Autologous hematopoietic stem cell transplantation in autoimmune diseases – a brand new standard. Where do we go from here?

摘要

For many years autologous hematopoietic stem cell transplantation (AHSCT) has been viewed as experimental treatment of severe autoimmune diseases. However, as randomized trials have finished we are now facing a?new reality – autologous hematopoietic stem cell transplantation has been acknowledged by major medical societies as standard treatment of severe autoimmune diseases [1–3]. How does AHSCT work in autoimmune diseases? First the hematopoietic stem cells are collected from the patient. Second conditioning is given – a?strong chemotherapy that can eradicate the underlying autoimmune disease. How strong is this chemotherapy? To put it into perspective: the systemic sclerosis patient who gets 1 gram of cyclophosphamide in monthly infusions if transplanted will get 24 grams of cyclophosphamide within 4 days together with additional antithymocyte globulin – and this is one of the least intensive approaches that we use in hematopoietic stem cell transplantation. Third step – the infusion of hematopoietic stem cells. The therapeutic effect is achieved by chemotherapy; the stem cells just help to regenerate the hematopoietic system. The exact mechanism of action is still not fully understood – is it the restart or reset of immune responses or is it a?shift towards a?more tolerant immune system? More research is needed to answer this question. So where are we now with this approach? There two autoimmune disease in which AHSCT has just been recognized as standard. The first disease in which AHSCT has reached the status of standard is systemic sclerosis [1]. EULAR was first to acknowledge that there are enough data on AHSCT to set it as standard for severe cases of systemic sclerosis. Rheumatologists were the first and so far the only society other than hematologists to acknowledge that AHSCT works. The second disease is multiple sclerosis. The European Society for Blood and Marrow Transplantation and the American Society for Blood and Marrow Transplantation have just named AHSCT as the standard treatment of relapsing remitting MS on the basis of a?few randomized trials and multiple one arm trials [2, 3]. What is the situation with other autoimmune diseases? AHSCT can be a?clinical option in other autoimmune diseases – especially in refractory cases of systemic lupus, Crohn’s disease, chronic demyelinating polyneuropathy, neuromyelitis optica and other autoimmune conditions [3]. It is very unlikely that we will see many...