Is TB-500 the same as thymosin beta-4?

No. Full-length thymosin beta-4 is a 43-residue protein. TB-500 (as PepDirect supplies it) is the 7-residue acetylated fragment. They are chemically distinct and their research evidence bases should not be conflated.

What TB-500 identity does PepDirect supply?

PepDirect's TB-500 is the acetylated Tβ4 17–23 fragment (N-acetyl-LKKTETQ), CAS 885340-08-9, molecular formula C38H68N10O14, molecular weight ~889.0 g/mol. Lot-specific identity is documented in the corresponding COA.

Is TB-500 the same as BPC-157?

No. TB-500 and BPC-157 are distinct research peptides with different sequences, different parent proteins and different published research histories. They are frequently paired in tissue-repair literature but are not interchangeable.

Which PepDirect blends contain TB-500?

TB-500 is a component of GLOW (with GHK-Cu and BPC-157), KLOW (with GHK-Cu, BPC-157 and KPV) and Wolverine (with BPC-157).

Is TB-500 intended for human use?

No. PepDirect supplies TB-500 strictly as a laboratory research material. It is not marketed as a medicine, food supplement or product for human or veterinary use.

↳ Research overview

What Is TB-500?

TB-500 is the common research name for an acetylated 7-amino-acid peptide fragment corresponding to residues 17–23 of thymosin beta-4. It is chemically distinct from full-length thymosin beta-4 and its research literature should be interpreted with that distinction in mind.

This guide covers TB-500's identity as PepDirect supplies it, its relationship to the parent thymosin-beta-4 protein and the shape of the published preclinical evidence.

For laboratory research context only. PepDirect supplies TB-500 as a research material, not for human or veterinary use.

§ Name

What does TB-500 refer to?

'TB-500' is a research-market name used loosely across suppliers and literature. The chemical material referred to under that name is not identical everywhere, some material is labelled TB-500 but is chemically closer to full-length thymosin beta-4, while other material is the shorter acetylated 17–23 fragment. The material must be identified by its chemical description, not assumed from the marketing name alone.

§ Distinction

TB-500 vs full-length thymosin beta-4

PepDirect's TB-500 material is the acetylated thymosin-beta-4 17–23 fragment (N-acetyl-Leu-Lys-Lys-Thr-Glu-Thr-Gln). It is a 7-residue peptide containing the LKKTETQ motif associated with actin-binding research.

Full-length thymosin beta-4 is a distinct 43-residue protein with a different CAS number, different molecular formula and different molecular weight. Research findings for the full-length protein do not automatically apply to the fragment, the two should be treated as separate materials when interpreting evidence.

§ Identity

PepDirect TB-500 chemical identity

Form: acetylated thymosin-beta-4 17–23 fragment (N-acetyl-LKKTETQ)
CAS Number: 885340-08-9
Molecular formula: C38H68N10O14
Molecular weight: ~889.01 g/mol
Sequence: N-acetyl-Leu-Lys-Lys-Thr-Glu-Thr-Gln (7 amino acids)

Lot-specific identity and purity information for a supplied batch should always be verified against the printed lot number and its corresponding Certificate of Analysis.

§ Research themes

Research context

Actin-related cellular processes, the LKKTETQ motif is the actin-binding region identified in thymosin-beta-4 research.
Cell migration and cytoskeletal signalling in preclinical / in-vitro models.
Tissue-repair experimental models involving thymosin-beta-4-related peptides.

When interpreting TB-500 evidence, distinguish (1) research using full-length thymosin beta-4, (2) research using defined shorter fragments and (3) research on the exact acetylated 17–23 fragment. These evidence categories are not interchangeable.

§ TB-500 vs BPC-157

TB-500 and BPC-157 are distinct research peptides

TB-500 is often paired with BPC-157 in tissue-repair research literature and in multi-component research blends. That pairing reflects a shared research theme, not a shared chemical identity. The two peptides are structurally unrelated with different parent proteins and separate published evidence bases.

§ In blends

TB-500 in PepDirect blends

TB-500 is a component of three PepDirect research blends: GLOW (GHK-Cu · BPC-157 · TB-500), KLOW (GHK-Cu · BPC-157 · TB-500 · KPV) and Wolverine (BPC-157 · TB-500).

Research findings involving TB-500 alone should not be interpreted as evidence for the combined blend behaviour of GLOW, KLOW or Wolverine. Blend-level conclusions require research on the specific combined preparation.

§ Research product

View the TB-500 research product

TB-500 is supplied by PepDirect as a lyophilised research material with lot-specific documentation.

View TB-500 Research Peptide →

§ References

Selected research references

TB-500 (acetylated Tβ4 17–23 fragment) · CAS 885340-08-9 identity recordFDA GSRS / precisionFDA
Thymosin β4 (full-length), actin-sequestering research reviewPubMed · Goldstein et al.
Thymosin β4 fragments and actin-binding researchPubMed · Van Troys et al.

§ FAQ

Frequently asked questions

What is TB-500?: TB-500 is a research-market name most commonly used for the acetylated 7-amino-acid peptide fragment corresponding to residues 17–23 of thymosin beta-4. It contains the LKKTETQ actin-binding motif.
Is TB-500 the same as thymosin beta-4?: No. Full-length thymosin beta-4 is a 43-residue protein. TB-500 (as PepDirect supplies it) is the 7-residue acetylated fragment. They are chemically distinct and their research evidence bases should not be conflated.
What TB-500 identity does PepDirect supply?: PepDirect's TB-500 is the acetylated Tβ4 17–23 fragment (N-acetyl-LKKTETQ), CAS 885340-08-9, molecular formula C38H68N10O14, molecular weight ~889.0 g/mol. Lot-specific identity is documented in the corresponding COA.
Is TB-500 the same as BPC-157?: No. TB-500 and BPC-157 are distinct research peptides with different sequences, different parent proteins and different published research histories. They are frequently paired in tissue-repair literature but are not interchangeable.
Which PepDirect blends contain TB-500?: TB-500 is a component of GLOW (with GHK-Cu and BPC-157), KLOW (with GHK-Cu, BPC-157 and KPV) and Wolverine (with BPC-157).
Is TB-500 intended for human use?: No. PepDirect supplies TB-500 strictly as a laboratory research material. It is not marketed as a medicine, food supplement or product for human or veterinary use.

§ Related