Amyotrophic lateral sclerosis (ALS) is a progressive neurological condition characterized by the degeneration of nerve cells in the brain and spinal cord. An uncontrolled and misdirected inflammatory response by the body’s immune system is thought to be one of the factors that cause damage to the neurons.

Cell therapy using regulatory T-cells (Tregs) recently has shown promise in suppressing inflammation and slowing the progression of ALS.

Tregs and ALS

Regulatory T-cells are a type of white blood cells that function to suppress the body’s immune response and prevent unnecessary inflammation once an infection has been cleared. These T-cells also can enter the brain and the spinal cord to mitigate neuroinflammation.

ALS patients were found to have lower levels of Tregs in their blood compared with healthy people in a study published in the journal JAMA Neurology. The study also showed that the rate of disease progression is faster in ALS patients with lower Treg levels. Further, in a mouse model of ALS, increasing the number of Tregs in the blood slowed the progression of the disease.

Scientists now think there is an inverse link between levels of Tregs and the rate of ALS progression. This suggests that enhancing the Tregs level in people with ALS could delay the disease’s progression.

Tregs in clinical trials

A small Phase 1 clinical trial (NCT03241784) assessed the safety and tolerability of Treg infusions in three ALS patients, ages 46 to 56. They first underwent leukapheresis, a process in which specific components such as white blood cells are removed from the blood, and its remaining contents are reintroduced into the body. This procedure allowed Tregs to be isolated from the white blood cell. The researchers developed a protocol to multiply these Tregs in the laboratory.

Each patient then received eight intravenous infusions of their own Tregs over a period of six months. The three also received injections of interleukin-2 (IL-2) — a protein that helps infused Tregs survive in the body — three times per week for the duration of the study.

The team monitored Treg levels in the patients’ bodies and assessed their ability to suppress inflammation. The participants were closely observed for any adverse effects.

The results showed that Treg infusions were safe and well-tolerated by all three patients. After each infusion, Treg numbers, as well as their function, was significantly enhanced. The improved Treg numbers also preserved the participants’ functional ability by slowing their functional decline. The larger the increase in Tregs, the slower the loss of function and rate of ALS progression.


ALS News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified healthcare providers with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.