A peptide mimetic of Gal-alpha 1,3-Gal is able to block human natural antibodies.
The carbohydrate of Gal-alpha1,3-Gal is thought to be the major antigenic epitope present on pig vascular endothelium. The peptides that mimic the binding of antigenic epitope (Gal-alpha1,3-Gal) to lectin BS-I-B4 were identified from screening a filamentous phage-displayed random library. A phage bearing the peptide NCVSPYWCEPLAPSARA has been identified to bind the lectin strongly. Melibiose was able to inhibit the binding of the human natural anti-alpha Gal antibody to the peptide competitively. Our experiments show that the peptide mimetic of Gal-alpha1,3-Gal is able to inhibit the agglutination of pig RBCs by human natural antibody or lectin BS-I-B4. The peptide inhibitor of human natural antibodies may prove useful in pig-to-human xenotransplantation.
Zhan
Jinbiao
J
Department of Biochemistry, Zhejiang University Medical School, Zhejiang Province, Hangzhou 310006, PR China. jzhan2k@cmm.zju.edu.cn
Xia
Zheng
Z
Xu
Linhai
L
Yan
Zhikun
Z
Wang
Keyi
K
D000595:Amino Acid Sequence; D000906:Antibodies / Q000276:immunology*; D001483:Base Sequence; D017931:DNA Primers; D005690:Galactose / Q000737:chemistry*; D006386:Hemagglutination Tests; D006801:Humans; D008553:Melibiose / Q000737:chemistry; D018716:Molecular Mimicry; D008969:Molecular Sequence Data
D000906:Antibodies; D017931:DNA Primers; D008553:Melibiose; D005690:Galactose