Immune Modulation Research Peptides
Overview
21 research peptides demonstrate immune modulation properties. This collection covers their mechanisms, evidence base, and research applications.
LL-37
Preclinical | Antimicrobial / Immune
LL-37 is the only human cathelicidin antimicrobial peptide, a 37-amino-acid cationic peptide (sequence: LLGDFFRKSKEKIGKEFKRIVQRIKDFLRNLVPRTES) with broad-spectrum antimicrobial activity against Gram-positive and Gram-negative bacteria, fungi,...
Mechanism: LL-37 (C120H232N42O38) carries a net positive charge (+6) that binds negatively charged bacterial membranes, creating transmembrane pores causing cell lysis. It also has anti-biofilm activity.
Epithalon
Preclinical | Anti-Aging / Telomere
Epithalon is a synthetic tetrapeptide (Ala-Glu-Asp-Gly, MW ~390 g/mol) developed by Russian gerontologist Vladimir Khavinson at the St. Petersburg Institute of Bioregulation and Gerontology.
Mechanism: Epithalon (C14H22N4O9, MW ~390 daltons) activates telomerase, particularly the catalytic subunit TERT (telomerase reverse transcriptase), extending telomeres at chromosome ends.
Thymosin Alpha-1
Phase I–II Clinical Trials | Immune Modulator
Thymosin alpha-1 (Ta1) is a clinically proven, 28-amino-acid peptide (MW ~3,108 g/mol, Ac-Ser-Asp-Ala-Ala-Val-Asp-Thr-Ser-Ser-Glu-Ile-Thr-Thr-Lys-Asp-Leu-Lys-Glu-Lys-Lys-Glu-Val-Val-Glu-Glu-Ala-Glu-Asn-OH) naturally produced by the thymus gland.
Mechanism: Ta1 (C129H215N33O55) activates Toll-like Receptors TLR2 and TLR9 on immune cells, triggering the MyD88 and NF-kB signaling pathways to put the immune system on alert without destructive inflammation.
Selank
Preclinical | Nootropic / Anxiolytic
Selank is a synthetic heptapeptide (Thr-Lys-Pro-Arg-Pro-Gly-Pro, MW ~751.89 g/mol) developed at the Institute of Molecular Genetics of the Russian Academy of Sciences.
Mechanism: Selank (C33H57N11O9, half-life ~2-10 minutes) crosses the blood-brain barrier. It acts as a positive allosteric modulator of GABA-A receptors, increasing GABA binding affinity without directly...
Larazotide
Phase III / NDA Filed | Healing & Recovery
Larazotide (AT-1001) is a synthetic 8-amino acid peptide that acts as a tight junction regulator. It is being developed as an oral adjunct therapy for celiac disease, designed to reduce intestinal permeability ("leaky gut") triggered by gluten...
Mechanism: Larazotide acts as a zonulin antagonist, blocking the zonulin pathway that opens tight junctions in the intestinal epithelium.
Thymulin
Early Clinical / Preclinical | Immune Modulator
Thymulin (FTS) is a 9-amino-acid zinc metallopeptide (sequence: pyroGlu-Ala-Lys-Ser-Gln-Gly-Gly-Ser-Asn, MW ~858 g/mol) secreted exclusively by thymic epithelial cells.
Mechanism: Thymulin binds zinc in a 1:1 stoichiometric ratio, which is required for its active conformation and receptor binding.
Octreotide
FDA Approved | Endocrine / Somatostatin Analog
Octreotide is a synthetic 8-amino-acid cyclic peptide (MW ~1019.2 g/mol) that mimics the pharmacological actions of natural somatostatin but with a significantly longer half-life.
Mechanism: Octreotide binds preferentially to somatostatin receptor subtypes 2 (SSTR2) and 5 (SSTR5), with moderate affinity for SSTR3.
Lanreotide
FDA Approved | Endocrine / Somatostatin Analog
Lanreotide is a synthetic 8-amino-acid cyclic somatostatin analog (MW ~1096.3 g/mol) available as a long-acting deep subcutaneous depot injection (Somatuline Depot/Autogel).
Mechanism: Lanreotide binds with high affinity to somatostatin receptor subtypes SSTR2 and SSTR5, and with moderate affinity to SSTR3.
