With tremendous advances in carbohydrate-based vaccine design and construction, glycoconjugate constructs with improved safety and efficacy are greatly required. With Ph.D. level scientists and substantial experience in glycoscience, Creative Biolabs provides comprehensive R&D services in the development of carbohydrate-based vaccine. We are dedicated to offering high-quality custom oligosaccharides synthesis and conjugation services to meet our clients’ R&D timeline and budget.
Cell surface glycans on many infectious agents are attributed to playing an important role in pathogenesis. With technological advances in glycobiology, carbohydrate antigens are paid more and more attention as key targets in developing safe and effective vaccines to combat viral infections, bacterial infections, and cancer, etc. However, carbohydrates alone are poorly immunogenic as they do not bind strongly to the MHCII complex, thus failing to elicit T-cell immunity. Current strategies for the production of carbohydrate-based vaccines require conjugation of the low immunogenic carbohydrate antigen through a linker to a protein carrier for optimal antibody response. To achieve desired immunological responses, carbohydrates have been conjugated to carrier proteins, such as keyhole limpet hemocyanin (KLH), bovine serum albumin (BSA), diphtheria toxin mutant (CRM197), diphtheria toxoid (DT), tetanus toxoid (TT), ovalbumin, meningococcal outer membrane protein complex (OMPC), Hemophilus influenzae protein D, human serum albumin (HSA), Pseudomonas aeruginosa exotoxin A (rEPA) and zwitterionic polysaccharides (ZPSs), etc. So far, carbohydrate-based vaccines against microbial pathogens constitute one of the most representative examples of the promise of glycans in clinically relevant applications.
Fig.1 Synthetic carbohydrate-based vaccines against microbial pathogens. (Fernández-Tejada, 2015)
Naturally derived glycans like cell-surface polysaccharides from bacteria, viruses, and parasites have served as valuable antigenic targets for vaccine development. Besides naturally derived glycans, we have developed cutting-edge platforms for Custom Glycan Synthesis, using chemical and chemoenzymatic methods.
For conjugation, covalent linkage of polysaccharides to carrier proteins or peptides is generally achieved by targeting the amines of lysines, the carboxylic groups of aspartic/glutamic acids or the sulfhydryls of cysteines. Our seasoned scientists are proficient in employing diverse strategies for the conjugation of carbohydrate antigens to carrier proteins or peptides to further improve the safety and efficacy of glycovaccines. Our strategies include non-specific methods and site-specific methods, summarized as below.
Creative Biolabs focuses on the general structure of a glycoconjugate vaccine consists of carbohydrate B-cell epitope and a carrier protein or peptide providing the T-helper epitope to elicit T-cell immunity. More complex constructs based on multivalent exposition of carbohydrates have also been developed.
Rational designed, structurally defined, and fully synthetic carbohydrate antigens offer a promising alternative for developing future carbohydrate-based vaccines. Creative Biolabs is committed to providing high-quality oligosaccharides synthesis and conjugation services to promote the progress of carbohydrate-based vaccine development projects. For more detailed information, please feel free to contact us or directly send us an inquiry.