Influence of enterococci on human sperm membrane in vitro

Qiang Hua^1*, Jiang Mingsen¹, Lin Jianyin², He Weimin<sup>3

1</sup> Department of Etiology, School of Medicine, Wuhan University, Wuhan 430071, China
² Department of Etiology, Fujian Medical University, Fuzhou 350004, China
³Department of Anatomy, Histology and Embryology, Fujian Medical University, Fuzhou 350004, China

DOI: 10.1111/j.1745-7262.2006.00219.x

Abstract
Aim: To study the influence of enterococci on human sperm membrane in vitro. Methods: Ejaculated human sperm were artificially infected with β-hemolytic or non-β-hemolytic enterococci at bacteria: sperm ratio of 50:1 at 37 °C. Sperm membrane integrity was examined after incubation for 1, 3 and 5 h by hypoosmotic swelling (HOS) test and electron microscopy. Results: Sperm infected with β-hemolytic enterococci had lower HOS scores compared with non-β-hemolytic strains or uninfected control (P < 0.01). The HOS test scores of sperm infected with β-hemolytic enterococci increased in the presence of phosphatidylcholine, an inhibitor of hemolysin. It was shown by electron microscopy that β-hemolytic enterococci caused significant rupture of human sperm membrane. Conclusion: β-hemolytic enterococci caused human sperm membrane injury, and might be mediated by the hemolysin of enterococci.

Key words: enterococci; sperm; hypoosmotic swelling test; ultrastructure

Correspondence to: Prof. Qiang Hua, Department of Etiology, Fujian Medical University, 88 Jiaotong Road, Fuzhou, Fujian 350004, China.
Tel: +86-591-8356-9309
E-mail: qianghua66@sina.com
^*Present address: Department of Etiology, Fujian Medical University, Fuzhou, Fujian 350004, China
Received 2006-05-17 ?Accepted 2006-06-05