Overview

TB-500 is a synthetic peptide corresponding to the active region of Thymosin Beta-4 (Tβ4), a 43-residue actin-sequestering protein expressed in most mammalian tissues. Where Tβ4 itself is the full endogenous protein, TB-500 in research literature typically refers to a shorter synthetic fragment retaining the key actin-binding motif; nomenclature varies between sources and product data sheets, and readers should verify what a given supplier actually ships.

Preclinical research has explored Tβ4 and TB-500 in wound-healing, cardiac-repair, corneal-injury, and neurological-injury models. Some human trials of full Tβ4 have been conducted, primarily in dermal-wound and dry-eye contexts.

Mechanism (as reported)

  • Actin regulation. Tβ4 binds monomeric G-actin and prevents polymerisation; this regulation of the cytoskeleton is central to cell migration during tissue repair.
  • Cell migration and angiogenesis. Animal studies report increased endothelial-cell migration and formation of new vasculature at injury sites in Tβ4-treated tissue.
  • Anti-inflammatory action. Preclinical work describes downregulation of pro-inflammatory cytokines and increased expression of tissue-repair mediators.
  • Progenitor-cell recruitment. Cardiac-injury models report recruitment of epicardial progenitor cells and reactivation of embryonic-repair pathways in adult tissue.

Research findings

  • Cardiac repair. Animal studies report improved outcomes after myocardial infarction with Tβ4 administration, including recruitment of resident cardiac progenitors (Smart et al., Nature, 2007; PMID 17558415).
  • Dermal wound healing. Multiple animal models report accelerated wound closure and improved dermal-regeneration quality.
  • Corneal healing. Human trials of topical Tβ4 for dry eye and neurotrophic keratitis have been reported.
  • Hair biology. Preclinical work reports Tβ4 involvement in hair-follicle stem cell activation.

Common dosing (animal studies)

The literature and community writeups typically discuss TB-500 doses in the range of 2–5 mg per administration, given 2–3 times per week during an initial loading period (commonly 4–6 weeks), followed by less frequent maintenance dosing. These figures come from research and community sources — not from clinical guidelines — and are reported here for reference.

Reconstitution

A common reconstitution reported in the literature is 5 mg of peptide in 2 mL bacteriostatic water, producing a 2,500 mcg/mL solution. A 2,500 mcg (2.5 mg) research dose corresponds to 1.0 mL, or 100 units on a U-100 insulin syringe — i.e., the full barrel.

Storage

Lyophilised TB-500 is generally reported as stable for shipping at room temperature. Once reconstituted, the peptide is typically stored refrigerated at 2–8 °C and used within 30–60 days per manufacturer data sheets. Avoid repeated freeze-thaw cycles.

  • BPC-157 — frequently studied in parallel and combined in tissue-repair research contexts.

Common stacks

References

  • Smart, N., et al. (2007). “Thymosin beta4 induces adult epicardial progenitor mobilization and neovascularization.” Nature, 445. PMID 17558415.
  • Malinda, K. M., et al. (1999). “Thymosin beta4 accelerates wound healing.” Journal of Investigative Dermatology, 113(3). PMID 10469339.
  • Sosne, G., et al. (2010). “Thymosin beta 4 promotes corneal wound healing.” Annals of the New York Academy of Sciences, 1194. PMID 20536464.
  • Goldstein, A. L., et al. (2005). “Thymosin beta4: actin-sequestering protein moonlights to repair injured tissues.” Trends in Molecular Medicine, 11(9). PMID 16112613.