Figure 5.

Active immunity enhances systemic bacterial clearance and confers protection from lethal doses of E. faecalis infection. For active immunization studies, total CFU was recovered after 48 and 96 hours post-infection, respectively, from (A) spleen, (B) peritoneal cavity, and (C) kidneys of mice immunized with antigen cocktail (EfaA + AdcA + AdcAII) suspended in Freud’s adjuvant. PBS suspended in Freud’s adjuvant is used as immunization control. Data points represent groups of 10 infected mice using two biological replicates of E. faecalis OG1RF. After running ROUT standard 1% outlier test, statistical analysis was performed using Mann–Whitney test. ** P ≤ 0.01, *** P ≤ 0.001, ^****  P ≤ 0.0001. (D) Percentage survival of mice immunized with either antigen cocktail (EfaA + AdcA + AdcAII) or their single-antigen counterparts 72 hours post-infection with lethal dose of E. faecalis OG1RF. Mice immunized with PBS suspended in Freud’s adjuvant are used as immunization control. Each curve represents a group of 20 mice. Data points represent average of 2 biological replicates. Statistical analysis was performed using Log-rank (Mantel–Cox) test. * P ≤ 0.05.