Introduction
Stem cells originate from the embryo and differentiate into specialized cells that develop to become tissues during the process of organogenesis which also has the ability to continuously replenish themselves. Stem cells are classified into adult stem cells and embryonic stem cells. Pluripotent stem cells are adult stem cells that have undergone genetic reprogramming to become embryonic-like pluripotent stem cells. Adult stem cells are constantly present in the body and are used for tissue regeneration or apoptosis. There are five types of adult stem cells namely, hematopoietic stem cells (HSC) (which produce blood and immune cells), mesenchymal stem cells (which can differentiate into bone cells, cartilage cells, muscle cells, and fat cells), neural stem cells, epithelial stem cells, and skin stem cells.
Chronic pathologies known as autoimmune diseases are caused by a lack of immunological tolerance to self-antigens, which can harm the entire body or just a particular organ. Autoimmune rheumatic disease (AIRD) manifestations are diverse due to the interaction of the etiology with genetic risk factors, racial disparities, and infection-induced oligoclonal lymphocyte responses. The enduring persistence of tissue autoantigens, frequently not eliminated, sustains autoimmune reactions. It is evident that the acceptability of treatment techniques, such as hematopoietic stem cell transplantation (HSCT), which resets the host immune system, is on the rise and is due to a better understanding of the mechanisms involved in immunopathogenesis and of effector cells.
What Are Rheumatic Diseases?
In many autoimmune rheumatic diseases (ARDs), innate and adaptive immune responses result in autoimmune-mediated tissue damage. In addition to arthritis and other problems that affect the joints, tendons, muscles, ligaments, bones, and muscles, rheumatic disease is a general or umbrella term for these conditions. Rheumatoid arthritis, generally known as RA, and osteoarthritis are the two most common rheumatic diseases. Multiple joints may be swollen, painful, and inflamed. Gout, fibromyalgia, and lupus are a few other frequent rheumatic diseases.
Numerous rheumatic disease subtypes can be identified early by rheumatologists (doctors with specialized training in treating rheumatic disorders such as arthritis is known as a rheumatologist). These include musculoskeletal pain, rheumatoid arthritis, other autoimmune illnesses, osteoporosis, and anomalies of the musculoskeletal system. There are several different types of pharmacological therapy, including oral analgesics (painkillers), nonsteroidal anti-inflammatory drugs (NSAIDs), corticosteroids, disease-modifying anti-rheumatic drugs (DMARDs), biologics, and Janus kinase inhibitors. Other treatment approaches include physical therapy, occupational therapy, and specific exercise programs to improve joint flexibility and muscle strength, therapy using heat and cold, splints, braces, relaxation therapy, and surgery (especially for arthritis).
What Is Hematopoietic Stem Cell Transplantation?
Patients with dysfunctioning or depleted bone marrow can receive healthy hematopoietic stem cells through a procedure known as a hematopoietic stem cell transplant (HSCT) or bone marrow transplant. This treatment is most commonly used to treat both malignant and non-malignant diseases and has many advantages. The function of the bone marrow is improved as a result. Additionally, depending on the disease being treated, it can permit the eradication of cancerous tumor cells. Moreover, it can produce healthy cells to replace unhealthy ones in conditions including immune deficiency syndromes and hemoglobinopathies. The main advantage of HSCT for autoimmune diseases is the potential to create an "immune reset," or the ability to get rid of the autoimmune T cell clones and change the course of the disease. However, the additional toxicity of the high-dose chemotherapy or radiation employed as part of the conditioning regimen is one of the main drawbacks of HSCT for autoimmune diseases.
How Does Hematopoietic Stem Cell Transplantation Help With Rheumatic Diseases?
The Benefits:
Hematopoietic stem cells have made tremendous progress in treating autoimmune rheumatic diseases as well. It is now understood to be a practical treatment option for severe autoimmune diseases, especially systemic sclerosis.
While treating autoimmune rheumatic diseases, several factors, including the type and stage of the autoimmune disease, the kind of transplant, and the conditioning regimen, determine lasting clinical remissions or even cures.
Due to the development of inflammatory reactions, which erodes the synovial cartilage and surrounding bone, RA is characterized by progressive joint deterioration. As the disease advances, extra-articular signs such as lung fibrosis, vasculitis, and ocular disease may appear, as well as articular symptoms like pain and morning stiffness. With the introduction of biologics and early aggressive DMARD therapy, early disease has been controlled adequately with a chance of remission. Some patients are resistant to therapy despite aggressive techniques. In cases of severe, resistant RA, autologous HSCT is a relatively safe method of salvage therapy.
The Success Rate:
The immunomodulating impact of HSCT was supported by a more significant response to biologic and nonbiologic DMARDs after the procedure. Additionally, the studies for RA have shown that overall survival rates have been around 98%. HSCT has had the best results for patients with systemic sclerosis and systemic lupus erythematosus; however, for RA, it was linked to a higher rate of relapses. A study reported that most kids who underwent autologous and/or allogeneic hematopoietic stem cell transplantation for severe pediatric rheumatic and autoinflammatory diseases experienced long-term remission. However, there is still a sizable rate of transplant-related morbidity, mortality, and disease relapse.
Precautions:
The main determinants favoring successful results are careful patient and donor selection, timing the transplant earlier in the course of the disease rather than as a "last resort," and selecting the best appropriate conditioning regimen for each patient. The patients, their families, and the relevant medical teams must work closely together.
It's crucial to remember that HSCT for rheumatic disorders is currently regarded as an experimental therapy and is not yet generally accessible. Infection, organ damage, and graft-versus-host disease in the case of allogeneic transplantation are dangers that come with the procedure. Patient selection and constant monitoring are essential to guarantee the safety and efficacy of HSCT.
More studies and larger-scale clinical studies are required to understand further the ideal patient selection criteria, scheduling, conditioning regimens, and long-term outcomes related to HSCT in rheumatic illnesses. Targeted treatments, immunomodulatory drugs, and other measures to fine-tune and personalize the process may help increase its efficacy while lowering the risk of consequences.
Conclusion
According to recent research, rheumatic disorders may be treated with hematopoietic stem cell transplantation (HSCT). Despite being generally utilized for hematological malignancies, HSCT has shown promise in giving long-term remission and disease modification for a few rheumatic diseases, including systemic sclerosis and multiple sclerosis. Hematopoietic stem cells are transplanted, either from the patient's cells (autologous HSCT) or from a donor who is a match (allogeneic HSCT), and then the immune system is rebuilt. Finally, hematopoietic stem cell transplantation shows potential as a treatment for several rheumatic conditions. Although it is full potential and ideal application has yet to be established, continued research and breakthroughs in the field give people living with these complex disorders hope for better outcomes and a higher quality of life.
