Myasthenia Gravis and Stem Cell Therapy

Stem Cell Therapy

Myasthenia gravis is a chronic neuromuscular disease that is characterized by the weakness of the muscles, and also leads to the quick fatigue of the voluntary muscles. This disease is caused by the alteration of the connection between the nerves and the muscles. It’s an autoimmune disease, in which the body immune system blocks and attacks the acetylcholine receptors. These receptors are usually located at the junction between the nerves and the muscles. Impulses and signals are sent from the muscles to the nerves through this receptor. However, in Myasthenia gravis, this connection is blocked, leading to the inability of the muscles to contract. Diagnosis is usually symptom-based, but can also be confirmed by performing some tests such as the blood test for the presence of antibodies to the receptors. Good news is that this disease can be treated. Physicians usually administer acetylcholinesterase inhibitors. Medications that suppress the immune system can also be prescribed. An example of this kind of drug is prednisone. Suppressing the immune system directly reducers the activities of the antibodies. The thymus gland can also be removed surgically, to improve the symptoms. Stem cell therapy has also been used in the treatment of this disease, especially in severe cases. Autologous hematopoietic stem cells are usually used for this purpose. This disease is not common in children, but prevalent in women, especially women under the age of forty. People affected with this disease can live a normal life if the disease is well managed.

What Are The Signs And Symptoms Of Myasthenia Gravis? 

Myasthenia gravis typically affects the voluntary muscles. The signs and symptoms of this disease worsen, as the individual affected uses the affected muscle. Muscle weakness associated with this disease is intermittent; it worsens for a while, then the patient feels relieved for a period. However, the symptoms do improve after rest. This disease worsens gradually and is capable of reaching its peak, just some years after the disease started. Below are some of the symptoms of the disease;

1. Eye muscles: This occurs in about two-thirds of the Myasthenia gravis cases. This is one of the initial symptoms of the disease. Patients might experience the drooping of the eyelids, and weakness of some of the eye muscles which could lead to double vision. The symptoms of the eyes usually become worse when patients perform activities such as driving, watching a movie in the cinema, studying and so on. In some cases, the muscle weakness is only present in the eyes, sparing the other muscles of the body. This isolated muscle weakness caused by this disease is called ocular myasthenia gravis. However, this type of isolated muscle weakness is mostly transient; it generally progresses to generalized muscle weakness after some years.
2. Eating: Myasthenia gravis also affects the muscles used in swallowing. This causes a lot of discomfort for the patients especially when they’re trying to swallow and digest food. This implies that some food would still remain in the mouth after the patient tries to swallow food or any other material. In addition, this disease impairs the function of the muscles of mastication. This would lead to problems and pain when chewing food. These symptoms are some of the earliest symptoms seen in a good percentage of Myasthenia gravis cases.
3. Difficulty speaking: The auto-antibodies can also attack the muscles used in phonation. This usually alters the way affected people speak. Their speech may sound nasal, slurred or forced. This depends entirely on the muscles affected.
4. Restricted facial expressions: Sometimes, the nerves controlling the facial expressions might be affected by this disease. This would eventually lead to the loss of facial expressions, such as smiling.
5. Muscles of the head and limbs: This disease can also cause the weakness of muscles of the head and the extremities. This disease tends to affect muscles of the upper limb, such as the arm muscles, as compared to the leg muscles.

What Are The Causes Of Myasthenia Gravis?

1. Autoimmunity: Myasthenia gravis is an autoimmune This is a condition in which the immune system fails to recognize the body cells and tissues, then proceeds to attacking and impairing its functions. This is what happens in this disease. Autoantibodies attacks and tries to destroy the acetylcholine receptors in the nerves and muscles. This would leave just a few receptors to perform the job of the transmission of impulses and signals, eventually leading to the weakness of the muscles.
2. Thymus gland: Some studies and researchers have suggested that thymus gland could be a key factor in the development of this disease. The thymus gland is located in the upper part of the chest, just behind the breastbone. The gland is part of the reticuloendothelial system. However, it has been observed that this organ might induce the production of antibodies that block the receptors communication between the nerves and the muscles. The thymus gland generally becomes smaller and might involute as one grows; however, this gland is usually large on people affected with this disease. In fact, some myasthenia gravis patients do have a tumour of the thymus gland. The symptoms of the disease can be improved by having the thymus gland removed surgically.
3. Other causes: Myasthenia gravis can also be transferred from a mother to her children. This condition is known as neonatal myasthenia gravis. Although this type of myasthenia gravis is very rare, there have been reported cases.

How Is This Disease Currently Treated?

Unlike most autoimmune diseases, myasthenia gravis can be cured. Below are some of the treatments that a physician could suggest;

1. Medications: There are some drugs that can improve the symptoms of this disease. Top of the list is cholinesterase inhibitor. This drug does not cure the disease, but it improves the symptoms. Other includes corticosteroids, an immunosuppressant.
2. Intravenous therapy
3. Surgery: A fraction of those affected by myasthenia gravis do have an abnormal enlargement of the thymus. This can be surgically removed.

Stem Cell Therapy and Myasthenia Gravis

Stem cell therapy has been successfully used in the treatment of this disease. This was done by doing autologous hematopoietic stem cell transplantation. This basically means that stem cells are extracted from the bone marrow of the patient, and then transplanted into the patients. Stem cells are unique cells, which are capable of differentiating into other types of cells. They can self-regenerate, and also have the ability to replace and repair any damaged or injured cell receptors, in this case.

References

BLICHFELDT-LAURIDSEN, L. and HANSEN, B. (2011). Anesthesia and myasthenia gravis. Acta Anaesthesiologica Scandinavica, 56(1), pp.17-22.

Tsutsumi, Y., Kamiishi, T., Kikuchi, R., Ito, S., Matsuoka, S. and Teshima, T. (2017). Myasthenia gravis after allogeneic bone marrow transplantation: A case report and literature review. Hematology/Oncology and Stem Cell Therapy.

Unal, S., Sag, E., Kuskonmaz, B., Kesici, S., Bayrakci, B., Ayvaz, D., Tezcan, I., Yalnızoglu, D. and Uckan, D. (2013). Successful treatment of severe myasthenia gravis developed after allogeneic hematopoietic stem cell transplantation with plasma exchange and rituximab. Pediatric Blood & Cancer, 61(5), pp.928-930.