Abstract

Autoimmune diseases, including SSc, are prevalent, affecting autologous connective tissues and caused by the breakdown of self-tolerance mechanisms of the immune system. During the last 2 decades, stem cell therapy has been increasingly considered as a therapeutic option in various diseases, including Parkinson's disease, Alzheimer's disease, stroke, spinal cord injury, multiple sclerosis, inflammatory bowel disease, liver disease, diabetes, heart disease, bone disease, renal disease, respiratory disease and haematological abnormalities such as anaemia. This is due to the unique properties of stem cells that both divide and differentiate to the specialized cells in the damaged tissue. Moreover, they impose immunomodulatory properties affecting the diseases caused by immunological abnormalities such as SSc. In the present review, the efficacy of stem cell therapy with two main types of stem cells, including mesenchymal stem cells and hematopoietic stem cells, will be reviewed. Moreover, other related issues, including safety, changes in immunological parameters, suitable choice of stem cell origin, conditioning regimen and complications of stem cell treatment will be discussed. What does this mean for patients?SSc is a disease that causes abnormal collagen production in the skin and internal organs. This results in thickening of these tissues as well as problems with blood vessels. SSc has two main forms: limited and diffuse. These types can be distinguished by how much skin is affected, which internal organs are affected and the patient's autoantibody profile (measured using a blood test). There are few treatment options and a high mortality rate in SSc, making it difficult to deal with this disease. During the last 2 decades, stem cell therapy has become an option for treating various diseases. After it divides, a stem cell generates a new stem cell, which can then differentiate into a specialized cell (e.g. a muscle cell). It has also been shown that treatment with stem cells is safe for patients. There are several types of stem cells, including mesenchymal stem cells (MSCs) and haematopoietic stem cells (HSCs). Both MSCs and HSCs can improve disease activity and severity in people with SSc. They both result in an improvement in the signs and symptoms of disease.