Why Mesenchymal Stem Cells?

Mesenchymal stem cells, also known as MSCs, have become the preferred option for many patients due to their properties, which include differentiation, regenerative potential, immune modulation, and inflammation reduction.

In the past, mesenchymal stem cells were used to treat medical conditions for tissue repair and only in regenerative medicine. Now, with their evolving immune-modulating mechanisms, many clinics and hospitals use them to treat immune disorders. These unique cells are a valuable resource for many clinics and hospitals due to their distinctive characteristics. Numerous clinical trials and researchers have noted their ability to treat various conditions such as heart disease, graft-versus-host disease (GVHD), and autoimmune disorders.

About Mesenchymal Stem Cells

Mesenchymal stem cells (MSCs) are specialized cells derived from various parts of the body, such as bone marrow, adipose tissue, and umbilical cord tissue. These cells are uniquely capable of differentiating into different types of cells, acting like multi-talented artists in the body’s cell community.

These cells can self-renew and transform into many types of cells. They can be easily transplanted into someone’s body due to their low rejection rate, causing minimal disturbance to the immune system.

Scientists are excited about mesenchymal stem cells because they may help treat many health issues and even assist in building new tissues.

Understanding the Term “Mesenchymal”

Mesenchymal tissue is a type of tissue found in embryos and adults. It is also referred to as a type of embryonic connective tissue originating from the mesodermal germ layer during development. The mesoderm plays a vital role in the formation of connective tissues, blood vessels, lymphatic vessels, and various organs like bones and muscles.

Mesenchymal stem cells can differentiate into various types of cells, such as osteocytes, chondrocytes, myocytes, and adipocytes. These cells are the ideal medical term for tissue repair, wound healing, and organ growth.

How to Identify Human Mesenchymal Stem Cells?

There are some minimum criteria that define whether cells are human mesenchymal stem cells. These criteria are suggested by the Mesenchymal and Tissue Stem Cell Committee of the International Society for Cellular Therapy. The criteria are:

Mesenchymal stem cells adhere to plastic surfaces in standard culture conditions.
Certain proteins such as CD73, CD90, and CD105 are present on the surface of human multipotent stem cells. These cells lack markers like CD45, CD34, CD14, and CD19, which are found on blood cells.
If the cell can divide and differentiate into osteocytes, adipocytes, and chondrocytes, it qualifies as a human mesenchymal stem cell.

As our knowledge grows, we’re seeing changes in the ways we identify mesenchymal stem cells. However, following the guidelines of the International Society for Cellular Therapy helps standardize how we describe them, making it easier for scientists to collaborate in mesenchymal stem cell research.

Recently, research on mesenchymal stem cells (MSCs) has been delayed due to differences in isolation, cultivation, and understanding. This makes it difficult to compare various studies and their outcomes.

Mesenchymal Stem Cells’ Differentiation Abilities

Mesenchymal stem cells are specialized cells with the ability to differentiate into various types of cells, including osteogenic, chondrogenic, and adipogenic cells. They can also differentiate into other human cell types such as myocytes, neurons, and stromal cells.

Let’s take a look at other types of cells that mesenchymal stem cells can differentiate into to treat various medical conditions. This was reported in Stem Cell Reviews and Reports based on a study. These cells include:

Osteocytes (bone cells)
Chondrocytes
Adipocytes
Myocytes
Neurons
Hepatocytes
Pancreatic cells
Cardiomyocytes
Endothelial cells (blood vessel cells)
Epithelial cells (cells lining surfaces)

Whenever our body needs help repairing injury, these cells come to the rescue. They reach the damaged area and begin transforming into specific types of cells necessary for healing.

One thing to keep in mind is that mesenchymal stem cells’ differentiation ability may depend on various factors such as the source of the stem cells, how they’re cultured, and their environmental conditions.

What is Differentiation Potential?

Differentiation potential is a medical term referring to a cell’s ability to develop into different types of cells. This requires a transition from proliferation to specialization. It’s a crucial concept with the potential to treat a wide range of medical conditions.

