Identification and characterization of peptide mimics of blood group A antigen.
In order to investigate peptide mimics of carbohydrate blood group A antigen, a phage display 12-mer peptide library was screened with a monoclonal antibody against blood group A antigen, NaM87-1F6. The antibody-binding properties of the selected phage peptides were evaluated by phage ELISA and phage capture assay. The peptides were co-expressed as glutathione S-transferase (GST) fusion proteins. RBC agglutination inhibition assay was performed to assess the natural blood group A antigen-mimicking ability of the fusion proteins. The results showed that seven phage clones selected bound to NaM87-1F6 specifically, among which, 6 clones bore the same peptide sequence, EYWYCGMNRTGC and another harbored a different one QIWYERTLPFTF. The two peptides were successfully expressed at the N terminal of GST protein. Both of the fusion proteins inhibited the RBC agglutination mediated by anti-A serum in a concentration-dependent manner. These results suggested that the fusion proteins based on the selected peptides could mimic the blood group A antigen and might be used as anti-A antibody-adsorbing materials when immunoabsorption was applied in ABO incompatible transplantation.
Tang
Zhaoming
Z
Department of Laboratory Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China. toumin@126.com
Wang
Lin
L
Hu
Lihua
L
Li
Yirong
Y
Cui
Tianpen
T
Xiong
Juan
J
Dou
Lifang
L
D000327:Adsorption; D001435:Bacteriophages; D001789:Blood Group Antigens / Q000737:chemistry*; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000737:chemistry; D005982:Glutathione Transferase / Q000378:metabolism; D006801:Humans; D019151:Peptide Library; D010455:Peptides / Q000737:chemistry*; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000737:chemistry
D001789:Blood Group Antigens; D000939:Epitopes; D019151:Peptide Library; D010455:Peptides; D011993:Recombinant Fusion Proteins; D005982:Glutathione Transferase