EFFECT OF TOXOCARA CANIS SECOND STAGE LARVAE ON THE HOST IMMUNE SYSTEM

We have studied functional alteration of immunocytes in mice following
inoculation of Toxocara canis second stage larvae. Results indicated depression
of lymphocyte blastogenesis in response to concanavalin-A,
phytohemagglutinin and allogeneic non B-cells; however, B-cell polyclonal
activation was not affected as indicated by the production of total IgG.
In contrast, frequency of antibody secreting cells was reduced. Similarly,
interleukin-1 and interleukin-2 production were not affected by Toxocara
canis infection. Furthermore, spleen cells of infected mice synthesized
more prostaglandin E than uninfected animals. This data suggests that
Toxocara canis infection induces suppression of both cell mediated and
humoral immunity; perhaps due to an increase of prostoglandin E2 production.