Identification of common immunodominant antigens of Eimeria tenella, Eimeria acervulina and Eimeria maxima by immunoproteomic analysis

Abstract

Clinical chicken coccidiosis is mostly caused by simultaneous infection of several Eimeria species, and host immunity against Eimeria is species-specific. It is urgent to identify common immunodominant antigen of Eimeria for developing multivalent anticoccidial vaccines. In this study, sporozoite proteins of Eimeria tenella, Eimeria acervulina and Eimeria maxima were analyzed by two-dimensional electrophoresis (2DE). Western bot analysis was performed on the yielded 2DE gel using antisera of E. tenella E. acervulina and E. maxima respectively. Next, the detected immunodominant spots were identified by comparing the data from MALDI-TOF-MS/MS with available databases. Finally, Eimeria common antigens were identified by comparing amino acid sequence between the three Eimeria species. The results showed that analysis by 2DE of sporozoite proteins detected 629, 626 and 632 protein spots from E. tenella, E. acervulina and E. maxima respectively. Western bot analysis revealed 50 (E. tenella), 64 (E. acervulina) and 57 (E. maxima) immunodominant spots from the sporozoite 2DE gels of the three Eimeria species. The immunodominant spots were identified as 33, 27 and 25 immunodominant antigens of E. tenella, E. acervulina and E. maxima respectively. Fifty-four immunodominant proteins were identified as 18 ortholog proteins among the three Eimeria species. Finally, 5 of the 18 ortholog proteins were identified as common immunodominant antigens including elongation factor 2 (EF-2), 14-3-3 protein, ubiquitin-conjugating enzyme domain-containing protein (UCE) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH). In conclusion, our results not only provide Eimeria sporozoite immunodominant antigen map and additional immunodominant antigens, but also common immunodominant antigens for developing multivalent anticoccidial vaccines.

Immunoproteomic and mass spectrometric analysis of Eimeria acervulina antigens recognized by antisera from chickens infected with E. acervulina, E. tenella or E. necatrix

“…The present study represents the first to show E. acervulina antigens recognized by sera specific to E. acervulina as well as those specific to E. tenella or E. necatrix. Interestingly, most of the E. acervulina proteins with shared immunogenicity identified in the present study were not found in a similar study where anti-E. acervulina sera were used to detect E. acervulina antigens [30]. One apparent difference between the studies is that we used antisera with much higher titers (1:1280), which could in part account for why the proteins identified in our study are not shown in the study by Liu et al [30].…”

“…Interestingly, most of the E. acervulina proteins with shared immunogenicity identified in the present study were not found in a similar study where anti-E. acervulina sera were used to detect E. acervulina antigens [30]. One apparent difference between the studies is that we used antisera with much higher titers (1:1280), which could in part account for why the proteins identified in our study are not shown in the study by Liu et al [30]. Future research is warranted to compare Eimeria antigens identified under similar experimental conditions.…”

“…As previously reported, protein spots were removed from the SDS-PAGE gel and subjected to trypsin digestion and desalination [30]. MS analysis of protein spots was performed by the Experimental Center of Nanjing Medical University (Nanjing, China).…”

Genome-wide analysis of differentially expressed profiles of mRNAs, lncRNAs and circRNAs in chickens during Eimeria necatrix infection

“…Coccidiosis, a deadly disease of chickens worldwide, seriously hampers birds' productivity and welfare [85]. However, most previous studies mainly focused on revealing the functions of protein molecules or protein-coding genes during Eimeria infection [86][87][88][89]. In the present study, we first identified 818 lncRNAs and 4153 circRNAs in mid-segments of chicken small intestines at 108 h pi of E. necatrix, and found that 95 lncRNAs and 13 circRNAs were significantly differentially regulated due to infection.…”

Protective immunity induced by Eimeria common antigen 14–3-3 against Eimeria tenella, Eimeria acervulina and Eimeria maxima

“…However, the reported common antigens were not well identified by sequencing and their protective efficacies have not been evaluated. In the earlier study of our lab, Ea14–3-3 antigen was identified as one of the common immunodominant antigens from E. tenella , E. acervulina and E. maxima [ 14 ]. It has been documented that 14–3-3 proteins are involved in many patho-physiological and cellular immune processes by triggering or interfering with the activity of specific protein associates [ 15 ].…”