Figure 1.

Aging-related phenotype, cell expansion, and cell cycle analysis of NK cells. (a-e) The human NK cells treated with calcitriol or rapamycin for 72 h showed the following cell biomarkers: natural killer group 2 member A (NKG2A), cluster of differentiation 16 (CD16), T cell immunoglobulin and mucin domain-containing protein 3 (TIM3) programmed cell death-1 (PD-1), and killer immunoglobulin-like receptor (KIR), which were related to aging. 50 nM rapamycin (RAPA) was used as the positive control. n = 3 for each group. *P < 0.05 and **P < 0.01 were compared with the negative control (NC) group. (f) NK cells (right) isolated from human peripheral blood mononuclear cells (PBMCs, left) by Magnetic bead sorting. (g) Cell proliferation analysis measured by cell counting kit 8 (CCK8). (h) Effect of calcitriol or rapamycin on the cell cycle in sorted NK cells after treatment for 72 h. *P < 0.05, ●P < 0.05, and #P < 0.05 indicated the significant differences in the G1, S, and G2 phases, respectively. All the groups were compared with NC, respectively. n = 3. (i) The percentage of T cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif (ITIM) domain (TIGIT)-positive NK cells after treatment with calcitriol or rapamycin for 72 h. *P < 0.05 and **P < 0.01 were compared with NC. n = 3