Validation of an alternative microbiological method for tissue products

Area of Science:

• Microbiology
• Pharmacology
• Biotechnology

Background:

• European Pharmacopoeia mandates 14-day sterility testing for products using thioglycollate and soya-bean casein media.
• Extended incubation periods pose challenges for routine tissue bank operations, impacting turnaround times for cornea and amnion grafts.

Purpose of the Study:

• To evaluate an alternative sterility testing method for tissue bank products.
• To reduce the incubation time while maintaining the detection limit, accuracy, and recovery rates of the reference method.

Main Methods:

• The study involved a two-step validation process comparing a reference method with an alternative sterility testing approach.
• Microorganisms (8 bacterial, 2 fungal strains) were tested using geometric dilutions in culture media.
• Fertility of culture media and parallel testing of products from two batches across three runs were conducted.

Main Results:

• No significant aberrations were found between the alternative and reference sterility testing methods.
• Microorganism recovery rates ranged from 83.33% to 100%.
• The alternative method demonstrated non-inferiority in accuracy compared to the reference method.

Conclusions:

• The alternative sterility testing method is a viable option for reducing incubation time.
• Sterility testing for cornea and amniotic grafts was successfully reduced to 9 days.