For example, if someone has heart damage, doctors use stem cells and differentiate them into specialized cells needed for heart healing. These replace damaged cells with new ones and improve health.

Two main factors govern cell differentiation: genetic and epigenetic. Genetically, gene activity can be regulated by proteins and chemical signals. Epigenetically, it involves adding or removing chemical groups from DNA, modifying how surrounding proteins function, and altering how specific RNA types are used.

The differentiation process involves several stages:

Specific genes in the cell’s DNA are activated. This tells the cell which proteins to produce.
The cell begins to grow and replicate more of its kind.
Finally, cells develop and mature, ready to perform their functions.

What Factors Affect the Differentiation Process?

A cell’s ability to transform into various types (differentiation) can be influenced by:

Genetics: Our genes carry instructions determining what cell type we can become.
Environmental factors: Elements like temperature, chemicals, and nutrients around us affect cell development.
Signaling molecules: These can instruct a cell to become a muscle cell, a nerve cell, or another type.
Neighboring cells: Cells communicate, and this interaction helps guide their growth.

Mesenchymal stem cells’ ability to transform into specific cells may also depend on where the cells are from, the person’s age, the stem cell source, and culture conditions.

Functions of Mesenchymal Stem Cells

Mesenchymal stem cells have proven useful in treating many medical conditions. Patients often experience remarkable outcomes after using these innovative cells. Understanding their functions enhances our knowledge of them. Key functions include:

Tissue repair and regeneration: MSCs are essential for repairing and regenerating tissues. They can differentiate into bone, cartilage, fat cells, and more—crucial for healing damaged tissue.
Immune modulation: These cells can regulate immune system activity. They suppress immune cells such as T-cells, B-cells, and natural killer cells, reducing inflammation and preventing immune attacks on healthy tissues.
Anti-inflammatory effects: MSCs secrete anti-inflammatory molecules that reduce body inflammation. Through factors like IL-10 and TGF-β, they ease inflammatory responses and promote tissue healing.
Angiogenesis (blood vessel formation): MSCs promote new blood vessel formation—critical for delivering nutrients and oxygen to tissues and aiding their regeneration.
Supporting other cell types: MSCs help other cells survive and function by releasing growth factors and cytokines, creating a supportive environment for repair and regeneration.

Where Can Mesenchymal Stem Cells Be Sourced?

Using mesenchymal stem cells to treat various medical conditions is considered a better option than traditional therapies. These cells can be found in multiple body parts:

Bone marrow: MSCs are commonly found in bone marrow, a spongy tissue inside bones that holds immature cells. “Bone marrow aspiration” is the procedure used to collect them—safe and simple.
Adipose tissue (fat): This body tissue contains fat. Researchers extract MSCs from it using a method called liposuction, involving a hollow stainless steel tube to remove fat.
Umbilical cord tissue: This human tissue connects the fetus to the placenta. Doctors collect MSCs from it at birth for future use.
Peripheral blood: MSCs from peripheral blood offer a less invasive option for cell isolation. These circulating cells show promise in cardiovascular repair and immune modulation.
Placental tissues: The placenta is a valuable MSC source obtained post-delivery without harming mother or baby. These cells are effective for treating autoimmune diseases and inflammatory conditions.
Synovial fluid: Found in joints, this fluid contains regenerative stem cells. Isolating MSCs from it offers a novel way to treat musculoskeletal diseases like osteoarthritis and cartilage defects.
Dental pulp: Dental pulp stem cells (DPSCs) come from tooth pulp during routine dental procedures. They hold promise for dental, facial, and nerve tissue regeneration.

It’s essential to note that isolating and expanding MSCs from different sources may yield cells with varied properties. Also, isolating them from peripheral blood and synovial fluid is harder and less efficient. MSCs are particularly effective when sourced from bone marrow, adipose tissue, or umbilical cord.

