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Mathews, C. E.

Publications and source records attributed to Mathews, C. E..

21 records · Page 2Linked to original sources

High-Yield Monocyte, Macrophage, and Dendritic Cell Differentiation from Induced Pluripotent Stem Cells

Differentiation of induced pluripotent stem cells (iPSC) into monocytes, monocyte-derived macrophages (MDM), and monocyte-derived dendritic cells (moDC) represents a powerful tool for studying human innate immunology and developing novel iPSC-derived immune therapies. Challenges include inefficiencies in iPSC-derived cell cultures, labor-intensive culture conditions, low purity of desired cell types, and feeder cell requirements. Here, a highly efficient method for differentiating monocytes, MDMs, and moDCs that overcomes these challenges is described. The process utilizes commercially-available materials to derive CD34+ progenitor cells that are apically released from a hemogenic endothelium. Subsequently, the hemogenic endothelium gives rise to highly pure (>95%), CD34-CD14+ monocytes in 19-23 days and yields 13.5-fold more monocytes by day 35 when compared to previous methods. These iPSC-monocytes are analogous to human blood-derived monocytes and readily differentiate into MDM and moDC. The efficient workflow and increase in monocyte output heightens feasibility for high throughput studies and enables clinical-scale iPSC-derived manufacturing processes.

immunology↗

NADPH Oxidase 2 Derived Reactive Oxygen Species Promote CD8+ T cell Effector Function

Oxidants participate in lymphocyte activation and function. We previously demonstrated that eliminating the activity of NADPH oxidase 2 (NOX2) significantly impaired the effectiveness of autoreactive CD8+ cytotoxic T lymphocytes (CTL). However, the molecular mechanisms impacting CTL function remain unknown. Here, we studied the role of NOX2 in both non-obese diabetic (NOD) mouse and human CTL function. Genetic ablation or chemical inhibition of NOX2 in CTL significantly suppressed activation-induced expression of the transcription factor T-bet, the master transcription factor of the Tc1 cell lineage, and T-bet target effectors genes such as IFN{gamma} and granzyme B. Inhibition of NOX2 in both human and mouse CTL prevented target cell lysis. We identified that superoxide generated by NOX2 must be converted into hydrogen peroxide to transduce the redox signal in CTL. Further, we show that NOX2-generated oxidants deactivate the Tumor Suppressor Complex leading to mTOR complex 1 activation and CTL effector function. These results indicate that NOX2 plays a non-redundant role in T cell receptor-mediated CTL effector function.

immunology↗

Human CD8+ T-cells Require Glycolysis to Elicit Effector Function

Targeting human T-cell metabolism for modulating immune function requires an understanding of macronutrient utilization. Using metabolic inhibition during activation of human naive CD8+ T-cells, we demonstrate blocking glycolysis or mitochondrial respiration prevents T-cell proliferation. However, after activation and differentiation, the metabolic program changes. Inhibition of glycolysis abolished cytotoxic T-lymphocyte (CTL) activity, whereas mitochondrial inhibition had no effect on CTL lytic function. Studies with uniformly labeled 13C-glucose confirmed CTL convert the majority of glucose to lactate. The role of glycolysis in CTL function was assessed using NOD models of Type 1 diabetes (T1D). Treatment of NOD models with a glycolysis inhibitor resulted in reduced and delayed T1D incidence and significantly preserved {beta}-cell mass. We conclude glycolysis and mitochondrial ATP production are essential for efficient T-cell activation, but only glycolysis is essential for CTL lytic function. These data suggest targeting glycolysis in CTLs is a promising pathway to prevent T-cell-mediated autoimmunity.

immunology↗