Medical applications · investigational

Autologous biologic therapies for TBI & CTE.

An investigational, patient-derived procedure for selected adults with a history of traumatic brain injury and persistent post-traumatic symptoms, or symptom patterns consistent with chronic traumatic encephalopathy (CTE). 

Post-concussion syndrome Repetitive head trauma Suspected CTE Cognitive recovery support Autonomic / sleep symptoms

This procedure is investigational. No stem cell or cellular therapy is approved by the FDA for TBI, CTE, or post-traumatic neurodegeneration. CTE is a neuropathological diagnosis that cannot be definitively confirmed during life. Read the full regulatory disclosure ↓

What it is

Pioneering experimental biologic therapies for TBI and CTE

Boulder Biologics offers investigational autologous biologic procedures for selected individuals with a history of traumatic brain injury (TBI) and persistent post-traumatic symptoms. These procedures are also explored in patients with symptom patterns consistent with chronic traumatic encephalopathy (CTE), recognizing that CTE is a neuropathological diagnosis that cannot be definitively confirmed during life.

The approaches described on this page are experimental, based on evolving scientific evidence, and offered only after a comprehensive informed-consent process, consistent with our approach to Long COVID and intranasal biologic therapies.

Shared biological features

Secondary injury, not just the initial impact.

As with Long COVID, chronic symptoms following TBI and repetitive head injury are increasingly understood to arise from secondary injury mechanisms, rather than from just the first mechanical insult alone.

01 · Neuroinflammation

Persistent neuroinflammation.

Sustained activation of microglia, astrocytes, and peripheral immune signaling pathways contributes to ongoing neuronal stress and dysfunction long after the initial injury. This immune dysregulation parallels inflammatory mechanisms described in Long COVID-associated cognitive impairment.

Refs. 7, 8
02 · Neurovascular

Neurovascular & BBB dysfunction.

Disruption of the blood–brain barrier and cerebral microvasculature impairs nutrient delivery, waste clearance, and neurovascular coupling, mechanisms now recognized in both post-traumatic and post-infectious neurological syndromes.

Refs. 2, 5, 6
03 · Cumulative

Progressive or cumulative injury.

In individuals with repetitive head impacts, chronic inflammation, axonal injury, and abnormal protein accumulation may drive progressive cognitive, behavioral, and motor symptoms over time.

Refs. 1, 7

About the biology

Paracrine signaling, not neuronal replacement.

Mesenchymal stromal cells (MSCs) are non-hematopoietic cells present in bone marrow and other tissues. Consistent with FDA-aligned scientific consensus, their primary within the body activity is paracrine and immunomodulatory, not direct neuronal differentiation or replacement of brain tissue.

As with our Long COVID program, we emphasize that any potential benefit arises from:

  • Immune modulation rather than immune suppression
  • Support of endogenous repair environments, not cell replacement
  • Neurovascular and glial signaling effects, not regeneration of lost neurons

Claims of routine differentiation into functional brain cells are not supported in human clinical data and are intentionally avoided.

MechanismParacrine · immunomodulatory
Immune leverModulates microglia & peripheral signaling
Vascular leverEndothelial & BBB support
Tissue leverGrowth-factor signaling for repair environment
What it is notNeuron replacement · neuroregeneration

Rationale

Why investigators are studying MSC-containing biologics.

Immune system modulation.

Preclinical and early clinical studies suggest MSC-associated biologics may reduce pro-inflammatory cytokines and influence immune cell behavior after TBI, similar to mechanisms hypothesized in Long COVID.

Refs. 6–8

Neurovascular & tissue-support signaling.

Animal models demonstrate increased expression of growth factors involved in angiogenesis and neurovascular support following administration of marrow-derived stromal cells. These effects are thought to improve the biologic environment for recovery, rather than replacing damaged neurons.

Refs. 5, 6

Limiting secondary injury cascades.

By influencing inflammation, apoptosis pathways, and microvascular integrity, MSC-associated signaling may help limit the secondary injury processes that contribute to chronic dysfunction and neurodegeneration. Refs. 1, 5, 6

WHAT TO EXPECT

How the Procedure Works

This investigational approach mirrors the framework used in our Long COVID program. No donor cells, no culture expansion, no genetic modification, no manufactured cellular products.

Step 01

Consultation

Full medical history, imaging review, and case conference. Symptom timeline and prior care are reviewed before any procedure is scheduled.

Pre-treatment
Step 02

Bone marrow aspiration

From the posterior superior iliac spine (PSIS) under local anesthesia and image guidance.

~20–30 min
Step 03

Filtration & minimal processing

Bone marrow aspirate is filtered and minimally processed in our on-site lab; cellular components may be concentrated.

~1-2 hrs
Step 04

Autologous administration

Intravenous (IV) delivery and, in selected cases, intranasal delivery for CNS access via olfactory / trigeminal pathways. Intranasal delivery remains investigational.

Same-visit
Step 05

Longitudinal follow-up

Structured neurocognitive measures and symptom tracking over time.

