Characterization of natural antigen-specific antibodies from naïve sturgeon serum

• Published in: Developmental and comparative immunology 2020-11, Vol.112, p.103770-103770, Article 103770
• Main Authors: Yasumoto, Kyutaro, Koiwai, Keiichiro, Hiraoka, Kiyoshi, Hirono, Ikuo, Kondo, Hidehiro
• Format: Article
• Language: English
• Subjects: Affinity chromatography; Antibodies; Antibody; Antigens; Hatching; Immunoprecipitation; Lysozyme; Oncorhynchus mykiss; Salmon; Sturgeon; Trout
• ISSN: 0145-305X; 1879-0089
• DOI: 10.1016/j.dci.2020.103770

In this study, we isolated and characterized natural antibodies found in serum samples from Bester sturgeon (Huso huso × Acipenser ruthenus). Natural antibodies specifically detected hen egg lysozyme (HEL), keyhole limpet hemocyanin (KLH), and several species of pathogenic bacteria. Interestingly, we detected no antibodies with similar specificity in serum samples from rainbow trout (Oncorhynchus mykiss) or from Japanese flounder (Paralichthys olivaceus). Binding capacity of the sturgeon natural serum antibodies increased slightly at 7 months compared to 3 months after hatching. Antigen-specific antibodies against KLH, Aeromonas hydrophila and Streptococcus iniae were affinity-fractionated from naive sera of Bester sturgeon; specific detection of the corresponding antigens was observed. We conclude that Bester sturgeon are capable of generating unique natural antibodies including those that are pathogen-specific. •The sturgeon natural serum antibodies bound to various antigens.•The binding activities were increased from 3 to 7 months after hatching.•The antigen specific natural antibodies were fractionated and evaluated.