Induction of monocyte antitumor response by human cancer cells transduced with TNF-GFP fusion gene: possible implications for immunotherapy of cancer.
This study was undertaken to determine how human pancreatic cancer (HPC-4) cells transduced with the TNF-GFP fusion gene (TLG) alter the antitumor response of human monocytes in vitro and whether they could act as an antitumor vaccine. In our model, HPC-4 cells were transduced with retroviral vector harboring TLG gene and designated as HPC-4(TLG). The TLG protein expression was confirmed by Western blot and flow cytometry analysis. Monocytes were co-cultured with transduced and control HPC-4 cells. The secretion of TNF, IL-10 and IL-12 was measured by ELISA. The cytotoxicity of monocytes against HPC-4 cells was determined by MTT test. The results show that the HPC-4(TLG) cells expressed membrane-bound, intracellular and secretory TLG protein. When cultured with HPC-4(TLG) cells, monocytes released a higher amount of TNF, but IL-10 and IL-12 secretion was inhibited. The pre-exposure of monocytes to HPC-4(TLG), but not to HPC-4, cells did not decrease TNF nor increase IL-10 production, thus not leading to monocyte deactivation. Also, the antitumor cytotoxicity of monocytes stimulated with HPC-4(TLG) was not downregulated, which occurred when non-transduced HPC-4 cells were used. In conclusion, compared to parental HPC-4 cells, TLG gene transduced HPC-4 cells induced stronger antitumor response of monocytes in vitro and prevented deactivation of monocytes.
Department of Clinical Immunology, Polish-American Institute of Pediatrics, Jagiellonian University Medical College, Krakow, Poland. miwiecki@cyf-kr.edu.pl
Jerzy
J
Więckiewicz
Bożenna
B
Mytar
Rafał
R
Szatanek
Kazimierz
K
Węglarczyk
Jarosław
J
Baran
D000818:Animals; D016207:Cytokines / Q000276:immunology; D005822:Genetic Vectors; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007167:Immunotherapy / Q000379:methods*; D051379:Mice; D009000:Monocytes / Q000166:cytology / Q000276:immunology*; D010190:Pancreatic Neoplasms / Q000235:genetics / Q000628:therapy*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism*; D012190:Retroviridae / Q000235:genetics / Q000378:metabolism; D014161:Transduction, Genetic; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism*
D016207:Cytokines; D011993:Recombinant Fusion Proteins; D014409:Tumor Necrosis Factor-alpha; D049452:Green Fluorescent Proteins