Boockfor F R, Schwarz L K
Department of Anatomy and Cell Biology, Medical University of South Carolina, Charleston 29425-2204.
Endocrinology. 1991 Jul;129(1):256-62. doi: 10.1210/endo-129-1-256.
Recent studies demonstrate that several cytokines are potent modulators of steroid release from the testis. In an attempt to determine whether these agents may influence other types of secreted substances, we used plaque assays to measure the effect of interleukin-6 (IL-6), interleukin-2 (IL-2), and tumor necrosis factor alpha on transferrin (TF) release from Sertoli cells in culture. Because Sertoli cells from different parts of the tubule respond differently to modulatory factors, we used cultures obtained by microdissection from stages III-V, VII, IX-XI, and XIII of the cycle of the seminiferous epithelium. Our results revealed that each agent increased the rate of TF plaque formation from cultures of IX-XI, and XIII staged segments but not from those staged III-V and VII. Moreover, IL-6, but not the other cytokines, modified the response of Sertoli cells to another regulator, FSH. This was evidenced by our findings that pretreatment with IL-6 for 1 h resulted in FSH-induced increases in the rate of plaque formation for cells from IX-XI segments, in addition to those segments which are normally responsive without pretreatment (III-V and VII segments). Further experiments revealed that IL-6 also had a chronic influence on the proportion of TF secretors present in certain staged cultures. Treatment for 24 h with IL-6 markedly reduced the percentage of TF secretors in cultures from stage XIII segments and resulted in a slight increase in TF cells for stage VII cultures. However, no chronic influences in TF secretors were detected with either IL-2 or tumor necrosis factor alpha treatment. Our results demonstrate very clearly that certain cytokines acting in a stage specific manner have acute and/or chronic influences on the release of TF from Sertoli cells. These findings, when viewed in light of reports of the presence of these factors in the testis, suggest strongly that cytokines or cytokine-like substances, by modulating the release of Sertoli cell substances, may play an important role in testis function.
近期研究表明，几种细胞因子是睾丸类固醇释放的强效调节剂。为了确定这些因子是否会影响其他类型的分泌物质，我们采用噬斑测定法来检测白细胞介素-6（IL-6）、白细胞介素-2（IL-2）和肿瘤坏死因子α对培养的支持细胞转铁蛋白（TF）释放的影响。由于来自小管不同部位的支持细胞对调节因子的反应不同，我们使用了从生精上皮周期的III-V期、VII期、IX-XI期和XIII期通过显微切割获得的培养物。我们的结果显示，每种因子均增加了IX-XI期和XIII期片段培养物中TF噬斑形成的速率，但III-V期和VII期片段培养物中未增加。此外，IL-6而非其他细胞因子改变了支持细胞对另一种调节因子促卵泡激素（FSH）的反应。我们的研究结果证明了这一点，即先用IL-6预处理1小时，除了那些未经预处理就有反应的片段（III-V期和VII期片段）外，还导致IX-XI期片段细胞中FSH诱导的噬斑形成速率增加。进一步的实验表明，IL-6对某些分期培养物中TF分泌细胞的比例也有慢性影响。用IL-6处理24小时显著降低了XIII期片段培养物中TF分泌细胞的百分比，并导致VII期培养物中TF细胞略有增加。然而，用IL-2或肿瘤坏死因子α处理未检测到对TF分泌细胞的慢性影响。我们的结果非常清楚地表明，某些以阶段特异性方式起作用的细胞因子对支持细胞中TF的释放有急性和/或慢性影响。鉴于睾丸中存在这些因子的报道，这些发现强烈表明，细胞因子或细胞因子样物质通过调节支持细胞物质的释放，可能在睾丸功能中发挥重要作用。
