Preserving β cells in type 1 diabetes mellitus:: The role of immunological tolerance

Type 1 diabetes mellitus (T1DM) is characterized by an autoimmune attack on beta cells of (lie islets of Langerhans. This immunological attack is mediated by effector T-lymphocytes and results in the destruction of the beta cells. One approach to abrogating the immunological attack is to use immunosuppressive treatments. Such treatments tend to broadly suppress the immune system. A better approach is to develop treatments that induce tolerance. Autoimmune diseases are associated with the presence of inadequate numbers of functionally active regulatory T cells (Tregs). Tregs call induce a state of immunological tolerance and suppress the inflammation and destruction Of target tissues. Teplizumab, also known as hOKT3 gamma 1 (Ala-Ala), is a humanized monoclonal antibody that induces Tregs. In clinical trials, treatment with this antibody preserved insulin production and improved metabolic control during the first year of T1DM. A pivotal Multinational trial is in progress to determine the efficacy and safety of teplizumab in the treatment of new onset T1DM.