Jassim A, Gillott D J, al-Zuhdi Y
Department of Immunology, London Hospital Medical College, UK.
Hum Reprod. 1991 Sep;6(8):1135-42. doi: 10.1093/oxfordjournals.humrep.a137499.
The phosphorylation of the human sperm tail fibrous sheath as a maturational step during its development is reported for the first time. This was demonstrated using GDA-J/F3 and RT97 monoclonal antibodies (MoAb) which recognize the fibrous sheath. In indirect immunofluorescence microscopy of frozen sections of human adult testes, the two antibodies reacted with the assembled fibrous sheath only, but the numbers of sperm tails stained with RT97 were consistently lower than those treated with GDA-J/F3. Furthermore, by using double indirect immunofluorescence, although the majority of spermatozoa were doubly stained with the two MoAbs, some GDA-J/F3-positive sperm tails were negative with RT97. In epididymal and ejaculated spermatozoa, the two antibodies stained all the tails. This indicated that the ontogenic appearance of the GDA-J/F3 epitope precedes that of RT97. In Western blotting and/or indirect immunofluorescence of spermatozoa, treatment of samples with alkaline phosphatase abolished the reactivity of RT97 while that of GDA-J/F3 MoAb was not affected. This finding indicated that the RT97 but not the GDA-J/F3 epitope was phosphorylated. Together, these results therefore reveal that during tail morphogenesis, the fibrous sheath undergoes phosphorylation as part of its structural maturation. Screening of sperm cell precursors recovered from oligozoospermic donors showed reaction of some abnormal germ cells with GDA-J/F3 MoAb but not with RT97, suggesting the possible failure of phosphorylation of the fibrous sheath protein in these cells. The significance of these findings is discussed together with the biological importance of phosphorylation to the fibrous sheath.
首次报道了人类精子尾部纤维鞘磷酸化是其发育过程中的一个成熟步骤。这是通过使用识别纤维鞘的GDA-J/F3和RT97单克隆抗体（MoAb）来证明的。在成人睾丸冰冻切片的间接免疫荧光显微镜检查中，这两种抗体仅与组装好的纤维鞘发生反应，但用RT97染色的精子尾部数量始终低于用GDA-J/F3处理的数量。此外，通过双重间接免疫荧光法，虽然大多数精子被这两种单克隆抗体双重染色，但一些GDA-J/F3阳性的精子尾部用RT97检测呈阴性。在附睾和射出的精子中，这两种抗体对所有尾部都有染色。这表明GDA-J/F3表位的个体发生出现先于RT97。在精子的蛋白质印迹和/或间接免疫荧光检测中，用碱性磷酸酶处理样品会消除RT97的反应性，而GDA-J/F3单克隆抗体的反应性不受影响。这一发现表明RT97表位而非GDA-J/F3表位发生了磷酸化。因此，这些结果共同揭示了在尾部形态发生过程中，纤维鞘作为其结构成熟的一部分会发生磷酸化。对从少精子症供体中回收的精子细胞前体进行筛选显示，一些异常生殖细胞与GDA-J/F3单克隆抗体发生反应，但与RT97不发生反应，这表明这些细胞中纤维鞘蛋白可能未发生磷酸化。本文讨论了这些发现的意义以及纤维鞘磷酸化的生物学重要性。
