Xuenan Xuan
Obihiro University of Agriculture and Veterinary Medicine, Japan
Title: Development of recombinant vaccines against Babesia microti infection by using apical membrane protein 1
Biography
Biography: Xuenan Xuan
Abstract
In this study, the protective effect of recombinant Babesia microti apical membrane protein 1 (rBmAMA1) and rhoptry neck protein 2 (rBmRON2) against B. microti infection was evaluated in a hamster model. The genes encoding the predicted domains I and II of BmAMA1 and the gene encoding the predicted transmembrane regions 2 and 3 of BmRON2 were expressed as his fusion recombinant proteins in Escherichia coli. Three groups with five hamsters in each group were immunized with rBmAMA1, rBmRON2 and rBmAMA1þ rBmRON2, and then challenged with B. microti. The result showed that only the group immunized with rBmAMA1þ rBmRON2 exhibited protection against B. microti challenge infection, characterized by significant decreased of parasitemia and higher hematocrit values from day’s six-10 post challenge infection. However, there was no significant difference in the groups immunized with rBmAMA1 or rBmRON2 alone. The absence of a significant difference in the total amount of antibodies against rBmAMA1 and rBmRON2 between the groups immunized with single and combined proteins. This result indicates that the protection cannot be solely attributed to the quantity of antibodies produced, but also to their ability to target important epitopes from both antigens. These results suggest that combined immunization with rBmAMA1 and rBmRON2 is a promising strategy against B. microti infection.