LeRoith Tanya, Berens Shawn J, Brayton Kelly A, Hines Stephen A, Brown Wendy C, Norimine Junzo, McElwain Terry F
Program in Vector-Borne Diseases, Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington 99164-7040, USA.
Infect Immun. 2006 Jun;74(6):3663-7. doi: 10.1128/IAI.00032-06.
A hypervariable region (HVR) previously identified in the carboxy-terminal one-third of the Babesia bovis variable merozoite surface antigen family was more extensively analyzed in merozoite surface antigen 1 (MSA-1) from 16 strains and isolates. The MSA-1 HVR is proline rich and contains three semiconserved motifs nearly identical to those described for the related family member MSA-2. Two MSA-1-specific monoclonal antibodies previously shown to be reactive with the merozoite surface bound to a recombinant construct encoding the HVR, indicating that the HVR is surface exposed and accessible to antibody binding. Importantly, these surface-reactive, HVR-specific monoclonal antibodies were capable of inhibiting merozoite infectivity of the host erythrocyte in vivo. The results indicate that the MSA-1 HVR is involved in erythrocyte invasion and suggest that selection of MSA-1 variants may be driven by invasion-blocking antibodies.
先前在牛巴贝斯虫可变裂殖子表面抗原家族羧基末端三分之一区域鉴定出的一个高变区（HVR），在来自16个菌株和分离株的裂殖子表面抗原1（MSA-1）中得到了更深入的分析。MSA-1高变区富含脯氨酸，包含三个半保守基序，与相关家族成员MSA-2中描述的基序几乎相同。两种先前显示与裂殖子表面反应的MSA-1特异性单克隆抗体与编码该高变区的重组构建体结合，表明该高变区暴露于表面且可被抗体结合。重要的是，这些表面反应性、高变区特异性单克隆抗体能够在体内抑制裂殖子对宿主红细胞的感染性。结果表明，MSA-1高变区参与红细胞入侵，并提示MSA-1变体的选择可能由阻断入侵的抗体驱动。
