Now reading Entry 044 / 102 Last revised Jan 28, 2026 28 sources 1 comparisons Methodology →
A specimen of the Immune drawer Drawer F · Immune

Lactoferricin

Research Only

An antimicrobial peptide derived from lactoferrin, a protein found in milk and other secretions. Shows broad-spectrum antimicrobial activity in laboratory studies. Research focuses on potential applications in infectious disease, food safety, and cancer. Primarily studied preclinically with very limited human clinical data. Not approved as a therapeutic by any regulatory agency.

LFcinB · Lactoferricin B · LfcinB · LFcin

Research evidence
Low

Mostly preclinical · 2 human studies

Preclinical
93%
Clinical
7%

Based on 28 cited sources

Evidence Score46/100
Early / limited
Research Depth18/100
Mechanism77/100
Plausibility74/100
Global Coverage64/100
Community Experience7/100
EffectivenessNot Established

Demonstrated effect magnitude — not a recommendation or safety claim.

Research Depth 18: all evidence is preclinical — in-vitro plus animal models (Kondori 21075607 murine Candida, Hao 28287172 endotoxemic mice), zero human therapeutic data (1A=6 animal/no-human, 1B=2 no RCTs, 1C=0 human N~0, 1D=2 indirect), offset by a substantial independently-replicated preclinical program (1E=8). Mechanism 77: membrane-target binding with functional confirmation and fragment SAR (Bellamy 8300449, Ulvatne 11248238 depolarization; 2A=30), most of the antimicrobial and apoptotic chains characterized (2B=22, Mader 15827335 ROS->caspase-2->mitochondrial->caspase-9/3), monotonic dose-response across in-vitro + in-vivo models (2C=16, MICs 0.63-50 ug/mL; Hao 10/15 mg/kg), in-vivo mammalian confirmation (2D=9). Plausibility 74: mechanism->surrogate established but surrogate->human benefit inferred (3A=24), fully coherent cationic-AMP biology (3B=24), multiple same-class agents LL-37/defensins/polymyxin B reliably membrane-disruptive (3C=18), moderately broad antibacterial/antifungal/anticancer/immune claims (3D=8). Global Coverage 64: robustly reproduced across independent groups in Japan, Norway, Canada, China, Sweden (4A=28, 4B=18), 20-100+ diverse studies (4C=18), but no regulator has registered it as a therapeutic (4D=0). Community Experience 7: dossier records no meaningful real-world use or reports (5A=3, 5B=2, 5C=0, 5D=2). Effectiveness not-established: no quantified human efficacy estimate and no meaningful community effect signal.

Scored June 2026 How we rate →
!
Evidence Level
low
Not approved for human use by any regulatory agency
Limited human clinical trial data
Consult a healthcare provider before use
Not FDA Approved WADA Prohibited
Identity
SCALE · 1:1 N-TERMINUS C-TERMINUS 25 AA · 3,126 Da
Also Known As
LFcinB • Lactoferricin B • LfcinB • LFcin
Class
Cationic antimicrobial peptide
Length
25 amino acids
Mol. weight
3,126 Da
Sequence
FKCRRWQWRMKKLGAPSITCVRRAF
Molecular Structure
F
K
C
R
R
W
Q
W
R
M
K
K
L
G
A
P
S
I
T
C
V
R
R
A
F
Hydrophobic
Polar
Positive
Negative

The proposed mechanisms of Lactoferricin are based primarily on in vitro and animal studies. Human mechanistic data is lacking.

How It Works (Simplified)

Lactoferricin acts as a natural antimicrobial by disrupting microbial membranes through several key mechanisms:

Electrostatic Attraction

Cationic peptide (+8 charge) binds to negatively charged bacterial membranes via electrostatic attraction, initiating the killing process.

Membrane Disruption

Amphipathic structure allows insertion into lipid bilayers, forming pores that cause membrane permeabilization and cell content leakage.

Selective Toxicity

Human cells have neutral, cholesterol-rich membranes that resist attack, while bacterial and cancer cells have vulnerable anionic surfaces.

Apoptosis Induction

In cancer cells, triggers mitochondrial apoptosis pathway via ROS generation and caspase activation, independent of membrane lysis.

