Dendritic Cells Derived From Lymphoma Cells Transduced By Recombinant Adenovirus Encoding Human P53 Elicit Potent Anti-tumour Immunse Response

Objective Dendritic cells(DCs)are the most potent professional antigen presenting cells(APCs)for naive T cells and play an important role in cancer immunology in vivo. They can provoke specific immune response to specifically kill the cancer cells but not to do harmful effects on normal ones.Lymphoma-DCs(L-DCs)from patients themselves with lymphoma antigens have no restriction of MHC and can promote specific cancer immunology,so they will probably play an important role in cancer treatment.But L-DCs are relatively less immature than normal CD83~+ DCs derived from CD14~+ or CD34~+ precursor cell.Because DCs function depends on their maturation,it is necessary in theory and practice to how to get the mature DCs with normal function.Recombinant adenovirs encoding human p53(rAd-p53)is known to be a differentiating agent in the treatment of solid tumor(ST).The treatment of ST by rAd-p53 is so successful that it becomes possible of cured-ST,but most of the Lymphoma patients died of minimal residual disease(MRD) or recidivism in the end.If DCs from Lymphoma cells by rAd-p53 are mature,they will probably become tumor vaccine used in Lymphoma treatment.Therefore,we will probably solve the problems of MRD and recidivism of Lymphoma in the future.In this study,we investigated whether rAd-p53 can differentiate the diffuse large B cell lymphoma(DLBCL) cells to DCs and whether these differentiated cells can activate T cells,which provides the theoretical foundation for using of rAd-p53-DC vaccine in practice.Methods Lymph node mononuclear cells and peripheral blood mononuclear cells derived from the same patient before the initial treatment,who was diagnosed DLBCL with specific pathologic diagnosis were cultured to DCs in complete medium.Some DCs were treated by rAd-p53.Some DCs were treated by adenovirus.The others were treated by nothing.We put them into three groups:Experiment groupA(L-rAd-p53-DC group), Experiment groupB(P-rAd-p53-DC group);Control group A(L- rAd-DC group),Control group B(P- rAd-DC group);Blank groupA(L-N-DC group),Blank groupB(P-N-DC group).Experiment group and blank group were respectively added rAd-p53 and adenovirus.All groups were added by TNF-a and CD40mAb on the 8 th day.After 48 hours, the cell phenotypes of DCs were analyzed by flow cytometry,at the same time,the secretion of IL-12 were analyzed by ELISA.Cell_s morphous was observed every day. Finally T cell proliferative activity(MLR)and the antitumor effect of rAd-p53-treated DCs (CTL Effect)targeted at DLBCL cells were detected by LDH.At the same time,peripheral blood mononuclear cells derived from the same patient were cultured to the reponsed cells in complete medium.Results Mononuclear cells derived from Lymph node and peripheral blood were cultured to DCs and reponsed cells in complete medium.experiment group and control group and blanh group were successfully cultured into DC-like cells.The cell phenotypes of experiment group and control group cultured in the 10th day were analyzed by flow cytometry,and the results suggested that the surface molecule expressions:CD83,CD80,CD86 and HLA-DR were more significantly high in experiment group than in and control group and blank group,both experiment group and control group(p<0.05),except for CD1a in rAd -DCs(p>0.05).The secretion of IL-12 in supematant was greatly higher in experiment than in control group.We also found that experiment group had a more significant increase in autogene T lymphocyte proliferation and cytotoxic activity against the same kind of DLBL-celIs than in control group and blank group(p<0.05),furthermore, the ability to stimulate T lymphocyte proliferation increased with the rise of the ratio of experiment group and T lymphocyte.However,rAd-p53-DC derived from Lymph node and peripheral blood were differences(p<0.05).Conclusion rAd-p53-DLBCL-cells can be cultured into DCs which are mature enough by rAd-p53 treatment.After the treatment of rAd-p53,the yield of DC increases greatly, and T lymphocyte proliferation(MLR)stimulated by rAd-p53-DCs is enhanced markedly as well as T cytotoxic activity against DLBCL-cells(CTL effect),whereas, recomadenovirus-DCs are able to stimulate allogene T lymphocyte cell proliferation too,but it is low...