Preparation Of Fetal CTL Transformed By DC And Its Killing Activity On Tumor Cell Of DU145 And EJ In Vitro

Cytotoxic T lymphocytes(CTL) are the most important effect cell in antitumor immune response in vivo. CTL must be activated through the presentation of appropriate antigen by antigen-present cells(APC). Dendritic cells(DC) are the potentest APC as we known, they can activate not only naive T cells but memory T cell. CTL can be induced by DCs which can provide co-stimulating signal that is indispensable to activation of T cells. Heat shock protein(HSP),called molecular chaprone also, acquired from tumor tissue can bind a varity of antigenic peptides. Vaccination with HSP isolated from tumor cells can elicit tumor- specific immune response. At present there are rather abundant resource of induced fetus in our country. Fetal tissues have not only high ability of proliferation but low immunogenity and graft versus host response(GVHR) is light while transplantation, In our study DC were obtained by culturing plastic adherent mononuclear cells from fetal tissue such as bone marrow, liver and spleen in the presence of certain cytokines. The fetuses we used are from 22 to 32 weeks old. We prepared lysate of tumor cell containing HSP-peptides complex by established method. DC pulsed with the preparation were co-cultured with autologous T cell for three days. Identified by FACS we found the T cell wre transformed into CTL which mainly express CD8+ phenotype. We also compared the killing activity of CTL with lymphokine activated killer(LAK) against tumor cells in vitro and concluded that CTL wre potenter than LAK in specific killing activity. We have successfully obtained DC from fetal tissues and transformed T cell into CTL. Our experiment made foundation for further application of fetal DC and CTL in adoptive immunotherapy of tumors.