Breakthroughs in genomic sequencing led to the realization that the complexity of higher organisms is encoded in a surprisingly small number of genes. The next major challenge in understanding biological diversity is glycomics, the systematic study of all glycan structures of a given cell type or organism. Glycosylation is by far the most complex form of post translational modification encompassing a wide range of biomolecules in both micro- and macro-organisms. Glycan expression not only varies by different cell types, but also significantly changes during cell development and differentiation. Interestingly, glycans carry more information per unit weight than either proteins or nucleic acids and as such, represent a major dynamic source of variation.
As a result of the enormous range of structural diversity, glycans play a key role in both innate and adaptive immunity. Studies have revealed that glycosylation is responsible for pathogen recognition (epitope/antigen markers), modulation of the innate immune system and control of immune cell homeostasis and inflammation. Many pathogens express glycans on their cell surface, causing the immune system to evolve mechanisms that recognize these glycan antennae. Furthermore, pathogenic glycans can be similar to mammalian glycans; this so called “molecular mimicry” is thought to be one of the causes of autoimmune disease.
It is believed almost all human diseases are genetic in origin. Genetic research has revealed the cause of many diseases such as cystic fibrosis, Duchenne muscular dystrophy and Tay Sachs. However, the inherited genetic causes of autoimmune disease are for the most part unknown, not consistently replicated or accepted by the community. Reasons for genetic elusiveness of autoimmune disease most likely derive from the complexity of genetic polymorphisms that causes these diseases, and the large influence of the environment on autoimmune diseases. Environmental influences may be microbial, chemical or even nutritional in origin. Measurement of the immune response to glycans provides the advantage of evaluating both the genetic susceptibility of the individual combined with the environmental effects triggering these changes.
We also believe that for prognosis of autoimmune diseases, glycan-based diagnostic tests contain the following advantages over the use of proteins, DNA or even RNA: