ABSTRACT
In order to study the enhancement of immune functions and autologous tumor-killing (ATX) activity by kappa-selenocarrageenan (KSC) in mice bearing sarcoma 180, the effects of KSC and/or Cyclophosphamide (Cy) on natural killer(NK) activity, lymphokine activated killer(LAK) activity, the production of interleukin-2 (IL-2), ATK activity and the growth of sarcoma 180 (S180) were observed. The results showed that KSC promoted NK activity, LAK activity and ATK activity in vivo, increased IL-2 production at 40mg/kg ?d x 9d. It also enhanced the antitumor action of Cy (20mg/kg?d x 9d) and offsetted the inhibition of Cy on immunocompetent cells. The ATK activity in splenocytes of SI80-bearing mice could be induced and augmented by recombinant interleukin-2 (rIL-2) in vitro. In conclution, KSC had a up-regulating effect on immune functions and ATK activity in tumor-bearing mice, therefore, can be used as a biological response modifier (BRM) in cancer biotherapy.
ABSTRACT
Using ovarian cancer cell lines, we studied relationship between C-erbB2 expression and lysis activity of lymphokine-activated killer cells (LAK) and in vitro regulation by ?-interferon (IFN-?). The results showed that C-erbB2 overexpression was associated with resistance to lysis activity of LAK in ovarian cancer; IFN-? could reduce the overexpression of C-erbB2 and increase lysis activity of LAK on ovarian cancer cells in which C-erbB2 were overexpressed.
ABSTRACT
TIL were isolated from the resected tumor mass,and lymphocytes were separated from pe-ripheral blood of 12 patients with osteosarcoma.In vitro antitumor activity and spesificity of rIL—2 activated TIL and LAK cells were determined by 4 hour ~(51)Cr releasing assay.Phenotypeanalysis of TIL were carried out in different intervals of incubation.The results revealed thatduring the incubation period from Day 15—Day 20,the difference between average cytolytic ac-tivities of TIL and LAK ceils with K562 and LiBr cells as target cells(E:T ratio 25:1)were in-significant,while that from 7 of those patients with autotumor cells as target cells were signifi-cant.The phenotype analysis showed that the percentage of CD3~+ cells remained constant,whilethat of CD4~+ cells tends to increase,and that of CD8~+cells tends to decrease during the whole in-cubation period.
ABSTRACT
We previously demonstrated the cytotoxicity of human LAK cells to solid tumors in vitro. The work we reported here investigated the mechanisms involved in killing of solid tumor cells by LAK cells. It was shown that the cytotoxicity of LAK cells was mediated by some factors secreted by LAK cells and effects of direct contact with targets. Following lysis, the nucli of targets were destroyed and fragments of DNA were released into the medium. The cytotoxicity of LAK cells, under some circumtances, was of a positive correlation to the proliferation of themselves.
ABSTRACT
It was demonstrated that TILs exhibited higher cytotoxicity to autologous tumor cells than that of LAK cells grown under identical conditions, and TILs had target cell specificity.The cytotoxicity of TILs to other tumor cells was lower than that of LAK cells, and TILs had no cytotoxicity to ConA-induced lymphoblast cells but LAK cells did have some cytotoxicity to the normal cells. The cytotoxicity of TILs to B 16 melanoma cells was reduced by monoclonal antimelanoma antibodies (M2590 and M562) which can block the activity of antimelanoma CTL, suggesting TILs contained high level of CTL activity. TILs were found to be more effective in their therapeutic potency in vivo on a percell basis than were LAK cells. These results indicate that TILs are more suitable to the adoptive immunotherapy of turn or as effector cells than LAK cells.
ABSTRACT
We have shown that tumor-infiltrating lymphocyte (TIL) cultured in interleukin-2 (IL-2) acquired a potent antitumor activity and had target cell specificity.TIL exhibited higher cytotoxicity to autologous tumor cells than that of LAK cells grown under identical conditions (P0.05), so that it is possible to treat recurrent and unresectable tumor using TIL periodically.