BPC-157 builds the roads. TB-500 drives the cars.
TB-500 is the synthetic version of Thymosin Beta-4 — your body's actin-regulating protein. While BPC-157 concentrates repair at a specific injury site, TB-500 works systemically: promoting cell migration, building new blood vessels, and reducing inflammation throughout your body. One targets the repair. The other delivers the cells to do it. Together they're called the Wolverine Stack. Neither is as effective alone. The mechanism is actin polymerization and angiogenesis. What matters: injuries that wouldn't heal on their own start improving in weeks.
TB-500
Thymosin Beta-4 (synthetic)
TB-500 is the synthetic 43-amino-acid analog of Thymosin Beta-4, a naturally occurring actin-sequestering protein found in virtually every mammalian tissue — platelets, white blood cells, heart, brain, skin, and muscle. Unlike site-specific repair peptides, TB-500 acts systemically: it promotes actin polymerisation, drives endothelial cell migration, stimulates angiogenesis, and reduces pro-inflammatory signalling across multiple tissue types simultaneously. It has been studied for cardiac repair post-myocardial infarction, corneal wound healing, dermal repair, neuroprotection, and musculoskeletal recovery. When stacked with BPC-157 — the combination known as the Wolverine Stack — the two peptides create a complementary repair cascade: BPC-157 concentrates angiogenesis and tenocyte recruitment at the specific injury site while TB-500 delivers systemic cellular machinery and anti-inflammatory cover to support recovery throughout the body.
Technical details
- CAS number
- 77591-33-4
- Molecular formula
- C₁₅₀H₂₄₀N₄₀O₄₅S
MECHANISM OF ACTION
At its core, TB-500 is an **actin-regulating peptide**. It binds to G-actin monomers — the soluble, unpolymerised form of actin — and modulates the ratio between G-actin and F-actin (the polymerised filamentous form). By sequestering G-actin, TB-500 frees up actin-binding proteins to promote cytoskeletal reorganisation at the injury site. The practical result: cells at the wound margin can migrate more rapidly, fibroblasts can proliferate, and the structural scaffolding for new tissue forms faster. This mechanism is why TB-500's effects are so broad — almost every repair process depends on cell migration, and cell migration depends on actin dynamics. The second major pathway is **angiogenesis and vascular remodelling**. TB-500 upregulates the expression of matrix metalloproteinases (MMPs) and vascular endothelial growth factor (VEGF), creating both the enzymatic clearance and the vascular infrastructure for sustained tissue repair. Endothelial cells migrate and form new capillary tubes more readily in the presence of TB-500 — a process confirmed in multiple in vitro tube-formation assays and in vivo wound models. The difference from BPC-157 is distribution: BPC-157 concentrates angiogenic signalling at a specific injury site; TB-500's systemic distribution means it works across multiple injury sites simultaneously, which is why it is preferred for diffuse injuries or full-body recovery protocols. The third pathway is **anti-inflammatory and anti-apoptotic**. TB-500 reduces pro-inflammatory cytokines — specifically TNF-α and IL-1β — while promoting M2 macrophage polarisation, the anti-inflammatory phenotype associated with tissue repair rather than tissue destruction. It also inhibits caspase-3 activation, reducing apoptosis in mechanically stressed or ischaemic tissue. This combination — pro-repair, anti-inflammatory, anti-apoptotic — is what distinguishes TB-500 from simple growth factor administration and explains why it performs particularly well in chronic injury contexts where inflammation is the primary obstacle to healing.
RESEARCH HIGHLIGHTS
Thymosin Beta-4 is the primary G-actin sequestering protein in mammalian cells, regulating actin dynamics and playing a central role in wound healing, cell migration, and tissue protection across multiple organ systems.
TB4 promotes cardiac repair and regeneration after myocardial infarction by activating cardiac progenitor cells and stimulating angiogenesis in the ischaemic myocardium.
Thymosin Beta-4 accelerated dermal wound closure and increased collagen deposition in excisional wound models, with histological confirmation of improved tissue architecture in healed tissue.
Topical and systemic Thymosin Beta-4 promoted corneal epithelial healing and reduced inflammatory cell infiltration after corneal injury, establishing a role in ophthalmic tissue repair.
Thymosin Beta-4 administration after experimental stroke promoted neuroblast migration, synaptic plasticity, and functional recovery, suggesting a neuroprotective and neuroregenerative mechanism.
RESEARCH PROTOCOLS
For laboratory use only. Not medical advice.
Start with a single weekly injection to assess tolerance. Some people experience a mild loading-phase fatigue in the first 1-2 weeks as their body adapts to increased cell migration activity — this typically resolves by week 3.
Often stacked with BPC-157 (the 'Wolverine Stack'). Can inject in belly fat — systemic distribution.
Loading dose protocol: 2.5mg 2x/week for first 2 weeks, then reduce to maintenance.
PAIRS WELL WITH
ORDER
SAFETY & CONTRAINDICATIONS
- History of cancer (promotes angiogenesis — use with caution)
- Pregnancy or breastfeeding
- Active autoimmune conditions
TB-500 has a limited formal human safety dataset, but community reports from years of use are consistently encouraging. The most commonly reported experience is a loading-phase fatigue in weeks 1-2 — a transient drop in energy that likely reflects the metabolic cost of upregulated cell migration and tissue remodelling activity; it typically resolves by week 3 and is interpreted by most users as a signal that something is working. Injection site reactions are mild and less frequent than with BPC-157. There are no community reports of hepatotoxicity, thyroid disruption, or hormonal interference. The theoretical oncology concern — that promoting angiogenesis and cell migration could accelerate tumour growth — applies here as it does to BPC-157 and any angiogenic peptide; standard guidance is to avoid use in anyone with active malignancy or a known predisposition. Long-term human safety data does not exist beyond anecdotal reports. For the majority of healthy adults using standard doses for injury recovery, the observed risk profile is low — though the absence of randomised controlled trial data means this assessment is provisional.
For research and laboratory use only. Not intended for human consumption. Not for diagnostic or therapeutic purposes.