Characterizing Human Peripheral Blood Lymphocyte Phenotypes and Their Correlations with Body Composition in Normal-Weight, Overweight, and Obese Healthy Young Adults

In conclusion, the baseline immunological profile of PB is influenced by excessive adipose tissue in healthy young adults.

The following BCIs were measured: waist circumference, hip circumference, height, waist-to-hip ratio, waist-to-height ratio, total body fat mass, visceral fat level, weight, and BMI. White blood cell count (WBC), Ly absolute count, serum TNF-α, and IFN-γ were quantified. Ly subpopulations were analyzed as follows: total TLy (TTLy-CD45+CD3+), early activated TLy (EATLy-CD45+3+69+), total NKLy (TNKLy-CD45+CD3-CD56+CD16+), NKdim (low expression of CD56+), NKbright (high expression of CD56+), BLy (CD45+CD3-CD19+), T helper Ly (ThLy-CD45+CD3+CD4+), and T cytotoxic Ly (TcLy-CD45+CD3+CD8+).

Higher BMI has significantly higher WBC and BLy (p < 0.0001; p = 0.0085). EATLy significantly decreased from NW to OB (3.10-NW, 1.10-OW, 0.85-OB, p < 0.0001). Only EATLy exhibited significant negative correlations with all the BCIs. A significantly higher TNF-α was observed in the OW and OB groups compared to the NW group. IFN-γ increased linearly but nonsignificantly with BMI. TTLy showed a nonsignificant positive correlation with both IFN-γ and TNF-α, while EATLy showed a negative correlation, significant only for IFN-γ. NKLy subpopulations exhibited a consistent negative correlation with TNF-α, significant only for NKdim (p = 0.0423), and a nonsignificant consistent positive correlation with IFN-γ. A nonsignificant negative correlation between age and both TNKLy (r = -0.0927) and NKdim (r = -0.0893) cells was found, while a positive correlation was found with NKbright (r = 0.0583). Conclusions: In