Sugar chains located on cell surface or in the extra-cellar matrix, as a form of glycoprotein, glycolipid, proteoglycan, or glycosaminoglycan (GAG), are responsible for many biological functions and play crucial roles in cellular binding and signaling, which includes the infection of microorganism or the metastasis of cancer. Therefore, sugar chains are being recognized as one of the most important research subjects in life science for the next generation of post-genome research. 

         For the research of sugar chains, we developed two types of “Sugar Chip (SC)”, and “Sugar-chain immobilized Gold-Nanoparticle (SGNP)”, in which sugar chains are immobilized on the gold coated glass slide (chip) or the top of optical-fiber, or on the gold nano-particle (Figure). 

        Using these tools, we have developed a novel diagnostic system for highly sensitive and accurate detection of viruses including SARS-CoV-2, and single chain antibodies (scFvs) specific for GAG on the surface of cancer cells or for specific sugar chain structures known as tumor-associated carbohydrate antigen. The scFvs were then incorporated into Natural killer (NK) cells taward the development of cellular immunotherapy. The past and on-going results will be discussed.