Effector Memory CD8(+) and CD4(+) T Cell Immunity Associated with Metabolic Syndrome in Obese Children

PURPOSE: We investigated the association of effector memory (EM) CD8(+) T cell and CD4(+) T cell immunity with metabolic syndrome (MS). METHODS: Surface and intracellular staining of peripheral blood mononuclear cells was performed. Anti-interleukin-7 receptor-alpha (IL-7Rα) and CX3CR1 antibodies were used to stain the subsets of EM CD8(+) T cells, while anti-interferon-gamma (IFN-γ), interleukin-17 (IL-17), and forkhead box P3 (FOXP3) antibodies were used for CD4(+) T cell subsets. RESULTS: Of the 47 obese children, 11 were female. Children with MS had significantly higher levels of serum insulin (34.8±13.8 vs. 16.4±6.3 μU/mL, p<0.001) and homeostasis model assessment of insulin resistance (8.9±4.1 vs. 3.9±1.5, p<0.001) than children without MS. Children with MS revealed significantly higher frequencies of IL-7Rα(low) CD8(+) T cells (60.1 ±19.1% vs. 48.4±11.5%, p=0.047) and IL-7Rα(low)CX3CR1(+) CD8(+) T cells (53.8±20.1% vs. 41.5 ±11.9%, p=0.036) than children without MS. As the serum triglyceride levels increased, the frequency of IL-7Rα(low)CX3CR1(+) and IL-7Rα(high)CX3CR1(–) CD8(+) T cells increased and decreased, respectively (r=0.335, p=0.014 and r=−0.350, p=0.010, respectively), in 47 children. However, no CD4(+) T cell subset parameters were significantly different between children with and without MS. CONCLUSION: In obese children with MS, the changes in immunity due to changes in EM CD8(+) T cells might be related to the morbidity of obesity.