Dendritic Cells Derived From Chronic Myelogenous Lekumia Transduced By Recombinant Adenovirus Encoding Human P53 Elicit Potent Anti-lekumia Response

Objective:Dendritic cells(DCs)are the most powerful profession antigen-presenting cells(APCs)in vivo and play a crucial role in the immune responses.DCs have been successfully used in clinical trails to induce tumor-specific immune response.Leukemia-DCs(L-DCs)from patients themselves with leukemia antigens have no restriction of MHC and can promote specific cancer immunology,so they will probably play an important role in cancer treatment.Although the DCs derived from patients with leukemia have the similar morphology and immunophenotype with DCs from normal individuals,the immunological function are weaker.Because DCs' function depends on their maturation,it is necessary in theory and practice to get the mature DCs with normal function.The p53 gene is the most important turnout suppressor gene,Many types of cancer have been found to be associated with mutations of the p53 gene,re-establishing the p53 gene to treating cancer emerged a number of exciting potention in cancer gene therapy.DCs transduced with virus vector encoding tumor-associated antigen were shown to induce specific antitumor immunity in vitro and invivo.Here,we report our findings that DC originated from chronic myelocytic leukemia(CML)patients transduced with wild-type p53 are able to promote maturation and cytokine produce of CML-DCs and elicit potent anti-turnout immune responses specific for the k562 cells,bearing a mutant human p53 gene. Methods:Bone marrow mononuclear cells(BMMNCs)were isolated from CML patients by density gradient centrifugation and were cultured in RPMI-1640 culture medium supplemented with recombinant human(rh)GM-CSF and rhlL-4.Then the immature DCs cultured with rAd-p53+TNF-awere experiment group,the immature DCs cultured with LacZ+TNF-awere control group,the immature DCs cultured with only TNF-awere blank group.All cells were harvested after 72h,then the morphologic features were observed and the phenotypes were analyzed by flow cytometry,IL-12 concentration were detected by ELISA kits,Mixed lymphocyte reaction were analyzed by MTT assay and the antitumor effect(CTL Effect)targeted at K562 cells were detected by LDH release reaction.Results:It was demonstrated that all DCs derived from CML-BMMNCs showed the typical morphology.The immunophenotype expressed on DCs,such as CD80, CD86,CD83,HLA-DR,CDla,were more significantly high in experiment group and in control group then blank group(P<0.05).The secretion of IL-12in supernatant was greatly higher in experiment group than in controy group.Chromosomes of CML-DCs were detected that most of them had the typical cytogenetic abnormality of CML: (9;22)(q34;q11).We also found that experiment group(rAd-p53-CML-DC)had a more significant increase in autogene T lymphocyte proliferation and cytotoxic activity against the K562 cells than in control group and blank group(p<0.05).Conclusion:This study indicates that the CML-DC transduced with wild-type p53 could be able to promote maturation and cytokine production of CML-DCs and elicit potent anti-tumour immune responses specific for the k562 cells,bearing a mutant of p53 gene.This maybe provide a new protocol to achieve anti-tumor immunity by DC-based vaccination.