Figure 4.

Ginsenoside F1 (G-F1) enhances NK cell-mediated protection against pulmonary metastatic melanoma in vivo. (A,B) C57BL/6 mice (n = 7 per group) received either G-F1 (50 mg/kg; i.p.) or vehicle for 3 consecutive days before an i.v. injection of 5 × 10⁵ B16F10 cells and thrice a week administration thereafter. After 14 day of tumor implantation, mice were euthanized and number of metastatic tumor colonies in the lungs was counted after fixation. Representative lung image (A) and summary graph of statistical bar charts (B) showing pulmonary metastases of B16F10 cells. Values represent means ± s.e.m. (C,D) C57BL/6 mice (n = 4 per group) received either G-F1 (50 mg/kg; i.p.) or vehicle as described above. Thereafter, splenic NK cells were isolated and incubated with YAC-1 target cells in a 1:1 ratio for 4 h. Cytotoxic degranulation was measured by determining surface expression of CD107a on CD3ε-NKp46+ NK cells. Representative flow cytometry profile (C) and summary graph of statistical bar charts (D) showing percentage of CD107a+ NK cells. Values represent means ± s.d. ^*p < 0.05; ^***p < 0.001 by Student's t-test.