Beta-hydroxybutyrate increases ROS formation in human T cells and directs them to memory cell formation in vitro.Figure 3Human peripheral blood mononuclear cells (PBMCs) were cultivated for 48h in RPMI containing 80mg/dl glucose (NC) and supplemented with 10mM beta-hydroxybutyrate (BHB). T cell stimulation was performed through CD3/CD28 Dynabeads at a bead:cell ratio of 1:8. A Quantification of cellular reactive oxygen species (ROS) using CellROX dye, indicated by mean fluorescence intensity (MFI) FITC in human pan/CD4+/CD8+ T cells, n=8/6/6 biological replicates. B Mitochondrial superoxide production quantified through MitoSOX staining, depicted as MFI Phycoerythrin (PE) in human pan/CD4+/CD8+ T cells, n=8/14/14 biological replicates. Data information: Data depicted as box plots with median, twenty-fifth and seventy-fifth percentiles and range. Dots indicating individual values. *p<0.05, **p<0.01, paired t-test/ Wilcoxon matched-pairs signed rank test, as appropriate. Human peripheral blood mononuclear cells (PBMCs) were cultivated for 48h in RPMI containing 80mg/dl glucose (NC) and supplemented with 10mM beta-hydroxybutyrate (BHB). T cell stimulation was performed through CD3/CD28 Dynabeads at a bead:cell ratio of 1:8. C Confocal microscopy images of human CD4+/CD8+ T cells, stained with MitoTracker green, representative of two individual experiments. Human peripheral blood mononuclear cells (PBMCs) were cultivated for 48h in RPMI containing 80mg/dl glucose (NC) and supplemented with 10mM beta-hydroxybutyrate (BHB). T cell stimulation was performed through CD3/CD28 Dynabeads at a bead:cell ratio of 1:8. D Quantification of mitochondrial mass using MitoTracker green, indicated by MFI FITC in human CD4+/CD8+ T cells +/- CD3/CD28 stimulation, n=5/6/6/6 biological replicates. Data information: Data depicted as box plots with median, twenty-fifth and seventy-fifth percentiles and range. Dots indicating individual values. *p<0.05, **p<0.01, paired t-test/ Wilcoxon matched-pairs signed rank test, as appropriate. Human peripheral blood mononuclear cells (PBMCs) were cultivated for 48h in RPMI containing 80mg/dl glucose (NC) and supplemented with 10mM beta-hydroxybutyrate (BHB). T cell stimulation was performed through CD3/CD28 Dynabeads at a bead:cell ratio of 1:8. E Western Blot of mitochondrial oxidative phosphorylation proteins in pan/CD4+/CD8+ T cells as indicated, representative of at least three individual experiments. Human peripheral blood mononuclear cells (PBMCs) were cultivated for 48h in RPMI containing 80mg/dl glucose (NC) and supplemented with 10mM beta-hydroxybutyrate (BHB). T cell stimulation was performed through CD3/CD28 Dynabeads at a bead:cell ratio of 1:8. F Quantification of cellular glutathione content using ThioTracker, indicated by MFI FITC in human CD4+/CD8+ T cells, n=5/6 biological replicates. Data information: Data depicted as box plots with median, twenty-fifth and seventy-fifth percentiles and range. Dots indicating individual values. *p<0.05, **p<0.01, paired t-test/ Wilcoxon matched-pairs signed rank test, as appropriate. Human peripheral blood mononuclear cells (PBMCs) were cultivated for 48h in RPMI containing 80mg/dl glucose (NC) and supplemented with 10mM beta-hydroxybutyrate (BHB). T cell stimulation was performed through CD3/CD28 Dynabeads at a bead:cell ratio of 1:8. For JC1 analysis, magnetic CD4+/CD8+ T cell separation was performed prior to staining. G Evaluation of mitochondrial membrane potential of human pan/CD4+/CD8+ T cells using quantification of JC1 fluorescence (MFI PE/ FITC), FCCP served as the negative control, n=8/7/7/7(FCCP) biological replicates. Data information: Data depicted as box plots with median, twenty-fifth and seventy-fifth percentiles and range. Dots indicating individual values. *p<0.05, **p<0.01, paired t-test/ Wilcoxon matched-pairs signed rank test, as appropriate. Human peripheral blood mononuclear cells (PBMCs) were cultivated for 48h in RPMI containing 80mg/dl glucose (NC) and supplemented with 10mM beta-hydroxybutyrate (BHB). T cell stimulation was performed through CD3/CD28 Dynabeads at a bead:cell ratio of 1:8. H IL15 mRNA expression in stimulated pan T cells, n=6 biological replicates. Data information: Data depicted as box plots with median, twenty-fifth and seventy-fifth percentiles and range. Dots indicating individual values. *p<0.05, **p<0.01, paired t-test/ Wilcoxon matched-pairs signed rank test, as appropriate. Human peripheral blood mononuclear cells (PBMCs) were cultivated for 48h in RPMI containing 80mg/dl glucose (NC) and supplemented with 10mM beta-hydroxybutyrate (BHB). T cell stimulation was performed through CD3/CD28 Dynabeads at a bead:cell ratio of 1:8. I T memory cell differentiation protocol: Following initial incubation and stimulation, CD4+/CD8+ T cells were isolated via magnetic cell separation and cultivated with 50 U/ml IL2 and 25 ng/ml IL15 for an additional 72 hours. Human peripheral blood mononuclear cells (PBMCs) were cultivated for 48h in RPMI containing 80mg/dl glucose (NC) and supplemented with 10mM beta-hydroxybutyrate (BHB). T cell stimulation was performed through CD3/CD28 Dynabeads at a bead:cell ratio of 1:8. J IL15 and IL7R mRNA expression in CD4+/CD8+ T cells after memory T cell differentiation, n=7/6 biological replicates. Data information: Data depicted as box plots with median, twenty-fifth and seventy-fifth percentiles and range. Dots indicating individual values. *p<0.05, **p<0.01, paired t-test/ Wilcoxon matched-pairs signed rank test, as appropriate. Human peripheral blood mononuclear cells (PBMCs) were cultivated for 48h in RPMI containing 80mg/dl glucose (NC) and supplemented with 10mM beta-hydroxybutyrate (BHB). T cell stimulation was performed through CD3/CD28 Dynabeads at a bead:cell ratio of 1:8. Flow cytometry analyses were performed using the indicated dyes and antibodies identifying T cells and CD4+/CD8+ T cell subsets. K Flow cytometric quantification of memory T cells: CD4+/CD8+ T cells were stained for CCR7 (PE+/-) and subsequently defined memory phenotype for CD45RO+ (Pacific Blue+) and CD45RA- (PerCP-) staining. Histogram plots depicting the exemplary change of CD45RO and CD45RA distribution for CD8+ T cells following memory cell differentiation (left side; NC=black, BHB=red). Fractions of CCR7+CD45RA-CD45RO+ central memory (CM) and CCR7-CD45RA-CD45RO+ effector memory (EM) CD4+/8+ T cells (right side), n=12/11/8/7 biological replicates. Data information: Data depicted as box plots with median, twenty-fifth and seventy-fifth percentiles and range. Dots indicating individual values. *p<0.05, **p<0.01, paired t-test/ Wilcoxon matched-pairs signed rank test, as appropriate.