Last Updated on December 1, 2025 by Bilal Hasdemir

Recent studies have shown a growing worry about the side effects of stem cell therapy. Many patients have had bad reactions.

The use of mesenchymal stem cells in treatments is increasing. It’s important to know the risks of this treatment.

Stem cells have shown promising results in therapy. But, it’s key to know the possible side effects for safe treatment.

Key Takeaways

• Stem cell therapy can result in various side effects, ranging from mild to severe.
• Understanding the possible risks is key for safe treatment.
• Research is ongoing to lessen the bad effects of stem cell therapy.
• Patients should be informed of potential side effects prior to undergoing treatment.
• The use of stem cells in therapy is growing, with more studies.

Understanding Mesenchymal Stem Cells and Their Applications

Mesenchymal stem cells are being studied for their role in healing and growing new tissue. They can turn into different cell types, like bone and fat cells. This makes them useful for many medical uses.

Definition and Sources of Mesenchymal Stem Cells

Mesenchymal stem cells (MSCs) are special cells that can come from places like bone marrow, adipose tissue, and umbilical cord. They can grow into many cell types and keep growing themselves. MSCs are known by markers like CD73, CD90, and CD105.

MSCs can come from many places, making it easier to find them for treatments. Bone marrow-derived MSCs are well-studied, but adipose tissue-derived MSCs are also popular because they’re easy to get.

Common Medical Applications

MSCs are used in many medical areas because of their healing and immune system balancing abilities. They’re being looked at for treating cardiovascular diseases, autoimmune disorders, and musculoskeletal injuries. They’re also being studied for helping with organ transplantation and tissue engineering.

There are many ways MSCs can help in medicine, and research is always finding new uses. As we learn more about MSCs, we can develop new treatments for many health issues.

Common Immediate Side Effects After Treatment

MSC therapy is promising but can cause immediate side effects. These side effects are watched closely by healthcare providers. They aim to keep patients safe and comfortable.

Injection Site Reactions

One common side effect is reactions at the injection site. Symptoms include pain, swelling, redness, and itching. These symptoms are usually mild and go away in a few days.

• Pain at the injection site is often treated with over-the-counter pain relievers.
• Swelling and redness are usually temporary and may feel warm at the site.

Fever and Fatigue

Patients may also experience fever and fatigue after MSC therapy. Fever is usually mild and short-lived. Fatigue can vary in how severe it is.

“Some patients experience flu-like symptoms, including fever and fatigue, after MSC infusion, which generally resolve within a few days.”

To deal with these side effects, patients are told to drink plenty of water and rest. Sometimes, medication is given to help with symptoms.

1. Keep an eye on body temperature and tell healthcare providers about any high fevers.
2. Do light physical activities as you can to help reduce fatigue.

Short-Term Systemic Side Effects

MSCs can cause short-term side effects like pain and digestive issues. These effects are usually short-lived but can affect how well you feel during recovery.

Pain and Discomfort Beyond Injection Site

Some people might feel pain or discomfort in places other than where they got the MSCs. This happens because MSCs spread throughout the body. It can cause temporary inflammation or irritation.

Managing pain effectively is key to keeping patients comfortable. Doctors might suggest pain meds or physical therapy to help with discomfort.

Constipation and Digestive Issues

After MSC therapy, some people might face constipation and digestive issues. These problems can come from how the body reacts to MSCs or from treatment meds.

To lessen these issues, eating a balanced diet rich in fiber and drinking plenty of water is recommended. Doctors might also prescribe meds for constipation or other digestive problems.

It’s important to watch and manage these short-term side effects for MSC treatment to work well. Knowing what causes them and how to deal with them helps patients get through the recovery better.

Cardiovascular Complications of Mesenchymal Stem Cells

cardiovascular complications

MSC therapy is promising but comes with risks. It can cause arrhythmias and blood pressure changes. The heart is complex, and MSCs might affect how it works.

Arrhythmia and Heart Palpitations

Some patients get arrhythmias from MSC therapy. Heart palpitations are a sign of this. They can be scary and show heart problems.

We don’t know all about MSCs and heart issues. But, MSCs might mess with the heart’s electrical system. More study is needed to understand and fix this problem.

Blood Pressure Fluctuations

Blood pressure can change in MSC therapy patients. This can be a big deal, even for those with heart problems.

The table below shows some heart problems linked to MSC therapy:

Cardiovascular Complication	Potential Causes	Clinical Implications
Arrhythmia	Interaction with heart’s electrical system	Increased risk of cardiovascular events
Blood Pressure Fluctuations	Effects on vascular tone and cardiac output	Risk of hypertensive or hypotensive episodes

It’s key to know about MSC therapy’s heart risks. This helps make it safer and more effective. Research is ongoing to learn more about its benefits and risks.

Infection Risks and Inflammatory Responses

Infection risks and inflammatory responses are key when looking at MSC therapy safety. Any invasive medical treatment, like MSCs in the body, can cause problems.

