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Efficacy and toxicity of the antimicrobial peptide M33 produced with different counter-ions

Alessandro Pini1, Luisa Lozzi, Andrea Bernini

  • 1Dipartimento di Biotecnologie, Università degli Studi di Siena, and Azienda Ospedaliera Universitaria Senese, Policlinico Le Scotte, Via Fiorentina 1, Siena, Italy. pinia@unisi.it

Amino Acids
|October 11, 2011
PubMed

Insights

The antimicrobial peptide M33 was tested in two salt forms for preclinical drug development. M33-acetate demonstrated lower toxicity and is more suitable for further development than M33-trifluoroacetate.

Area of Science:

  • Pharmacology
  • Drug Development
  • Biochemistry

Background:

  • The tetra-branched peptide M33 shows potential as an antimicrobial agent for lung infections and sepsis.
  • Preclinical drug development necessitates medium-scale peptide manufacturing for comprehensive testing.

Purpose of the Study:

  • To evaluate the behavior of peptide M33 with different counter-ions for optimal drug development.
  • To compare the activity and toxicity of M33 trifluoroacetate (TFacetate) and M33 acetate salts.

Main Methods:

  • Comparative in vitro and in vivo analysis of M33-TFacetate and M33-acetate.
  • Assessment of cytotoxicity in normal human bronchial cells and cystic fibrosis (CFTR-ΔF508) cells.
  • Evaluation of in vivo toxicity signs and duration post-administration in animal models.

Main Results:

  • Both M33-TFacetate and M33-acetate exhibited comparable efficacy in vitro and in vivo.
  • M33-TFacetate displayed significantly higher toxicity (5-30%) towards human bronchial and CFTR-ΔF508 cells compared to M33-acetate.
  • M33-TFacetate induced immediate and pronounced in vivo toxicity, while M33-acetate caused only transient, mild signs.

Conclusions:

  • M33-acetate is a more suitable salt form for the preclinical development of peptide M33 due to its improved safety profile.
  • The choice of counter-ion significantly impacts the toxicity of peptide M33 without affecting its antimicrobial efficacy.

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