The Study Of The Cellular Immune Therapy Of Her-2Pulsed DCIKs Against Intractable Breast Cancer Cells

Objective:1. to establish CIK-DC co-culture system with Her2-pulsed antigen peptide of DC, induce Her2-specific CTL and provide a technical data for the development of breast tumor vaccine using Her2.2. To study the killer activity of DCIKs-P、DCIKs、epirubicin and herceptin against different breast cancer cells lines.3. To study the killer effect of DCIKs-P on Her-2positive BC cells and Her-2negative BC cells.4. To research the possible mechanism of the DCIKs-P’s killing specificity.Methods:1. CIK and DC were first induced and isolated from human peripheral blood; CIK and DC pulsed with antigen Her2were then co-cultured to prepare CIK-DC co-culture system (DCIK-P).2. By RT-PCR and Western-Blot, the isoforms of DCIKs and BC cells were identified.3.the antigen-specicfic cytotoxicity of DCIK-P against different BC cell lines(SK-BR-3、MCF-7、MDA-MB-231)was compared with the killing activity of DCIKs、epirubicin and herceptin,analysed by cell viability and cytotoxicity assay.4. Using RNAi interfere technology down-regulating the expression of Her-2in SK-BR-3and transfection technology up-regulating the expression of Her-2in MCF-7, reevaluate DCIK-P’s killing activity against these two BC cells lines.Results:1. CIK and DC were first induced and isolated from human peripheral blood; CIK and DC pulsed with antigen Her2were then co-cultured to prepare CIK-DC co-culture system (DCIK-P). The FCM suggested that the isoforms of the MDA-MB-231, SK-BR-3and MCF-7were HLA-A2+Her2+, HLA-A2-Her2+and HLA-A2+Her2-.2. The killer activity of DCIK-Ps、DCIKs、epirubicin and herceptin Cell viability and cytotoxicity assay showed that compared with DCIKs、 epirubicin and herceptin, the killer activity of DCIK-P cells was greatly enhanced against breast tumor cell strains with high expressing level of Her2, whereas no increased killer activity of DCIK-P cells was found against those strains with low Her2expressing level or without the expression of Her2.3. Research of the mechanism of DCIK-Ps’antigen-specicfic cytotoxicity The down-regulating of Her-2expressing level in SK-BR-3and the up-regulating of Her-2expressing level in MCF-7shows a statistical significance in DCIK-Ps’killing activity against these two cell lines, indicating the mechanism of DCIK-Ps’ antigen-specicfic cytotoxicity may be related to Her-2peptide expressing level.Conclusions:1. The killing-activity of Her-2pulsed DCIKs was signicantly increased.2. The killing activity of DCIK-P cells against different BC cell lines is related to their different expressing level of Her-2peptide.3. The expressing level of Her-2peptide in BC cells may be the adjustment point of DCIK-Ps’antigen-specicfic cytotoxicity.