Live attenuated Edwardsiella ictaluri vaccines enhance the protective innate immune responses of channel catfish B cells

• Published in: Developmental and comparative immunology Vol. 109; p. 103711
• Main Authors: Kordon, Adef O., Kalindamar, Safak, Majors, Kara, Abdelhamed, Hossam, Tan, Wei, Karsi, Attila, Pinchuk, Lesya M.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Ltd 01-08-2020; Elsevier Science Ltd
• Subjects: Apoptosis; Catfish; Catfish B cells; Edwardsiella ictaluri; Innate functions; Innate immunity; Live attenuated vaccines; Lymphocytes B; Opsonization; Phagocytosis; Protection; Septicemia; Vaccines; Catfish B cells; Live attenuated vaccines; Innate functions; Opsonization; Protection; Apoptosis
• ISSN: 0145-305X; 1879-0089
• DOI: 10.1016/j.dci.2020.103711

Edwardsiella ictaluri causes enteric septicemia of catfish. Our group developed two E. ictaluri live attenuated vaccines (LAVs). However, their effects on the innate functions of catfish B cells are still unexplored. We evaluated phagocytosis and killing of wild-type (WT) E. ictaluri opsonized with sera from vaccinated fish and the survival of B cells exposed to E. ictaluri strains. We assessed phagocytosis of the opsonized WT at 30 °C and 4 °C. B cells killed the internalized E. ictaluri opsonized with sera from vaccinated fish with LAVs more efficiently than other groups at 30 °C. However, catfish B cells were unable to destroy E. ictaluri at 4 °C. Furthermore, E. ictaluri opsonized with serum from fish exposed to WT induce apoptosis and decreased live B cells numbers. Results indicate that opsonization of E. ictaluri with sera from vaccinated fish enhanced phagocytosis and killing activity in B cells and inhibited apoptotic changes in the infected B cells.
•Phagocytosis, bacterial killing and apoptosis in catfish B cells. Protective properties of live attenuated vaccines.