The Risks of Current Approaches to Rebooting the Immune System

The present approaches to rebooting the immune system have shown considerable promise in treatment of autoimmune diseases such as multiple sclerosis. Unfortunately the current methods of immune destruction involve chemotherapy, which is a damaging process in and of itself, and there is as yet too little attention being given to protection against infection in the period while the immune system is absent or near-completely suppressed. The risks are significant, and until addressed mean that this remains useful only for patients who will suffer worse absent the therapy.

Both of the major risks noted above could be addressed in the near future, however. Firstly through the development of targeted cell destruction methods with minimal side-effects, such as that currently pioneered by Oisin Biotechnologies, and secondly through delivery of new immune cells generated from the patient's own cells. It is in all our interests to see a broadening of immune reboot work, as this class of therapy could help clear out the malfunctioning and misconfigured cells from an age-damaged immune system, producing a partial rejuvenation of immune function in the elderly.

A type of treatment for multiple sclerosis that 'resets' the immune system may stop progression of the disease in nearly half of patients. In a new study the treatment prevented symptoms of severe disease from worsening for five years, in 46 per cent of patients. However, as the treatment involves aggressive chemotherapy, the researchers stress the procedure carries significant risk. The treatment in the current study, called autologous hematopoietic stem cell transplantation (AHSCT), was given to patients with advanced forms of the disease that had failed to respond to other medications.

The one-off treatment aims to prevent the immune system from attacking the nerve cells. All immune system cells are made from stem cells in the bone marrow. In the treatment, a patient is given a drug that encourages stem cells to move from the bone marrow into the blood stream, and these cells are then removed from the body. The patient then receives high-dose chemotherapy that kills any remaining immune cells. The patient's stem cells are then transfused back into their body to re-grow their immune system. Previous studies have suggested this 'resets' the immune system, and stops it from attacking the nerve cells.

However, because the treatment involves aggressive chemotherapy that inactivates the immune system for a short period of time, some patients died from infections. Out of the 281 patients who received the treatment in the study, eight died in the 100 days following the treatment. Older patients, and those with the most severe forms of the disease, were found to have a higher risk of death. "In this study, which is the largest long-term follow-up study of this procedure, we've shown we can 'freeze' a patient's disease - and stop it from becoming worse, for up to five years. However, we must take into account that the treatment carries a small risk of death, and this is a disease that is not immediately life-threatening."



Newly discovered immune cell type protects against lung infections during chemotherapy

"Chemotherapy drugs kill dividing cells, including cells in the bone marrow that give rise to different immune cells. That can lead to a dramatic reduction in white blood cells, including the neutrophils that play a central role in combating bacterial and other infections that are a common complication of cancer chemotherapy.

Researchers showed the macrophages identified in this study were produced in the lungs following vaccination rather than the bone marrow. Researchers called the newly recognized cell type vaccine-induced macrophages (ViMs). Once generated, ViMs were maintained in the lungs by cell division. Importantly, unlike other immune cells types, the size of the ViMs population remained stable during chemotherapy. This newly recognized cell type also showed enhanced anti-bacterial activity in mice that lacked neutrophils due to chemotherapy."

Posted by: Jim at February 21st, 2017 9:35 AM

Is there any progress on thymus regeneration ?

Posted by: Martin S. at February 21st, 2017 2:33 PM
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