Parental Transfer of the Antimicrobial Protein LBP/BPI Protects Biomphalaria glabrata Eggs against Oomycete Infections.

Olga Lucia Baron (1) , Pieter van West (2) , Benoit Industri (3) , Michel Ponchet (3) , Géraldine Dubreuil (3) , Benjamin Gourbal (4) , Jean-Marc Reichhart (1) , Christine Coustau (5)

1 RIDI - UPR 9002 - Réponse immunitaire et developpement chez les insectes
2 Oomycete Laboratory
3 IRBI - Institut de recherche sur la biologie de l'insecte
4 2EI - Ecologie et évolution des interactions [2011-2014]
5 IBSV - Interactions Biotiques et Santé Végétale

Vertebrate females transfer antibodies via the placenta, colostrum and milk or via the egg yolk to protect their immunologically immature offspring against pathogens. This evolutionarily important transfer of immunity is poorly documented in invertebrates and basic questions remain regarding the nature and extent of parental protection of offspring. In this study, we show that a lipopolysaccharide binding protein/bactericidal permeability increasing protein family member from the invertebrate Biomphalaria glabrata (BgLBP/BPI1) is massively loaded into the eggs of this freshwater snail. Native and recombinant proteins displayed conserved LPS-binding, antibacterial and membrane permeabilizing activities. A broad screening of various pathogens revealed a previously unknown biocidal activity of the protein against pathogenic water molds (oomycetes), which is conserved in human BPI. RNAi-dependent silencing of LBP/BPI in the parent snails resulted in a significant reduction of reproductive success and extensive death of eggs through oomycete infections. This work provides the first functional evidence that a LBP/BPI is involved in the parental immune protection of invertebrate offspring and reveals a novel and conserved biocidal activity for LBP/BPI family members.

Domaines: Evolution [q-bio.PE]

Olga Lucia Baron, Pieter van West, Benoit Industri, Michel Ponchet, Géraldine Dubreuil, et al.. Parental Transfer of the Antimicrobial Protein LBP/BPI Protects Biomphalaria glabrata Eggs against Oomycete Infections.. PLoS Pathogens, 2013, 9 (12), pp.e1003792. ⟨10.1371/journal.ppat.1003792⟩. ⟨hal-00938929⟩