title: Ostertagia ostertagi: excretory secretory chemotactic substance from infective larvae as cause of eosinophil locomotion.
abstract: The infective (third stage) larva of Ostertagia ostertagi produced an excretory secretory substance that is chemotactic for bovine eosinophils. The eosinophil chemotactic substance was present in supernatants of larval cultures within 6 hr of incubation in Eagle's Minimum Essential Medium containing 25 mM N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid. The substance responsible for eosinophil chemotaxis has activity in small amounts, a molecular weight (MW) greater than 2000, and is heat labile at 100 C. Bovine eosinophils appeared to have a receptor for the chemotactic excretory secretory substance which is either identical or structurally similar to the previously described eosinophil chemotactic substance present in soluble third stage larval extracts. The larval substance may cause eosinophil accumulation in the abomasal tissue of cattle with ostertagiasis.
mesh_terms: D000818:Animals; D002417:Cattle; D002630:Chemotactic Factors / Q000494:pharmacology*; D002631:Chemotactic Factors, Eosinophil / Q000096:biosynthesis / Q000494:pharmacology*; D002634:Chemotaxis, Leukocyte; D004804:Eosinophils / Q000378:metabolism / Q000502:physiology; D006358:Hot Temperature; D007814:Larva / Q000378:metabolism; D008970:Molecular Weight; D010028:Ostertagia / Q000378:metabolism*
chemical_list: D002630:Chemotactic Factors; D002631:Chemotactic Factors, Eosinophil