Limitations of Mesenchymal Stem Cells

Despite their many benefits in treating medical conditions, MSCs also have limitations. Below are a few key points:

MSCs sourced from different tissues and donors may behave differently, affecting treatment consistency and efficacy.
Continuous isolation and cultivation in labs can be difficult, leading to variability and unexpected outcomes.
MSCs can differentiate into certain cells like bone or cartilage but are more limited than other stem cell types.
Ensuring MSC quality and purity is challenging; contaminants can compromise their safety and therapeutic effectiveness.
Although promising, the long-term safety and efficacy of MSC-based therapies are not fully understood. More research is needed to clarify their clinical outcomes.

Differences Between Mesenchymal and Hematopoietic Stem Cells

Mesenchymal stem cells (MSCs) and hematopoietic stem cells (HSCs) are both adult stem cells but differ in the following ways:

Differentiation potential:
- MSCs: Can differentiate into bone, cartilage, fat, and other cell types.
- HSCs: Primarily differentiate into blood and immune cells—like red and white blood cells and platelets.
Source:
- MSCs: Found in various body parts like bone marrow, adipose tissue, umbilical cord, peripheral blood, and placenta.
- HSCs: Collected mainly from bone marrow and, in smaller amounts, from peripheral blood.
Immunological properties:
- MSCs: Can modulate immune system function and reduce inflammation.
- HSCs: Produce and maintain immune cells but don’t have the same immune-modulating capability.
Therapeutic uses:
- MSCs: Being studied for tissue repair, regenerative medicine, and cell-based therapies for various diseases.
- HSCs: Used to treat blood disorders like leukemia, lymphoma, and sickle cell anemia, and in bone marrow transplants.

Note: Both cell types are still undergoing extensive clinical trials to understand their therapeutic roles better.

What Medical Conditions Can Be Treated with Mesenchymal Stem Cells?

MSCs have become a go-to option for treating numerous medical conditions due to their impressive results. Some conditions that benefit include:

Osteoarthritis: A joint disease that worsens without care. MSCs can now treat it by promoting cartilage repair and reducing inflammation.
Rheumatoid arthritis: Mesenchymal stem cells have anti-inflammatory and immunomodulatory properties that could be useful in treating rheumatoid arthritis.
Graft-versus-host disease: This condition can be seen after a bone marrow transplant, but it can be treated with the immunosuppressive properties of mesenchymal stem cells.
Myocardial infarction: Researchers are investigating whether mesenchymal stem cells could be an ideal weapon against heart attacks by repairing heart tissue.
Spinal cord injury: Mesenchymal stem cells have been studied for their ability to help restore injured nerve tissue and spinal cord injuries.
Autoimmune diseases: Due to their anti-inflammatory and immunomodulatory properties, mesenchymal stem cells may be useful in treating autoimmune diseases, including lupus and multiple sclerosis.
Type 1 diabetes: Researchers have investigated whether mesenchymal stem cells can help type 1 diabetics maintain their insulin-producing cells.
Lung diseases: Mesenchymal stem cells are known for their ability to restore lung tissue, which is beneficial for conditions such as chronic obstructive pulmonary disease (COPD) and acute respiratory distress syndrome (ARDS).
Multiple sclerosis: This disease can affect the body’s central nervous system, which can be dangerous. However, pluripotent stem cells have anti-inflammatory and immunomodulatory properties, making them effective in treating this condition.
Lyme disease: Mesenchymal stem cells have the ability to reduce inflammation and improve the recovery of damaged tissue caused by the Lyme disease bacteria.
Parkinson’s disease: Parkinson’s disease is a degenerative condition that impairs movement. Mesenchymal stem cells (MSCs) have been studied for their potential to protect and repair brain neurons destroyed in this condition.
Amyotrophic lateral sclerosis (ALS): Mesenchymal stem cells can differentiate into different cell types, such as neurons, to repair damaged cells in the spinal cord.

Notes: It is important to note that further studies are needed to understand the full potential of mesenchymal stem cells (MSCs) to make them safe and effective treatments. Furthermore, mesenchymal stem cell therapy is still under investigation. In the late 19th century, the medical community was aware of the existence of mesenchymal stem cells. Thanks to recent discoveries, doctors can now enhance and stimulate these cells to treat a variety of diseases.

Why Mesenchymal Stem Cells?