Journal Article

CsBAFF, a Teleost B Cell Activating Factor, Promotes Pathogen-Induced Innate Immunity and Vaccine-Induced Adaptive Immunity

Yun Sun, Li Sun

2015

Overview

B cell activating factor (BAFF) is a member of the tumor necrosis factor family that is known to play an important role in B cell activation, proliferation, and differentiation in mammals. However, studies of BAFF in teleosts are very limited and its function, in particular that under in vivo conditions, is essentially unknown. In this study, we conducted in vivo as well as in vitro functional analyses of a BAFF homologue (CsBAFF) from the teleost fish tongue sole (Cynoglossus semilaevis). CsBAFF is composed of 261 residues and shares moderate sequence identities with known BAFFs of other teleosts. CsBAFF expression was most abundant in immune organs and was upregulated during bacterial infection. Purified recombinant CsBAFF (rCsBAFF) bound to tongue sole lymphocytes and promoted cellular proliferation and survival. The results of an in vivo study showed that CsBAFF overexpression in tongue sole significantly enhanced macrophage activation and reduced bacterial infection in fish tissues, whereas knockdown of CsBAFF expression resulted in increased bacterial dissemination and colonization in fish tissues. Furthermore, vaccination studies showed that CsBAFF enhanced the immunoprotection of a DNA vaccine and augmented the production of specific serum antibodies. Taken together, these results provide the first in vivo evidence to indicate that teleost BAFF is an immunostimulator that significantly contributes to the innate antibacterial immune response and vaccine-induced adaptive immune response.

• Publisher: Public Library of Science (PLoS),Public Library of Science
• Subject: Adaptive Immunity / Amino Acid Sequence / Analysis / Animal tissues / Animals / Antibodies / Antibodies, Bacterial / Antibodies, Bacterial - blood / B cells / B-Cell Activation Factor Receptor / B-Cell Activation Factor Receptor - genetics / B-Cell Activation Factor Receptor - immunology / B-Lymphocytes / B-Lymphocytes - drug effects / B-Lymphocytes - immunology / B-Lymphocytes - microbiology / Bacteria / Bacterial diseases / Bacterial infections / Bacterial Vaccines / Bacterial Vaccines - administration & dosage / BLyS protein / Cell activation / Cell Proliferation / Cell Survival / Cell Survival - immunology / Colonization / Dendritic cells / Deoxyribonucleic acid / DNA / DNA vaccines / Edwardsiella tarda / Edwardsiella tarda - immunology / Enterobacteriaceae Infections / Enterobacteriaceae Infections - immunology / Enterobacteriaceae Infections - microbiology / Enterobacteriaceae Infections - prevention & control / Enterobacteriaceae Infections - veterinary / Epinephelus awoara / Experiments / Fish / Fish Diseases / Fish Diseases - immunology / Fish Diseases - microbiology / Fish Diseases - prevention & control / Fish Proteins / Fish Proteins - genetics / Fish Proteins - immunology / Flatfishes / Flatfishes - immunology / Gene Expression Regulation / Genetic aspects / Health aspects / Homology / Immune response / Immune system / Immunity / Immunity, Innate / Immunoglobulins / In vivo methods and tests / Infections / Innate immunity / Laboratories / Ligands / Lymphocytes / Lymphocytes B / Macrophage Activation / Macrophage Activation - drug effects / Macrophages / Macrophages - drug effects / Macrophages - immunology / Macrophages - microbiology / Marine biology / Medicine / Molecular Sequence Data / Organs / Physiological aspects / Proteins / Q / R / Recombinant Proteins / Recombinant Proteins - genetics / Recombinant Proteins - immunology / Research Article / Science / Sequence Alignment / Sequence Homology, Amino Acid / Sole / Spleen / Studies / Tumor necrosis factor-TNF / Vaccination / Vaccines / Vaccines, DNA / Vaccines, DNA - administration & dosage / Zebrafish