The HK-C60 diet enhances differentiated macrophage activity, leading to CD4+ T cell
activation in an antigen-dependent manner.
A) Experimental design for the HK-C60 diet and immune activation assays. The mice
were first fed the control diet for 1 week (habituation) and then received the
HK-C60 or control diet for the next 2 weeks. TPMs were prepared from the mice in
each group and used for each assay. Cytokine production was analyzed in primary
macrophages of the spleen, liver, and colon. B–D) Cytokine production in
macrophages. TPMs (1.0×106/mL) were treated with LPS (100 ng/mL) or the
vehicle control (PBS) at 37°C for 24 hr, and then the concentrations of IL-6 (B),
TNF-α (C), and IL-12/IL-23p40 (C) in the cultured medium were measured by ELISA.
E–G) Surface marker expression in macrophages. TPMs (1.0×106/mL) were
treated with LPS (100 ng/mL) or the vehicle control (PBS) at 37°C for 6 hr, and then
the expression levels of CD80 (E), CD86 (F), and I-A/I-E (G) were analyzed by flow
cytometry. H–J) Cytokine production in primary macrophages. The splenocytes, liver
mononuclear cells, and colon LP cells were isolated from each mouse and treated with
LPS (100 ng/mL) or the vehicle control (PBS) at 37°C for 6 hr in the presence of
GolgiStopTM. The TNF-α production in macrophages was analyzed by flow
cytometry. K, L) Antigen presentation assay for CD4+ T cells. TPMs (1.0×107/mL) were co-cultured with splenic CD4+ T cells (2.0×106/mL, isolated from OT-II mice) in the presence of OVA323-339 peptide
(100 ng/mL) at 37°C for 24 hr. K) Representative image of IFN-γ+CD4+ T cells in flow
cytometry analysis. L) Percentage of IFN-γ+CD4+ T cells calculated in the flow
cytometry analysis. In the flow cytometry analysis, CD80, CD86, and I-A/I-E
expression (E–G) and TNF-α production (H–J) were detected in the CD11b+F4/80+gate,
and IFN-γ production (K, L) was detected in the CD3+CD4+gate. The cumulative data
are shown as the mean ± SEM of six samples in two independent experiments.
*p<0.05 and **p<0.01 were regarded as indicating significance, respectively.
ns, not significant.