Romiplostim
FDA Approved | Hematology / TPO Agonist
Romiplostim is a peptide-Fc fusion protein (peptibody) with a molecular weight of approximately 59,000 g/mol that acts as a thrombopoietin (TPO) receptor agonist.
Mechanism: Romiplostim is a "peptibody" consisting of two identical single-chain subunits, each containing a human IgG1 Fc domain covalently linked to a peptide chain containing two TPO receptor-binding domains.
Glutathione
Meaningful Human Clinical Data | Antioxidant / Detoxification
Glutathione is a tripeptide (Glu-Cys-Gly, MW ~307.3 g/mol) and the most abundant intracellular antioxidant in mammalian cells. It is critical for Phase II detoxification, free radical scavenging, immune function, and cellular redox homeostasis.
Mechanism: Glutathione functions as the primary intracellular reducing agent, directly scavenging reactive oxygen species (ROS) and serving as a cofactor for glutathione peroxidase and glutathione-S-transferase...
PNC-27
Animal/Preclinical Only | Cancer Research
PNC-27 is a chimeric peptide (~3,000 g/mol) composed of a p53 protein binding domain fused to a cell-penetrating/membrane-lytic domain.
Mechanism: PNC-27 contains a 12-residue p53 peptide sequence that binds to HDM-2 (MDM-2 in humans), a protein normally found in the nucleus but abnormally expressed on the outer cell membrane of many cancer...
Thymalin
Early Human or Mixed Evidence | Immune / Anti-Aging
Thymalin is a polypeptide complex isolated from calf thymus glands, developed by Vladimir Khavinson and colleagues at the St. Petersburg Institute of Bioregulation and Gerontology.
Mechanism: Thymalin contains short bioregulatory peptides (primarily di- and tripeptides including Glu-Trp) derived from thymic tissue.
Vilon
Animal/Preclinical Only | Immune / Anti-Aging
Vilon (Lys-Glu, KE) is a synthetic dipeptide (MW ~275.3 g/mol) developed by Khavinson as a simplified synthetic version of the active component in thymalin. It is one of the shortest bioregulatory peptides proposed to have immunomodulatory activity.
Mechanism: Vilon (Lys-Glu) is proposed to complement DNA sequences in gene promoter regions controlling immune-related genes, modulating their transcription.
Livagen
Animal/Preclinical Only | Hepatic / Anti-Aging
Livagen (Lys-Glu-Asp-Ala, KEDA) is a synthetic tetrapeptide (MW ~432.5 g/mol) developed by Khavinson as a liver-specific bioregulatory peptide.
Mechanism: Livagen is proposed to penetrate hepatocyte nuclei and interact with specific heterochromatin regions that become condensed (silenced) during aging.
Vesilute
Animal/Preclinical Only | Cardiovascular / Anti-Aging
Vesilute (Lys-Glu-Asp, KED) is a synthetic tripeptide (MW ~390.4 g/mol) from the Khavinson bioregulatory peptide family, developed as a vascular-specific bioregulator.
Mechanism: Vesilute is proposed to modulate gene expression in vascular endothelial and smooth muscle cells, restoring production of nitric oxide synthase, elastin, and other structural/functional proteins that...
Related Research News
Epithalon Research: Telomerase Activation and Longevity Effects
Epithalon, a synthetic tetrapeptide (Ala-Glu-Asp-Gly, AEDG), activates telomerase in human cells, leading to telomere elongation according to studies by Vladimir Khavinson's group. Research also shows lifespan extensions of 6% to 25% in rodents, reduced tumor incidence, and restored melatonin rhythms in aging models. These findings link the peptide to pineal gland function and oxidative stress reduction, though independent replication remains limited.
Anti-Aging Peptides: Epithalon, NAD+, GHK-Cu Research
Research on anti-aging peptides targets cellular aging processes like telomere shortening, mitochondrial decline, and gene expression changes. Compounds such as Epithalon from Khavinson’s group, GHK-Cu with over 4,000 gene interactions documented by Pickart, and NAD+ for sirtuin activation show promise in preclinical models. These peptides support studies on telomerase activation, collagen synthesis, DNA repair, and more, with all compounds verified at ≥98% purity by HPLC and published COAs.