-reactive memory CD4(+) T cells are an essential feature of type 1 diabetes (T1D) as they are involved in both spontaneous disease and in its recurrence after islet transplantation. Expansion and enrichment of memory T cells have also been shown in the peripheral blood of diabetic patients. Here, using high-throughput sequencing, we investigated the clonal diversity of the TCRβ repertoire of memory CD4(+) T cells in the pancreatic lymph nodes (PaLN) of non-obese diabetic (NOD) mice and examined their clonal overlap with islet-infiltrating memory CD4T cells.

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Acute respiratory distress syndrome (ARDS) is a devastating disorder characterized by increased alveolar permeability with no effective treatment beyond supportive care. Current mechanisms underlying ARDS focus on alveolar endothelial and epithelial injury caused by products of innate immune cells and platelets. However, the role of adaptive immune cells in ARDS remains largely unknown.

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T-cell large granular lymphocytic leukemia and chronic lymphoproliferative disorder of natural killer cells are intriguing entities between benign and malignant lymphoproliferation. The molecular pathogenesis has partly been uncovered by the recent discovery of somatic activating STAT3 and STAT5b mutations. Here we show that 43% (75/174) of patients with T-cell large granular lymphocytic leukemia and 18% (7/39) with chronic lymphoproliferative disorder of natural killer cells harbor STAT3 mutations when analyzed by quantitative deep amplicon sequencing.

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The TCR:CD3 complex transduces signals that are critical for optimal T cell development and adaptive immunity. In resting T cells, the CD3ε cytoplasmic tail associates with the plasma membrane via a proximal basic-rich stretch (BRS). In this study, we show that mice lacking a functional CD3ε-BRS exhibited substantial reductions in thymic cellularity and limited CD4- CD8- double-negative (DN) 3 to DN4 thymocyte transition, because of enhanced DN4 TCR signaling resulting in increased cell death and TCR downregulation in all subsequent populations.

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Autoreactive memory CD4(+) T cells play a critical role in the development of type 1 diabetes, but it is not yet known how the clonotypic composition and TCRβ repertoire of the memory CD4(+) T cell compartment changes during the transition from prediabetes to diabetes. In this study, we used high-throughput sequencing to analyze the TCRβ repertoire of sorted islet-infiltrating memory CD4(+)CD44(high) T cells in 10-week-old prediabetic and recently diabetic NOD mice. We show that most clonotypes of islet-infiltrating CD4(+)CD44(high) T cells were rare, but high-frequency clonotypes were significantly more common in diabetic than in prediabetic mice.

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