Fig. 4.

Altered immune cell profile in blood of mice fed an energy-dense (ED) diet. Peripheral blood leucocyte frequencies were compared in mice fed a standard (SD; n=16) and ED (n=15) diet for 30 weeks. (A) Compared with control mice, the percentage of B cells was significantly increased in blood from ED diet-fed mice and corresponded with trend for decreased percentage of total T cells, though this did not reach statistical significance (P=0.056). (B) The total number of T_helper (T_h, CD4⁺) cells was reduced in peripheral blood from ED diet-fed mice and was reflected by a significantly lower ratio of T_h:T_cytotoxic (T_c) cells when compared with mice fed a SD diet for 30 weeks. (C) The proportion of T_regulatory cells (T_reg, CD4⁺CD25⁺) was significantly lower in blood from mice fed an ED diet for 30 weeks, despite comparable absolute numbers of T_reg cells between dietary groups (P=0.28). (D) Similarly, the percentage of peripheral blood natural killer T (NKT) cells was significantly reduced for ED diet-fed mice with a trend for an overall reduction in the total number of NKT cells (P=0.1). Data are mean±95% c.i. Significant differences were analysed by Student's t-test with Welch's correction and indicated as *P≤0.05, **P≤0.01.