title: Antibody responses to individual proteins of SARS coronavirus and their neutralization activities.
abstract: A novel coronavirus, the severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV), was identified as the causative agent of SARS. The profile of specific antibodies to individual proteins of the virus is critical to the development of vaccine and diagnostic tools. In this study, 13 recombinant proteins associated with four structural proteins (S, E, M and N) and five putative uncharacterized proteins (3a, 3b, 6, 7a and 9b) of the SARS-CoV were prepared and used for screening and monitoring their specific IgG antibodies in SARS patient sera by protein microarray. Antibodies to proteins S, 3a, N and 9b were detected in the sera from convalescent-phase SARS patients, whereas those to proteins E, M, 3b, 6 and 7a were undetected. In the detectable specific antibodies, anti-S and anti-N were dominant and could persist in the sera of SARS patients until week 30. Among the rabbit antisera to recombinant proteins S3, N, 3a and 9b, only anti-S3 serum showed significant neutralizing activity to the SARS-CoV infection in Vero E6 cells. The results suggest (1) that anti-S and anti-N antibodies are diagnostic markers and in particular that S3 is immunogenic and therefore is a good candidate as a subunit vaccine antigen; and (2) that, from a virus structure viewpoint, the presence in some human sera of antibodies reacting with two recombinant polypeptides, 3a and 9b, supports the hypothesis that they are synthesized during the virus cycle.
authors.affiliation: Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences, No. 20, Dongdajie, Fengtai District, Beijing 100071, China.
authors.forename: Maofeng
authors.initials: M
authors.lastname: Qiu
authors.forename: Yuling
authors.initials: Y
authors.lastname: Shi
authors.forename: Zhaobiao
authors.initials: Z
authors.lastname: Guo
authors.forename: Zeliang
authors.initials: Z
authors.lastname: Chen
authors.forename: Rongqiao
authors.initials: R
authors.lastname: He
authors.forename: Runsheng
authors.initials: R
authors.lastname: Chen
authors.forename: Dongsheng
authors.initials: D
authors.lastname: Zhou
authors.forename: Erhei
authors.initials: E
authors.lastname: Dai
authors.forename: Xiaoyi
authors.initials: X
authors.lastname: Wang
authors.forename: Bingyin
authors.initials: B
authors.lastname: Si
authors.forename: Yajun
authors.initials: Y
authors.lastname: Song
authors.forename: Jingxiang
authors.initials: J
authors.lastname: Li
authors.forename: Ling
authors.initials: L
authors.lastname: Yang
authors.forename: Jin
authors.initials: J
authors.lastname: Wang
authors.forename: Hongxia
authors.initials: H
authors.lastname: Wang
authors.forename: Xin
authors.initials: X
authors.lastname: Pang
authors.forename: Junhui
authors.initials: J
authors.lastname: Zhai
authors.forename: Zongmin
authors.initials: Z
authors.lastname: Du
authors.forename: Ying
authors.initials: Y
authors.lastname: Liu
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
authors.forename: Linhai
authors.initials: L
authors.lastname: Li
authors.forename: Jian
authors.initials: J
authors.lastname: Wang
authors.forename: Bing
authors.initials: B
authors.lastname: Sun
authors.forename: Ruifu
authors.initials: R
authors.lastname: Yang
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000096:biosynthesis / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology; D009500:Neutralization Tests; D011817:Rabbits; D045473:Severe acute respiratory syndrome-related coronavirus / Q000276:immunology*; D014764:Viral Proteins / Q000276:immunology*
chemical_list: D000914:Antibodies, Viral; D007074:Immunoglobulin G; D014764:Viral Proteins