Tissue repair peptides promote healing through angiogenesis, anti-inflammatory signaling, and growth factor modulation. BPC-157 (Body Protection Compound) and Thymosin Beta-4 (TB-500) are the most studied examples - both derived from endogenous human proteins.
BPC-157 is a 15-residue fragment of a gastric juice protein with broad tissue repair activity across tendons, ligaments, muscle, and gut epithelium. TB-500 is the full 43-residue Thymosin Beta-4 with the active heptapeptide LKKTETQ responsible for actin sequestration and cell migration.
Tissue repair is the broadest functional target category in peptide biology, spanning dermal wound closure, tendon and ligament regeneration, mucosal healing, and organ cytoprotection. The dominant research archetypes are Thymosin β-4 (Tβ4) and BPC-157, both of which act upstream of actin dynamics and angiogenesis but through distinct mechanisms. Tβ4 is an endogenous 43-amino-acid peptide expressed in virtually every nucleated cell; BPC-157 is a synthetic 15-mer (GEPPPGKPADDAGLV) derived from the gastric body-protective protein and has no endogenous parent sequence. Neither is FDA-approved for systemic wound healing, and BPC-157 was reclassified by the FDA as a Category 1 substance in February 2026, making it ineligible for compounding under 503A/503B — a regulatory signal that separates it sharply from Tβ4 in the current clinical landscape.
Thymosin β-4 (gene: TMSB4X; 43 aa, 4.96 kDa; no disulfide bonds) sequesters G-actin through its LKKTETSQ heptapeptide core, regulating the G/F-actin equilibrium that controls lamellipodia extension and cell migration. It also activates ILK (integrin-linked kinase), which phosphorylates AKT and promotes endothelial survival and tube formation. The Tβ4 N-terminal tetrapeptide Ac-SDKP is released by prolyl oligopeptidase and has independent anti-inflammatory and anti-fibrotic activity, making Tβ4 a precursor as well as an effector. BPC-157 (sequence: GEPPPGKPADDAGLV) does not bind actin directly; its angiogenic and cytoprotective effects are mediated through upregulation of VEGFR2, FAK/paxillin focal-adhesion signaling, and stabilization of the NO-system. DPP-4 cleaves BPC-157 at the Pro2–Pro3 bond in vitro, though the physiological relevance in vivo remains debated. Other peptides in this category include GHK (Gly-His-Lys), a copper-chelating tripeptide that induces TGF-β1 and MMP-2 remodeling enzymes, and RGD-motif peptides that engage αvβ3/αvβ5 integrins to accelerate epithelial migration.
No tissue-repair peptide is FDA-approved for systemic wound healing as of 2026. RegeneRx holds the most advanced Tβ4 clinical program: RGN-259 (ophthalmic, Phase 3, ARISE-3 for neurotrophic keratopathy, NCT identifier available in trial registry) and RGN-352 (intravenous, Phase 2, ICAP trial for cardiac repair post-MI). Both met primary endpoints in earlier phases. BPC-157 human trial data is sparse: NCT02637284 (inflammatory bowel disease, completed, results not published as of 2025) and NCT07437547 (ongoing). The animal literature is extensive but heterogeneous in route, dose, and model — human translation remains unestablished. For peptide research, the tractable recipes are: Ala2-BPC-157 (substituted analogue with improved DPP-4 resistance), native Tβ4 (full 43-mer, predicted structure available via AlphaFold2/Boltz-1), Ac-SDKP (N-terminal fragment, 4 aa, minimal synthesis complexity), and GHK-Cu (copper chelate, commercial availability high, human skin data exists).
Groups peptides by what they do, not what they bind. There's no PDB or UniProt — the target is a function, not a molecule. For receptor-level structure, open a molecular target like GHSR.
GEPPPGKPADDAGLV · 15 aa · @peptidemodel
| # | id | title | author | status | refs | ipSAE_d0chn | ♥ |
|---|---|---|---|---|---|---|---|
| 1 | pep-00001 | BPC-157: gut-healing research peptide (Body Protection Compound 157) | pe@peptidemodel | 2 | — | 0 | |
| 2 | pep-00013 | TB-500 (Thymosin Beta-4): experimental tissue-repair peptide | pe@peptidemodel | 2 | — | 0 | |
| 3 | pep-10783 | Cell-grip blocker related to Cilengitide (cycloRGDFC) | pe@peptidemodel | 8 | — | 0 | |
| 4 | pep-10784 | Tissue-repair signaling fragment (RGDS) | pe@peptidemodel | 7 | — | 0 | |
| 5 | pep-10900 | Larazotide Acetate: gut-lining sealer for celiac disease (AT-1001) | pe@peptidemodel | 2 | — | 0 |
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