Xanthan Gum as an Adjuvant in a Subunit Vaccine Preparation against Leptospirosis
Figure 4
The protective effect of immunization against lethal challenge in a hamster model. Nine- to ten-week-old hamsters were challenged with an intraperitoneal inoculum of 1.3 × 103 leptospires 14 days after the second immunization (day 28). ((a)–(c)) Experiment number 1. (d) Experiment number 2. The survival conferred by rLigANI-alhydrogel against the lethal challenge was statistically significant (). The same phenomenon occurred using rLigANI-xanthan and rLigANI-CpG-xanthan as immunogens. The protective effect of immunization using rLigANI-CpG was not significantly different from the negative control group (). Fifty micrograms of rLigANI, 0.5% xanthan (w/v), and 10 μg CpG were used. Survival curves were compared using log-rank analysis (Mantel Cox test). Bacterin: heat-killed whole-leptospires.
