Effects Of CTLs Mediated By Dendritic Cells Which Derived From Leukemia Cells To Kill And Wound Tumors

Master Degree Candidate: Yu Zhiyong Supervisor:Chen Hu, ProfessorPurpose: Immunotherapy is a new method to cure tumors after other methods, such as operation, irradiation, chemotherapy and biotheraphy, it' s technology is more and more maturer, and the treatment is more securer. But it' s difficult to improve the treatment efficiency to reduce relapse rates and to avoid all kinds of complications which are the most important study components in tumor immunotherapies. Dendritic cell(DC) is the most powerful antigen presenting cell (APC) by now which can activate T cell (especially naive T cell),Th cell , NK cell, and promote B cell' s proliferation and maturity. It can not only activate immunity of autobody to attack tumor cells, but also do help for allogenic bodies. Immunotherapies with DCs to cure tumors are used in clinical fields now, and we do know that they are safe and useful. How to improve specificity of DC is now a new question. Dendritic cells derived from Leukemia cells have the specific antigens. It' s a good way to use them to mediate CTL to kill and wound tumors, and is a new method of anti-leukemia immunotherapy.Method: DCs were cultured from myelogenous leukemia cells(include CML, AML-M3 and AML-M4 ), observed under optic microscope, scanning electron microscope and transmiting electron microscope and were detected on their characteristic phenotypes with chromatosomes to definite where they are from. The efficiency of differentiation was detected and the growth curvewas also drawn. Characters of DCs after cryopreservation were studied too. At5last, DCs were incubated with leukemia cells and CTLs, added in LDH substrate fluid , and assaied optical densities in 570nm.Results:All the DCs cultured from CML cells shown characteristic screenages of DC no mater under optic microscope, scanning electron microscope and transmiting electron microscope , and their phenotypes were characteristic, they all had PH1 chromatosomes . DCs cultured from AML-M3 andAML-M4 cells shown characteristic stigmatas too. Characters of DCs after cryopreservation don' t change. Killing and wounding tests shown that DCs can improve the effects of CTLs to attack tumors, and the effects will be improved with more DCs existed. These phenomena were verified by statistic analysis.Conclusion:1. DCs can be cultured with cytokines from Leukemia cells.2. These DCs reserved the specific tumor antigens.3. Characters of DCs after cryopreservation don' t change.4. Dendritic cells derived from Leukemia cells have the specific antigens, they can improve the effects of CTLs to attack tumors, and the stimulations have positive correlation with DCs' quantity.