What primary receptor cascades and in vitro signaling axes are modulated by TB-500?

Pre-clinical studies indicate TB-500 engages primary pathways: Binds monomeric G-actin in 1:1 stoichiometry, preventing premature polymerization and facilitating rapid cellular motility. Stimulates matrix metalloproteinase production (MMP-2 and MMP-9) during controlled endothelial reorganization. Additional investigations explore cellular migration, receptor binding affinities, and kinase activation in vitro.

What is the recommended reconstitution diluent and sterile handling protocol for TB-500?

Lyophilized TB-500 cakes must be reconstituted using Bacteriostatic 0.9% Benzyl Alcohol USP. Introduce the diluent gently along the internal glass wall under a laminar flow hood, allowing passive dissolution without mechanical vortex shear or high-velocity liquid agitation.

What are the storage temperature thresholds and solution kinetics for TB-500?

Lyophilized vials require desiccated storage at -20°C dry vacuum-sealed (stable 24 months). Once reconstituted into an aqueous solvent, the peptide solution must be stored at 2°C to 8°C refrigerated (stable 21 days) protected from UV degradation. The laboratory stability window is Highly sensitive to mechanical shear and agitation during dissolution. Avoid repeated freeze-thaw cycles.

Is TB-500 lawful to purchase and possess for laboratory research in the United Kingdom?

Yes. Non-scheduled synthetic research peptides like TB-500 are entirely legal to acquire, import, and hold for bona fide laboratory experimentation in the UK. However, under Regulation 46 of the Human Medicines Regulations 2012 (SI 2012/1916), supply or marketing for human clinical administration without MHRA authorization is strictly unlawful.

UK Academic MonographTissue Repair & AngiogenesisIn Vitro Laboratory Only

TB-500

Q: What is the CAS registry number, molecular formula, and mass of TB-500?

TB-500 (Thymosin Beta-4 Active Hexapeptide Domain (Ac-LKKTET-OH)) is indexed in the CAS Registry under #77591-33-4. Its empirical molecular formula is C212H350N56O78S with a monoisotopic molecular weight of 4963.50 g/mol. It is cataloged under the Tissue Repair & Angiogenesis research classification.

Thymosin Beta-4 Active Hexapeptide Domain (Ac-LKKTET-OH)

PubChem Molecular SpecsValidated

CAS Registry:77591-33-4

Chemical Formula:C212H350N56O78S

Monoisotopic MW:4963.50 g/mol

PubChem CID:16132341

Primary Amino Acid Sequence (6 residues)

N-terminus → C-terminus

1Ac-Leu

2Lys

3Lys

4Thr

5Glu

6Thr-OH

Pre-Clinical Overview

TB-500 represents the synthetic active fragment of Thymosin Beta-4, a major physiological actin-sequestering protein. Studied in British biomedical research for its ability to regulate G-actin polymerization, promote keratinocyte migration, and downregulate myofibroblast differentiation.

Independent Laboratory Audit

Verified UK Suppliers for TB-500

5 Audited British & European Sources

Supplier	Assay Purity	Reagent Format	Dispatch Location	Notes
PharmaGrade Store	≥99.0% (HPLC)	vial	United Kingdom (Royal Mail 24)	High-purity lyophilized TB-500 vials with batch-specific analytical certification.
Direct Peptides	≥98.9% (HPLC)	vial	UK Hub & Europe	Lyophilized peptide vials and synergistic tissue recovery research stacks.
Direct Sarms	≥98.5% (HPLC)	vial	United Kingdom Express	Analytical grade vials tested for cellular motility and microvascular assays.
Peptide Works	≥98.8% (HPLC)	vial	Manchester UK Hub	Northern UK laboratory dispatched lyophilized reagent vials with sequence COA.
PharmaLab Global	≥99.2% (HPLC)	vial	London UK Hub	Triple-stage assayed vials and pre-calibrated laboratory pens.

Biochemical Mechanisms of Action

Molecular Signaling Pathways

1Binds monomeric G-actin in 1:1 stoichiometry, preventing premature polymerization and facilitating rapid cellular motility.
2Stimulates matrix metalloproteinase production (MMP-2 and MMP-9) during controlled endothelial reorganization.
3Upregulates vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) transcription.
4Inhibits cellular apoptosis in cardiomyocytes and vascular endothelial cells subjected to oxidative hypoxia.

Pre-Clinical Laboratory Handling

Laboratory Evaluation Guidelines

Frequently investigated alongside BPC-157 in dual-pathway tissue remodeling protocols. Subject to strict laboratory handling and reconstituted under laminar flow hoods for in vitro experimentation.

