# KPV: research overview — Immune & Thymic research peptides > A literature summary of KPV (Lys-Pro-Val), the anti-inflammatory C-terminal tripeptide of alpha-MSH, studied in models of gut inflammation. Covers PepT1 uptake, NF-kB suppression, targeted delivery, and the preclinical-only evidence base. Three amino acids carrying the anti-inflammatory action of a melanocortin hormone — without its pigment effect. Studied most in inflamed gut. ## The short version KPV is one of the smallest peptides in the research literature — just three amino acids: lysine, proline, valine. It is the C-terminal tail (residues 11-13) of alpha-melanocyte-stimulating hormone, or alpha-MSH. What makes it interesting scientifically is that this short fragment retains the parent hormone's potent anti-inflammatory activity while shedding its melanogenic (skin-darkening) action — making it a cleaner research tool for studying inflammation without the confound of pigment biology [12]. In practical terms, KPV dampens the NF-kB and MAP-kinase signaling cascades that drive inflammation, reducing the output of pro-inflammatory cytokines like IL-1beta and TNF-alpha [10]. In the gut specifically, it exploits a clever biological fact: the di/tripeptide transporter PepT1 that carries it directly into intestinal epithelial cells is *upregulated* in inflamed tissue — so the more inflamed the gut, the better the delivery route [10]. The essential caveat: the entire efficacy literature for KPV is preclinical. There are no published human clinical trials. Its evidence base is in vitro cell work and murine colitis models. KPV is not an approved drug or dietary supplement in any jurisdiction, and this page lists no human dose. ## What it is KPV is the linear tripeptide L-lysyl-L-prolyl-L-valine, corresponding to residues 11-13 — the C-terminal sequence — of alpha-melanocyte-stimulating hormone. Its molecular formula is C16H30N4O4. In the literature you will also see it written as alpha-MSH(11-13) or Lys-Pro-Val. Its defining property in the research record is precisely what it *lacks* compared to the full hormone: alpha-MSH exerts broad anti-inflammatory effects but also activates melanocortin receptors (including MC1R) responsible for pigmentation. KPV retains the anti-inflammatory signal through an MC1R-independent route while being without the melanogenic action [11][12]. It is unrelated to melanotan compounds, which are full or partial melanocortin agonists studied specifically for pigmentation — a distinction the literature is careful to maintain. KPV is a research peptide with no approved drug or supplement status in any major jurisdiction. It is sold by chemical suppliers for laboratory research use only. ## How it works KPV suppresses inflammation through two converging mechanisms. **NF-kB and MAP-kinase suppression.** Inside intestinal epithelial cells and immune cells, KPV inhibits the activation of NF-kB — a master transcriptional regulator of pro-inflammatory gene expression — and simultaneously dampens MAP-kinase signaling pathways. The downstream result is reduced secretion of pro-inflammatory cytokines, including IL-1beta and TNF-alpha [10]. At nanomolar concentrations, this suppression is measurable in human intestinal epithelial cell lines (Caco2-BBE and HT29-Cl.19A) and Jurkat T cells [10]. **PepT1-mediated intestinal uptake.** KPV is taken up directly into intestinal epithelial cells via PepT1 (the SLC15A1 di/tripeptide transporter), bypassing the need for a receptor on the luminal surface. PepT1 is physiologically expressed in the intestine to absorb dietary di- and tripeptides, and its expression is markedly upregulated in inflamed intestinal tissue — creating a situation where diseased gut is actually a better target tissue for oral KPV delivery than healthy gut [10]. This is part of why targeted oral delivery formulations have become a focus of recent KPV research. **MC1R independence.** In mouse colitis models, KPV reduced inflammation even in MC1R-deficient mice, confirming that its anti-inflammatory action does not depend on the classic melanocortin receptor — a mechanism distinct from alpha-MSH's receptor pharmacology [11]. ## What the research shows **Mechanism in cells and mice.** The foundational study by Dalmasso and colleagues (2008) demonstrated PepT1-mediated KPV uptake into human intestinal epithelial cell lines, with nanomolar KPV inhibiting NF-kB and MAP-kinase activation and reducing pro-inflammatory cytokine secretion. Orally administered KPV reduced the severity of both DSS-induced and TNBS-induced colitis in C57BL/6 mice [10]. **MC1R-independent colitis recovery.