THE FUNDAMENTAL PROPERTIES OF THE FIBROBLAST AND THE MACROPHAGE : IV. THE MALIGNANT FIBROBLAST OF JENSEN XXXX .

@entity242 @entity5 @entity7579 @entity3971 @entity1573 @entity35 @entity291
1. A pure strain of fibroblasts has been isolated from the Jensen @entity35 @entity242 . The cells give rise to @entity5 on transplantation into animals and during several months of life in vitro have maintained their malignancy unchanged. 2. The malignant cells are generally coarser and more refringent than normal cells. They possess the cytological characteristics of fibroblasts without showing any morphological abnormality. They can be considered as healthy cells. The texture of their colonies is looser than that of normal fibroblasts and @entity242 No. 10 fibroblasts. Their residual activity does not differ markedly from the normal. They proliferate unlimitedly in a nutrient medium. 3. They liquefy the fibrin of @entity35 plasma and turn @entity3971 red golden yellow. They do not liquefy the fibrin of @entity1573 plasma. 4. They multiply in @entity1573 embryo juice, @entity291 liver digest, and also in rat serum. Their growth activity is increased by the presence of bone marrow. 5. The unlimited growth of @entity7579 within the body may possibly be attributed to the ability of the fibroblasts to maintain themselves upon the substances present in rat serum. This property itself probably depends upon the increased enzyme activity of the cells.
