The immunomodulation of inducible hydrogen sulfide in Pacific oyster Crassostrea gigas

•The expression of CgCSE mRNA in hemocytes increased after LPS treatment.•THC increased after LPS treatment and this increase was enhanced by PAG.•Phagocytic activity increased after LPS treatment, which was inhibited by PAG. Hydrogen sulfide (H2S) is an important gasotransmitter, which plays indispensable roles in cardiovascular, nervous and immune systems of vertebrates. However, the information about the immunomodulation of H2S in invertebrates is still very limited. In the present study, the temporal expression profile of cystathionine γ lyase in oyster Crassostrea gigas (CgCSE) was investigated after the oysters were stimulated by lipopolysaccharide. The expression levels of CgCSE mRNA transcripts in hemocytes increased significantly at 12h (1.31-fold of the PBS group, P