Studies on mortality in chick embryos resulting from implantation of whole blood and blood fractions from patients and animals with neoplastic disease.

It was observed previously in these laboratories1 that cells and cell fractions from human and animal leukemia when introduced onto the chorioallantoic membranes of embryonated chick eggs produced severe toxicity to embryonic and extra-embryonic tissues, with mortality in a high percentage (50-100%) of inoculated eggs. In marked contrast to these observations, similarly implanted cells and cell fractions of normal origin or fragments of neoplastic tissues were relatively innocuous in eggs, causing little in the way of toxicity and a low percentage of embryonic deaths (0-30%). The present studies were designed to determine whether whole blood and blood fractions from patients and animals with neoplasms (other than leukemia) were as effective as leukemic cells and cell fractions in producing high mortality of chick embryos. Materials and Methods.-Embryonated White Leghorn chicken eggs were incubated at 380C and were 6-9 days old when implanted. At least 7 to 10 eggs were used in testing each specimen. Implants were made in eggs by inserting a small fragment of solid tissue or 0.1 ml of blood, plasma, or other materials studied on the chorioallantoic membrane (CAM). A detailed description of the experimental methods employed for inoculation of blood, fractions, cell and tissue specimens onto the CAM was reported elsewhere.' Gross observations were made daily and experiments were terminated after 7 days. All specimens were subjected to appropriate bacteriological examinations, and specimens which were found to be contaminated were eliminated from further consideration, since such contamination invariably resulted in death of the embryo. Specimens studied included heparinized human leukemic whole blood, leucocytes, plasma, and bone marrow (obtained by sternal aspiration); whole blood, leucocytes, plasma, and tissue from patients with malignant and benign tumors; whole blood, leucocytes, and plasma from normal human sources, or from patients without indication of neoplastic disease; and a variety of bloods and tumors from hamsters and mice. Because fluctuation in mortality of the untreated chick embryo exists, specimens from patients free from cancer always were tested.in eggs simultaneously with those from patients with cancer. Results.-These studies indicated that although tumor tissues per se (other than leukemia) were generally not toxic to chick embryos, bloods from cancer patients and animals with metastasizing cancers were extremely toxic. A comparison of the toxicity in chick embryos of blood from patients with and without neoplastic disease (Table 1) revealed that blood from 186 of 187 patients with neoplastic disease tested