Stem Cells in the U.S. and Abroad: Clinical Use, Regulation, and Outcomes

This blog summarizes key insights from an educational webinar presented by John Ferrell III, MD, highlighting clinically relevant concepts discussed during the session.

Introduction: Clarifying a Complex and Evolving Space

During a recent educational webinar hosted by APEX Biologix, Dr. John Ferrell explored a topic that continues to generate both clinical interest and uncertainty: the role of stem cell therapy in musculoskeletal care, and how its use differs between the United States and international settings.

The discussion focused on a critical intersection of regenerative medicine, mechanism, regulation, and real-world application with the goal of helping clinicians better understand what is currently supported, what is permitted, and how to evaluate emerging options.

Rethinking “Stem Cells”: From Replacement to Signaling 

One of the most important concepts introduced early in the webinar is the evolving understanding of mesenchymal stem cells (MSCs).

MSCs, originally described by Dr. Arnold Caplan, were first defined for their ability in laboratory settings to differentiate into cartilage, tendon, or bone cell types once injected. Over time, it became clear that this behavior is primarily observed in vitro.

In clinical application, MSCs do not predominantly function by transforming into new tissue. Instead, they act through signaling mechanisms, serving as a biologic “beacon” that helps recruit the body’s own repair processes and modulate the local healing environment. Based on this evolving understanding, Caplan later proposed the term medicinal signaling cells to more accurately reflect their role in vivo.

MSC are your body’s own pharmacy - they don’t rebuild tissue, they single your body to heal itself.”

Regulatory Framework: Understanding What Is Permitted 

In the United States, biologic therapies are classified by the FDA based on how they are processed and used. Minimally manipulated, autologous therapies that maintain homologous use, generally fall within the 361 regulatory pathway and may be utilized in accordance with applicable FDA guidelines.

In contrast, therapies involving greater manipulation, including enzymatic processing, culture expansion, or the use of birth tissue products, are regulated under the 351 pathway and require formal FDA approval through investigational or biologics licensing processes.

This distinction underscores an important clinical consideration: not all therapies described as “stem cells” are equivalent in either regulatory status or biologic behavior.

MFAT: Mechanism, Evidence, and Clinical Relevance 

Microfragmented adipose tissue represents one of the primary autologous biologic options currently utilized in musculoskeletal medicine.

The processing of adipose tissue is designed to preserve the native cellular environment, maintaining structural integrity and supporting a signaling-based mechanism of action. Within this environment, pericytes and medicinal signaling cells contribute to modulation of inflammation and recruitment of stem cells.

A growing body of literature supports the use of MFAT, including Level 1 evidence in osteoarthritis. Across more than 160 peer-reviewed orthopedic publications, findings consistently demonstrate favorable clinical outcomes, with many studies reporting success rates exceeding 80% in osteoarthritis populations.

In a referenced study, patients with advanced knee osteoarthritis experienced meaningful improvements in pain and function following a single injection, with benefits sustained over a two-year period.

BMAC: Concentrated Cellular Signaling and Structural Applications 

Bone marrow aspirate concentrate offers another autologous approach, characterized by a concentrated population of signaling cells, stem cells, and growth factors.

The biologic rationale for BMAC lies in its ability to support both inflammatory modulation and tissue repair signaling, particularly in environments involving subchondral bone or more advanced structural pathology.

Long-term data suggests that BMAC may play a role in delaying disease progression in certain osteoarthritic populations, with additional applications across tendon, cartilage, and bone-related conditions.

U.S. vs International Therapies: Safety Considerations and Biologic Limitations 

The webinar also examines the growing interest in seeking regenerative therapies outside of the United States.

While some international clinics operate under rigorous protocols, variability in regulation, quality control, and oversight remains a key consideration. Additionally, there is limited direct comparative data evaluating these therapies against established autologous approaches used domestically.

Potential risks associated with less regulated environments include infection, immune reactions, and inconsistencies in product quality.

Additionally, certain delivery methods such as intravenous administration may present biologic limitations, with a significant proportion of cells not reaching target tissues due to pulmonary sequestration.

