Abstract
Subcutaneous inoculation of living Echinococcus granulosus protoscolices (PSC) caused blastic transformation in local lymph node cells (LNC). The effect was maximal seven days post-infection (p.i.), had declined by day 21, and was prevented by killing the PSC prior to inoculation. LNC from inoculated mice also showed marked enhancement of blastogenesis in response to a secondary stimulation by live PSC in vitro. This secondary reaction occurred after exposure to living or killed PSC. There was generally enhanced reactivity to T- and B-cell mitogens at day 7. Phytohaemaggluti-nin was exceptional in that the killed parasite caused early changes in reactivity as above, but the live parasite induced a rise at 56 days p.i. It is concluded that E. granulosus may cause a determinate change in T-cell function.