Side-by-side · Research reference
LL-37vsTB-500
Side-by-side comparison across mechanism, dosage, evidence, side effects, administration, and stack synergies. Citations on every claim where available.
AHuman-MechanisticHUMAN-REVIEWED15/35 cited
BPhase 2HUMAN-REVIEWED8/46 cited
LL-37
Cathelicidin · Human AMP
Broad-spectrumAntimicrobial activity
Endogenous · Secreted at inflammation sites
TB-500
Thymosin β4 fragment · Healing
SQ or IM · Multiple sites · 2–3×/week
01Mechanism of Action
Parameter
LL-37
TB-500
Primary target
G-actin (sequestering) + cell-surface integrinsGoldstein 2012
Pathway
hCAP-18 precursor → Proteinase-3 cleavage → LL-37 release → Membrane insertion/disruption
Actin remodelling → cell migration; integrin-linked signaling → angiogenesis; anti-inflammatory cytokine modulationGoldstein 2012Malinda 1999
Downstream effect
Membrane permeabilization, cytokine induction, autophagy, phagosome-lysosome fusion, chemotaxisAhmad 2026Zhang 2026
Accelerated wound healing, endothelial migration, hair follicle regeneration, cardiac repair (preclinical)Goldstein 2012
Feedback intact?
—
Endogenous protein at baseline; supplementation amplifies
Origin
Endogenous human cathelicidin (37-AA fragment, residues 134–170 of hCAP-18)
17-AA active fragment of endogenous 43-AA thymosin β4 (TMSB4X gene)Goldstein 2012
Antibody development
—
—
02Dosage Protocols
Parameter
LL-37
TB-500
Endogenous expression
Constitutive in neutrophils, epithelial tissues
Upregulated during infection and inflammation.Pinheiro 2026
—
Exogenous (experimental)
Dose varies by study; antimalarial ~10–50 μM in vitro
No FDA-approved exogenous formulation.
—
Plasma levels (malaria)
Elevated in infected patients and miceHe 2026
Exogenous administration reduced parasitemia in murine models.He 2026
—
Evidence basis
In vitro, animal models, human observational
Animal-strong + Phase 2 dermal/ocular trialsGoldstein 2012
Standard dose
—
2 mg per injectionGoldstein 2012
Anecdotal community range; clinical Phase 2 trials used 70–840 mcg/kg IV.
Frequency
—
2× per week (loading); then 1× per week (maintenance)
Lower / starter dose
—
1 mg per injection
Duration
—
4–8 weeks loading; longer maintenance for chronic injury
Reconstitution
—
Bacteriostatic water, 1–2 mL per 5 mg vial
Timing
—
Evening or pre-rest preferred (anecdotal)
Half-life
—
~2 hours (estimated; tissue uptake longer)
04Side Effects & Safety
Parameter
LL-37
TB-500
Cytotoxicity (high dose)
Membrane disruption in host cells at supraphysiological concentrations
—
Pro-inflammatory signaling
Can exacerbate inflammation in certain contexts (context-dependent)Pinheiro 2026
—
Theoretical cancer risk
Immunomodulatory roles in tumor microenvironment under investigation
—
Injection site reaction
—
Mild erythema, transient pain
GI symptoms
—
Rare nausea (anecdotal)
Cancer risk
—
Theoretical via angiogenesis pathway
Lethargy / fatigue
—
Reported anecdotally during loading phase
Antibody formation
—
No data (no long-term human trials)
Pregnancy / OB
—
Avoid
Long-term safety
—
Unknown beyond Phase 2
Absolute Contraindications
LL-37
—TB-500
- ·Active malignancy (theoretical angiogenesis concern)
- ·Pregnancy / breastfeeding
Relative Contraindications
LL-37
- ·Active autoimmune disease (theoretical immune dysregulation)
TB-500
- ·Cancer history
- ·Concurrent VEGF inhibitor therapy
05Administration Protocol
Parameter
LL-37
TB-500
1. Natural secretion
LL-37 is constitutively expressed in neutrophils and epithelial cells, cleaved from hCAP-18 by proteinase-3 at sites of infection or inflammation.
Add 1–2 mL bacteriostatic water to 5 mg vial → 2.5–5 mg/mL. Roll gently.
2. Experimental formulations
Synthetic LL-37 and derivatives (e.g., SAMP-12aa) tested in vitro and animal models. Administered via topical, intraperitoneal, or intravenous routes in research settings.
SQ near injury site (preferred), or systemic SQ (abdomen). Rotate sites.
3. Stability considerations
LL-37 is resistant to pepsin degradation at gastric pH. Synthetic short peptides designed to retain this stability while reducing toxicity.Lu 2026
Evening or pre-sleep is most common anecdotal timing.
4. Storage
—
Lyophilised: room temp, light-protected. Reconstituted: refrigerate, ≤30 days.
5. Needle
—
27–31G, 4–8 mm insulin syringe.
06Stack Synergy
LL-37
— no documented stacks
TB-500
+ BPC-157
StrongTB-500 and BPC-157 cover complementary halves of tissue repair: BPC-157 upregulates VEGFR2-driven angiogenesis and fibroblast outgrowth; TB-500 sequesters G-actin to enable endothelial / epithelial migration. The anecdotal canonical "healing stack" — pairs especially well for tendon and ligament injuries.
- TB-500
- 2 mg SQ · 2× per week
- BPC-157
- 250–500 mcg SQ · daily
- Primary benefit
- Combined angiogenesis + cell migration for tendon/ligament/muscle repair