Mesenchymal stem cells have recently been gaining popularity for treating rheumatoid arthritis, and are currently the subject of several clinical trials. The search for more effective therapies has been fueled by the limitations of current treatments for rheumatoid arthritis. Preliminary results suggest that mesenchymal stem cells are a promising new avenue for improving patient’s pain, inflammation and overall quality of life.
Rheumatoid arthritis is an autoimmune disorder, a condition in which the body’s own immune system mistakenly attacks healthy cells. The immune response seen in patients with rheumatoid arthritis results in inflammation and swelling of the joints, ultimately causing destruction of the cartilage and fusion of the bone. The joints most commonly affected are in the hands, feet and cervical spine. An understanding of the complex immune pathways that result in joint inflammation has provided a basis for targeted therapies that reduce the inflammatory response. The greatest limitations of current therapies include; patient intolerance, toxicity, risk of infections and, in some cases, only a partial response with continued joint pain and damage. Owing to these limitations, new therapeutic strategies are needed.
Mesenchymal stem cells are immature cells that can divide and become a number of different specialized cells in the body including fat, bone and cartilage cells. Importantly, and making them somewhat ideal for application in the treatment of immune-related diseases such as rheumatoid arthritis, mesenchymal stem cells have recently demonstrated anti-inflammatory and immunosuppressive effects.
In a recent trial, the safety of mesenchymal stem cells in the treatment of rheumatoid arthritis was tested. Specifically, umbilical cord-derived stem cells were used, as they are more easily accessible and have a greater capacity to proliferate. The results of this preliminary study were promising, showing an overall reduction in patients’ joint pain, swelling and stiffness. The effects were seen as soon as twelve hours after treatment and lasted for up to three months. The suggested reason for the beneficial response in patients was a reduction in pro-inflammatory factors in the blood. Moreover, a subset of immune cells called T cells, which play an important role in suppressing autoimmune responses, were found to be increased in the peripheral blood of treated patients.
More clinical studies are currently underway to assess the safety and effectiveness of mesenchymal stem cells in the treatment of rheumatoid arthritis. In these trials, patients will be treated with intravenous infusions of stem cells at varying intervals. While the primary measure of these studies is the safety for use in patients, other outcome measures being assessed include markers of disease progression, patient quality of life measures, and pain scores. While two studies are evaluating the use of mesenchymal stem cells alone, an alternate study will also assess the effect of mesenchymal stem cells administered in combination with conventional therapy for rheumatoid arthritis.
The preceding scientific research and the emerging clinical results suggest that mesenchymal stem cells may be a new hope for patients suffering with rheumatoid arthritis. In addition to the demonstrated anti-inflammatory properties of these cells, they may also be a source of growth factors. It has therefore been suggested that they could even play a role in protecting the affected tissue from further injury or damage in addition to boosting tissue repair. More studies are needed to determine the exact mechanisms of action and the resultant benefits to patients suffering from rheumatoid arthritis.
American Medical Association – Basics of Stem Cell Research. Available from: http://www.ama-assn.org//ama/pub/physician-resources/medical-science/genetics-molecular-medicine/related-policy-topics/stem-cell-research/basics-stem-cell-research.page Last Accessed: Nov 20, 2013.
Wang L, Wang L, Cong X, Liu G, Zhou J, Bai B, Li Y, Bai W, Li M, Ji H, Zhu D, Wu M, Liu Y. Human Umbilical Cord Mesenchymal Stem Cell Therapy for Patients with Rheumatoid Arthrits: Safety and Efficacy. Stem Cells and Development. 22(24):DOI:10.1089/scd.2013.0023.
Uccelli A, Moretta L, Pistoia V. Mesenchymal Stem Cells in Health and Disease. Nature Reviews Immunology, 8, 726-736 Sept 2008.
Burt RK, Loh Y, Pearce W, Beohar N, Barr WG, Craig R, Wen Y, Rapp JA, Kessler J. Clinical Applications of Blood-Derived and Marrow-Derived Stem Cells for Non-Malignant Diseases. JAMA, 299(8): 925-936, Feb 2008.
ClinicalTrials.gov “Safety and Efficacy Study of Umbilical Cord-Derived Mesenchymal Stem Cells for Rheumatoid Arthritis” Available from: http://clinicaltrials.gov/ct2/show/NCT01547091?term=NCT+01547091&rank=1 Last Accessed: Nov 20, 2013.
ClinicalTrials.gov “Umbilical Cord Tissue-Derived Mesenchymal Stem Cells for Rheumatoid Arthritis” Available from: http://clinicaltrials.gov/ct2/show/NCT01985464?term=NCT01985464&rank=1 Last Accessed: Nov 20, 2013
ClinicalTrials.gov “A Multi-Center Study a Single IV Infusion of Allogenic MPCs in Patients with Rheumatoid Arthritis and Incomplete Response to at Least one TNF Alpha Inhibitor” Available from: http://clinicaltrials.gov/ct2/show/NCT01851070?term=NCT01851070&rank=1 Last Accessed: Nov 20, 2013
Written by Deborah Tallarigo, PhD