Cytokine-induced Killer Cells Co-cultured With Dendritic Cells Loaded With Protein Lysate Produced By Radiofrequency Ablation Can Induced Specific Antitumor Response

Objective To investigate antitumor activity of dendritic cells (DCs) loading withtumor lysate in situ antigen produced by radiofrequency ablation (RFA) of tumor combinedwith cytokine-induced killer (CIK) cells.Methods Original bone marrow cells of BALB/c mice were induced with GM-CSF,interluki-4(IL-4) and TNF-α. A murine colon carcinoma (C26) model was inoculatedsubcutaneously in male mice. After mice were treated with RFA, supernatant of in situtumor destruction lysis were colleted. DCs were loaded with the antigen to generateAg-DCs. Lymphocytes isolated from spleen of BALB/c mouse were induced withγ-interferon(IFN-γ), CD3McAb,CD28,interluki-2(IL-2)and interluki-1(IL-1),andco-cultured with Ag-DCs to generate Ag-DC-CIK cells. The morphology andimmunophenotype of these cells were determined by microscopy and flow cytometry,respectively. The cytotoxic activity of Ag-DC-CIK cells was determind by CCK-8assay.In subsequent experiments, mice were randomized into Ag-DC-CIK, DC-CIK, CIK, PBScontrol groups and monitored for tumor growth and survival time. Using ANOVA analysisof variance comparing three groups implanted tumor volume trends, Log-rank test tocompare three groups of mice survival time.Results The surface of Ag-DC expressed CD80,CD86,MHC-II,CD11c, respectively,86.3%,29.4%,75.4%,82.5%; untreated DCs expressed costimulatory molecules CD80, CD86,MHC-II,CD11c respectively,68.6%,15.1%,64.5%,66.7%. The main effector cellsof CIK cells were CD3+NK1.1+cells.The percentage of CD3+NK1.1+cells was1.45%onthe first day of the culture,while when they had been cultured for7days, the percentageCD3+NK1.1+was significantly increased to36.9%. The cytotoxicity of Ag-DC-CIK cellstoward C26cells was much more efficient than DC-CIK,CIK cells. Rechallenged mice inAg-DC-CIK group demonstrated significant tumor inhibition and prevention comparedwith DC-CIK group,CIK group,PBS control group.Conclusions The DC loading with tumor in situ lysate antigen produced byradiofrequency ablation combined with CIK cells might be a novel strategy for cancertreatment.