Rapid Communication
Copyright ©2006 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. Jul 7, 2006; 12(25): 4044-4048
Published online Jul 7, 2006. doi: 10.3748/wjg.v12.i25.4044
Detection of H pylori antibody profile in serum by protein array
Feng-Chan Han, Xu-Jun Li, Hong Jiang, Li-Peng Qin, Ding Li, Yan-Hai Guo, Zhi-Guang Liu, Li Zhang, Xiao-Jun Yan
Feng-Chan Han, Xu-Jun Li, Hong Jiang, Li-Peng Qin, Ding Li, Yan-Hai Guo, Zhi-Guang Liu, Xiao-Jun Yan, Institute of Genetic Diagnosis, State Key Laboratory of Cancer Biology, The Fourth Military Medical University, Xi’an 710032, Shaanxi Province, China
Li Zhang, Department of Gastroenterology,Xi’an Central Hospital, Xi’an, 710032, Shaanxi Province, China
Author contributions: All authors contributed equally to the work.
Supported by National 863 Research Project of China, No. 2002AA232031
Correspondence to: Dr. Feng-Chan Han, Institute of Genetic Diagnosis, The Fourth Military Medical University, 17 West Changle Road, Xi’an 710032, Shaanxi Province, China. fengchan@fmmu.edu.cn
Telephone: +86-29-83216587 Fax: +86-29-83285729
Received: October 21, 2005
Revised: December 15, 2005
Accepted: December 22, 2005
Published online: July 7, 2006
Abstract

AIM: To detect multiple H pylori antibodies in serum samples of individuals who carryH pylori by protein array.

METHODS: Recombinant H pylori antigens, urease B subunit (UreB), vacuolating toxin A (VacA) and cytotoxin associated gene A protein (CagA), were prepared and immobilized in matrixes on nitrocellulose membrane by robotics to bind the specific immunoglobulin G (IgG) antibodies in serum. Staphylococcus protein A (SPA) labeled by colloid gold was used to integrate the immuno-complex and gave red color signal. The scanner based on charge-coupled device (CCD) could collect the image signal and convert it into digital signal.

RESULTS: When human IgG was printed on the membrane in increasing concentrations and incubated with immunogold, a linear dose response curve was obtained and the detection limit for IgG was about 0.025 ng. The cutoff values, which were defined as the mean grey level plus 3 times of standard deviation, were 27.183, 28.546 and 27.402, for anti-UreB IgG, anti-CagA IgG and anti-VacA IgG, respectively, as 400 human serum samples with negative H pylori antibodies were detected by the protein array. When 180 serum samples from patients in hospital were employed for detection of IgG against UreB, CagA and VacA, the sensitivity of the protein array was 93.4%, 95.4%, 96.0%, and the specificity was 94.8%, 94.4% and 97.5%, respectively, as compared with the results obtained by ELISA. The assay also showed high reproducibility, uniformity and stability, and the results were available within 30 min.

CONCLUSION: The protein array is a very practical method for rapid detection of multiple antibodies in serum samples. It is especially useful for large scale epidemiological investigation of the infection of H pylori.

Keywords: Helicobacter pylori; Protein array; Antibody; Immunogold