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Immune Modulator

LL-37

Also known as: Cathelicidin

LL-37 is the only human cathelicidin antimicrobial peptide — a 37-amino-acid peptide (starting with two leucines) cleaved from the hCAP-18 precursor. It has broad-spectrum antimicrobial activity and immunomodulatory roles, but is also implicated in the pathogenesis of autoimmune and inflammatory skin diseases including psoriasis, rosacea, and lupus. Not FDA-approved; research-use only.

Real-time market data

Pricing for LL-37

Live vendor pricing, normalized to $/mg so sizes compare fairly — fused with each seller's Merit trust score and latest independent COA purity. Prices refresh daily.

Average price

$11.84/mg

range $1.96–$29.00/mg

Sellers

43

from $0.00

45-day trend

+4.2%

vs 45-day avg $/mg

35 of 43 sellers have a current price· 6 stale listings hidden (not seen in 7 days)

Prices observed from public storefronts (last 24h), normalized to $/mg. "Evidence" is Merit's 0–100 Merit Score, derived only from observable verification evidence (methodology on /about); "Purity" is the latest independent COA. Some buy links are affiliate links — Merit may earn a commission at no extra cost to you, and where a vendor offers one, the code shown gets you a discount at their checkout. Affiliate status never affects price data, ranking, or the Merit Score (full policy on /disclosure). Research use only.

Independent evidence

COAs for LL-37

42 third-party tests across 12 vendors. Each card links to the full report.

All 42 COAs for LL-37 →
Measured purity 91.1%–99.9% across 33 COAs
Measured purity over time
Aggregated · 3rd-party listing
99.60 %
Jun 2026
ILS Labs Strong

For

LL-37

by Ion Peptide· batch L375-06092026

✓ Vendor-published
99.83 %
Jun 2026
ILS Laboratories

For

LL-37

by Ion Peptide· batch L375-06092026

COA on file
Aggregated · 3rd-party listing
99.64 %
May 2026
Janoshik Analytical Limited · HPLC

For

LL-37

by Verified Peptides· batch LL05260305C

Aggregated · 3rd-party listing
99.64 %
May 2026
Janoshik Analytical Limited

For

LL-37

by Verified Peptides

Aggregated · 3rd-party listing
94.08 %
May 2026
Janoshik Analytical Limited

For

LL-37

by Verified Peptides· batch LL025602005C

Aggregated · 3rd-party listing
91.08 %
May 2026
Freedom Diagnostics Moderate

For

LL-37

by Real Peptides· batch Black Cap

Aggregated · 3rd-party listing
99.94 %
Mar 2026
Kovera Labs

For

LL-37

by Ion Peptide· batch LL375-03232026

✓ Vendor-published
99.94 %
Mar 2026
Kovera Labs

For

LL-37

by Ion Peptide· batch LL375-03232026

COA on file
Aggregated · 3rd-party listing
99.50 %
Feb 2026
Janoshik Analytical Limited

For

LL-37

by EZ Peptides· batch EZP-LL371002172026-01

✓ Vendor-published
99.50 %
Feb 2026
Janoshik Analytical Limited

For

LL-37

by EZ Peptides· batch EZP-LL37100217-2026-01

COA on file
Aggregated · 3rd-party listing
99.47 %
Feb 2026
Vanguard Laboratory Strong

For

LL-37

by Peptidology· batch 1669

✓ Vendor-published
99.04 %
Jan 2026
Janoshik Analytical Limited

For

LL-37

by Ruo Bio

COA on file
Aggregated · 3rd-party listing
99.93 %
Jan 2026
Freedom Diagnostics Moderate · HPLC

For

LL-37

by Simple Peptide· batch L1-05-01162026-J

Aggregated · 3rd-party listing
99.93 %
Jan 2026
Freedom Diagnostics Moderate · HPLC

For

LL-37

by Simple Peptide· batch LL10-37011220236-J

Aggregated · 3rd-party listing
99.70 %
Jan 2026
Freedom Diagnostics Moderate · HPLC

For

LL-37

by MedGe Peptides· batch LL375LT12

Aggregated · 3rd-party listing
99.70 %
Jan 2026
Freedom Diagnostics Moderate · HPLC

For

LL-37

by MedGe Peptides· batch LL375LT12

Aggregated · 3rd-party listing
99.84 %
Jan 2026
Freedom Diagnostics Moderate · HPLC

For

LL-37

by Simple Peptide· batch LL37L2092025-J

Aggregated · 3rd-party listing
99.82 %
Jan 2026
Chromate Moderate

For

LL-37

by Orbitrex Peptides· batch LL5126

Aggregated · 3rd-party listing
99.82 %
Dec 2025
Chromate Moderate

For

LL-37

by Orbitrex Peptides

Aggregated · 3rd-party listing
99.83 %
Dec 2025
BioRegen Moderate

For

LL-37

by Real Peptides

Aggregated · 3rd-party listing
99.82 %
Oct 2025
Freedom Diagnostics Moderate

For

LL-37

by Kimera Chems· batch KC-L37-BLU1

Aggregated · 3rd-party listing
99.65 %
Oct 2025
Chromate Moderate · HPLC

For

LL-37

by Mile High Compounds· batch LL3-005-MH-01

✓ Vendor-published
99.65 %
Oct 2025
Chromate Moderate

For

LL-37

by Mile High Compounds· batch LL3-005-MH-01

COA on file
Aggregated · 3rd-party listing
99.80 %
Oct 2025
MDx BioAnalytical Laboratory Strong · HPLC

For

LL-37

by BioLongevity Labs· batch 251549

Research depth

20 citations indexed for LL-37

All research on LL-37 →

review · 2026

LL-37: Biological Mechanisms and Emerging Therapeutic Applications in Intestinal Disease

Human cathelicidin peptide LL-37 is encoded by the CAMP gene and plays a key role in innate immunity. It maintains intestinal homeostasis through antibacterial, immunomodulation, and tissue repair functions.

Study · 2026

LL-37 and citrullinated-LL-37 enhances oxylipins: citrullination attenuates LL-37-mediated COX-2-dependent chemokine response in human bronchial epithelial cells

BACKGROUND: During airway inflammation, chemokines, oxylipins (bioactive lipids) and cationic host defence peptides (CHDP) are enhanced in the lungs. However, the interplay of these molecules in the process of airway inflammation is not fully resolved.

review · 2026

β-Amyloid (Aβ) and Human Cathelicidin LL-37: Two Sides of the Same Coin?

Study · 2026

A degradable hydrogel scaffold incorporating the LL-37 for gingival soft tissue regeneration

Gingival recession exposes the roots, leads to dentin hypersensitivity, and heightens the progression of periodontitis, and poses a threat to oral health and appearance. Conventional treatment uses autogenous palatal grafts, requiring a second surgical site and adding patient discomfort.

review · 2026

β-Amyloid (Aβ) and Human Cathelicidin LL-37: Two Sides of the Same Coin?

Physiologically produced circulating β-amyloid (Aβ) exerts critical physiological functions. Although Aβ is a key player in Alzheimer's disease (AD), it may initially be beneficial at the onset of infection.

Study · 2026

[Evaluation of Serum LL-37 Levels in Patients with Brucellosis and Their Relationship with Clinical Course]

This study aimed to determine the serum levels of the LL-37 molecule, associated with the pathophysiology of Brucellosis, in patients diagnosed with Brucellosis and to investigate the relationship between these levels and the clinical course of the disease.