EFFECT OF ABLATION OF EOSINOPHILS ON IMMEDIATE-TYPE HYPERSENSITIVITY REACTIONS

  • 1 January 1979
    • journal article
    • research article
    • Vol. 38  (2) , 343-353
Abstract
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. AES and methylprednisolone ablated eosinophils from the blood and peritoneal cavity of test animals. Neither administration of AES nor methylprednisolone altered passive cutaneous or systemic anaphylactic reactions when compared to reactions occurring in control animals treated with normal rabbit serum (NRS). 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 tested. A significant reduction in histamine release was seen in AES-treated animals. Ablation of eosinophils by cortisone acetate resulted in a marked reduction in the quantity of histamine released into the peritoneal cavity following passive sensitization and antigen challenge. Histamine release following i.p. injection of compound 48/80 [p-methoxy-phenethyl methylamine] was not affected by the prior administration of AES or cortisone acetate. The stores of histamine apparently were not depleted by these agents. Eosinophils may 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, eosinophils may contribute to histamine release in immediate-type reactions.