Figure 2: Induction of humoral immune response induced by Leptospira OMVs. OMVs specific total serum IgG was measured by indirect ELISA as described in Section 2 (OD630=0.1). Hamsters were immunized with PBS (negative control) or OMVs. Sera were collected via the saphenous vein on day 0; PV= pre-vaccination, day 21; 1st boost=before first boost, day 42; 2nd boost=before 2nd boost, day 63; BC=before challenge and day 84; AC=after challenge. Bars represent the mean of eight hamsters per group ± standard errors of the means. (*p-value< 0.05).