Related Experiment Videos
Antitumor activity of Toxoplasma lysate antigen against methylcholanthrene-induced tumor-bearing rats
K Miyahara1, N Yokoo, H Sakurai
1Department of Veterinary Clinical Radiology, Obihiro University of Agriculture and Veterinary Medicine, Hokkaido, Japan.
Abstract:
Growth of the tumor autoinduced by 20-methylcholanthrene (MC) in rats was inhibited after administration of Toxoplasma lysate antigen (TLA). The antitumor activity of TLA was most obvious in the early stage of tumoral growth. When TLA was administered to rats before the appearance of tumour, tumor formation was delayed slightly. Histopathological studies revealed dense growths of spindle tumor cells in untreated control rat, while enlarged central necrosis with the infiltration of lymphocytes and neutrophils was apparent in TLA-treated rats. According to the immunohistological examination of tumor tissue with anti-Thy-1 antibody, the rats treated with TLA showed large Thy-1 positive granular cells, whereas the untreated rats indicated only a few small Thy-1 positive cells. These observations indicate that TLA is a useful modifier of biological responses to MC-induced tumors.
Insights
Toxoplasma lysate antigen (TLA) demonstrated antitumor activity against 20-methylcholanthrene-induced tumors in rats. TLA treatment led to tumor necrosis and increased Thy-1 positive cells, suggesting a role in modifying biological responses.
Area of Science:
- Immunology
- Oncology
- Parasitology
Background:
- 20-methylcholanthrene (MC) is a chemical carcinogen used to induce tumors in experimental models.
- Toxoplasma lysate antigen (TLA) is derived from the parasite Toxoplasma gondii and has immunomodulatory properties.
Purpose of the Study:
- To investigate the effect of Toxoplasma lysate antigen (TLA) on the growth of 20-methylcholanthrene (MC)-induced tumors in rats.
- To evaluate the antitumor activity and biological response modification by TLA.
Main Methods:
- Tumor induction in rats using 20-methylcholanthrene (MC).
- Administration of Toxoplasma lysate antigen (TLA) at different stages of tumor development.
- Histopathological analysis of tumor tissues.
- Immunohistochemical examination using anti-Thy-1 antibody.
Main Results:
- TLA administration inhibited the growth of MC-induced tumors, particularly in the early stages.
- Pre-treatment with TLA delayed tumor formation.
- Histopathology showed increased central necrosis and infiltration of lymphocytes/neutrophils in TLA-treated tumors.
- Immunohistochemistry revealed an increase in Thy-1 positive granular cells in TLA-treated rats.
Conclusions:
- Toxoplasma lysate antigen (TLA) exhibits significant antitumor activity against chemically induced tumors.
- TLA modulates the host's biological response, leading to tumor regression and altered cellular composition.
- TLA shows potential as a therapeutic agent for modifying responses to carcinogen-induced tumors.