Project description:The aim of the study was to determine the epitope targeted by 31E10/E7 mouse monoclonal antibody (mAb) and the cross-reactivity to linear peptide epitopes of 10 different Neisserial Heparin Binding Antigen (NHBA) variants. mAb 31E10/E7 was diluted at 1:200 and incubated on a custom PepStar Peptide Microarray platform printed with 560 different peptides in three independent experiments.
Project description:The aim of the study was to determine the epitope targeted by 31E10/E7 mouse monoclonal antibody (mAb). mAb 31E10/E7 was diluted at 1:2000 and incubated on a non-commercial Protein Microarray platform printed with NHBA specific recombinant protein fragments and full length NHBA of different variants.
Project description:The aim of the study was to determine the epitope targeted by four different HumAbs and the cross-reactivity to linear peptide epitopes of 10 different Neisserial Heparin Binding Antigen (NHBA) variants. the HumAbs were diluted at 1:60 and incubated on a custom PepStar Peptide Microarray platform printed with 561 different peptides.
Project description:We explore here the potential of a newly described technology, which is named PROFILER and is based on next generation sequencing of gene-specific lambda phage-displayed libraries, to rapidly and accurately map monoclonal antibody (mAb) epitopes. For this purpose, we used a novel mAb (designated 31E10/E7) directed against Neisserial Heparin-Binding Antigen (NHBA), a component of the anti-group B meningococcus Bexsero® vaccine. An NHBA phage-displayed library was affinity-selected with mAb 31E10/E7, followed by massive sequencing of the inserts present in antibody-selected phage pools. Insert analysis identified an amino acid stretch (D91-A128) in the N-terminal domain, which was shared by all of the mAb-enriched fragments. Moreover, a recombinant fragment encompassing this sequence could recapitulate the immunoreactivity of the entire NHBA molecule against mAb 31E10/E7. These results were confirmed using a panel of overlapping recombinant fragments derived from the NHBA vaccine variant and a set of chemically synthetized peptides covering the 10 most frequent antigenic variants. Furthermore, hydrogen-deuterium exchange mass-spectrometry analysis of the NHBA-mAb 31E10/E7 complex was also compatible with mapping of the epitope to the D91-A128 region. Collectively, these results indicate that the PROFILER technology can reliably identify epitope-containing antigenic fragments and requires considerably less work, time and reagents than other epitope mapping methods.
Project description:The aim of the study was to determine the epitope targeted by four different HumAbs and the cross-reactivity to linear peptide epitopes of 5 different Neisserial adesin A (NadA) variants. the HumAbs were diluted at 1:200 and incubated on a custom PepStar Peptide Microarray platform printed with 348 different peptides.
Project description:The aim of the study was to determine the epitope targeted by 5 different HumAbs and the cross-reactivity to linear peptide epitopes of 12 different factor H binding protein (fHbp) variants. The HumAbs were diluted at 1:200 and incubated on a custom PepStar Peptide Microarray platform printed with 363 different peptides.
Project description:A series of systematically modified cyclic AMP (cAMP) analogues, including newly synthesized benzimidazole ribofuranosyl 3',5'-monophosphates was used to map the essential molecular interactions between cAMP and the monoclonal antibody 4/2C2 (mab 4/2C2) directed against 2'-O-succinoyl cAMP [Colling, Gilles, Nass, Moka & Jaenicke (1988) Second Messengers Phosphoproteins 12, 123-133]. Its paratope binds the purine base in syn conformation by dipole-dipole interactions and hydrophobic forces and/or stacking interactions. The ribose phosphate moiety is recognized by a combination of charge interactions and H-bonds to the exocyclic and the 5'-oxygen atoms and a hydrophobic interaction at the 2'-position. There is no regioselectivity for the exocyclic oxygen atoms. Compared with the known types of binding, mab 4/2C2 thus shows a new combination of molecular interactions which may be the basis of its strikingly specific recognition and binding of the cyclic adenylates. On this account mab 4/2C2 may become an important tool in studies on cAMP metabolism.
Project description:High quality, well-validated antibodies are needed to mitigate irreproducibility and clarify conflicting data in science. We describe an epitope-directed monoclonal antibody (mAb) production method that addresses issues of antibody quality, validation and utility. The workflow is illustrated by generating mAbs against multiple in silico-predicted epitopes on human ankyrin repeat domain 1 (hANKRD1) in a single hybridoma production cycle. Antigenic peptides (13-24 residues long) presented as three-copy inserts on the surface exposed loop of a thioredoxin carrier produced high affinity mAbs that are reactive to native and denatured hANKRD1. ELISA assay miniaturization afforded by novel DEXT microplates allowed rapid hybridoma screening with concomitant epitope identification. Antibodies against spatially distant sites on hANKRD1 facilitated validation schemes applicable to two-site ELISA, western blotting and immunocytochemistry. The use of short antigenic peptides of known sequence facilitated direct epitope mapping crucial for antibody characterization. This robust method motivates its ready adoption for other protein targets.