Jung Heejun, Roser Janet F, Yoon Minjung
Department of Animal and Biotechnology Science, Kyungpook National University, Sangju, Korea.
Department of Animal Science, University of California Davis, Davis, California, United States of America.
PLoS One. 2014 Oct 1;9(10):e108825. doi: 10.1371/journal.pone.0108825. eCollection 2014.
Spermatogonial stem cells (SSCs) continuously undergo self-renewal and differentiation to sustain spermatogenesis throughout adulthood in males. In stallions, SSCs may be used for the production of progeny from geldings after cryopreservation and therapy for infertile and subfertile stallions. Undifferentiated cell transcription factor 1 (UTF1) is a putative marker for undifferentiated spermatogonia in humans and rats. The main purposes of this study are to determine the following: 1) changes in the expression pattern of UTF1 at various reproductive stages of stallions, 2) subpopulations of spermatogonia that express UTF1. Testicular samples were collected and categorized based on the age of the horses as follows: pre-pubertal (<1 yr), pubertal (1-1.5 yr), post-pubertal (2-3 yr), and adult (4-8 yr). Western blot analysis was utilized to determine the cross-activity of the UTF1 antibody to horse testes tissues. Immunohistochemistry was conducted to investigate the UTF1 expression pattern in germ cells at different reproductive stages. Whole mount staining was applied to determine the subpopulation of UTF1-positive spermatogonia. Immunohistological analysis showed that most germ cells in the pre-pubertal and pubertal stages were immunolabeled with UTF1, whereas only a few germ cells in the basal compartment of the seminiferous tubule cross-sections of post-pubertal and adult tissues were UTF1-positive. No staining was observed in the Sertoli or Leydig cells at any reproductive stages. Whole mount staining showed that A(s), A(pr), and chains of 4, 8, 16 A(al) spermatogonia were immunolabeled with UTF1 in the post-pubertal stallion tubule. Isolated single germ cells were also immunolabeled with UTF1. In conclusion, UTF1 is expressed in undifferentiated spermatogonia, and its antibody can be used as a putative marker for SSCs in stallions.
精原干细胞（SSCs）在雄性成年后的整个生命过程中持续进行自我更新和分化，以维持精子发生。在种马中，精原干细胞可用于在冷冻保存后从去势公马中产生后代，并用于治疗不育和生育力低下的种马。未分化细胞转录因子1（UTF1）是人类和大鼠中未分化精原细胞的一种假定标志物。本研究的主要目的是确定以下内容：1）种马不同生殖阶段UTF1表达模式的变化，2）表达UTF1的精原细胞亚群。收集睾丸样本，并根据马匹年龄进行如下分类：青春期前（<1岁）、青春期（1 - 1.5岁）、青春期后（2 - 3岁）和成年期（4 - 8岁）。利用蛋白质免疫印迹分析来确定UTF1抗体与马睾丸组织的交叉活性。进行免疫组织化学以研究不同生殖阶段生殖细胞中UTF1的表达模式。采用整装染色来确定UTF1阳性精原细胞的亚群。免疫组织学分析表明，青春期前和青春期阶段的大多数生殖细胞都被UTF1免疫标记，而青春期后和成年组织的生精小管横切面基底隔中只有少数生殖细胞是UTF1阳性。在任何生殖阶段的支持细胞或间质细胞中均未观察到染色。整装染色显示，青春期后种马的生精小管中，A(s)、A(pr)以及4、8、16个A(al)精原细胞链被UTF1免疫标记。分离的单个生殖细胞也被UTF1免疫标记。总之，UTF1在未分化的精原细胞中表达，其抗体可作为种马精原干细胞的一种假定标志物。
