1Institute of Biochemical Sciences, National Taiwan University, Taipei 2Genomics Research Center, Academia Sinica, Taipei
Recently, many broadly neutralizing antibodies (bNAbs) were isolated from HIV positive donors. These antibodieswere shown to be potent in neutralizing primary HIV-1 strains across clades and interact directly with HIV glycan coat. The difficulty of designing HIV-1 vaccine is to exploit immunogens which can induce antibodies with broadly neutralizing activities. To understand the interaction between bNAbs and the gp120 glycan shield on HIV, we synthesized a series of diverse high-mannose, hybrid, and complex type N-glycans by chemical and chemo-enzymatic methods to form a complete panel in a glycan array for bNAbs specificity studies.We utilized aluminum oxide coated glass slide to enhance the weak signal of interactions between bNAbs and glycans which cannot be detected in general glycan array. Our results showed that PG9 and PG16 distinctly bind to hybrid and bi-antennary complex type glycans with a-2,6 linkage at its capping sialic acid respectively. We further discovered glycan epitopes of other bNAbs PGT141, PGT142, PGT143, PGT144, and PGT145.
