Autologous hematopoietic stem cell transplantation (AHSCT) was proposed 20 years
ago as an alternative therapeutic approach for patients with severe and refractory
autoimmune diseases. Since then, this innovative therapy has been successfully
used to treat several autoimmune diseases, such as neurological disorders
(Multiple Sclerosis), connective tissue diseases (Systemic Sclerosis and Systemic
Lupus Erythematous), gastrointestinal inflammatory diseases (Crohn’s Disease) and
others (Juvenile Arthritis, Type 1 Diabetes, Vasculitis).
Experience in phase I-II and III clinical trials over the years has led to increased safety
and efficacy of this procedure. Recent studies have demonstrated superior therapeutic
efficacy of AHSCT versus conventional therapies, showing that transplantation can
induce long-term disease remission in the absence of any further immunosuppressive
treatment. Immune monitoring studies have showed that AHSCT is able to reduce
the inflammatory milieu, to reset the immune balance and to promote the generation
of a new auto-tolerant immune repertoire. However, some patients fail to remain
in remission, and disease is re-activated after some time post-transplantation. This
scenario indicates that further immunological interventions may be still required to
improve AHSCT efficacy. Clear understanding of the operating immune mechanisms
that contribute to specific clinical outcomes is vital to enable improvement of AHSCT
protocols for autoimmune diseases.