The Expression And Transformation Of Immune Factors Between Generations In Maternal Ctenopharyngodon Idella After Immune With GCRV Attenuated Vaccine And APS

Grass carp(Ctenopharyngodon idella)is an important kind of freshwater fish.Grass carp reovirus(grass carp reovirus,GCRV)is the most prominent disease which seriously restricts the grass carp farming industry sustainable development.Based on fish maternal immunity and the improvement of immune ability of grass carp by astragalus polysaccharides,in order to investigate the expression of three immune factors(IgM,C3,LSZ)in the GCRV attenuated vaccine and Astragalus polysaccharides(APS)and analyze the immune factors in offspring of the grass carp.In this study,In this study,we used ELISA,RT-qPCR and other methods to detect the 40 days of prenatal grass carp mother by inoculation of grass carp hemorrhagic disease attenuated vaccine and feeding Astragalus polysaccharide immune mother blood about Immune protein activity and gene expression level of offspring embryos and juvenile stage.The gene expression levels of three immune factors and the immune effect against GCRV infection were measured in healthy immune tissues of 2 months old fish and immunocompetence of GCRV.The results showed that the activity of Ig M,C3 and LSZ were significantly higher than those of the control group,and the activity of IgM,C3 and LSZ protein in the blood of the attenuated vaccine was significantly higher than that of the control group 3.0 times,the mRNA level was 2.5 times,2.2 times and 3.0 times higher than that of the control group.The protein activity of IgM,C3 and LSZ in the APS group was significantly higher than that in the control group,1.6 times,2.0 times,APS group IgM mRNA levels higher than the control group,but no significant difference,while C3 and LSZ mRNA were 1.9 times the control group,2.6 times.In the embryo and fry development stages,the activities of three immunogenin proteins increased first and then decreased in the embryos and larvae,and the IgM protein was significantly higher in the progeny than in the control group.The C3 and LSZ activities of the vaccine and APS immunized groups were significantly different from those in the control group at early embryos and fry hatching.The expression of IgM gene in the three groups was the highest in the early stage of development,and the expression of IgM gene in the egg,APS and APS immunized group were 2.6 times and 2.4 times of that of the control group,respectively.No IgM gene expression was detected in the 12 h embryo to 5 d larvae,but no significant difference was found in the 14 days of the larvae stage.The C3 gene was not detected in the 3 treatment groups from 3 to 12 h.LSZ gene in the three treatment groups to 6 h(gastrula stage)showed a rapid decline in the vaccine immunization group and the control group was significantly different,while the APS immunized group only in the egg and fertilized eggs and the control group was significant difference.The levels of IgM,LSZ and C3 mRNA in healthy tissues of 2-month-old fish were found to be significantly different from those of the control group in the immune tissue spleen,body kidney and head kidney,while the immunized group of IgM was only in the head kidney And the control group had significant differences.There was no significant difference in C3 and LSZ expression between the three groups.After GCRV challenge,the expression level of IgM gene in the spleen of the two-month-old grass carp in the vaccine and APS immunization group increased first and then decreased.The expression of IgM mRNA in the three groups reached the peak at 72 h,and the vaccine and APS immunization groups were 2.8 times of the control group.The expression of 24 h in the head kidney was higher than that in the control group.The immunization group and the APS immunity were 4.2 times and 4.5 times of the control group,respectively.The level of C3 mRNA in the vaccine and APS immunized group was higher than that in the control group at different time points in the spleen and the head kidney,but there was no significant difference.There was no significant difference in LSZ mRNA between the spleen and the head kidney and the control group.The spleen and head kidney of the APS immunized group had significant difference with the control group at 0-12 h.After GCRV challenge,the mortality of the vaccine and APS was lower than that of the control group.Studies showed that maternal immunity can enhance the transmission of immune factors in grass carp between generations,and play a certain immune protection on the offspring in response to GCRV.