Table 2.
Vaccine strains carrying plasmid pS-SaoA confer protection against i.p. challenge with SS2 in BALB/c mice
| Groups | Genotypes | Percentage of survival (Number of mice Survival/Total)a |
|---|---|---|
| rSC0018(pS-SaoA) | ΔasdA33 | 0% (0/10) |
| rSC0018(pYA3493) | ΔasdA33 | 0% (0/10) |
| rSC0016(pS-SaoA) | ΔPcrp527::TT araC PBAD crp Δpmi-2426 ΔrelA199::araC PBAD lacI TT ΔsopB1686 ΔasdA33 | 100%** (10/10) |
| rSC0016(pYA3493) | ΔPcrp527::TT araC PBAD crp Δpmi-2426 ΔrelA199::araC PBAD lacI TT ΔsopB1686 ΔasdA33 | 0% (0/10) |
| rSC0011(pS-SaoA) | ΔPcrp527::TT araC PBAD crp Δpmi-2426 ΔrelA199::araC PBAD lacI TT ΔasdA33 | 40% (4/10) |
| rSC0011(pYA3493) | ΔPcrp527::TT araC PBAD crp Δpmi-2426 ΔrelA199::araC PBAD lacI TT ΔasdA33 | 0% (0/10) |
| BSG | NA | 0% (0/10) |
** P < 0.01 for the survival of mice immunized with rSC0016(pS-SaoA) compared with survival of mice immunized with rSC0011(pS-SaoA) or BSG.
aMice were challenged by i.p. with 25 × LD50 of SS2 at 7 weeks after immunization; This experiment was performed twice with same results. The data showed the result of the single experiment.