** Kannengiesser and colleagues (2008) showed that the melanocortin-derived tripeptide KPV reduced colonic inflammation in DSS- and adoptive-transfer colitis models — producing earlier recovery, stronger regain of body weight, reduced colonic inflammatory infiltrate, and lower myeloperoxidase activity — with the effect retained in MC1R-deficient animals. This established the independence of KPV's anti-inflammatory mechanism from the canonical melanocortin-receptor pathway [11]. **Targeted oral delivery.** Because free KPV is a small, peptidase-labile tripeptide that would be degraded before reaching the colon in most formulations, much of the recent KPV literature is formulation science. In 2017, Xiao and colleagues showed that orally administered hyaluronic-acid-functionalized nanoparticles carrying KPV, embedded in a chitosan/alginate hydrogel, delivered the peptide to inflamed colon tissue and reduced colitis severity more effectively than non-targeted formulations, downregulating TNF-alpha and accelerating mucosal healing in mice [9]. **Combination nanodrug.** A 2024 study constructed a PepT1-targeted nanodrug co-assembling KPV with the immunosuppressant FK506. In C57 mice with acute and chronic DSS-induced colitis, the combination nanoparticles outperformed either agent alone, restoring tight-junction proteins and lowering inflammatory cytokines [8]. **Breadth review.** A comprehensive 2008 review of alpha-MSH and related tripeptides documented protective effects of KPV and related fragments across fever, dermatitis, vasculitis, fibrosis, ocular, gastrointestinal, airway, arthritic and organ-injury models, explicitly delineating KPV as the anti-inflammatory alternative to alpha-MSH because it preserves anti-inflammatory effect while lacking pigmentary action [12]. ## Reported effects, cautions & safety KPV has no compiled community anecdote record in this desk's source material — which reflects its very limited human footprint. It is sold as a laboratory research chemical and is not widely used in self-administered human contexts in the way that some other research peptides are. The cautions below are drawn from the published literature. - *No human trials.* There are no published human clinical trials of KPV. The entire efficacy literature is in vitro and animal, chiefly murine colitis. Human dosing, efficacy and safety are entirely unestablished [10]. - *Peptide fragility and absence of human pharmacokinetics.* Free KPV is a small, peptidase-labile tripeptide; without a delivery vehicle it would be degraded before reaching target tissue. There are no validated human pharmacokinetic data — no absorption, distribution, metabolism or excretion profile in any human context [9]. - *Marketing outruns evidence.* KPV is promoted online for gut health, skin, and general anti-inflammatory use. That marketing runs well ahead of evidence that is mechanistic and preclinical, not clinical. - *Not a tanning or pigmentation agent.* Although KPV derives from alpha-MSH, it should be clearly distinguished from melanocortin agonists studied for pigmentation or tanning. KPV's defining characteristic in the research record is anti-inflammatory action *without* pigmentary effect [12]. - *No approved drug or supplement status.* KPV is not approved by the FDA or any other major regulator for human use. It is available only as a research chemical for laboratory use. - *WADA status.* No KPV-specific WADA classification is established; as a non-approved peptide it should be treated cautiously in any sport context. ## Where it fits in immune research On this desk, KPV occupies a distinct and complementary role to [Thymosin Alpha-1](/thymosin-alpha-1). Where Thymosin Alpha-1 is studied for *restoring* immune competence — reconstituting T-cell populations, reversing T-cell exhaustion, priming Th1 responses — KPV is studied for *calming* the inflammatory arm of the immune response when it becomes destructive [10][12]. Thymosin Alpha-1 has four decades of clinical trials and international drug approval; KPV is entirely preclinical. Together they illustrate the two ends of immune modulation that researchers in this field keep returning to: too little immunity and too much inflammation are both problems, and different peptides address different sides. See how the two compare on the [comparison page](/compare). ![KPV tripeptide interaction with PepT1 transporter in inflamed intestinal epithelium — cold sapphire palette](/images/kpv.webp) --- An independent literature digest of peer-reviewed immunology research — not a clinic, not a vendor, not a prescription.