In vitro INDUCTION OF ANTI-TUMOR RESPONSIVENESS BY DENDRITIC CELLS PULSED WITH TUMOR EXTRACTS / 解剖学报

Objective The present study was designed to investigate whether pulsing DCs with tumor-derived extracts is an ef- fective way to induce CTL. and antitumor immunity, Methods DCs were propagated from bone marrow (BM)of C57BL/6J(H-2Kb. I- Ab)mice in vitro with GM-CSF + IL-4tumor associated antigen (TAA) extracted from actively growing Hepa 1-6 cells was used to activate DCs. The phenotypes of DCs were detected by FACS, the cytotoxicity of CTL was as- sayed by 3H-TdR labbel assay. Result and Conclusion The TAA extract pulsed DCs exhibited much more and longer cell processes and increased expression of MHC- Ⅰ, MHC-Ⅱ, CD80 (B7-1 ) 、 CD86 (B7-2 ). This experiment has shown that DCs pulsed with TAA extracts of C57B/6J cells could stimulate effectively the responsiveness of syngenic splenic T cells to induce specific CTL against C57BL/6J cells.

In vitro induction of p210~(Bcr-Abl) protein-specific cytotoxic T cell responses using 562 cell total RNA transfected human dendritic cells / 中国输血杂志

Objective To investigate whether human monocyte-derived dendritic cells (DCs) can express p210 Bcr-Abl protein and induce antigen-specific CTL responses in vitro after transfection with total RNA of K562 cells (K562-RNA).Methods Immature DCs were derived from human peripheral blood monocytes after 5 day incubation in the presence of GM-CSF and IL-4. The cells were then transfected with K562-RNA using electroporation or DOTAP lipofection. To verify the successful transfection of DCs with K562-RNA, Bcr-Abl fusion gene expression was determined by RT-PCR and Western blot. The immune phenotypes of the DCs were analyzed by flow cytometry. CTL cytotoxicity was assayed by propidium iodide (PI) stain and flow cytometry. The amount of DCs, CD1a expression and purity of DCs were measured by FACS.Results Bcr-Abl fusion gene appeared in the DCs after transfection with K562 cell total RNA. But 24 hours later, the Bcr-Abl mRNA from the K562-RNA transfected DCs disappeared, while the cells were expressing p210 Bcr-Abl protein. The transfected DCs could significantly promote T lymphocytes to kill the target K562 cells. We found that PBMC can be induced to DC in culture medium containing human plasma, suggesting a potential for clinical application.Conclusion Human dendritic cells transfected by K562 total RNA can induce effective p210 Bcr-Abl protein-specific immune responses, which might broaden the spectrum of possible DC-based clinical applications.

Anti-tumor responsiveness by dendritic cells transfected with tumor total RNA / 中国免疫学杂志

Objective:The present study was designed to investigate whether transfecting DC with tumor derived total RNA is an effective way to induce CTL and antitumor immunity.Methods:DC were propagated from bone marrow(BM) of C57BL/6J(H 2k b?I A b)mice in vitro with GM CSF+IL 4.Tumor derived total RNA extracted from actively growing Hepa 1 6 cells was used to transfected DC.The phenotypes of DC were detected by FACS,the cytotoxicity of CTL was assayed by MTT method.Results:The tumor derived total RNA transfected DC exhibited much more and longer plasm membrane processes and increased expression of MHC Ⅰ?MHC Ⅱ?CD80(B7 1)?CD86(B7 2).Conclusion:This experiment has shown that DC transfected with tumor derived total RNA of C57BL/6J cells could stimulate effectively the responsiveness of syngenic splenic T cells to induce specific CTL against C57BL/6J cells.