Bacterial Infection Concerns

Bacterial infections might happen if MSCs are contaminated during processing. Strict aseptic techniques and careful donor screening are vital to lower this risk. Research shows that quality control can greatly reduce bacterial contamination risks.

“The risk of bacterial infection associated with MSC therapy can be mitigated through careful handling and processing of MSCs.”

Expert Opinion on MSC Safety

Viral Transmission Possibilities

Viral transmission is another worry with MSC therapy. Though rare, viruses like HIV, hepatitis B, and C can be passed on if the donor is infected. Comprehensive donor screening is key to avoiding such transmissions.

Risk Factor	Prevention Measure
Bacterial Infection	Aseptic techniques, donor screening
Viral Transmission	Comprehensive donor screening, viral testing

To lessen infection and inflammatory response risks, strict protocols for MSC preparation and use are essential. This means using sterile equipment and following proper handling procedures.

Tissue-Specific Side Effects

Tissue-specific side effects are a big worry with mesenchymal stem cell therapy. MSCs are being studied for their healing powers. It’s key to know how they affect different tissues to make treatments safe and work well.

Fibrosis Development

Fibrosis is when too much fibrous tissue forms. It can scar organs and tissues, making them not work right. Studies show MSCs might cause fibrosis in some cases. This means we need to watch closely and find ways to prevent it.

The reasons for fibrosis with MSC therapy are complex. Things like where MSCs come from, how they’re given, and which tissue they target matter. Knowing these details helps us create treatments that lower fibrosis risk.

Localized Tissue Reactions

Localized tissue reactions are another side effect of MSC therapy. These can be inflammation, swelling, or other bad reactions where MSCs are given. How bad these reactions are can vary a lot. It depends on things like how many MSCs are used and how the person’s body reacts.

To deal with these reactions, we need to understand what causes them. We might need to change how MSCs are given or use medicines to help. Watching patients closely is key to spotting and fixing these reactions fast.

In summary, side effects like fibrosis and tissue reactions are big concerns with MSC therapy. By learning about these issues and their causes, doctors can manage risks better. This helps make MSC therapy safer and more effective.

Serious Vascular Complications

Patients getting MSC therapy might face serious vascular issues like thromboembolism and microvascular obstruction. These problems can really affect how well a patient does and need careful handling.

Thromboembolism Risk

Thromboembolism is a big risk with MSC therapy. It’s when a blood clot forms inside a blood vessel. This can block blood flow to important organs.

Risk Factors for Thromboembolism:

• Pre-existing cardiovascular disease
• History of thrombotic events
• High-dose MSC administration

Microvascular Obstruction

Microvascular obstruction is when small blood vessels get blocked. This can cause tissue ischemia and organ dysfunction. MSCs might cause this because of their size and how they can clump together.

Complication	Description	Risk Factors
Thromboembolism	Formation of a blood clot within a blood vessel	Pre-existing cardiovascular disease, history of thrombotic events
Microvascular Obstruction	Blockage of small blood vessels	High-dose MSC administration, MSC aggregation

It’s key to know about these serious vascular problems when using MSC therapy. Doctors need to be aware of the risks. They should take steps to prevent these issues.

Genetic and Oncological Concerns

chromosomal abnormalities

As MSC therapy grows, knowing its genetic and cancer risks is key. MSCs might cause genetic problems and cancer issues. This is a big topic in research and debate.

Chromosomal Abnormalities

MSC therapy raises concerns about chromosomal problems. Studies show MSCs can change genetically in in vitro culture. This might lead to unstable chromosomes and abnormal cell growth.

Here are important points about chromosomal issues with MSCs:

• Genetic changes during culture growth
• Risk of aneuploidy and its effects
• Impact on MSC safety and function

Tumorigenesis Potencial

MSCs might also lead to cancer growth. They can help tumors grow and spread. This is due to their ability to suppress the immune system and release factors that help tumors.

Important factors in MSCs’ cancer risk include:

1. The type of MSCs used
2. How MSCs are prepared and given
3. The immune health of the person receiving them

Knowing these factors helps us understand MSC therapy’s cancer risks. It also helps us find ways to lower these risks.

Immune System Responses to Mesenchymal Stem Cells

Mesenchymal stem cell therapy starts a complex immune response. It includes both calming down the immune system and making it react. The immune system’s response to MSCs involves many cell types and pathways.

When MSCs enter the body, they can change the immune response in different ways. This can lead to good effects or bad ones. It’s important to understand these responses to use MSC therapy safely and effectively.

Allergic and Hypersensitivity Reactions

Even though MSCs are mostly safe, they can cause allergic and hypersensitivity reactions in some people. These reactions can be mild or very serious. They can happen at the injection site or affect the whole body.

• Local reactions may include redness, swelling, and pain at the site of MSC administration.
• Systemic reactions can manifest as fever, chills, or even anaphylaxis in rare cases.

It’s important to watch for signs of allergic or hypersensitivity reactions, mainly at the start of MSC therapy.

Immunomodulatory Effects

One of the main benefits of MSCs is their immunomodulatory effects. They help control the immune system’s response. This can help treat many immune-related diseases.

