Localization of Radioiodinated Rat Fibrinogen in Transplanted Rat Tumors2

Abstract

Radioiodinated rat fibrinogen localized in three different transplantable rat tumors during the initial inflammatory reaction of the host to the implant and during the rapid growth stage of the tumor. Extent of localization during inflammation paralleled the amount of tissue inflamed; extent of localization during subsequent tumor growth paralleled rate of tumor growth. In the Murphy-Sturm lymphosarcoma at its most vigorous state (10 gm., 8 days after implantation), 40 percent of the intravenously injected fibrinogen localized in the tumor in 6 hours as the tumor grew nearly two more grams. Disappearance of labeled fibrinogen from the tumors was slower than that of labeled fibrinogen from the blood, but when antifibrin antibodies were present, the disappearance of labeled fibrinogen from both was markedly hastened without a parallel disappearance of antibody.