Lymphocyte adhesion and autoimmunity

Aberrant lymphocytes signaling is one of the numerous mechanisms thought to be responsible for the pathogenesis of autoimmune diseases. One of the most successful approaches to the treatment of autoimmunity is through targeting of lymphocytes, whose multiple targetable functions include proliferation, cytokine secretion, and migration. The adhesion process is a critical step, not only for migration but also for their communication with antigen-presenting cells, and is therefore a clear target for therapy. This manuscript will discuss the migration of T cells, which are at the heart of many autoimmune responses. We will review the importance of increasing our comprehension of these events, focusing on migration since they enclose a multitude of potential therapeutic targets for autoimmunity. The interface between lymphocytes and antigen presenting cells and the formation of the immunological synapse will be reported in detail. We will address the following questions: What enables T cells to migrate to sites of injury, and what are the options to intervene? What is the contribution of co-receptors to T cell adhesion? How can we manipulate this knowledge for therapeutic purposes? Finally, we will review the latest data regarding current and future therapeutics that target the adhesion process, describing their strength and weaknesses.