LL-37 (Cathelicidin) vs Thymosin Alpha-1

Side-by-side comparison of mechanisms, dosing, interactions, and stacking potential.

✅ Stacking Partners — These compounds are commonly used together and may have synergistic effects.
LL-37 (Cathelicidin)Thymosin Alpha-1
CategoryPeptidesGrowth Factors
Standard DoseResearch indicates 50-100 mcg daily via subcutaneous injection for immune support.Research indicates 1.6 mg administered twice weekly via subcutaneous injection.
TimingMorning administration preferred for immune support. Topical application directly to wound sites.Morning administration preferred. No food timing restrictions.
Cycle Duration4-8 week cycles. Short-term use preferred due to limited long-term safety data.8-12 week cycles, with periodic breaks. Some protocols use continuous low-dose maintenance.
Evidence Levelanimal_plus_anecdotalstrong_human

Mechanism

LL-37 is a 37-residue amphipathic helical antimicrobial peptide, the only human cathelicidin, that kills bacteria by forming tetrameric channels that perforate cytoplasmic membranes. Beyond direct antimicrobial activity, it modulates innate immunity through formyl-peptide receptor 2 (FPR2), induces chemotaxis of neutrophils and monocytes, upregulates CXCR4 and IL-8, and neutralizes bacterial endotoxins (LPS). It also promotes wound healing through keratinocyte migration and angiogenesis.

Standard Dosing

Research indicates 50-100 mcg daily via subcutaneous injection for immune support.

Timing

Morning administration preferred for immune support. Topical application directly to wound sites.

Cycle Duration

4-8 week cycles. Short-term use preferred due to limited long-term safety data.

Side Effects

  • Injection site pain and redness
  • Localized inflammation
  • Potential mast cell activation

Contraindications

  • Active autoimmune conditions (particularly lupus — LL-37 is implicated in SLE pathophysiology)
  • Pregnancy and breastfeeding
  • Psoriasis (may exacerbate)

Best Stacking Partners

KPVThymosin Alpha-1BPC-157
B

Thymosin Alpha-1

Growth Factors

Mechanism

Thymosin Alpha-1 is a 28-amino acid peptide naturally produced by the thymus that acts as a pleiotropic immune modulator through Toll-like receptors (TLR2, TLR3, TLR4, TLR7, TLR9) on myeloid and plasmacytoid dendritic cells. It activates downstream IRF3, NF-kB, p38MAPK, and MyD88 signaling pathways to promote cytokine production. It modulates TNF-alpha, IFN-gamma, and IL-2 in CD4+ and CD8+ T lymphocytes by upregulating CD40/CD40L and downregulating PD-L1/PD-1 expression, enhancing both innate and adaptive immunity.

Standard Dosing

Research indicates 1.6 mg administered twice weekly via subcutaneous injection.

Timing

Morning administration preferred. No food timing restrictions.

Cycle Duration

8-12 week cycles, with periodic breaks. Some protocols use continuous low-dose maintenance.

Side Effects

  • Injection site reactions
  • Mild flu-like symptoms
  • Fatigue
  • Muscle aches (rare)

Contraindications

  • Organ transplant recipients on immunosuppression
  • Active autoimmune diseases
  • Pregnancy and breastfeeding
  • Autoimmune conditions require careful supervision

Best Stacking Partners

BPC-157GHK-CuSelank

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