Therapeutic effects of Toxoplasma lysate antigen on 20-methylcholanthrene-induced BALB/c mouse tumors.
Therapeutic effects of Toxoplasma lysate antigen (TLA) were studied in mice bearing the tumor in the second passage of 20-methylcholanthrene (MC)-induced tumor cells. Intramuscular administration of TLA 7 days after the tumor-cell inoculation caused apparent inhibition of the tumor growth on day 14. The second treatment facilitated the therapeutic effects. Intravenous transfer of spleen cells prepared from TLA-sensitized mice into tumor-bearing mice also represented the growth inhibitory effects. Prominent effects were seen when the transferred cells were prepared 5 days after sensitization of donor animals. The inhibitory effects were absent in the groups transferred only the adherent cells or the non-adherent cells prepared from sensitized mice. The strongest inhibitory effect was observed in the group to which both adherent and non-adherent spleen cells were transferred simultaneously from sensitized mice. In in vitro experiments, spleen cells obtained from sensitized mice showed cytolytic effect on P-815 or YAC-1 cells after the secondary stimulation in vitro with TLA. Large non-adherent cells containing densely packed granules were induced when cultured with the adherent cells obtained from sensitized mice. These results revealed that TLA can inhibit the growth of the chemically-induced transplantable tumors by activation of adherent and non-adherent spleen cells.
Miyahara
K
K
Department of Veterinary Clinical Radiology, Obihiro University, Hokkaido, Japan.
Honda
U
U
Tose
S
S
Sakurai
H
H
Igarashi
I
I
Saito
A
A
Hirose
T
T
Suzuki
N
N
D000818:Animals; D000953:Antigens, Protozoan / Q000627:therapeutic use*; D002448:Cell Adhesion; D002478:Cells, Cultured; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009368:Neoplasm Transplantation; D009374:Neoplasms, Experimental / Q000628:therapy*; D012878:Skin Neoplasms / Q000628:therapy*; D013154:Spleen / Q000166:cytology / Q000276:immunology*; D014122:Toxoplasma / Q000276:immunology*
D000953:Antigens, Protozoan