Refractory phagocytosis by chicken thrombocytes during aflatoxicosis

The percentage phagocytosis of chicken thrombocytes was insensitive to dietary aflatoxin (10 microgram/g diet) while the mean phagocytosis was slightly but significantly (P less than .05) reduced by 5 or 10 microgram/g but not lower levels. Thrombocytic phagocytosis was dependent on a heat sensitive serum factor which is not affected during aflatoxicosis. These findings contrast with reports that other phagocytic types such as heterophils, macrophages, and monocytes are sensitive to low levels (e.g., .625 microgram/g) of dietary aflatoxin.

Impairment of phagocytosis in chicken monocytes during aflatoxicosis

Graded doses of dietary aflatoxin (0, .625, 1.25, 2.5, 5.0, and 10.0 microgram/g) were tested for their effect on the phagocytic and locomotive capacities of monocytes from chicken blood. The percentage and mean phagocytic activites were decreased significantly (P less than .05) at 2.5 microgram/g and above and at 1.25 microgram/g and above, respectively. Both the directed and undirected locomotion of monocytes were impaired significantly (P less than .05) at 2.5 microgram/g and above. A serum factor with the heat sensitivity of complement and which was required for optimal phagocytosis by monocytes also was reduced in activity during aflatoxicosis. Thus, the circulating element of the mononuclear phagocyte series has reduced capacity to perform its role in host defense during aflatoxicosis.

Ochratoxin A-induced iron deficiency anemia

Ochratoxin A at 8 micrograms per g of diet, but not at lower doses, fed to chickens from 1 day to 3 weeks of age resulted in significantly (P less than 0.05) decreased packed blood cell volume and hemoglobin concentration without altering the number of circulating erythrocytes. Serum iron and percentage of transferrin saturation were lowered at 4 and 8 micrograms/g. Therefore, anemia was characteristic of severe ochratoxicosis of young chickens, and the anemia was categorized as a hypochromic-microcytic anemia of the iron deficiency type. These data indicate that ochratoxin A by itself does not cause hemorrhagic anemia syndrome of chickens and that an anemia caused by a nutritional deficiency can be elicited by a mycotoxin.

In vitro propagation of prostate adenocarcinoma cells from rats

Two rat adenocarcinomas were physically dispersed and propagated in vitro. Epithelial and fibroblast cell lines were cloned from them and the monolayer cell lines derived therof were further characterized. The cells produced acid phosphatase in early in vitro cell passages, and later they turned negative. Fibroblast-like cells produced no tumors when implanted in syngeneic Lobund Wistar rats, but as few as 10 epithelial cells produced metastasizing adenocarcinomas in them. A third prostate tumor has yielded a line of epithelial cells which reproduced the original tumor type in inoculated rats, but the cells have not yet been characterized. Rat prostate adenocarcinomas provided a useful model system for in vitro and in vivo studies on prostate cancer and on metatasis.

Investigations on prostatic adenocarcinomas in rats

Metastatic prostate adenocarcinomas, derived from aging germfree Wistar rats, have been propagated in rats and in tissue culture. A protocol has been developed and demonstrated for assay of treatments which retard or which accelerate the rate and extent of tumor growth and of metastasis in tumor-bearing rats. The pattern of spread has been retarded by cyclophosphamide, aspirin, indomethacin, and Corynebacterium parvum. The spread pattern has been accelerated by oral administrations of sodium barbiturate.