Venomic and F(ab')₂ antivenomic studies of Bothrops alternatus venom proteins

In this study, using a proteomic approach, we performed the venomic characterization of B. alternatus venom proteins. The venom comprises toxins from eleven protein families and the main identified included PIII-SVMP (27.32%), PII-SVMP (12.33%), Disintegrin-SVMP (10.26%), SVSP (8.80%), PLA2 (6.85%), BBP/C-NP (4.85%), CRVP (4.87%), CTL (6.80%), LAAO (4.14%), SVGF (1.90%), VPA (1.64%), PDE (0.07%), and an unidentified percentage (11.64%). Antivenomic analysis showed that both F(ab')₂ antivenoms recognized all venom proteins but had low affinity for small peptides like BPP. The BIOL antivenom demonstrated a binding capacity of 56.92 mg/g F(ab')2, while the INPB antivenom showed a significantly higher binding capacity of 124.78 mg/g F(ab')2. These results align with in vivo studies, where the antivenom potency was 63.28 mg/g F(ab')2 and 129.38 mg/g F(ab')2 for BIOL and INPB, respectively. This study highlights the value of third-generation antivenomics in characterizing antivenoms used against B. alternatus envenomation and confirms the effectiveness of these two antivenoms in treating snakebites caused by B. alternatus. In conclusion, this study reports for the first time a comparative analysis of the venomics and antivenomics of two antivenoms used in Argentina for the treatment of B. alternatus snake bites, integrating both in vitro and in vivo approaches.