We have investigated specific immune responses in BALB/c mice with exp
erimentally induced secondary hydatidosis. Following intraperitoneal i
noculation of brood capsules containing Echinococcus granulosus-protos
coleces, the course of the infection was followed for 513 clays. The s
era of the mice were screened for the presence of a number of cytokine
s, and for specific antibodies. During the first 129 days of infection
, high levels of cytokines TNF alpha, IL-alpha, IFN-gamma, IL-6, and I
L-10 and specific IgG1 and IgG3 isotypes were detected, as compared to
uninfected controls. The levels of IgM and IgG2a were slightly increa
sed following infection, and remained elevated throughout the period o
f observation. The levels of IL-1 alpha and specific immunoglobulin of
all isotypes except IgM and Igc2a, were significantly decreased 103 d
ays post infection (p.i.), whereas TNF alpha was sharply decreased 129
days p.i. During the period of 129 to 209 days of infection there was
an increase in secreted IL-10, and a slow decrease in the levels of I
L-6 and IFN gamma. Levels of IgM, IgG, IgG1, and IgG2a plateaud during
this period, whereas IgG3 and TNF alpha showed a peak at day 190 p.i.
These data suggest the induction of Th2 antibody-mediated immunity wi
th a parallel expansion of Th1-mediated inflammatory responses as impo
rtant mechanism of host defence against the metacestode.