| First Author | Takahashi M | Year | 1996 |
| Journal | J Immunol | Volume | 156 |
| Issue | 7 | Pages | 2436-42 |
| PubMed ID | 8786302 | Mgi Jnum | J:31935 |
| Mgi Id | MGI:79439 | Doi | 10.4049/jimmunol.156.7.2436 |
| Citation | Takahashi M, et al. (1996) LPS induces NK1.1+ alpha beta T cells with potent cytotoxicity in the liver of mice via production of IL-12 from Kupffer cells. J Immunol 156(7):2436-42 |
| abstractText | We recently reported that systemic administration of IL-12 into mice activates NK1.1+ alpha beta T cells with intermediate TCR (NK1+TCRint) and induces strong MHC-unrestricted cytotoxicity in C57BL/6 mice. In the present report, we examined the effect of LPS on Kupffer cells and NK1+TCRint, cells in C57BL/6 mice. Administration of LPS, as well as synthetic lipid A analogue (ONO-4007), but not detoxified LPS, induces the increase of NK1 expression of NK1+TCRint cells (NKlhighTCRint) and the acquisition of strong MHC-unrestricted cytotoxicity of these cells against NK-sensitive and NK-resistant targets as does IL-12 administration. LPS as well as ONO-4007 induced IL-12 mRNA in hepatic mononuclear cells, mainly in plastic-adherent Kupffer cells. LPS-induced cytotoxicity of hepatic mononuclear cells was greatly reduced by in vivo injections of anti-IL-12 Ab, to a lesser extent by anti-IFN-gamma Ab, but not by anti-IL-1 nor anti-TNF-alpha Ab. Pretreatment of mice with LPS induced inhibition of hepatic metastases of i.v. injected EL4 cells in C57BL/6 euthymic and athymic mice and this antimetastasis was inhibited by injection of anti-IL-12 Ab. This antimetastatic effect of LPS in the liver was also observed in different strains of mice and tumors, In contrast to IL-12, however, LPS was not so effective when administered after tumor inoculation. These results revealed that LPS (lipid A) stimulates NK1+TCRint cells through IL-12 production from Kupffer cells and suggest that bacterial components, probably including those from intestine, are activators of Kupffer cells and NK1+TCRint, cells in the liver. It is also suggested that the host condition as well as LPS-induced cytokines other than IL-12 may affect antitumor effect induced by LPS in the liver. |
