How to Reduce Animal Experimentation in Medicine?
The number of animals used for experimentation especially for development of new drugs has shown a dramatic rise with increase in morbidities in people. Yes, the scientific world is sensitised about it and working on the 3R principle- 'reduce', 'refine' 'replace' .
The scientists at University of Geneva (UNIGE) have developed an ex vivo model of human lung epithelial cell cultures, whose function is to form a protective barrier and ensure the hydration of mucus. Pseudomonas aeruginosa is a known bacterium causing lung infection in people with weakened immune system or cystic fibrosis. Most of the bacteria are becoming immune to antibiotics, according to Thilo Kohler, a researcher in the Department of Microbiology and Molecular Medicine at UNIGE.
Using the ex vivo model (made from organ samples extracted from living body) of lung epithelial cells, the team tested a combination of antibiotics with bacteriophages (viruses that attack on bacteria and kill them) to find out the effectiveness.
Two types of cells were used: healthy cells and cells with mutation in the cftr gene, which causes cystic fibrosis. Building on an existing technology, we created a new model adapted to a pulmonary setting in the context of a Pseudomonas infection”, explains Thilo Köhler. “In addition, we used cells that reproduce cystic fibrosis in order to establish whether the treatment we propose could also effectively treat lung infections affecting these patients.” Moreover, the evaluation of the efficacy of a phage/antibiotic combination in an animal model carried out by another team validates the ex vivo model using human cells: it is just as effective, while coming as close as possible to the clinical reality. It could therefore be adapted to other types of lung infection to study the effectiveness of new treatments without having to use animals.
Thilo Kohler is of the view that bacteria P.aeruginosa bacteria develop resistance to treatment if antibiotic (ciprofloxacin) is administered while in combination with bacteriophages the epithelial cells are better protectors. Most of the bacteria disappear and the few survivors have lost their dangerousness.
Our results are positive in the healthy cell model as well as in the model using cells with a cftr gene mutation, which is very good news!” Thilo Köhler is pleased to say. Moreover, this type of treatment does not induce an inflammatory reaction, showing that it is highly acceptable to the organism, which does not seek to defend itself against the drug. The model won the UNIGE 3R prize.