THE DISTRIBUTION AND STABILITY OF ESCHERICHIA-COLI K88 RECEPTOR IN THE GASTROINTESTINAL-TRACT OF THE PIG

The levers of Escherichia coli K88 receptor were measured at various s ites within the pig intestinal tract using an enzyme immunoassay. The amount of receptor in samples taken from K88-adhesive phenotype animal s was found to vary widely along the length of the intestinal tract, b ut was usually highest in mucosal scrapings taken from the mid-small i ntestine. Receptor was evident in material collected near either end o f the small intestine and was not apparent in material collected from the caecum or lower bowel. The ability of receptor-containing intestin al material to react with immobilized K88 adhesin was inhibited by exp osure of the material to either trypsin or contents from the lower bow el. if the receptor-containing material was reacted with the immobilis ed K88 adhesin prior to exposure to trypsin or lower bowel contents, t he bound material remained evident for 24 to 48 h. The possible implic ations of variable receptor activity in proteolytic environments in re lation to pathogenesis and the determination of K88 phenotype in live pigs is discussed.