Polysaccharide effects simulating hypersensitivity responses in the rabbit

¹ Department of Biology, Wilkes College, Wilkes-Barre, Pennsylvania

The intravenous administration of specific polysaccharides (glycogen, amylodextrin, amylopectin) to rabbits resulted in changes in levels of circulating eosinophils and heterophil (polymorphonuclear) leukocytes over a 24-hr period. These were associated with the development of corresponding cell infiltrations within pulmonary vascular and perivascular tissue and spleen and less consistently in liver and myocardium. Features of hematologic and tissue inflammatory cell responses resembled those effected by antigen-antibody union. However, these developments could not be related to the possible participation of the polysaccharide in immune reactions by reason of natural serum antibody content: a) preformed precipitins to corresponding administered polysaccharides, or b) isoagglutinins to related blood group substance. Neither hypersensitivity nor polysaccharide effects were prevented by chemical antagonists of histamine release.

Key Words: rabbit leukocyte (heterophil and eosinophil) responses to polysaccharides • hypersensitivity reactions

Submitted on January 8, 1964