Fig 1. Experimental design and timeline of immunizations and sample collection.
CD-1 female mice were immunized by subcutaneous injections (100 μl, arrows) two weeks apart at day 1 (D1) and day 14 (D14) as well as at day 28 (D28), for mouse group 3 only. CD-1 mice were divided into 6 groups (n = 5 mice per group), see the Materials and Methods section. Group 1 (SCV Inac) received the heat-inactivated S. aureus ΔvraGΔhemB; group 2 (SCV Live), received the live-attenuated S. aureus ΔvraGΔhemB; group 3 (SCV Live 3), received the same regimen as group 2, but with an additional boost immunization 2 weeks after the 2nd immunization as illustrated in purple on this timeline; group 4 (SCV Inac + J5), received a combination of the heat-inactivated S. aureus ΔvraGΔhemB and the heat-inactivated E. coli J5; group 5 (SCV Live + J5), received a combination of the live-attenuated S. aureus ΔvraGΔhemB and the heat-inactivated E. coli J5; and group 6 received only PBS (non-vaccinated control group). The boxes identify the tests performed for serum and spleen samples taken at the indicated time points (X).