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Updated: Nov 1, 2025
Microfluidic Production of Lysolipid-Containing Temperature-Sensitive Liposomes
Published on: March 3, 2020
Sustained Release of a Streptococcus pneumoniae Endolysin from Liposomes for Potential Otitis Media Treatment
Maria Daniela Silva1,2, Juan L Paris2, Francisco Miguel Gama1
1CEB-Centre of Biological Engineering, University of Minho, 4710-057 Braga, Portugal.
Abstract:
Local delivery of antimicrobials for otitis media treatment would maximize therapeutic efficacy while minimizing side effects. However, drug transport across the tympanic membrane in the absence of a delivery system is challenging. In this study, the MSlys endolysin was encapsulated in deformable liposomes for a targeted treatment of S. pneumoniae, one of the most important causative agents of otitis media. MSlys was successfully encapsulated in liposomes composed of l-alpha-lecithin and sodium cholate (5:1) or l-alpha-lecithin and PEG2000 PE (10:1), with encapsulation efficiencies of about 35%. The PEGylated and sodium cholate liposomes showed, respectively, mean hydrodynamic diameters of 85 and 115 nm and polydispersity indices of 0.32 and 0.42, both being stable after storage at 4 °C for at least one year. Both liposomal formulations showed a sustained release of MSlys over 7 days. Cytotoxicity studies against fibroblast and keratinocyte cell lines revealed the biocompatible nature of both MSlys and MSlys-loaded liposomes. Additionally, the encapsulated MSlys showed prompt antipneumococcal activity against planktonic and biofilm S. pneumoniae, thus holding great potential for transtympanic treatment against S. pneumoniae otitis media.
Insights
MSlys endolysin encapsulated in liposomes offers targeted otitis media treatment. This approach enhances antimicrobial delivery across the tympanic membrane, showing potential for treating Streptococcus pneumoniae infections.
Area of Science:
- Biotechnology
- Drug Delivery Systems
- Microbiology
Background:
- Otitis media treatment requires effective antimicrobial delivery to the middle ear.
- Drug transport across the tympanic membrane is a significant challenge.
- Streptococcus pneumoniae is a primary causative agent of otitis media.
Purpose of the Study:
- To develop liposomal formulations for local delivery of MSlys endolysin.
- To evaluate the efficacy of MSlys-loaded liposomes against S. pneumoniae.
- To assess the potential for transtympanic treatment of otitis media.
Main Methods:
- MSlys endolysin was encapsulated in deformable liposomes using l-alpha-lecithin with sodium cholate or PEG2000 PE.
- Liposome characteristics (size, polydispersity, stability) were analyzed.
- Antimicrobial activity against planktonic and biofilm S. pneumoniae was tested.
- Cytotoxicity of MSlys and liposomes was evaluated on fibroblast and keratinocyte cell lines.
Main Results:
- Successful encapsulation of MSlys in liposomes with ~35% efficiency.
- Liposomes exhibited mean hydrodynamic diameters of 85-115 nm and remained stable for over a year.
- Sustained release of MSlys from liposomes over 7 days was observed.
- MSlys-loaded liposomes demonstrated biocompatibility and potent activity against S. pneumoniae.
Conclusions:
- Deformable liposomes are effective carriers for MSlys endolysin.
- Liposomal MSlys shows sustained release and potent antimicrobial activity.
- This formulation holds promise for transtympanic otitis media treatment.
