Peptide Database
86 therapeutic peptides with research summaries, clinical findings, and regulatory status.
Thymalin
A peptide bioregulator originally extracted from bovine thymus gland, consisting of a mixture of polypeptides that modulate immune function. Thymalin restores T-cell mediated immunity by promoting T-lymphocyte maturation and differentiation in the thymus. It also normalizes the ratio of T-helper to T-suppressor cells and enhances phagocytic activity of neutrophils and macrophages.
LL-37
The only human cathelicidin antimicrobial peptide, a 37-amino acid cationic peptide cleaved from the precursor protein hCAP18. LL-37 disrupts microbial membranes through electrostatic interactions and exerts broad-spectrum activity against bacteria, fungi, and enveloped viruses. Beyond direct antimicrobial effects, it modulates innate immunity by recruiting immune cells, promoting angiogenesis, and regulating inflammatory cytokine release.
VIP (Vasoactive Intestinal Peptide)
A 28-amino acid neuropeptide widely distributed in the central and peripheral nervous systems and immune cells. VIP acts through VPAC1 and VPAC2 receptors to produce potent anti-inflammatory effects by inhibiting the production of pro-inflammatory cytokines (TNF-alpha, IL-6, IL-12) and promoting regulatory T-cell differentiation. It also functions as a vasodilator, bronchodilator, and neuromodulator.
Thymosin Alpha 1 (Zadaxin)
A 28-amino acid peptide originally isolated from thymic tissue (thymosin fraction 5) that serves as a potent immunomodulator. Thymosin alpha 1 enhances T-cell maturation, dendritic cell function, and antibody responses by activating Toll-like receptors (TLR2, TLR9) on innate immune cells. It promotes Th1 immune responses and augments vaccine efficacy while modulating inflammatory cytokine production.
Thymopentin (TP-5)
A synthetic pentapeptide (Arg-Lys-Asp-Val-Tyr) corresponding to residues 32-36 of thymopoietin, a thymic hormone involved in T-cell differentiation. Thymopentin stimulates early T-cell precursor differentiation and modulates mature T-cell function by enhancing IL-2 production and expression of T-cell surface markers. It partially restores immune function in immunocompromised states without the risks of whole thymic extracts.
Thymulin
A zinc-containing nonapeptide (facteur thymique serique) produced exclusively by thymic epithelial cells. Thymulin requires zinc for biological activity and promotes T-lymphocyte differentiation, maturation, and function. Circulating thymulin levels decline progressively with age in parallel with thymic involution, and zinc deficiency independently impairs thymulin activity, linking nutritional status to immune competence.
KPV
A C-terminal tripeptide fragment (Lys-Pro-Val) of alpha-melanocyte-stimulating hormone (alpha-MSH) that retains potent anti-inflammatory activity without melanogenic effects. KPV inhibits NF-kB nuclear translocation and reduces production of pro-inflammatory cytokines including TNF-alpha, IL-1beta, and IL-6. It penetrates cell membranes and directly interacts with inflammatory signaling cascades, making it effective topically and orally for mucosal inflammation.
Icatibant (Firazyr)
A synthetic decapeptide bradykinin B2 receptor antagonist containing five non-natural amino acids for enhanced stability and receptor selectivity. Icatibant competitively blocks bradykinin, the primary mediator of swelling in hereditary angioedema (HAE) caused by C1 esterase inhibitor deficiency. By preventing bradykinin-induced vasodilation and increased vascular permeability, it rapidly reverses mucosal and subcutaneous edema.