Immune biasing by helminth glycans.

The ability of helminth parasites to drive polarized Th2 responses has been known for some time. Interestingly, many recent studies have shown that helminth-expressed glycan activation of host immune cells accounts for much of the anti-inflammatory and Th2-biasing observed. This microreview attempts to cover the biology of expression of immunomodulatory glycans in various helminth parasites, the immune cells they interact with including the production of cytokines, chemokines and antibodies. We also discuss the potential cell surface receptors which are capable of binding certain glycans and the known mech-anisms which ultimately lead to production of anti-inflammatory mediators as well as polarizing CD4+ T-cell responses to Th2-type in the host. Lastly, we discuss a novel mechanism for activation of antigen-presenting cells by a specific helminth glycan that leads to maturation of Type 2 dendritic cells.