Rabbit Peritoneal Implant Model
- Duration - 7 days
- Lead time - 30 days
- Standard results - Microbiology, Histology
The rabbit peritoneal implant model is often used as the second screening tool (after the rat subcutaneous implant model) for companies developing hernia meshes. The coated mesh material is implanted into the peritoneal space of rabbits and challenged with bacteria (often E. coli, to mimic the most common contaminant in a hernia repair procedure). Variations of this model include the cecal sidewall adhesion model, also available from BRIDGE PTS.
- Create an incision into the peritoneal space.
- Suture the implant material (typically a hernia mesh) into the peritoneal wall.
- Contaminate the surface with bacteria.
- Close the incision and monitor for 7-14 days.
- Upon sacrifice, harvest mesh, surrounding tissue and peritoneal fluid, when present, for microbial counts.
How the Model Works:
In the Figure below we plot the course of exogenously applied E. coli to the peritoneal space after implantation of test or control hernia meshes. On post-implantation day 7, meshes were harvested along with surrounding tissues for bioburden assessments. In this study, both test materials were superior to both controls. Note that the bioburden in the tissues is consistently lower than the levels on the implant surfaces. However, when the bioburden of the implant is higher in one group than another, so too is the bioburden of the surrounding tissue. Surrounding tissue bioburden often reflects the infection state of the implant - - this is a "rule" that we find in 95%+ of all of our models.
advantages and disadvantages of this model:
This model is a great second step in the screening of antimicrobial actives and coatings for the treatment of infected hernia meshes (the first step being a pre-screening in our rat subcutaneous implant model). In the vast majority of cases, the findings in this model reflect what has been observed in our rat model. However, in relatively small (but critical!) number of cases, samples that perform well in the rats will fail in the rabbits. It is for this reason that we always recommend the model as a final follow-up test.
Another advantage to the model is that the FDA has accepted this data for submissions to achieve approval for human trials.
As with all of our infection studies, data turnaround is extremely rapid, with most customers having their top-line microbiology data within 48 hours of sample harvest.