Long-term

Safety

How we frame safety

  • Autologous biologics reduce immune rejection risks seen with donor-derived products.
  • Published studies suggest acceptable short-term safety, but long-term efficacy is unknown.
  • Not all patients improve; response cannot be predicted.
  • Patients are screened carefully. 

Current evidence

Clinical outcomes: current state.

Evidence for MSC-based biologics in TBI and suspected CTE is preliminary, derived largely from animal models, small human studies, and early-phase clinical investigations. This treatment is experimental, supportive, care - not disease-modifying therapy. 

Reported improvements in some patients include memory and attention, cognitive endurance, neurofatigue, and autonomic symptoms. However:

  • Results are inconsistent.
  • Controlled trials specific to CTE are lacking.
  • No therapy is proven to prevent, halt, or reverse CTE.

Is this you?

A consultation is how we figure that out.

Eligibility is decided case by case after a multi-visit workup that includes imaging review and, where relevant, a case conference.

Likely worth a conversation

  • Persistent post-concussion symptoms past 6+ months
  • History of repetitive head trauma in sport or service
  • You can produce records of injury history, imaging, and prior care
  • Open to a multi-visit workup before any procedure
  • You understand this is investigational territory
  • Realistic expectations, investigational supportive care, not a cure or disease-modifying therapy

WE WANT TO BE CLEAR

FDA Regulatory Disclosure

Regulatory status

  • No stem cell or cellular therapy is FDA-approved for TBI, CTE, or Long COVID.
  • The procedures described are investigational.
  • No claims are made regarding cure, neuroregeneration, or disease modification.
  • Outcomes vary; no benefit is guaranteed.

This page aligns with FDA guidance on regenerative medicine marketing and avoids unsubstantiated claims.

Terminology and scientific accuracy

Consistent with FDA guidance and current scientific consensus, we avoid claims that mesenchymal stromal cells differentiate into functional brain cells in vivo. Any potential benefit is described as paracrine signaling, immune modulation, and support for endogenous repair, consistent with the prevailing literature.

References to "stem cells" on this page reflect cellular populations contained within autologous bone marrow–derived biologic material, not manufactured or expanded stem cell products.

Autologous vs donor-derived cells

The FDA has raised particular concern regarding allogeneic (donor-derived) stem cell products, including umbilical cord, placental, and amniotic products, marketed outside of approved clinical trials.

At Boulder Biologics:

  • Only autologous (patient-derived) cellular material is used
  • No donor cells are administered
  • No culture expansion, genetic modification, or manufacturing of cells occurs

Investigational nature and informed consent

  • Patients are informed that this approach is experimental.
  • Clinical response is variable and unpredictable.
  • Some patients may experience no benefit.
  • Long-term efficacy data for TBI and suspected CTE are not yet established.

Participation is voluntary, and treatment is undertaken only after a comprehensive informed-consent process.

Intranasal delivery, investigational

As with Long COVID-associated cognitive dysfunction, intranasal delivery is explored as a route to allow biologic signaling molecules to access the central nervous system via olfactory and trigeminal pathways. Important alignment points:

  • Intranasal delivery is investigational.
  • It is not FDA-approved for neurological disease treatment.
  • It is discussed as a potential access route, not a proven therapeutic pathway.

References

Selected literature.

  1. Schepici G, Silvestro S, Bramanti P, Mazzon E. Traumatic brain injury and stem cells: an overview of clinical trials and future therapeutic approaches. Medicina (Kaunas). 2020;56(3):137.
  2. Greene C, Connolly R, Brennan D, et al. Blood–brain barrier disruption and sustained systemic inflammation in individuals with long COVID-associated cognitive impairment. Nat Neurosci. 2024;27:421–432.
  3. Wislet-Gendebien S, Laudet E, Neirinckx V, Rogister B. Adult bone marrow stem cells for neurodegenerative disorders. J Biomed Biotechnol. 2012;2012:601560.
  4. Sekiya I, Larson BL, Smith JR, et al. Expansion of human adult stem cells from bone marrow stroma. Stem Cells. 2002;20(6):530–541.
  5. Mahmood A, Lu D, Qu C, et al. Human marrow stromal cell treatment provides long-lasting benefit after TBI in rats. Neurosurgery. 2005;57(5):1026–1031.
  6. Mahmood A, Lu D, Chopp M. IV administration of marrow stromal cells increases growth factor expression after TBI. J Neurotrauma. 2004;21(1):33–39.
  7. McKee CA, Lukens JR. Emerging roles for the immune system in traumatic brain injury. Front Immunol. 2016;7:556.
  8. Hasan A, Deeb G, Rahal R, et al. Mesenchymal stem cells in the treatment of traumatic brain injury. Front Neurol. 2017;8:28.
  9. Galeano C, Qiu Z, Mishra A, et al. The route by which intranasally delivered stem cells enter the CNS. Cell Transplant. 2018;27(3):501–514.

Schedule a TBI / CTE consultation

Tell us about your case.

Our team will review your injury history, imaging, and current symptoms, and tell you honestly whether this investigational approach fits your case or whether another path makes more sense.

Or call 720-550-6175
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