Fig. 1

Associations between ISI_OGTT, immune cell frequencies, and cytokine levels in older participants. a-h Insulin sensitivity index (ISI_OGTT) was correlated with body mass index (BMI), leukocytes, naïve CD4⁺ T cells (T_NAIVE, CD45RA⁺CCCR7⁺CD27⁺CD28⁺), central memory CD4⁺ T cells (T_CM, CD45RA⁻ CD27⁺CD28⁺), naïve CD8⁺ T cells (T_NAIVE, CD45RA⁺CCR7⁺ CD27⁺CD28⁺), central memory CD4⁺ T cells (T_CM, CD45RA⁻CD27⁺CD28⁺), regulatory CD4⁺ T (Treg) cells (FoxP3⁺CD25^high), and IL-6 levels. Spearman correlation analysis was conducted. * p < 0.05. Each dot represents one participant. Male participant (black). Female participant (grey)