The Autologous Advantage in Clinical Practice 

Autologous biologic therapies offer practical advantages, including reduced risk of immune response, preserved cell viability, and the ability to perform procedures within a controlled, same-day clinical setting.

This approach supports consistency in both processing and application, reinforcing its role in current regenerative workflows.

Evolving Legislation and the Role of Federal Oversight 

Recent legislative developments at the state level have introduced new considerations; however, federal FDA oversight continues to govern the broader regulatory framework.

For clinicians, this reinforces the importance of aligning biologic use with established regulatory pathways.

Cost, Value, and Continuity of Care 

Treatment decisions in regenerative medicine extend beyond procedural cost alone.

In this segment, Dr. Ferrell provides a practical comparison of treatment pathways, emphasizing that cost should be evaluated within the broader context of safety, access to care, and long-term management.

Rather than focusing solely on upfront pricing, clinicians and patients must consider the full scope of the treatment, including follow-up, complication management, and regulatory oversight.

Clinical Decision-Making: Matching Therapy to Pathology 

Biologic selection should be guided by pathology, severity, and treatment goals.

PRP remains a strong option in earlier-stage conditions, while MFAT and BMAC may be considered in more advanced or structural cases. This reflects a broader shift toward context-driven, patient-specific treatment strategies.

Conclusion: A Measured Approach to Regenerative Medicine

As regenerative medicine continues to evolve, its successful integration depends on a clear understanding of biologic mechanisms, regulatory frameworks, and clinical application.

This discussion reinforces the importance of approaching biologics not as a single solution, but as part of a broader, evidence-guided treatment strategy.

Continue Your Education with APEX

Access the full on-demand webinar and explore additional clinician-focused resources, including research articles, procedural videos, and expert-led training in the APEX Resource Library.

Watch the full webinar on-demand:
https://apexbiologix.com/resource-library

Explore additional resources in the APEX Resource Library:
https://apexbiologix.com/resource-library

Clinicians interested in hands-on training, procedural education, and practice implementation strategies can explore the upcoming XCELL RISE - Sports Medicine event hosted at the XCELL Learning Center located in Clearwater, Florida. XCELL RISE – Sports Medicine is not a traditional conference. It is a purpose-built educational experience designed to meet clinicians where they are in their regenerative journey, from foundational biologic science to advanced procedural execution.

References

Caplan, A. Mesenchymal Stem Cells: Time to Change the Name!. Stem Cells Transl Med. 2017;6(6):1145-1451. doi: 10.1002/sctm.17-0051

Heidari, N., et al. Microfragmented Adipose Tissue Injection (MFAT) May Be a Solution to the Rationing of Total Knee Replacement: A Prospective, Gender-Bias Mitigated, Reproducible Analysis at Two Years. Stem Cells In. 2021;2021:9921015. doi: 10.1155/2021

Veronesi, F., et al. Adipose Tissue-Derived Minimally Manipulated Products versus Platelet-Rich Plasma for the Treatment of Knee Osteoarthritis: A Systematic Review of Clinical Evidence and Meta-Analysis. J Clin Med. 2023;13(1):67. doi:10.3390/jcm13010067

Hernigou, P., et al. Subchondral bone or intra-articular injection of BMC mesenchymal stem cells in bilateral knee osteoarthritis: what better postpone knee arthroplasty at fifteen years? A Randomized Study. Int Orthop. 2021;45(2):391-399. doi:10.1007/s00264-020-04687-7

Pabinger, C., et al. IntraArticular Injection of Bone Marrow Aspirate Concentrate (Mesenchymal Stem Cells) in KL Grade III and IV Knee Osteoarthritis: 4 Year Results of 37 Knees. Sci Rep. 2024;14(1):2665. doi:10.1038/s41598-024-51410-2

Disclaimer
This blog post is a summary of an educational session and is provided for informational purposes for healthcare professionals. The perspectives shared reflect the clinical experience and opinions of the speaker(s) and do not necessarily represent the views of APEX Biologix. This content is not medical advice and is not intended to establish a standard of care, diagnose, or recommend treatment for any individual patient. Clinicians should evaluate all therapies using their independent clinical judgment, applicable regulations, and the most current evidence.