Peptides studied for modulating immune activity and supporting the integrity of the intestinal barrier — from thymic immune peptides to antimicrobial and tight-junction compounds.
Start with the fundamentals before comparing compounds.
7 compounds in this research area. Each links to a full profile, dosing chart, and sourcing.
Immunomodulatory 28-amino-acid peptide
An immune-modulating 28-amino-acid peptide, marketed as Zadaxin in a number of countries. It is among the more clinically studied immune peptides, though it is not FDA-approved in the United States.
Cathelicidin-derived antimicrobial peptide
The only human cathelicidin antimicrobial peptide, studied for direct antimicrobial activity as well as roles in inflammation and wound healing. Human therapeutic use is investigational.
Alpha-MSH-derived tripeptide
A tripeptide fragment (Lys-Pro-Val) derived from the C-terminus of alpha-MSH, studied for anti-inflammatory effects, particularly in models of gut inflammation.
Synthetic octapeptide (tight-junction regulator)
An orally administered octapeptide studied as a 'tight-junction regulator' for reducing intestinal permeability, most notably in celiac-disease research.
28-amino-acid vasoactive and immunomodulatory neuropeptide (secretin/glucagon family)
Vasoactive intestinal peptide (VIP) is a 28-amino-acid neuropeptide with broad roles in vasodilation, smooth-muscle relaxation, secretion, and immune regulation. A synthetic form, aviptadil, has been investigated clinically for respiratory and pulmonary conditions. Some research communities use intranasal VIP; the systemic half-life is very short.
Zinc-dependent nonapeptide thymic hormone
Thymulin is a nine-amino-acid thymic peptide hormone that requires bound zinc for biological activity. Secreted by thymic epithelial cells, it participates in T-cell differentiation and immune regulation and has been studied for immunomodulation, inflammation, and (in analog form) pain and neuroinflammation. It is investigational.
Thymic peptide bioregulator (polypeptide fraction)
Thymalin is a peptide fraction extracted from thymus tissue and used in Russian clinical research as an immunomodulator intended to restore T-cell balance in aging and illness. It is used as a drug in Russia but is not FDA-approved, and most evidence comes from Russian-language literature.
Educational summary only. Dosing figures describe how these compounds appear in the research literature and research-community references — they are not a personal treatment plan or a recommendation for human use. For laboratory research use only.
