RESUMEN
The effect of cell-free extracts obtained from thymocytes of 8, 18 and 23 day fibrosarcoma-bearing U rats and normal U rats on tumor growth was investigated. The results show that thymocyte extracts of 8 day tumor-bearing rats inhibit the tumor growth in implanted animals and no significant effect was found with extracts from other times, or from normal thymocytes. Some of the inhibitory activity was lost by dialysis, which led us to assume that low molecular weight substances are involved in the antitumor immune response.
Asunto(s)
Extractos Celulares/farmacología , Fibrosarcoma/patología , Neoplasias Experimentales/patología , Extractos del Timo/farmacología , Timo/citología , Extractos de Tejidos/farmacología , Animales , Masculino , RatasRESUMEN
1. In a study of the in vivo effects of semi-purified mouse interleukin-2 (IL-2), inflammatory activity indicated by edema and plasma protein extravasation (PPE) was detected in those fractions having IL-2 activity. 2. The molecular weight of the inflammatory factor activity from conditioned medium was 30 to 48 kDal on the basis of gel filtration on Sephadex G75. 3. The edema, characterized as maximum paw thickness, occurred at 4 h, whereas the PPE peak (measured with 125I-albumin) occurred 1.5 to 3 h after injection. 4. Both edema and PPE were inhibited by dexamethasone or indomethacin, suggesting the involvement of prostaglandins in the process. 5. This inflammatory activity may be partly responsible for some of the in vivo activities ascribed to IL-2.