Aseptic Dissolution & StorageUK Lab Standard

Recommended Diluent:Bacteriostatic 0.9% Benzyl Alcohol USP

Lyophilized Storage:-20°C dry vacuum-sealed (stable 24 months)

Reconstituted Storage:2°C to 8°C refrigerated (stable 21 days)

Solution Stability:Highly sensitive to mechanical shear and agitation during dissolution

Academic Biochemical Monograph

Receptor Affinity, SPPS Synthesis & Pharmacokinetics

Standardized chemical parameters, solid-phase synthesis criteria, and quantitative receptor affinity benchmarks for TB-500.

Target ReceptorsBinding Kinetics

Primary Receptor Cascade

Monomeric G-Actin (Actin-Sequestering Domain LKKTET)

Binding Affinity (Kd / Ki)

Kd ≈ 0.7 - 2.0 μM (1:1 stoichiometric binding to monomeric G-actin)

Receptor Family

Intracellular Cytoskeletal Actin Chaperone

Downstream Effectors

Inhibition of G-actin polymerization into F-actin filaments
MMP-2 and MMP-9 matrix metalloproteinase transcription
Endothelial progenitor cell migration and tube reorganization

SPPS MethodologyISO Criteria

Synthesis Protocol

Fmoc Solid-Phase Peptide Synthesis (SPPS)

N-Terminal / C-Terminal Mod

N-alpha-acetylated (Ac-Leu-) · Free carboxylic acid (-Thr-OH)

Acid Cleavage Cocktail

TFA / EDT / TIS / H2O (90:5:2.5:2.5 vol/vol)

HPLC Retention Standard

RP-C18: 14.8 min (0.1% TFA in H2O/ACN gradient)

PharmacokineticsIn Vitro / In Vivo

Elimination Half-Life

t1/2 ≈ 2.1 hours (ex vivo plasma proteolysis)

Primary Degradation Pathway

Carboxypeptidase cleavage of N-terminal acetylated motif

Bioavailability Profile

Reconstituted lyophilized reagent (in vitro model)

Renal Filtration Threshold

Glomerular filtration threshold compliant (MW: 4,963.50 Da)

Quantitative Pre-Clinical & Clinical Evidence Matrix

Documented Biochemical Endpoints & Statistical Significance

Study Design	Cohort (n)	Measured Biological Endpoint	Statistical Significance	NCBI Citation
In Vitro Assay	n = 24 keratinocyte migration assays	Scratch-wound closure velocity & actin stress fiber reorganization	p < 0.001 vs control	PMID 10469598
Preclinical In Vivo	n = 40 dermal punch biopsy models	Epithelial migration rate & neo-vascular capillary density	p < 0.05 vs sham	PMID 12569117

Peer-Reviewed Academic Citations

Indexed Scientific Literature

Thymosin beta4 promotes dermal healing in pre-clinical wound models

Wound Repair and Regeneration (2003) · Malinda KM, Sidhu GS, Mani H, et al.

Key Finding: Observed significant acceleration in re-epithelialization and collagen deposition in dermal tissue explants.

PubMed PMID: 12654014

BIOCHEMICAL & REGULATORY Q&A

Curated Scientific Q&A for TB-500

Authoritative pre-clinical, analytical, and statutory handling guidelines for laboratory researchers.

5 Curated Questions

TB-500 (Thymosin Beta-4 Active Hexapeptide Domain (Ac-LKKTET-OH)) is indexed in the CAS Registry under #77591-33-4. Its empirical molecular formula is C212H350N56O78S with a monoisotopic molecular weight of 4963.50 g/mol. It is cataloged under the Tissue Repair & Angiogenesis research classification.

Citation Benchmark: PubChem CID 16132341; British Pharmacopoeia Appendix III

Biological Pathway Correlates

More Reagents in Tissue Repair & Angiogenesis

View Pathway Hub

Mixed Pre-ClinicalCAS 137525-51-0

BPC-157

Body Protection Compound-157 Pentadecapeptide

C62H98N16O221419.55 g/molTissue Repair & Angiogenesis

BPC-157 is a stable 15-amino acid synthetic pentadecapeptide fragment originally derived from human gastric juice protein BPC. Evaluated in UK academic and biotechnology laboratories as an analytical benchmark for focal adhesion kinase (FAK) activation and endothelial tube formation assays.

Verified UK Sourcing Partners:

PharmaGrade Store (≥99.2% (HPLC))Direct Peptides (≥99.1% (HPLC))Direct Sarms (≥98.8% (HPLC))Peptide Works (≥99.0% (HPLC))PharmaLab Global (≥99.4% (HPLC))

View Full Technical Monograph