Related Experiment Videos
Perforin-dependent NK cell cytotoxicity is sufficient for anti-metastatic effect of IL-12
T Kodama1, K Takeda, O Shimozato
1Department of Immunology, Juntendo University School of Medicine, Tokyo, Japan.
Abstract:
IL-12 exerts a potent anti-tumor effect, which is possibly mediated by multiple mechanisms including activation of NK and NKT cells, induction of cytotoxic T lymphocytes, and inhibition of angiogenesis. In the present study, we characterized the cytotoxic effector cells and mechanisms responsible for the anti-metastatic effect of IL-12. Administration of IL-12 had a comparable inhibitory effect on experimental lung metastasis of B16 melanoma cells in wild-type C57BL/6 mice and RAG-2-/- mice that lack T and NKT cells, which was abolished by depletion of NK cells. Cytotoxic activity of liver and splenic mononuclear cells against B16 was induced by IL-12 administration in RAG-2-/- mice at a level comparable to that in wild-type mice, which was also abolished by depletion of NK cells. Moreover, the anti-metastatic effect of IL-12 was abrogated by perforin deficiency, but not by Fas ligand deficiency, in association with a lack of IL-12-induced cytotoxic activity of liver and splenic mononuclear cells against B16. These results suggest that perforin-dependent cytotoxicity of IL-12-activated NK cells is sufficient for the anti-metastatic effect of IL-12.
Insights
Interleukin-12 (IL-12) demonstrates significant anti-metastatic properties by activating natural killer (NK) cells. This perforin-dependent NK cell cytotoxicity is crucial for IL-12
Area of Science:
- Immunology
- Cancer Biology
- Cellular Mechanisms
Background:
- Interleukin-12 (IL-12) is known for its potent anti-tumor effects.
- Potential mechanisms include NK and NKT cell activation, CTL induction, and anti-angiogenesis.
- The specific effector cells and mechanisms underlying IL-12's anti-metastatic activity require further elucidation.
Purpose of the Study:
- To characterize the cytotoxic effector cells responsible for the anti-metastatic effect of IL-12.
- To elucidate the mechanisms mediating IL-12's inhibition of experimental lung metastasis.
Main Methods:
- Utilized wild-type C57BL/6 mice and RAG-2-/- mice (lacking T and NKT cells).
- Administered IL-12 and assessed its effect on B16 melanoma lung metastasis.
- Depleted NK cells and analyzed perforin and Fas ligand deficiency.
- Measured cytotoxic activity of liver and splenic mononuclear cells against B16 melanoma cells.
Main Results:
- IL-12 inhibited experimental lung metastasis in both wild-type and RAG-2-/- mice.
- The anti-metastatic effect of IL-12 was abolished by NK cell depletion.
- IL-12 administration induced comparable cytotoxic activity in RAG-2-/- and wild-type mice, dependent on NK cells.
- Perforin deficiency abrogated the anti-metastatic effect and IL-12-induced cytotoxicity, while Fas ligand deficiency did not.
Conclusions:
- Perforin-dependent cytotoxicity mediated by IL-12-activated NK cells is sufficient for IL-12's anti-metastatic effect.
- NK cells are the primary cytotoxic effector cells mediating IL-12's anti-metastatic action.
- The mechanism involves perforin-mediated killing, independent of T and NKT cells.