Related Experiment Videos
Necrotizing activity of tumor necrosis factor: histopathological investigation using Meth A sarcoma and granulation
1Department of Pathology, National Defense Medical College, Saitama, Japan.
Abstract:
The action of tumor necrosis factor (TNF) was investigated histopathologically in mice using methylcholanthrene A (Meth A)-induced sarcomas and granulation tissue induced by autotransplantation of fragments of liver and spleen. Highly purified murine TNF caused hemorrhagic necrosis of both the tumors and the granulation tissue. Proliferation of tumor capillaries, demonstrated microangiographically, occurred 2 h after TNF administration and hyperemia of tumor vessels was obvious after 3-6 h. Hyperemia and capillary leakage were also observed in the granulation tissue 6 h after TNF injection and hemorrhage was noted in the epidermis after 12 h. These results strongly suggest that the in vivo necrotizing action of TNF is mainly related to capillary injury.
Insights
Tumor necrosis factor (TNF) causes hemorrhagic necrosis in tumors and granulation tissue by damaging capillaries. This study reveals TNF
Area of Science:
- Oncology
- Immunology
- Pathology
Background:
- Tumor necrosis factor (TNF) is a cytokine with known cytotoxic effects.
- The precise mechanism of TNF's in vivo action, particularly its effect on vasculature, requires further elucidation.
Purpose of the Study:
- To investigate the histopathological effects of murine tumor necrosis factor (TNF) on methylcholanthrene A (Meth A)-induced sarcomas and granulation tissue in mice.
- To determine the role of capillary injury in TNF-induced necrosis.
Main Methods:
- Histopathological examination of Meth A-induced sarcomas and experimentally induced granulation tissue in mice.
- Administration of highly purified murine TNF.
- Microangiographic demonstration of tumor capillary proliferation.
Main Results:
- Highly purified murine TNF induced hemorrhagic necrosis in both tumors and granulation tissue.
- TNF administration led to rapid proliferation of tumor capillaries (2 h) and hyperemia of tumor vessels (3-6 h).
- Hyperemia, capillary leakage, and epidermal hemorrhage were observed in granulation tissue following TNF injection.
Conclusions:
- The necrotizing action of TNF in vivo is primarily attributed to its detrimental effects on capillary integrity.
- TNF-induced vascular injury is a key mechanism underlying its anti-tumor and tissue-damaging effects.