HNK-1 carbohydrate, an attractive unique glyco-epitope

The HNK-1 carbohydrate antigen, which recognized by a monoclonal antibody HNK-1, was originally noticed as a maker of human natural killer (HNK) cells. Subsequent studies revealed that HNK-1 carbohydrate was highly expressed in the nervous system and was commonly expressed on cell adhesion molecules belonging to the immunoglobulin superfamily. Therefore, it was suggested the involvement of HNK-1 carbohydrate in migration of neural crest cells, adhesion of neurons to glial cells, and axon outgrowth. I was interested in this epitope and investigated the biosynthetic enzymes for this epitope. I fortunately received the JSCR Young Investigator Award 1998. In this review, I illustrated a series of our studies including recent findings about the HNK-1 carbohydrate.