Molecular Characterization of Two Monoclonal Antibodies against the Same Epitope on B-Cell Receptor Associated Protein 31
| Autor: | Hwang, HJ, Shin, S, Kim, WT, Park, H, Ryu, CJ, Gill, AC, Kim, MY, Jung, HS |
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| Rok vydání: | 2016 |
| Předmět: |
0301 basic medicine
Protein Conformation Antibody Affinity Immunoglobulin Variable Region lcsh:Medicine Gene Expression Complementarity determining region Protein Sequencing Endoplasmic Reticulum Physical Chemistry Biochemistry Epitope Epitopes Mice Protein structure Antibody Specificity Biochemical Simulations Cloning Molecular Enzyme-Linked Immunoassays lcsh:Science B-Lymphocytes Multidisciplinary Crystallography Secretory Pathway biology Chemistry Physics Chromatographic Techniques Antibodies Monoclonal Condensed Matter Physics Molecular Docking Simulation Amino Acid Specific Chromatography Cell Processes Physical Sciences Crystal Structure Antibody Cellular Structures and Organelles Hydrophobic and Hydrophilic Interactions Sequence Analysis Protein Binding Research Article medicine.drug_class Receptors Antigen B-Cell Molecular Dynamics Simulation Monoclonal antibody Research and Analysis Methods 03 medical and health sciences Amino Acid Sequence Analysis medicine Escherichia coli Glutathione Chromatography Animals Humans Solid State Physics Amino Acid Sequence Immunoassays Molecular Biology Techniques Sequencing Techniques Molecular Biology Binding selectivity Linear epitope Chemical Bonding Affinity Chromatography lcsh:R Membrane Proteins Biology and Life Sciences Computational Biology Hydrogen Bonding Cell Biology Complementarity Determining Regions 030104 developmental biology biology.protein Immunologic Techniques lcsh:Q Paratope Binding Sites Antibody Sequence Alignment |
| Zdroj: | PLoS ONE PLOS ONE(11): 12 PLoS ONE, Vol 11, Iss 12, p e0167527 (2016) |
| ISSN: | 1932-6203 |
| Popis: | Previously, we showed that B-cell receptor associated protein 31 (BAP31), an endoplasmic reticulum (ER) membrane chaperone, is also expressed on the cell surface by two monoclonal antibodies (MAbs) 297-D4 and 144-A8. Both MAbs recognize the same linear epitope on the C-terminal domain of BAP31, although they were independently established. Here, flow cytometric analysis showed that 144-A8 had additional binding properties to some cells, as compared to 297-D4. Quantitative antigen binding assays also showed that 144-A8 had higher antigen binding capacity than 297-D4. Affinity measurement revealed that 144-A8 had 1.54-fold higher binding affinity than 297-D4. Analysis of the heavy- and light-chain variable region sequences of two MAbs revealed that both MAbs belonged to the same heavy chain (Igh-V3660 VH3) and light chain subgroup (IGKV21) with just two amino acid differences in each framework region, indicating that both MAbs arise from the same germline origin. Seven amino acid differences were found between the complementarity determining regions (CDRs) of the two MAbs. Molecular modeling of the epitope-paratope complexes revealed that the epitope appeared to reside in closer proximity to the CDRs of 144-A8 than to those of 297-D4 with the stronger hydrogen bond interactions with the former than the latter. More interestingly, an additional hydrophobic interaction appeared to be established between the leucine residue of epitope and the paratope of 144-A8, due to the substitution of H-Tyr101 for H-Phe101 in 144-A8. Thus, the different binding specificity and affinity of 144-A8 appeared to be due to the different hydrogen bonds and hydrophobic interaction induced by the alterations of amino acids in CDRs of 144-A8. The results provide molecular insights into how the binding specificities and affinities of antibodies evolve with the same epitope in different microenvironments. |
| Databáze: | OpenAIRE |
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