Expression of Babesia equi EMA-1 and EMA-2 during merozoite developmental stages in erythrocyte and their interaction with erythrocytic membrane skeleton.
In the present study, we investigated the cellular localizations and expression patterns of equi merozoite antigens (EMA) -1 and -2 of Babesia equi during its asexual erythrocytic-developmental cycle using anti-EMA-1t or -2t mono-specific mouse serum. Indirect fluorescent antibody tests demonstrated that EMA-1 and EMA-2 were not expressed in all the erythrocytic-developmental stages of the merozoites and that these two antigens were co-expressed during the early developmental stages. Additionally, it was shown that EMA-1 and EMA-2 were mutually expressed on the surface of extra-erythrocytic merozoites and also that the intra-erythrocytic merozoites shed only EMA-2 antigen in the infected erythrocytic cytoplasm or inside the membrane surface. The specific binding of EMA-2 to a Triton X-100-insoluble horse erythrocyte membrane fraction was also demonstrated. These findings facilitate our understanding of the biological roles of merozoite surface proteins of B. equi and our investigation for new drug targets.
Kumar
Sanjay
S
National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido 080-8555, Japan.
Yokoyama
Naoaki
N
Kim
Jung-Yeon
JY
Huang
Xiaohong
X
Inoue
Noboru
N
Xuan
Xuenan
X
Igarashi
Ikuo
I
Sugimoto
Chihiro
C
D000818:Animals; D000913:Antibodies, Protozoan / Q000378:metabolism; D000953:Antigens, Protozoan / Q000096:biosynthesis* / Q000276:immunology / Q000378:metabolism; D001403:Babesia / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D004910:Erythrocyte Membrane / Q000378:metabolism*; D004912:Erythrocytes / Q000469:parasitology*; D019084:Fluorescent Antibody Technique, Indirect; D015870:Gene Expression; D017125:Genes, Protozoan / Q000235:genetics / Q000502:physiology; D008565:Membrane Proteins / Q000096:biosynthesis* / Q000276:immunology / Q000378:metabolism; D018613:Microscopy, Confocal; D015800:Protozoan Proteins / Q000096:biosynthesis* / Q000276:immunology / Q000378:metabolism
D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; C085964:EMA-1 protein, Babesia equi; C111468:EMA-2 protein, Babesia equi; D008565:Membrane Proteins; D015800:Protozoan Proteins