Protection against tumor challenge with ST40L.
(A) A20 cells (105) were administered subcutaneously to BALB/c mice with 109 CFU of ST40L (•, upper line), 109 CFU of ST (⊙, middle line), or PBS (○, lower line) being given by simultaneous oral administration. As a control, wehi-3 CD40 negative cells were treated by the administration of ST40L (▴), ST(▾), or PBS(▵), in a similar manner to that above. (B) Differing numbers of A20 cells were subcutaneously injected into BALB/c mice (40 mice for each condition) with either 109 CFU of ST40L (A20 cell number: 105, •;106, ▴;107, ▪) or PBS (A20 cell number: 105, ○;106, ▵;107, □) being given by simultaneous oral administration. (C) BALB/c mice were preimmunized with ST40L 1 week (▴), 2 weeks (▪), or 3 weeks (▾) before A20 challenge (105 SC). The survival curves were compared with simultaneous immunization with ST40L (•) or PBS (○). (D) BALB/c mice were postimmunized with ST40L 1 week (▴), 2 weeks (▪), or 3 weeks (▾) following A20 challenge (105 SC). The survival curves were compared with simultaneous immunization with ST40L (•) or PBS (○).
