Cryptosporidium parvum sporozoite pellicle antigen recognized by a neutralizing monoclonal antibody is a beta-mannosylated glycolipid.
Cryptosporidium parvum sporozoite pellicle antigen recognized by a neutralizing monoclonal antibody is a beta-mannosylated glycolipid.
复制标题
中和单克隆抗体识别的小隐孢子虫子孢子表膜抗原是 β-甘露糖化糖脂。
DOI：
10.1128/iai.67.3.1317-1322.1999
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发表时间：
1999
影响因子：
3.1
通讯作者：
O'Connor,RM
中科院分区：
文献类型：
--
作者：
Riggs,MW;McNeil,MR;Perryman,LE;Stone,AL;Scherman,MS;O'Connor,RM
The protozoan parasiteCryptosporidium parvumis an important cause of diarrhea in humans, calves, and other mammals worldwide. No approved vaccines or parasite-specific drugs are currently available for the control of cryptosporidiosis. To effectively immunize againstC. parvum, identification and characterization of protective antigens are required. We previously identified CPS-500, a conserved, neutralization-sensitive antigen ofC. parvumsporozoites and merozoites defined by monoclonal antibody 18.44. In the present study, the biochemical characteristics and subcellular location of CPS-500 were determined. CPS-500 was chloroform extractable and eluted with acetone and methanol in silicic acid chromatography, consistent with being a polar glycolipid. Following chloroform extraction and silicic acid chromatography, CPS-500 was isolated by high-pressure liquid chromatography for glycosyl analysis, which indicated the presence of mannose and inositol. To identify which component of CPS-500 comprised the neutralization-sensitive epitope recognized by 18.44, the ability of the monoclonal antibody to bind CPS-500 treated with proteases, or with α- or β-glycosidases, was determined. Monoclonal antibody 18.44 did not bind antigen treated with β-d-mannosidase but did bind antigen treated with α-d-mannosidase, other α- or β-glycosidases, or a panel of proteases. These data indicated that the target epitope was dependent on terminal β-d-mannopyranosyl residues. By immunoelectron microscopy, 18.44 binding was localized to the pellicle and an intracytoplasmic tubulovesicular network in sporozoites. Monoclonal antibody 18.44 also bound to antigen deposited and released onto substrate over the course travelled by gliding sporozoites and merozoites. Surface localization, adhesion and release during locomotion, and neutralization sensitivity suggest that CPS-500 may be involved in motility and invasion processes of the infective zoite stages.
