The bioactivity of teleost IL-6: IL-6 protein in orange-spotted grouper (Epinephelus coioides) induces Th2 cell differentiation pathway and antibody production

The cytokine networks of adaptive immunity in fish

“…In vitro, trout IL-6 is also induced by PAMPs (LPS and polyI:C), as well as by proinflammatory cytokines (IL-1b and TNF-a) [118;Wang et al,unpublished] in primary HK macrophages. The induction of IL-6 expression by LPS was also observed in vivo and in vitro in orange-spotted grouper [123].…”

“…The trout rIL-6 can enhance macrophage growth in vitro, suggesting that IL-6 produced during inflammatory events may promote macrophage proliferation locally [118]. Injection of grouper with rIL-6 up-regulated the expression of GATA3 and c-MAF in immune organs, and gave higher levels of IgM mRNA and protein, indicating a role of grouper IL-6 in the differentiation of Th2 cells and antibody production [123]. In agreement with this fugu rIL-6 increased the expression of secretory antibodies by mIgM þ B cells in vitro via STAT3 signalling [126].…”

“…IL-6 genes haves been cloned in a few teleost fish species including fugu [119], rainbow trout [120], spotted green pufferfish (Bird and Secombes, 2006;unpublished), Japanese flounder [121] sea bream [122], orange-spotted grouper [123] and Atlantic halibut Hippoglossus hippoglossus [124]. In addition both receptor subunits, IL-6Ra and gp130 have been describes in rainbow trout [125] and fugu [126].…”

Inhibitory Effect of Sargauum fulvellum Ethanolic Extract on LPS-Induced Inflammatory Reaction in RAW 264.7 Mouse Macrophages

“…IL-6 is a protein secreted by Th2 cells and macrophages and plays an important role in immune response. IL-6 regulates the proliferation and differentiation of T cells, and elicits immunoglobulin production in B cells (Chen et al, 2012). The RAW 264.7 cells were cultured in the media with LPS (1 µg/mL) alone or in combination with the extract.…”

Efficacy of a formalin-inactivated vaccine against Streptococcus iniae infection in the farmed grouper Epinephelus coioides by intraperitoneal immunization

“…The expressions of igm [23], il-1ˇ, and tnf-˛ [24] in PBLs were evaluated using RT-qPCR. ˇ-Actin [25] served as the internal control. RT-qPCR was performed using iQ SYBR Green Supermmix (Bio-Rad Laboratories), and each sample was run in triplicate.…”