This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Tian, Y.
Right arrow Articles by Yang, D.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Tian, Y.
Right arrow Articles by Yang, D.

 Previous Article  |  Next Article 

Journal of Clinical Microbiology, September 2007, p. 2971-2978, Vol. 45, No. 9
0095-1137/07/$08.00+0     doi:10.1128/JCM.00508-07
Copyright © 2007, American Society for Microbiology. All Rights Reserved.

The Amino Acid Residues at Positions 120 to 123 Are Crucial for the Antigenicity of Hepatitis B Surface Antigen{triangledown}

Yongjun Tian,1,{dagger} Yang Xu,2,3,{dagger} Zhenhua Zhang,1 Zhongji Meng,1 Li Qin,1 Mengji Lu,2,3* and Dongliang Yang1*

Division of Clinical Immunology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China,1 Institute of Virology, University Hospital of Essen, Essen, Germany,2 Department of Microbiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China3

Received 6 March 2007/ Returned for modification 4 May 2007/ Accepted 25 June 2007

The major hydrophilic region (MHR) of hepatitis B surface antigen (HBsAg) harbors conformational B-cell epitopes and is the major target of neutralizing antibodies to HBsAg (anti-HBs). Mutant HBsAg (mtHBsAg) with amino acid substitutions such as G145R is known to affect the binding of specific anti-HB antibodies and their detection by conventional diagnostic assays. In the present study, we focused on the role of the amino acid positions 120 to 123, which are around MHR 2 according to the spectrum of recently identified, naturally occurring mtHBsAg. Strikingly, the amino acid substitution K122I abolished the reactivity of HBsAg in all immunoassays tested so far. Also, mtHBsAg G145R could be clearly detected with four different enzyme-linked immunosorbent assays that were based on monoclonal anti-HB antibodies (MAbs) with high affinity. Positive immunofluorescence staining of mtHBsAg K122I was achieved only by polyclonal anti-HBs, while all MAbs tested failed. mtHBsAg T123N showed a low reactivity in immunoassays and appeared to be secretion defective. The amino acid substitution P120T reduced the binding of anti-HBs but did not completely prevent the detection of mtHBsAg by anti-HB MAbs. The testing of naturally occurring mtHBsAg confirmed that the presence of amino acid substitutions within the region of 120 to 123 is strongly associated with impaired detection in immunoassays. In conclusion, MHR 2 is essential for HBsAg antigenicity, a fact that has not been recognized before.


* Corresponding author. Mailing address for Mengji Lu: Institut für Virologie, Universitätsklinikum Essen, Hufelandstrasse 55, 45122 Essen, Germany. Phone: 49 201 723 3530. Fax: 49 201 723 5929. E-mail: mengji.lu{at}uni-due.de. Mailing address for Dongliang Yang: Division of Clinical Immunology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Jiefang Avenue 1095, 430030 Wuhan, People's Republic of China. Phone and fax: 0086 27 8366 2894. E-mail: dlyang{at}tjh.tjmu.edu.cn

{triangledown} Published ahead of print on 3 July 2007.

{dagger} These authors contributed equally to this work.


Journal of Clinical Microbiology, September 2007, p. 2971-2978, Vol. 45, No. 9
0095-1137/07/$08.00+0     doi:10.1128/JCM.00508-07
Copyright © 2007, American Society for Microbiology. All Rights Reserved.