This Article Full Text Full Text (PDF) Other Versions of this Article: IAI.01171-06v1 75/4/2004    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Shi, J. Articles by Xu, C. Search for Related Content PubMed PubMed Citation Articles by Shi, J. Articles by Xu, C.

Screening of an Antigen Target for Immunocontraceptives from Cross-Reactive Antigens between Human Sperm and Ureaplasma urealyticum

Jianli Shi,¹ Zhengmin Yang,² Min Wang,¹ Guoyan Cheng,¹ Ding Li,¹ Yifei Wang,¹ Yuancong Zhou,² Xiaolong Liu,^2*, and Chen Xu^1*,

Department of Histology and Embryology, Shanghai Jiao Tong University School of Medicine, Shanghai, China,¹ Laboratory of Molecular Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China²

Received 25 July 2006/ Returned for modification 4 September 2006/ Accepted 22 January 2007

Epidemiologic studies indicated that some infertile men who were infected with Ureaplasma urealyticum displayed positive antisperm antibodies in their serum and/or semen. The purpose of this study was to investigate the possible mechanism of antisperm antibodies production after infection with U. urealyticum and to analyze the relationship between U. urealyticum and infertility. The existence of cross-reactive antigens (61, 50, and 25 kDa) between U. urealyticum and human sperm membrane proteins was confirmed. Among the cross-reactive antigens, the urease complex component UreG of U. urealyticum was determined. By searching the Swiss-Prot protein database, a pentapeptide identity (IERLT) between UreG and human nuclear autoantigenic sperm protein (NASP) was found. Furthermore, using Western blot analysis and enzyme-linked immunosorbent assay, the cross-reaction between the NASP and UreG was verified. Both anti-rUreG antibody and the antiserum against the synthetic peptide NASP393-408 containing the pentapeptide inhibited mouse sperm egg binding and fusion. After immunization by rUreG or the synthetic peptide, 81.2 and 75% female mice became sterile, respectively. The effect on fertility in mice immunized with the synthetic peptide was reversible. These findings proved for the first time that it was feasible to screen antigens for immunocontraceptives from cross-reactive antigens between sperm and microorganisms which induce infertility.

Published ahead of print on 5 February 2007.

Editor: R. P. Morrison

X.L. and C.X. contributed equally to this study.