Autologous hematopoietic stem cell transplantation (aHSCT) is a type of bone marrow transplant that aims to ‘reset’ the immune system in people with Multiple Sclerosis. It is the immune system that is responsible for passing through the blood brain barrier, and damaging the central nervous system (brain, spinal cord and optic nerve) causing lesions or plaques. Autologous means the stem cells are derived from a person’s own body.
The process of aHSCT begins by mobilizing stem cells (by the use of a specific drug) to leave the bone marrow, and move into the peripheral blood system where they can be later collected and stored. Patients will then receive high dose chemotherapy intended to kill “auto-toxic” immune cells.
Once enough stem cells are present in the blood, they are then harvested by means of apheresis, a procedure similar to dialysis. The patient’s blood is passed through a filtering machine by IV. The stem cells are stored (or frozen).
Then more high dose chemotherapy is administered to eliminate the rest of the immune system. The drugs cannot selectively destroy the “auto-toxic” immune cells responsible for causing MS, thus, in the process other forms of dividing immune cells are eliminated. This leaves the patient in a temporary immunodeficiency state.
One’s own stored stem cells are then given back, through an infusion. This “transplant” of one’s stem cells allows the body to form new immune cells in order to restore their immune system. There is a period of isolation until the body can rebuild a baseline of immunity.
The overall recovery period can be six months to two years. A person may need to have extensive rehabilitation after the treatment.
The goal of the entire HSCT treatment is to stop the immune system from causing damage of self. New research has been shown to help or completely stop relapses in people with relapsing remitting MS, in cases where all other medicines did not work.