Fig. 7
Shigella challenge. a Visible diarrhea was observed in control/blank NP group (left image) and fecal pellet was observed in all immunized groups (right, representative image), 4 h post intraperitoneal challenge with heterologous Shigella. b Percentage loss of weight in the treated groups 12 h post challenge (Kruskal–Wallis test, Dunn’s multiple comparisons posttest, ****p < 0.0001 indicates statistically significant difference of the treated groups with respect to control). c Percentage survival of the treated groups against intraperitoneal challenge with heterologous S. flexneri 2a, 1 × 109 CFU (Log Rank test ***p = 0.0001 indicates statistically significant difference with respect to control) (n = 14). d, e Passive immunity analysis—mice immunized with NV1 were bred to produce progeny after 3rd dose of immunization (28 days) and the obtained 5 day old neonates were orally challenged with S. flexneri 2a, 5 × 108 CFU (Log Rank test **p = 0.0075 indicates statistically significant difference with respect to control) (n = 8)