Cytokines Induced by Edwardsiella tarda: Profile and Role in Antibacterial Immunity

Abstract

Edwardsiella tarda is a Gram-negative bacterial pathogen with a broad range of hosts, including fish and mammals. In the present study, we used an advanced antibody array technology to identify the expression pattern of cytokines induced by E. tarda in a mouse infection model. In total, 31 and 24 differentially expressed cytokines (DECs) were identified in the plasma at 6 h and 24 h post-infection (hpi), respectively. The DECs were markedly enriched in the Gene Ontology (GO) terms associated with cell migration and response to chemokine and in the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways associated with immunity, diseases, and infection. Ten key DECs, including IL6 and TNF-α, were found to form extensive protein-protein interaction networks. IL6 was demonstrated to inhibit E. tarda infection and be required for E. tarda-induced inflammatory response. TNF-α also exerted an inhibitory effect on E. tarda infection, and knockdown of fish (Japanese flounder) TNF-α promoted E. tarda invasion in host cells. Together, the results of this study revealed a comprehensive profile of cytokines induced by E. tarda, thus adding new insights into the role of cytokine-associated immunity against bacterial infection and also providing the potential plasma biomarkers of E. tarda infection for future studies.

A Non-Canonical Teleost NK-Lysin: Antimicrobial Activity via Multiple Mechanisms

“…The sequences of the siRNAs are listed in Table S3 . Gene knockdown by RNA interference was performed as described previously [ 47 ]. Briefly, FG-9307 cells were transfected with or without (control) the NKLnc-specific siR1 or siR2, or the negative control siRNA (NCS) for 24 h using Lipofectamine RNAiMAX (Invitrogen, Carlsbad, CA, USA).…”

“…Gene knockdown was verified by qRT–PCR ( Figure S2 ). The NKLnc-knockdown cells and control cells were infected with V. harveyi, as reported previously [ 47 ] with slight modification. Briefly, V. harveyi was prepared as described above and resuspended in PBS.…”