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Biomedical subjects

R K Bower

Publications and source records attributed to R K Bower.

8 recordsLinked to original sources
PubMed1988

Responses of regressor and progressor lines of chickens to intracerebral inoculations of Rous sarcoma virus.

Two-day-old chickens of the Arkansas B1 progressor (Pr) line and the B1 regressor (R) line were inoculated intracerebrally with three dilutions of Rous sarcoma virus. Chickens that died between 7 and 42 days postinoculation were examined for lesions attributable to Rous sarcomas. Mortality was 93% for the progressor chickens as compared with 65% for the regressor chicken. Macroscopic lesions were found on the head in 64 chickens, as hemorrhage in the brain in 38, on the heart in 15, on the liver in 9, and in the parenchyma of the brain in one chicken, from a total of 117 chickens inoculated. Surviving chickens were inoculated in the wingweb with Rous sarcoma virus. Of the progressor line chickens three of four developed tumors and two died. The third chicken exhibited abnormal neurological behavior. Of the regressor line, 15 of 20 were immune and of the five that developed tumors, four had complete regressions. The fifth chicken also showed neurological abnormality. The two chickens with neurological dysfunction were sacrificed, and their histopathology examinations revealed lesions in the brain with features belonging to Rous sarcomas, paralleling those reported for other types of sarcomas.

Animals↗
PubMed1982

Immunologic response in chickens from different genetic lines to Rous sarcoma virus.

Twelve young chickens of the Tumor Progressor and Tumor Regressor Lines were studied in respect to their humoral immunologic response to challenge with Rous sarcoma virus via inoculation into the wing web. On day 1, prior to virus inoculation and on days 10, 15, and 20 after injection of virus, the birds were bled and their serums tested for the presence of anti-RSV factors by standard procedures of serum-neutralization tests. From the conducting of statistical analyses of the data, it was determined that a strong association occurs between an early, increasing, and sustained presence of biologically active anti-RSV factors in the blood of the chicken and its ability to effect complete regression of the Rous sarcoma.

Animals↗
PubMedDate not supplied

The leukocyte response of Japanese quail to Rous sarcoma virus-induced tumors.

In male Japanese quail, different circulating leukocyte responses were observed for progressors (birds developing a massive tumor that persisted throughout the experiment) and regressors (birds developing a tumor that gradually disappeared) after initial challenge with Rous sarcoma virus (RSV). Blood was sampled before and at weekly intervals postinoculation. Blood smears were prepared and stained with Diff Quik, and a light microscope (1000 x) was used in a direct count of 50 fields. Leukocytes were classified as heterophils, lymphocytes, monocytes, or eosinophils. The significant increase (P < 0.05) in total leukocytes at 14 days in regressors and progressors was consistent with the increase in tumor growth. The regressors' individual percentage of leukocytes did not deviate from control values, whereas the progressors' percentages of heterophils and monocytes were significantly higher (P < 0.05) and of lymphocytes significantly lower (P < 0.05) than those of controls by 14 days postinoculation. Indicative of this was the progressors' heterophil to lymphocyte ratio, which was significantly higher (P < 0.05) than that of controls 14 days post RSV challenge and remained elevated throughout the experiment. These findings suggest that the progressors' immune response is suppressed by proliferation of malignant cells. Therefore, the heterophil to lymphocyte ratio may be used in addition to tumor size to identify those birds that will regress RSV-induced tumors.

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