The immune system faces the difficult challenge of discerning between “self” and “non-self” and simultaneously defending against microbial pathogens. Although self-reactive T cells can be deleted in the thymus, the elimination process is often incomplete, and therefore activation of regulatory mechanisms in peripheral tissues is required in order to dampen potentially harmful responses. Homeostatic signals delivered in the form of immunosuppressive cytokines or inhibitory receptors are integrated into tolerogenic circuits that sustain peripheral tolerance mechanisms. Numerous regulatory programs have been identified that contribute to the restoration of homeostasis at the conclusion of immune responses and to safeguarding against the detrimental effects of chronic inflammation and autoimmune pathology. In this lecture we will review the role of endogenous galectins and specific N- and O-glycans interaction that together promote regulatory signals that control immune cell homeostasis. We will also discuss the mechanisms by which glycan-dependent regulatory programs integrate into canonical circuits that amplify or silence immune responses related to autoimmunity.
Disclosure of Interest None Declared