Evaluation of the immune protective effects of rEmMIC2 and rEmMIC3 from Eimeria magna in rabbits

Abstract

Eimeria magna is a common pathogen in rabbits, which results in lethargy, weight loss, diarrhea, and even death in severe cases after infection. The current method for preventing rabbit coccidiosis is to add anticoccidial drugs to the diet. However, there are many concerns about drug resistance and drug residues. In our study, the rEmMIC2 and rEmMIC3 proteins were cloned and expressed to evaluate potential as recombinant subunit vaccine candidate antigens. The protective effects of rEmMIC2 and rEmMIC3 were evaluated by the relative weight gain ratio, oocyst decrease rate, anticoccidial index, feed conversion ratio, pathological alterations, clinical symptoms, specific IgG antibody, and cytokine levels in rabbits. The molecular weights of rEmMIC2 and rEmMIC3 were 18.69 kDa and 17.47 kDa, respectively. After the coccidia challenge, the control groups showed anorexia and soft poop, whereas the experimental group showed few anorexia symptoms. Significantly different from the control group, the relative weight gain ratios of the immunized rEmMIC2 and rEmMIC3 groups were 78.37% and 75.29%, respectively, and the oocyst reduction was 77.95% and 76.09%, respectively, and the anticoccidial index was 171.12 and 169.29, respectively. IgG antibody, IFN-γ, IL-4, IL-10, and IL-17 levels were significantly increased in the experimental group. The results showed that rEmMIC2 and rEmMIC3 have potential as vaccine candidate antigens.

Assessment of the Immunoprotective Efficacy of Recombinant 14-3-3 Protein and Dense Granule Protein 10 (GRA10) as Candidate Antigens for Rabbit Vaccines against Eimeria intestinalis

“…The immunization of r with recombinant E. stiedae surface antigen rEs-SAG13 [27], apical membrane antige AMA1 [28], and immune-mapped protein rEs-IMP1 [28] resulted in 82.8%, 74.6% 80.0% oocyst reductions, respectively, and significantly higher relative body w growth rates compared to the control group, reaching 88.77%, 78.1%, and 94.4%, r tively. The recombinant E. magna surface antigens rEm-SAG10 and rEm-SAG11 [2 microneme proteins rEm-MIC2 and rEm-MIC3 [30], the gametophyte antigen rEm-G [31], and the rhoptry protein rEm-ROP17 [31] provided good immune protection af immunization of the rabbits. There was only one study of a recombinant subunit v against E. intestinalis, indicating that rEi-AMA1 and rEi-IMP1 provided moderate im protection in rabbits, with ACI values of 152.09 and 147.17, respectively [17].…”

Krameria lappacea root extract’s anticoccidial properties and coordinated control of CD4 T cells for IL-10 production and antioxidant monitoring

“…Cell-mediated immunity driven by T lymphocytes, macrophages, and other effector cells plays a major role in host protection against coccidiosis ( 1 ). Upon activation by invading the coccidian Eimeria parasite, CD4 T cells can differentiate into various types of helper T cells that are responsible for regulating host immune responses by secreting cytokines and proinflammatory molecules ( 2 ). Eimeria species are highly species and site-specific within the host.…”