The Persistent Secretion of TNF-? by60Co Irradiated TNF Gene Modified Human Hepatoma Cell / 中国肿瘤生物治疗杂志

ABSTRACT

?-tumor necrosis factor can enhance tumor cells autolysis and the expression of HLA antigenes. So we infected Human Hepatoma Cell Line (HHCL)with recombinant retroviral vector containing an insert of human tumor necrosis factor-? cDNA. The transduced tumor cells were isolated by G418 selection. After being irradiated by different doses of 60Co, their expression of TNF in 24 hours were tested. Observations of the relationship between the doses of irradiation and the expression levels of TNF were done. We also preserved the irradiated HHCL-TNF cells into liquid nitrogen, after recovering, tested their expressions of TNF again. This paper shows that (l)following irradiation by 60Co, the production of ?-TNF persisted for about four weeks, and there is no difference among the different irradiated doses(40G~100G); (2)After being irradiated and kept into liquid nitrogen, the recovering HHCL-TNF cells constitutively secrete ?-TNF for about three weeks.These findings provide a logical basis for designing protocols for active immunotherapy in humans.