Detection and characterization of anti-tumour effector cells in Meth-A-bearing mice treated with recombinant human interleukin 2.
When Meth-A fibrosarcoma-bearing BALB/c mice were injected subcutaneously with 10 micrograms of recombinant human interleukin 2(rIL-2) once a day for 10 days, tumour growth inhibition was in the range of 22-31% of that of the control animals. Anti-tumour effector cells against Meth-A were detected in the spleen cells of the tumour-bearing BALB/c mice injected with rIL-2, using a modified Winn-type neutralization assay with the auxiliary injection of rIL-2. To induce the strongest anti-tumour activity in this assay system, the following were necessary: 1) the effector cells were derived from tumour-bearing BALB/c mice; 2) the donors of the effector cells were injected with rIL-2; 3) the recipient mice in the Winn assay were auxiliarily injected with rIL-2 (a modified Winn assay). The anti-tumour effector activity detected in the modified Winn assay was inhibited by treatment with anti-CD8 or anti-asialo GM1 antibodies plus complement (C), but not completely. We supposed that at least two kinds of anti-Meth-A effector cells with different surface antigens, positive for CD8 and asialo GM1 antigens, were induced in the Meth-A-bearing BALB/c mice injected with rIL-2; these populations seemed to function independently and at least partly as anti-tumour effector cells in this tumour-host system. These spleen cells showed in vitro cytotoxicity against Meth-A cells, which are resistant to NK cells, if the activity was measured in a 24 h 51Cr-release assay in the presence of rIL-2.
Naruo
K I
KI
Biotechnology Laboratories, Central Research Division, Takeda Chemical Industries, Ltd., Osaka, Japan.
Hinuma
S
S
Shiho
O
O
Houkan
T
T
Ootsu
K
K
Tsukamoto
K
K
D000818:Animals; D005260:Female; D005354:Fibrosarcoma / Q000139:chemically induced / Q000276:immunology*; D007376:Interleukin-2 / Q000494:pharmacology*; D007694:Killer Cells, Natural / Q000187:drug effects / Q000276:immunology*; D008748:Methylcholanthrene; D051379:Mice; D008807:Mice, Inbred BALB C; D011994:Recombinant Proteins / Q000494:pharmacology
D007376:Interleukin-2; D011994:Recombinant Proteins; D008748:Methylcholanthrene