Flickinger C J, Rao J, Bush L A, Sherman N E, Oko R J, Jayes F C, Herr J C
Department of Cell Biology and the Center for Recombinant Gamete Contraceptive Vaccinogens, University of Virginia, Charlottesville, Virginia 22908, USA.
Biol Reprod. 2001 May;64(5):1451-9. doi: 10.1095/biolreprod64.5.1451.
Obstruction of the male reproductive tract commonly results in generation of antisperm autoantibodies. However, only a few of the sperm autoantigens recognized by these antibodies have been characterized. To identify postobstruction rat sperm autoantigens, sperm proteins were separated by two-dimensional(2-D) gel electrophoresis. Spots corresponding to proteins that were stained by at least 50% of postvasectomy rat sera on 2-D Western blots were removed from polyacrylamide gels and microsequenced by tandem mass spectrometry. From a total of 21 spots, 12 contained peptides that matched solely to either of two outer dense fiber proteins, odf1 or odf2. Six additional spots contained peptides comprising odf1 or odf2 and were accompanied by peptides representing other proteins. Only three spots lacked outer dense fiber peptides but did contain sequences of other known proteins. The results indicate that the outer dense fiber proteins odf1 and odf2 are dominant postobstruction autoantigens because they were detected in the majority of the immunoreactive protein spots examined. Possible explanations for this observation include the abundance of outer dense fiber proteins in spermatozoa, slow solubility, which may provide a sustained supply of antigen, and testis-specific expression during spermiogenesis.
男性生殖道梗阻通常会导致抗精子自身抗体的产生。然而，这些抗体所识别的精子自身抗原中，只有少数已被鉴定。为了鉴定梗阻后大鼠精子自身抗原，通过二维（2-D）凝胶电泳分离精子蛋白。在二维蛋白质印迹上，将至少50%的输精管结扎术后大鼠血清染色的蛋白质对应的斑点从聚丙烯酰胺凝胶中切下，并通过串联质谱进行微测序。在总共21个斑点中，12个含有仅与两种外致密纤维蛋白odf1或odf2之一匹配的肽段。另外6个斑点含有包含odf1或odf2的肽段，并伴有代表其他蛋白质的肽段。只有3个斑点缺乏外致密纤维肽段，但确实含有其他已知蛋白质的序列。结果表明，外致密纤维蛋白odf1和odf2是梗阻后主要的自身抗原，因为在大多数检测的免疫反应性蛋白斑点中都检测到了它们。对此观察结果的可能解释包括精子中外致密纤维蛋白的丰度、缓慢的溶解性（这可能提供持续的抗原供应）以及精子发生过程中的睾丸特异性表达。
