Intestinal and systemic humoral immunological events in the susceptible Balb/C mouse strain after oral administration of Echinococcus multilocularis eggs

The aim of the the study was to investigate the systemic and, for the first time, the intestinal humoral events in the susceptible Balb/C mouse strain after oral administration of Echinococcus multilocularis eggs. Thirty-one mice were divided into three groups; W-2, W-8 and control group. Each mouse of the W-2 and W-8 groups was orally infected with 1,500 E. multilocularis eggs, two weeks and eight weeks before sacrifice respectively. Central gro up mice received phosphate buffer saline. Measurement of anti-E, multilocul aris and non-specific IgG, IgA and IgM, and of a transudation marker albumi n, were performed in serum and intestinal washings by a time-resolved immun ofluorometric assay. These results were complemented by microscopic examina tion of the intestinal mucosa. This infection model is well-suited to the s tudy of mucosal immunity during alveolar echinococcosis. II showed a major specific intestinal response in the early stage of the disease whereas the systemic response predominated later in the disease. Histopathological stud ies and calculation of the relative coefficient of excretion of Ig also con firmed that the presence of the parasite, even during a short period was re sponsible for a local immunological and imflammatory response and for a cha nge in mucosal permeability. Mucosal immunity could thus play a role in tol erance induction against E. multilocularis that could be a prerequisite for the subsequent development of the larvae in the liver, and for the occurre nce of the parasitic disease, alveolar echinococcosis.