抄録
The effect of partially purified rat tumor necrosis factor (TNF) was tested against 9L rat brain tumor both in vivo and in vitro. The TNF-containing serum (TNS) was produced by intravenous injection of OK432 and lipopolysaccharide (LPS). Injection of TNS significantly (p <0.05) prolonged the survival time of brain tumor-bearing rats (29.9±12.6 days after tumor cell inoculation, as compared to 20.8±4.4 days in the untreated group).
In the in vitro assay, medium containing 50% TNS significantly decreased the viability of 9L brain tumor cells, by 57.6%, 50.0%, and 57.0% at 3, 5, and 7 days after the beginning of culture, respectively. TNS also displayed significant inhibition of cell growth, indicating a cytostatic effect. To verify TNF activity, TNS was partially purified by means of the DEAE-Sephadex A 50 batch ion exchange method and Sephadex G 200 column chromatography. Four fractions were tested in TNF-sensitive L (S) cells, TNF-resistant L (R) cells, and 9L brain tumor cells. Fraction 4 of TNS demonstrated 37.5%, 88.1 %, and 43.2% cell viability against L (S), L (R), and 9L cells, respectively. On the other hand, fraction 4 of normal rat serum showed 87.5%, 87.8%, and 82.2% cell viability, respectively. These results strongly suggest the presence of TNF in the TNS produced by OK432 and LPS.
