Tweaking the immune system: gene therapy-assisted autologous haematopoietic stem cell transplantation as a treatment for autoimmune disease.

Autoimmune diseases represent a major challenge for medical research. The aberrant self-recognition by the immune system leads to a range of pathologies for which cures have not been forthcoming. Treatments are commonly non-specific and often lead to unwanted side-effects. A number of strategies are currently being explored to tackle autoimmunity; aimed at eliminating existing pathogenic clones and the induction of immune tolerance through resetting or regulating the immune system. Autologous haematopoietic stem cell transplantation (HSCT) is one such strategy and is being trailed in a number of autoimmune diseases. However, a common feature of this strategy is disease relapse and may indicate incomplete tolerance mechanisms. It is well known that bone marrow derived cells have a major influence on immune tolerance. It is also well documented that ectopic expression of antigens within the immune system can promote robust tolerance. This review considers these observations in the context of promoting a strategy involving genetic manipulation of haematopoietic stem cells together with HSCT to induce immune tolerance and tackle autoimmunity.