Tehran University Medical Journal

An increase in the average age of the population and physical activities where the musculoskeletal system is involved as well as large number of people suffering from skeletal injuries which impose high costs on the society. Bone grafting is currently a standard clinical approach to treat or replace lost tissues. Autografts are the most common grafts, but they can lead to complications such as pain, infection, scarring and donor site morbidity. The alternative is allografts, but they also carry the risk of carrying infectious agents or immune rejection. Therefore, surgeons and researchers are looking for new therapeutic methods to improve bone tissue repair. The field of tissue engineering and the use of stem cells as an ideal cell source have emerged as a promising approach in recent years. Three main components in the field of tissue engineering include proper scaffolds, cells and growth factors that their combination leads to formation of tissue-engineered constructs, resulting in tissue repair and regeneration. The use of scaffolds with suitable properties could effectively improve the tissue function or even regenerate the damaged tissue. The main idea of tissue engineering is to design and fabricate an appropriate scaffold which can support cell attachment, proliferation, migration and differentiation to relevant tissue. Scaffold gives the tissue its structural and mechanical properties, for instance flexibility and stiffness that is related with the tissue functions. Biomaterials used to fabricate scaffolds can be categorized into natural or synthetic biodegradable or non-biodegradable materials. Polymers are the most widely used materials in tissue engineering. Growth factors are a group of proteins that cause cell proliferation and differentiation. Two main cell sources are specialized cells of desired tissue and stem cells. However, according to the low proliferation and limited accessibility to the cells of desired tissue, stem cells are better suggestion. Combination of mesenchymal stem cells harvested from bone marrow, adipose tissue and cord blood with proper scaffolds and growth factors could be a useful method in treatment of skeletal injuries. In this review paper, we focus on the application of mesenchymal stem cells in the repair of damaged bone, cartilage, meniscus, ligaments, tendons and spine tissue.

Primary Immune Deficiencies are a group of heterogeneous disorders that involve the innate or acquired immune system, or a combination of them. The underlying disorder may be related to decreased levels or function, or a complete lack of one or more components of the immune system in general. These diseases can occur with a prevalence of about 1 in 10000 live births. According to the fourth update on the Iranian national registry of Primary Immune Deficiency in October 2018, the total number of registered PIDs in Iran are 3056 patients. However, it is supposed to be more prevalent and it seems increasing awareness shall reveal many new cases, especially in societies with prevalent consanguineous marriages like Iran. These disorders predispose patients to recurrent infections, autoimmunity and malignancy and can cause a huge burden on health care systems. This group of diseases has a wide range of symptoms, which quick recognition and timely treatment of them, can greatly reduce the complications of the disease. These symptoms may include recurrent or severe infections, failure to thrive, autoimmune disorders, as well as articular-skeletal manifestations. A variety of skeletal manifestations are seen in patients with primary immunodeficiency, among which septic arthritis caused by pyogenic bacteria or mycoplasma arthritis is the most common joint-bone manifestation. Joint and skeletal involvement is less commonly seen as a sign of primary immune defects. This issue is importance in reducing the cost of diseases and improving the patients’ quality of life. Our review attempted to introduce the most common manifestations of bone and joint in patients with primary immunodeficiency and available treatments for these manifestations. Because of the wide range of symptoms in these patients, it is recommended to observe the rare and suspicious manifestations in the patients with any atypical bone and joint presentations such as: recurrent septic arthritis, infection with unusual germs, immunodeficiency in their relatives, and any history of well-known red flags of PIDs. The Rheumatologist should consider these manifestations and think about the possibility of deficiency disorder.