tailieunhanh - Role of T lymphocytes and papain enzymatic activity in the protection induced by the cysteine protease against Schistosoma mansoni in mice

Papain, an experimental model protease, was used to decipher the protective mechanism(s) of the cysteine peptidase-based schistosomiasis vaccine. To examine the role of T lymphocytes, athymic nude (nu/nu) and immunocompetent haired (nu/+) mice were subcutaneously (sc) injected with 50 mg active papain two days before percutaneous exposure to 100 cercariae of Schistosoma mansoni. Highly significant (P 80% in dead parasite ova in the small intestine were independent of T cell activity and likely relied on the innate immune axis. To investigate the role of enzymatic activity, immunocompetent mice were sc injected with 50 mg active or E-64-inactivated papain two days before exposure to cercariae. The reductions in worm burden were highly significant (P 65% and 40% in active and inactivated papain-treated mice, respectively. Similar highly significant (P | Role of T lymphocytes and papain enzymatic activity in the protection induced by the cysteine protease against Schistosoma mansoni in mice