| Objective Dendritic cells (DCs) are the most potent professional antigen presenting cells (APCs) in vivo. They not only can provoke specific immune response which can kill the target specifically, but also can promote the non-specific immunocyte cytotoxicity. Cytokine-induced killer cells (CIKs) derived from mononuclear cells existed in peripheral blood, bone marrow or cord blood can be obtained under the presence of IL-2, IL-1, IFN-gamma and monoclonal antibody against CD3 for a period of time. CIKs considered as a kind of immunocyte equipped with cytotoxicity can kill the tumor cells by the mechanism of non-MHC restricted killing. It had been reported that DC can become more mature, secrete more IL-12, after DC cocultured with CIKs. And after they cocultured, CIKs can become more power such as proliferation, the secretion of IFN-gamma and the ability of killing target cells. Interestingly, after DC cocultured with T cells, DC also can secrete more IL-12 and T cells can secrete more IFN-gamma. CD3~+CD56~+cells considered as the main effector cells of CIKs in non-MHC restricted killing constituted a median of 35.5% of the total cell population, CD3~+CD56~- cells constituted a median of 58% of the total, of which the main bulk were demonstrated to be CD8~+ cells .At the beginning of the CIK culture, the phenotype of CD45RA, a kind of marker of naive T cells, was high and it become lower when CIKs become more mature. The above materials suggest there maybe are a certain of T cells among CIKs, could T cells have the specific killing effect to tumor cells expressed tumor special antigens? In order todemonstrate the deduction drew above, the experiment was designed: the first, MCF-7/ADR expressed P-gp antigen, a kind of cell line of mammary cancer, was melted to obtain the antigen lyses including the P-gp antigen, the second, let the antigens impact DCs to get pulsed-DCs, and the third, put the pulsed-DCs and CIKs together to coculture, and the end, the specific antitumor effect, which is coculturing cells killing MCF-7/ADR expressed P-gp, was observed.Methods Bone marrow mononuclear cells (BMMNCs) derived from healthy person were separately cultured to DC and CIK. Some DC impacted with tumor antigen lyses. We put them into three groups: pulsed-DC coculturing with CIKs (pulsed-DC-CIK);DC coculturing with CIKs (DC-CIK);CIK cultured 15d was used as control. Then, the cell phenotypes of DC and CIK were analyzed by flow cytometry, at the same time, the secretion of IL-12 and IFN-gamma were analyzed by ELISA. And the antitumor effect of the three CIK groups targeted at MCF-7/ADR expressed P-gp antigen and MCF-7 were detected by MTT.Results Pulsed-DC-CIK group and DC-CIK group expressed higher mature phenotypes than that of before they cocultured with CIK, which had significant difference (P=0.003, P=0.001). It also had difference on phenotypes of CIK among the three groups mentioned before after coculture (pulsed-DC-CIK vs CIK, P=0.011;pulsed-DC-CIK vs DC-CIK, P=0.003;DC-CIK vs CIK, P=0.039). The phenotypes of CIK also had significant difference between culturing 15d and 7d (P=0.014).Among the three CIK groups, pulsed-DC-CIK group had the highest phenotypes on CD3+CD56+(pulsed-DC-CIK vs DC-CIK, P=0.001;pulsed-DC-CIK vs CIK, P<0.001) and CD3+CD8+ (P=0.002, P=0.002). On CD45RA phenotype, pulsed-DC-CIK had the lowest one among the three group (pulsed-DC-CIK vs DC-CIK, P<0.001;pulsed-DC-CIK vs CIK, P=0.004). The secretion of IL-12 and IFN-gamma had the highest level on pulsed-DC-CIK group among the three, and the results were 254±14.5pg/ml and 3100±286pg/ml. The antitumor effect of killing MCF-7/ADR had significant difference between any two groups (pulsed-DC-CIK vs DC-CIK, P=0.039;pulsed-DC-CIK vs CIK, P=0.002;DC-CIK vs CIK, P=0.049), the highest is pulsed-DC-CIK group, the lowest is CIK group. As far as MCF^7 was concerned, theCIK group had the lower antitumor effect than the other two groups (pulsed-DC-CIK vs CIK, P=0.007;DC-CIK vs CIK, P=0.048), and the killing effect between the other two groups had no difference .Conclusion We could successfully obtain DC and CIK from bone marrow mononuclear cells after culturing. After they cocultured , both of them not only can increase their own specific phenotypes but also can secrete their associated cytokines. We observed the improved killing effect and some possible specific immunocyte cytotoxicity, but the exact mechanism needs further research. |
PDF Full Text Request