MSCs can change the immune response in several ways. They can:

1. Slow down T-cell growth and activity.
2. Help more regulatory T cells grow.
3. Release anti-inflammatory cytokines.

Finding the right balance between MSCs’ good effects and possible immune reactions is key. Researchers are working hard to improve this balance. They want to make MSC-based therapies better and safer.

Donor-Related Complications

donor-related complications 

Mesenchymal stem cell donation is key in stem cell therapy. It comes with risks for donors, like reactions during collection and compatibility issues. These factors are important to consider.

Donor Reaction During Collection

The process of getting MSCs from bone marrow or fat can cause adverse reactions in donors. These can be mild or serious, like infections or nerve damage. For example, getting MSCs from bone marrow can lead to pain, bruising, and tiredness.

“The risk of complications during MSC donation should not be underestimated,” experts say. Careful donor selection and management are critical to reduce these risks. Donors need to be checked for health issues that could raise the risk of problems.

Donor-Recipient Compatibility Issues

Matching the donor and recipient is vital in MSC therapy. Incompatibility can cause immune reactions against the MSCs. This can make the treatment less effective or cause side effects. HLA typing is used to check if the donor and recipient are compatible, but MSCs are generally not very immunogenic.

A study found that

“the degree of HLA mismatch can influence the outcome of MSC transplantation, with a higher degree of mismatch potentially leading to a greater risk of immune-related complications.”

So, making sure the donor and recipient are compatible is key for MSC therapy success.

In summary, MSC donation is important in stem cell therapy but comes with risks. It’s important to understand and manage these risks to make MSC therapy safe and effective.

Risk Factors That Increase Side Effect Probability

Several factors can raise the chance of side effects from MSC therapy. It’s important for both patients and doctors to know these factors. This knowledge helps in making smart treatment choices.

Pre-existing Medical Conditions

People with existing health issues face a higher risk of side effects from MSC therapy. For example, those with diabetes might have trouble healing wounds. This could get worse with MSC therapy.

• Diabetes: Impaired wound healing and increased risk of infection.
• Heart Disease: Possible heart problems.
• Autoimmune Disorders: Risk of immune system issues.

Age and Health Status Considerations

Age and health status play big roles in side effect risks. Older people or those in poor health might face more problems. This is because they have less ability to handle treatments and might have other health issues.

Key considerations include:

• Physiological age versus chronological age.
• Presence of comorbidities.
• Overall health status.

Medication Interactions

MSC therapy can also interact with other medicines, raising side effect risks. This is true for people taking drugs that weaken the immune system, blood thinners, or certain cancer treatments. Always talk to a doctor about all your medicines before starting MSC therapy.

Medication Category	Potential Interaction
Immunosuppressive Drugs	Altered immunomodulatory effects.
Anticoagulants	Increased risk of bleeding.
Chemotherapeutic Agents	Potential for adverse effects on tumorigenesis.

Knowing these risk factors helps patients and doctors weigh the good and bad of MSC therapy. This leads to better, more informed choices.

Conclusion: Balancing Therapeutic Potentia with Side Effect Risks

The good and bad of mesenchymal stem cells (MSCs) need to be balanced. MSC therapy has shown promise in treating many medical conditions. But, it’s not without its complications.

It’s important to know the side effects. These can range from minor reactions at the injection site to serious vascular problems and genetic issues. Patients and healthcare providers must be aware of these risks.

By understanding and managing these risks, MSCs’ benefits can be fully realized. This careful approach ensures MSC therapy is safe and effective. It helps patients get the best possible results.

FAQ

References

Baranovskii, D. S., Klabukov, I. D., Arguchinskaya, N. V., Yakimova, A. O., Kisel, A. A., & Yatsenko, E. M. (2022). Adverse events, side effects and complications in mesenchymal stromal cell therapy. Stem Cell Investigation, 9, Article 25. https://doi.org/10.21037/sci-2022-025 sci.amegroups.org+1

Wang, Y., et al. (2021). The safety of MSC therapy over the past 15 years: a meta-analysis. Stem Cell Research & Therapy, 12, Article 123. https://doi.org/10.1186/s13287-021-02609-x BioMed Central

Lalu, M. M., McIntyre, L., Pugliese, C., Fergusson, D., Winston, B. W., Marshall, J. C., et al. (2012). Safety of cell therapy with mesenchymal stromal cells (SafeCell): A systematic review and meta-analysis of clinical trials. PLoS ONE, 7(10), e47559. https://doi.org/10.1371/journal.pone.0047559 PLOS

Han, X., et al. (2025). Mesenchymal stem cells in treating human diseases. Signal Transduction and Targeted Therapy, 10, Article 184. https://doi.org/10.1038/s41392-025-02313-9 Nature

Thompson, M., et al. (2020). Cell therapy with intravascular administration of MSCs: Pre-specified adverse events in clinical trials. eClinicalMedicine, 23, 100487. https://doi.org/10.1016/j.eclinm.2020.100487 The Lancet