Key Research: Bellamy W et al. (1993) demonstrated rapid binding to bacterial surfaces with over 10 million molecules per cell, disrupting membrane permeability. PMID:8300449

Important Limitations

  • Almost all research is preclinical (in vitro and animal studies)
  • No human clinical trials have evaluated therapeutic efficacy
  • Stability and delivery challenges limit in vivo applications
  • Optimal formulation for systemic use remains unknown
  • Pharmacokinetics in humans not characterized
i. Membrane Disruption Pathway · Antimicrobial
LfcinB (+8 charge)Electrostatic binding to anionic membraneMembrane insertionPore formation / Carpet modelMembrane permeabilizationCell death
ii. Apoptosis Pathway · Anticancer
LfcinBPhosphatidylserine targetingROS generationCaspase-2 activationMitochondrial depolarizationCaspase-9/3Apoptosis
Mechanism Electrostatic binding to anionic bacterial membranes followed by membrane permeabilization
Supported 8 direct studies
Benefit shown to kill bacteria through membrane disruption
Evidence Level
Low
3 Animal
12 In Vitro
Mechanism Selective targeting of cancer cell membranes with exposed phosphatidylserine
Emerging 5 direct studies
Benefit may induce apoptosis in cancer cells
Evidence Level
Very Low
2 Animal
6 In Vitro
Mechanism Modulation of innate immune cell activation including macrophages and NK cells
Emerging 4 direct studies
Benefit suggested to enhance innate immune responses
Evidence Level
Very Low
3 Animal
4 In Vitro
Mechanism Direct interaction with fungal cell membranes causing cell death
Supported 4 direct studies
Benefit shown to exhibit antifungal activity
Evidence Level
Very Low
2 Animal
5 In Vitro
Mechanism Confidence
Established
Supported
Emerging
Evidence Level
High
Moderate
Low
Very Low
Phase 01 1
Immediate

Based on in vitro observations: Rapid binding to microbial membranes occurs within minutes. Bellamy et al. demonstrated over 10 million molecules binding per bacterial cell. Membrane permeabilization follows quickly. No human pharmacokinetic data available.

PMID:8300449
Phase 02 2
Hours

In vitro studies show bacterial killing within 1-4 hours at effective concentrations. Membrane depolarization contributes to cell death. In vivo timeline in humans is completely unknown.

PMID:11248238
Phase 03 3
Days

Animal model studies showed survival benefits over several days of observation, including improved survival of endotoxemic mice treated with lactoferricin B-derived peptides. Antifungal effects in mouse models observed over the treatment period. Human therapeutic timelines not established.

PMID:28287172
Phase 04 4
Long-term

No long-term human studies exist. Stability, bioavailability, and sustained efficacy in humans are completely unknown. Research focus remains on developing stable formulations for potential therapeutic use.

Research-based observations

This timeline reflects observations from published clinical and preclinical studies. Individual responses may vary significantly. This is not a guarantee of effects or a dosing schedule. Consult qualified healthcare providers for personalized guidance.

Good Signs (6 indicators)
White to off-white lyophilized powder
Dissolves completely in appropriate buffer or water
Clear, colorless solution after reconstitution
Certificate of analysis (COA) showing >95% purity
HPLC and mass spectrometry verification available
Proper vacuum seal on vial before reconstitution
Warning Signs (5 indicators)
Slightly off-white powder (may still be acceptable)
Takes longer than expected to dissolve
Powder appears collapsed or clumped
COA from manufacturer only without third-party verification
Purity listed below 95% but above 90%
Bad Signs (6 indicators)
Yellow, brown, or otherwise discolored powder
Visible particles or cloudiness after reconstitution
Gel-like consistency or aggregation that won't dissolve
No COA provided or COA appears fraudulent
Strong unusual odor
Vial seal appears compromised or previously opened
Positive quality indicator
Requires evaluation
Potential quality issue

For Research Evaluation Only

These quality indicators are general guidelines based on typical peptide characteristics. Professional laboratory testing (HPLC, mass spectrometry) provides definitive quality verification. This checklist is for initial visual evaluation only.

Synergistic
Compatible
Caution
Avoid

LL-37

Synergistic
Synergistic

Both are cationic antimicrobial peptides with membrane-disrupting mechanisms. May have additive or synergistic antimicrobial effects through similar but complementary membrane targeting. No direct interaction studies available.

Non-overlapping mechanisms. Lactoferricin acts directly on microbial membranes while Thymosin Alpha-1 modulates adaptive immunity. Theoretical complementary benefits for immune support.

Different mechanisms of action. Lactoferricin focuses on antimicrobial activity while BPC-157 targets tissue repair. No known contraindications.

Non-overlapping mechanisms. GHK-Cu supports tissue remodeling via copper signaling while Lactoferricin provides antimicrobial activity. May complement each other in wound healing contexts.

Research Note: Interaction data is based on published literature, mechanistic understanding, and theoretical considerations. Most peptide combinations lack direct clinical study. This information is for educational purposes only and does not constitute medical advice. Always consult qualified healthcare providers.

This dossier synthesizes available evidence from peer-reviewed literature, regulatory documents, and clinical trial registries. Evidence strength ratings follow a modified GRADE approach.

For complete methodology details, see our Methodology page.

Important Disclaimer

This dossier is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider before making health decisions.

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