Detection of subtle differences in analogous viral capsid proteins by allowing unrestricted specific interaction in solution competition ELISA.
Assay artifacts were reported in plate-based immuoassays during the assessment of specific molecular interactions owing to the surface induced aggregation/conformational changes. To circumvent surface adsorption and associated artifacts, we used a solution competition ELISA by allowing unrestricted interaction between binding partners to occur in solution for better discrimination between epitopes with subtle differences. A difference of two orders of magnitude in binding to neutralizing antibodies for two truncated versions of the hepatitis E virus capsid protein was observed, while other assays showed comparable antigenicity with the same monoclonal antibodies. Discrimination of epitopes with high degree resemblance in analogous viral capsid proteins was demonstrated quantitatively based on their specific interactions. Therefore, the solution competition ELISA is a method of choice when the detection of subtle differences of two highly analogous proteins is desired.
State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen, Fujian 361005, PR China; School of Public Health, Xiamen University, Xiamen, Fujian 361005, PR China. Electronic address: caolu@stu.xmu.edu.cn.
Lu
L
Cao
State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen, Fujian 361005, PR China; School of Public Health, Xiamen University, Xiamen, Fujian 361005, PR China. Electronic address: wxinc35@163.com.
Xin
X
Wang
State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen, Fujian 361005, PR China; School of Public Health, Xiamen University, Xiamen, Fujian 361005, PR China. Electronic address: mjfang@xmu.edu.cn.
Mujin
M
Fang
State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen, Fujian 361005, PR China; School of Public Health, Xiamen University, Xiamen, Fujian 361005, PR China; School of Life Science, Xiamen University, Xiamen, Fujian 361005, PR China. Electronic address: nsxia@xmu.edu.cn.
Ningshao
N
Xia
State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Diseases, Xiamen University, Xiamen, Fujian 361005, PR China; School of Public Health, Xiamen University, Xiamen, Fujian 361005, PR China. Electronic address: qinjian_zhao@xmu.edu.cn.
Qinjian
Q
Zhao
D000911:Antibodies, Monoclonal / Q000276:immunology / Q000378:metabolism; D057134:Antibodies, Neutralizing / Q000276:immunology / Q000378:metabolism; D000914:Antibodies, Viral / Q000276:immunology* / Q000378:metabolism*; D036022:Capsid Proteins / Q000276:immunology* / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D000939:Epitopes / Q000378:metabolism; D016752:Hepatitis E virus / Q000276:immunology*; D011485:Protein Binding
D000911:Antibodies, Monoclonal; D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D036022:Capsid Proteins; D000939:Epitopes
Antigen-antibody interaction; Binding analysis; Hepatitis E virus; Monoclonal antibody; Solution interaction; Viral capsid protein