TB-500 is a synthetic acetylated heptapeptide (Ac-LKKTETQ) corresponding to the active actin-binding region of full-length thymosin beta-4 (Tβ4). In laboratory research it is studied for its proposed role in actin regulation, cell migration, angiogenesis, and soft-tissue-repair pathways. In the UAE, TB-500 holds no MOHAP (Ministry of Health and Prevention) registration, so Body Pharm supplies it strictly for in-vitro and preclinical research use in Emirati laboratories — not as a medicine and not for human or veterinary use.
This guide consolidates the mechanistic relationship between the TB-500 fragment and full-length Tβ4, summarises what researchers actually study, and covers generic handling and reconstitution framing for a laboratory setting. It also explains how TB-500 fits within the Body Pharm range.
What is TB-500?
TB-500 is a synthetic N-acetylated heptapeptide with the sequence Ac-Leu-Lys-Lys-Thr-Glu-Thr-Gln (Ac-LKKTETQ), corresponding to amino acids 17 to 23 of endogenous thymosin beta-4. This short sequence carries the actin-binding LKKTET motif believed to drive Tβ4's cell-migration and repair signalling. Unlike full-length Tβ4, TB-500 is chemically synthesised, lacks the remaining residues of the parent protein, and has no approved human indication in any jurisdiction.
The LKKTET motif within residues 17 to 23 has been mapped in biochemistry literature as the region responsible for sequestering G-actin monomers — the proposed mechanistic basis for Tβ4's effects on cell motility and wound repair. Synthesising only the heptapeptide is more efficient than producing recombinant full-length Tβ4 because solid-phase peptide synthesis scales well for short chains, and it concentrates the putative active site into a single fragment.
Why the acetyl group matters
Acetylation of the N-terminal leucine blocks aminopeptidase cleavage, which extends stability compared with the unmodified peptide because the enzyme cannot recognise the modified terminus. Catalogue and PubChem records for Ac-LKKTETQ list molecular weights in the approximately 826 to 830 g/mol range depending on whether the C-terminus is a free acid or an amide — a detail that matters when calculating molar quantities from a given vial.
TB-500 vs. thymosin beta-4
The fragment is studied because it concentrates Tβ4's putative actin-sequestering activity into a shorter, more soluble peptide that is easier to synthesise reproducibly than the full 43-residue protein. The trade-off is that TB-500 omits other Tβ4 domains with their own biological signatures — most notably the N-terminal AcSDKP tetrapeptide associated with anti-fibrotic and haematopoietic activity in the parent molecule, and C-terminal regions implicated in separate angiogenic and immunomodulatory signalling that the LKKTETQ fragment cannot mimic.
| Property | TB-500 (Ac-LKKTETQ) | Full thymosin beta-4 |
|---|---|---|
| Amino-acid length | 7 residues | 43 residues |
| Molecular weight | ~826–830 Da | ~4,963 Da |
| LKKTET actin-binding motif | Yes (residues 17–23) | Yes |
| AcSDKP anti-fibrotic tetrapeptide | No | Yes |
| Synthetic reproducibility | High (SPPS, 7-mer) | Moderate |
What researchers study
TB-500 is investigated for three interlinked mechanisms, all derived from preclinical in-vitro and animal work on the LKKTET-containing parent peptide.
- Actin sequestration and cell migration. The LKKTET motif binds monomeric G-actin and modulates the G-actin/F-actin equilibrium that governs cytoskeletal reorganisation. In Tβ4 biochemistry this sequestration is proposed to free migrating cells — keratinocytes, endothelial cells, myoblasts — to extend lamellipodia and traverse a wound bed in model systems.
- Angiogenesis and VEGF signalling. Preclinical Tβ4 models show upregulation of VEGF receptor expression and increased endothelial tube formation in vitro and in vivo, making angiogenesis a common focus of tissue-remodelling assays.
- Anti-inflammatory signalling. In preclinical models the effect is attributed to downregulation of NF-κB signalling and reduced expression of pro-inflammatory cytokines such as TNF-α and IL-1β in injured tissue.
It is important to frame all of these as observations in animal and in-vitro models. Controlled human data confirming these mechanisms for the Ac-LKKTETQ fragment specifically are not established, and current reviews still cite the older full-length Tβ4 work rather than fragment-specific outcomes.
Handling and reconstitution (research framing)
In a research setting, TB-500 is typically supplied as a lyophilised white powder and reconstituted with bacteriostatic or sterile water prior to use in a laboratory workflow. The notes below reflect standard peptide-laboratory practice and are provided for handling context only.
- Reconstitution. Add the diluent slowly down the inside wall of the vial rather than directly onto the lyophilised cake, and swirl gently until clear; direct contact and shaking can cause foaming and peptide denaturation. Working concentration follows directly from the diluent volume added to a given vial mass.
- Storage. Keep reconstituted vials refrigerated at 2–8 °C, protected from light in the original carton or an opaque container, and avoid repeated freeze-thaw cycles. Unreconstituted lyophilised powder is stable for substantially longer periods when kept frozen.
- Consistency. Because handling variables affect solubility and stability, using a consistently produced, quality-controlled vial helps keep experimental conditions reproducible across a research programme.
TB-500 in the Body Pharm UAE range
TB-500 sits within a small cluster of peptides commonly investigated for tissue repair, alongside BPC-157. The two are paired in research protocols because they are proposed to target mechanistically distinct phases of repair — TB-500 associated with cell migration and neovascularisation, and BPC-157 with angiogenic and collagen-organisation effects — rather than because any controlled trial has validated the combination. No peer-reviewed study has formally tested co-administration of the two peptides.
Body Pharm pairs TB-500 with BPC-157 in a single research pen. See the BPC-157 + TB-500 32 Pen — a combined format used to study the two repair-research peptides together.
Research use only in the UAE
TB-500 is not registered as a medicine by any regulatory authority and has no approved human therapeutic indication. All peptides are supplied strictly for laboratory research use only — not for human or veterinary use, and not for consumption, diagnosis, or treatment.