Biomedical subjects
G M Olson
Publications and source records attributed to G M Olson.
The effect of antiserum to eosinophils and susceptibility and acquired immunity of the guinea-pig to trichostronglyus colubriformis.
There is much experimental evidence to suggest that eosinophils are important in resistance to parasitic infection. We tested this hypothesis by treating guinea-pigs with rabbit anti-eosinophil serum (AES) and determining the effect of treatment on susceptibility and acquired immunity to Trichostrongylus colubriformis. The treatment markedly reduced the number of eosinophils in peripheral blood and in the small intestine. The number of T. colubriformis present after initial infection and after a second infection was determined in animals treated with AES and in control animals. Administration of AES to guinea-pigs significantly increased the susceptibility of the animals to initial infection with T. colubriformis larvae; the number of worms recovered was nearly doubled. Similarly- administration of AES resulted in a significant diminution of acquired immunity to a secondary infection. These results are consistent with the view that eoxinophils are important in susceptibility and acquired immunity to infection with T. colubriformis in the guinea-pig. Because T. colubriformis infection is confined to the intestinal tract, our results also suggest that eosinophils may be involved in resistance to parasites at the level of the intestinal mucosa.
Eosinophils and hypersensitivity reactions.
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The effect of ablation of eosinophils on immediate-type hypersensitivity reactions.
The effect of ablation of eosinophils on hypersensitivity reactions in guinea-pigs was tested by administration of rabbit antiserum to the eosinophil (AES) and by administration of glucocorticoids. Both AES and methylprednisolone ablated eosinophils from the blood and peritoneal cavity of test animals. Neither administration of AES nor methylprednisolone, however, altered passive cutaneous or systemic anaphylactic reactions when compared to reactions occurring in control animals treated with normal rabbit serum (NRS). Also there was no consistent effect of AES on the intensity of the Arthus reaction. The effect of ablation of eosinophils on histamine release in the passively sensitized peritoneal cavity of the guinea-pig was also tested. In five experiments a significant reduction in histamine release was seen in AES-treated animals. Ablation of eosinophils by cortisone acetate also resulted in a marked reduction in the quantity of histamine released into the peritoneal cavity following passive sensitization and antigen challenge. Histamine release following intraperitoneal injection of compound 48/80 was not affected by either the prior administration of AES or cortisone acetate, suggesting that the stores of histamine were not depleted by these agents. Overall these results suggest that eosinophils do not play a prominent role in initial expression of immediate-type hypersensitivity reactions where the density of these cells in tissues is low. When present in larger numbers, however, eosinophils may contribute to histamine release in immediate-type reactions.
Reactivity of rabbit antiserum to guinea pig eosinophils.
Although the eosinophil has been recognized as a distinctive cell type for almost 100 years, the major functions of these cells remain unknown. As an approach to defining these functions we have treated guinea pigs with rabbit antiserum to eosinophils (AES) in an attempt to ablate these cells from tissues. Rabbits were immunized thrice with purified eosinophils and the antisera were absorbed with peripheral blood cells from guinea pigs made eosinopenic with methyprednisolone to remove antibodies reactive with serum proteins and erythrocytes. The resulting sera reacted strongly with eosinophils in cytotoxicity tests and had weak or no reactivity with neutrophils. However, absorption of AES with purified neutrophils removed antieosinophil activity. Intraperitoneal injection of potent AES into guinea pigs resulted in complete absence of eosinophils from the peripheral blood and from the peritoneal cavity with only transient or no reduction in circulating neutrophils. Eosinophils were also reduced in bone marrow, spleen, and intestine. The ability of neutrophils to absorb AES activity in spite of weak reactivity in cytotoxicity tests may reflect a quantitative difference in antigenic determinants between eosinophils and neutrophils.
Processing the terms right and left: a note on left-handers.
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Asymmetries in processing the terms "right" and "left".
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Long-term correlates of children's learning and problem-solving behavior.
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