巨细胞病毒体外感染对人精子存活率及其运动参数与超微结构的影响

Effect of cytomegalovirus infection on human sperm viability,movement parameters and ultramicrostructure in vitro

目的探讨人巨细胞病毒（HCMV）感染对人精子存活率、精子各运动参数及其超微结构的影响。方法将HCMV与10例经过上游法优化的正常人精子体外共同孵育，于0、1、2、3、4h分别取样，检测精子存活率，并应用计算机辅助精子分析系统（CASA）测定精子直线运动速度（VSL）、曲线运动速度（VCL）、平均路径速度（VAP）、头部侧摆幅度（ALH）和前向运动百分率（a＋b级精子百分率）；同时，电镜观察HCMV感染不同时间人精子超微病理结构的改变。结果与空白、阴性对照组比较，人精子存活率在高浓度HCMV感染后1、3h时明显降低，差异显著（P〈0．05），4h时差异非常显著（P〈0．001）。a＋b级精子百分率仅在高浓度HCMV感染4h时明显降低，差异显著（P〈0．05）。精子VSL在各时间点各组比较差异均无统计学意义（P〉0．05）。精子VCL在高浓度HCMV感染3h时明显下降，差异显著（P〈0．05），4h时显著下降，差异非常显著（P〈0．001）。而中浓度HCMV感染4h时，精子VCL才下降，差异显著（P〈0．05）。精子VAP在高、中浓度HCMV感染2、3、4h时明显降低，差异显著（P〈0．05）。精子ALH在高浓度HCMV感染3、4h时明显下降，差异显著（P〈0．05）。电镜结果显示：人精子超微结构的异常改变在高浓度HCMV感染时常见，4h时严重；主要表现有精子核解聚、空泡增多、顶体破裂、质膜破损、线粒体肿胀及其排列紊乱。结论HCMV体外感染3～4h可造成人精子存活率与运动参数及精子超微结构的异常，且这种改变与HCMV浓度存有一定的量效关系，高浓度HCMV感染的影响结果显著。

Objective To study by in vitro experiment the effects of human cytomegalovirus（HCMV）infection on human spema viability,movement parameters and its ultramicrostructure.Methods HCMV was co- cultured in vitro with normal human sperms optimized by using swim - up technique in 10 persons. The samples were collected at hours 0,1,2,3 and 4,separately. The sperm viability was detected. Computer - aided semen analysis （CASA） was employed to measure the sperm velocity straight linear （VSL）, velocity curve linear （VCL）, velocity average path （VAP）, amplitude of lateral head displacement （ALH）, and progressive motility （percentage of a ＋ b sperms ）. At the same time, the changes of human sperm ultrastructures in different periods of in vitro infection were observed under the electron microscopy. Results The viability of human sperms infected with high concentration HCMV for 1,3 h was significantly dechned in comparison with the corresponding blank and negative control groups （ P 〈 0.05） ,and at h 4,the difference was very significant （ P 〈 0.001 ） .The sperm progressive motility was significantly reduced at h 4 after high concentration HCMV infection （ P 〈 0.05）.At different time points,there was no significant difference in VSL between the two groups （ P 〉 0.05）.At h 3 after high concentration HCMV infection, VCL was significantly decreased （ P 〈 0.05） ,and at 4 h,the difference was very significant （ P 〈 0.001）.At h 4 after moderate concentration HCMV infection,sperm VCL was also decreased （ P 〈 0.05）. The VAP was significantly reduced at hours 2,3 and 4 after high - moderate concentration HCMV infection （ P 〈 0.05 ）. At hours 3 and 4 after high concentration HCMV infection,ALH was significantly reduced （ P 〈 0.05）.Microscopy revealed that no significant changes in the sperm ultrastructure at hours 2 and 4 between the blank and negative control groups. The abnormal changes in the sperm ultrastructure in the high concentration HCMV group were commonly seen,severer at hour 4,and the main lesions included sperm nuclear depolymerization, increased vacuoles, acrosome rupture, damage to cytoplasmic membrane, swelling and irregular arrangement of mitochondria. Conclusions In vitro HCMV infection for 3 - 4 h induces the abnormality of sperm viability, some movement parameters, and sperm ultrastructures, and the change has some dose - effect relationship with the concentration of HCMV. High HCMV infection significantly affects the sperm function and ultrastructure.