The effect of concanavalin A and wheat germ agglutinin on the ultrastructure and permeability of rat intestine. A possible model for an intestinal allergic reaction

Int Arch Allergy Appl Immunol. 1984;75(3):230-6. doi: 10.1159/000233621.


Sprague-Dawley rats were exposed to lectins, either concanavalin A (Con A) or wheat germ agglutinin (WGA). The lectins were instilled into a ligated segment of the distal small intestine together with permeability markers, fluoresceinated dextran (MW 3,000) or a mixture of differently sized polyethylene glycols (MW 400, 600 and 1,000). WGA-treated rats showed a decreased permeability to small molecules (MW less than 600) of polyethylene glycol but an increase for a larger dextran molecule (MW 3,000). These effects as well as the morphological findings might mimic the situation in patients with food allergy or celiac disease. Con A-treated rats had decreased intestinal permeability to the larger dextran molecules (MW 3,000), whereas the passage of small molecules was unaffected and the ultrastructural effects were minute. The Con A-induced changes could result from a mucotractive effect, associated with a low-grade gut allergy. These observations suggest that lectins can affect both the ultrastructure and the permeability of the intestine, in a way assumed to mimic allergic reactions to food constituents.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Concanavalin A / immunology*
  • Dextrans / urine
  • Female
  • Fluorometry
  • Intestine, Small / ultrastructure*
  • Lectins / immunology*
  • Molecular Weight
  • Permeability
  • Plant Lectins
  • Polyethylene Glycols
  • Rats
  • Rats, Inbred Strains
  • Triticum


  • Dextrans
  • Lectins
  • Plant Lectins
  • Concanavalin A
  • Polyethylene Glycols