A sialoglycoprotein, gp20, of the human capacitated sperm surface is a homologue of the leukocyte CD52 antigen: analysis of the effect of anti-CD52 monoclonal antibody (CAMPATH-1) on capacitated spermatozoa
A sialoglycoprotein, gp20, of the human capacitated sperm surface is a homologue of the leukocyte CD52 antigen: analysis of the effect of anti-CD52 monoclonal antibody (CAMPATH-1) on capacitated spermatozoa
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DOI：
10.1093/molehr/5.1.46
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发表时间：
1999-01-01
影响因子：
4
通讯作者：
Rosati, F
中科院分区：
文献类型：
--
作者：
Focarelli, R;Francavilla, S;Rosati, F
在这项研究中，我们对 gp20 进行了高末端序列分析，gp20 是人类精子表面上的一种 20 kDa 唾液酸糖蛋白，之前通过精子表面唾液酸残基的放射性标记来鉴定。我们发现它与几乎所有人类白细胞上表达的抗原 CD52 的 N 末端具有 100% 的一致性。我们还表明，与 CD52 一样，gp20 表现为糖基磷脂酰肌醇 (GPI) 锚定蛋白，并且抗 gp20 抗血清与与 CD52 分子量相同的白细胞上的抗原发生反应。使用针对CD52的单克隆抗体CAMPATH-1，在获能精子的荧光染色、蛋白质印迹分析和无带仓鼠卵穿透试验中，我们发现该抗体的效果与我们的抗gp20的效果不同。蛋白质印迹分析显示抗 gp20 具有明确的 20 kDa 带，而 CAMPATH-1 则检测到 14-20 kDa 带。在获能精子的免疫荧光分析中，抗 gp20 对精子头部的赤道区域进行染色，而 CAMPATH-1 对尾部进行染色。在无透明带仓鼠卵渗透试验中，CAMPATH-1 具有剂量依赖性抑制作用，与之前使用抗 gp20 检测到的效果类似。然而，用 CAMPATH-1 检测到活动精子的凝集，而抗 gp20 则不存在这种情况。这表明两种抗体识别的表位不同。
In this study we performed hi-terminal sequence analysis of gp20, a 20 kDa sialoglycoprotein on the human sperm surface previously identified by radiolabelling of the sialic acid residues of sperm surface. We found 100% identity with the N-terminus of CD52, an antigen expressed on almost all human leukocytes. We also show that, like CD52, gp20 behaves as a glycosylphosphatidylinositol (GPI)-anchored protein and that anti-gp20 antiserum reacts with an antigen on leukocytes of the same molecular weight as CD52. Using CAMPATH-1, the monoclonal antibody against CD52, in fluorescent staining of capacitated spermatozoa, Western blot analysis and the zona-free hamster egg penetration test, we found that the effect of this antibody was different from that of our anti-gp20. Western blot analysis revealed a well-defined 20 kDa band with anti-gp20, whereas a 14-20 kDa band was detected with CAMPATH-1. Anti-gp20 stained the equatorial region of the sperm head, whereas CAMPATH-1 stained the tail in immunofluorescence analysis of capacitated spermatozoa. A dose-dependent inhibitory effect was seen with CAMPATH-1, similar to that previously detected with anti-gp20, in a zona-free hamster egg penetration test. However, with CAMPATH-1 agglutination of motile spermatozoa was detected, and this was not present with anti-gp20. This suggests that the epitopes recognized by the two antibodies are different.