Related Experiment Video
Updated: Oct 2, 2026
An In Vitro Organ Culture Model of the Murine Intervertebral Disc
Published on: April 11, 2017
A new in-vitro model to investigate antibiotic penetration of the intervertebral disc
R de W Thomas1, J J Batten, S Want
1Department of Orthopaedics, Royal Postgraduate Medical School, Hammersmith Hospital, London, UK.
Abstract:
We have studied the ability of a range of antibiotics to penetrate intervertebral disc tissue in vitro, using a mouse disc model. Equilibrium concentrations of antibiotics incorporated into the entire disc were determined by bioassay using a microbial growth-inhibition method. Uptake was significantly higher with positively-charged aminoglycosides compared with negatively-charged penicillins and cephalosporins. Uncharged ciprofloxacin showed an intermediate degree of uptake. Our results support the hypothesis that electrostatic interaction between charged antibiotics and negatively-charged glycosaminoglycans in the disc is an important factor in antibiotic penetration, and may explain their differential uptake.
Insights
Antibiotic penetration into intervertebral discs varies by charge. Positively charged antibiotics show higher uptake, suggesting electrostatic interactions with disc tissue influence drug delivery for better treatment outcomes.
Area of Science:
- Pharmacology
- Biomedical Engineering
- Tissue Engineering
Background:
- Intervertebral disc infections are challenging to treat due to poor antibiotic penetration.
- Understanding factors influencing antibiotic uptake in disc tissue is crucial for effective antimicrobial strategies.
Purpose of the Study:
- To investigate the in vitro penetration of various antibiotics into mouse intervertebral disc tissue.
- To determine the relationship between antibiotic charge and its concentration within the disc.
Main Methods:
- Utilized a mouse disc model for in vitro antibiotic penetration studies.
- Quantified antibiotic concentrations using a microbial growth-inhibition bioassay.
- Compared uptake of positively charged, negatively charged, and uncharged antibiotics.
Main Results:
- Significantly higher equilibrium concentrations of aminoglycosides (positively charged) were observed compared to penicillins and cephalosporins (negatively charged).
- Uncharged ciprofloxacin exhibited intermediate uptake levels.
- Differential antibiotic uptake correlated with their electrostatic properties.
Conclusions:
- Electrostatic interactions between charged antibiotics and negatively charged glycosaminoglycans in the disc play a significant role in antibiotic penetration.
- This interaction helps explain the observed variations in antibiotic uptake within the intervertebral disc tissue.
- Findings support targeted antibiotic selection based on charge for improved disc infection treatment.
