Research Overview

TB-500

TB-500 (Thymosin Beta-4 fragment)

A synthetic fragment of Thymosin Beta-4, studied for its role in actin regulation.

What It Is

TB-500 is a synthetic peptide corresponding to the active region of Thymosin Beta-4 (TB4), a naturally occurring 43-amino-acid protein present in nearly all human and animal cells. TB-500 itself is typically the shorter, synthesized active fragment, which is why researchers use it as a stable, reproducible stand-in for studying TB4's cellular effects without needing the full-length native protein.

It is one of the most widely studied peptides in the actin-regulation literature, referenced across cell-migration, wound-model, and cardiac-tissue research contexts.

Mechanism in the Research Literature

The dominant mechanism reported in the literature is TB-500's (via its TB4 relationship) binding to G-actin, the monomeric form of the actin protein that makes up the cytoskeleton. This binding is described as sequestering G-actin and modulating the pool available for polymerization into F-actin filaments, a process central to cell migration and structural remodeling studied in vitro.

Because actin dynamics underlie how cells move and reorganize their cytoskeleton, TB-500 is frequently used in cell-migration assays and studied alongside angiogenesis-related signaling in preclinical models.

Why Purity Verification Matters Here

Actin-binding assays are highly sensitive to the exact conformation and concentration of the peptide in solution. Batch-to-batch variability in purity changes the effective concentration of active peptide in an assay well without changing what's written on the label, which can silently shift dose-response curves between experiments run on different lots. Independent HPLC and mass spec verification, tied to the specific lot in hand, is what makes actin-binding results reproducible across a research program.

Third-party tested. Lot-matched. No exceptions.

Every unrl batch is characterized by independent third-party testing before it ships, not just an in-house spec sheet. Each Certificate of Analysis is tied to the lot number printed on the vial, so what you're holding matches a specific, published result rather than a generic average.

Independent lab, not manufacturer self-testing
HPLC purity + mass spectrometry identity confirmation
Lot-specific CoA, matched to the vial in hand
Published and searchable in the public COA library

View the COA Library

Research Use Only

This page is provided for research and educational purposes only. The compound discussed is a research reference standard, not a dietary supplement, drug, or article for human or veterinary use. Nothing on this page is medical advice, dosing guidance, or a claim of safety or efficacy. No statement has been evaluated by the FDA.

Quick Reference