小兒科Lo, C.-H.C.-H.LoLee, S.-C.S.-C.LeeWu, P.-Y.P.-Y.WuPan, W.-Y.W.-Y.PanSu, J.J.SuCheng, C.-W.C.-W.ChengRoffler, S. R.S. R.RofflerChiang, B.-L.B.-L.ChiangLee, C.-N.C.-N.LeeWu, C.-W.C.-W.WuTao, M.-H.M.-H.Tao2008-12-292018-07-112008-12-292018-07-112003http://ntur.lib.ntu.edu.tw//handle/246246/94855The structure and T cell stimulatory effects of the recently discovered cytokine IL-23 are similar to, but distinct from , those of IL-12. Although the antitumor activities of IL-12 are well characterized, the effect of IL-23 on tumor growth is not known. In this study, murine CT26 colon adenocarcinoma and B16F1 melanoma cells were engineered using retroviral vectors to release single-chain IL-23 (scIL -23) to evaluate its antitumor activity. In BALB/c mice, scIL-23-transduced CT26 cells grew progressively until day 26 to an average size of 521 +/- 333 mm(3), then the tumors started to regress in most animals, resulting in a final 70% rate of complete tumor rejection. scIL-23 transduction also significantly suppressed lung metastases of CT26 and B16F1 tumor cells. In addition, mice that rejected scIL-23- transduced tumors developed a memory response against subsequent wild-type tumor challenge. Compared with scIL-12- expressing CT26 cells, scIL-23-transduced tumors lacked the early response , but achieved comparable antitumor and antimetastatic activity. These results demonstrated that IL- 23, like IL-12, provided effective protection against malignant diseases, but it probably acted by different antitumor mechanisms. As a first step in identifying these antitumor mechanisms, tumor challenge studies were performed in immunocompromised hosts and in animals selectively depleted of various lymphocyte populations. The results showed that CD8(+) T cells, but not CD4(+) T cells or NK cells, were crucial for the antitumor activity of IL-23.en-USIFN-GAMMA PRODUCTIONTUMOR-REGRESSIONIMMUNE-RESPONSECOLON- TUMORT-CELLSINTERLEUKIN-12journal article