Abstract
When PCR was first introduced for routine use in diagnostic laboratories in the 1980s, the technology opened the door to a new and dynamic future for detection of disease agents. However, the implementation of PCR technology in animal health laboratories far outpaced the development of documented guidelines and standards for use. In 2011, an effort was initiated within the American Association of Veterinary Laboratory Diagnosticians (AAVLD) membership to share PCR-based testing experiences more formally, as well as to document relevant laboratory science for the benefit of all animal health laboratories. The AAVLD “Laboratory Technology Committee” was formed during the annual 2011 AAVLD/USAHA meeting to provide a platform for laboratorians to exchange and discuss new testing technologies, including but not limited to molecular-based tests. The committee members devised a plan to combine the plethora of PCR-based testing experiences and best practices into general guidance documents to assist laboratories in establishing and performing PCR within their own unique laboratory settings. The committee formulated an overall goal of helping to provide consistent, high-quality molecular-based testing for the veterinary diagnostic laboratory community.
This issue of the Journal of Veterinary Diagnostic Investigation, the Focus issue on PCR best practices, includes a series of 6 papers that represent the cumulative work of the committee over the ensuing years, as collated by a core group of primary authors. Over the years, members rotated off the committee, refocused their areas of interest, or retired from diagnostic work, while new diagnosticians with new experiences joined the ongoing effort. It is important for all of those individuals to know that the core authors of these focus issue papers have made a concerted effort to include all contributors to the relevant manuscripts as coauthors. To anyone who has been inadvertently missed, our sincere apologies and genuine thanks for your efforts. The core authors would especially like to express gratitude to contributors who laid the foundation for this special issue: Steve Bolin, Mankey Bounpheng, Amy Glaser, Susan Hinkley, Roger Maes, Donna Mulrooney, Jan Pedersen, and Suelee Robbe-Austerman.
Among the topics specifically addressed in the focus issue papers are: a comparison of different international validation guidelines, with suggested practices for assay development and validation for real-time PCR assays 5 ; performance of pre-analytical, analytical, and post-analytical steps to ensure reliable real-time PCR assays 4 ; the different types of internal assay controls that would ideally be included in PCR-based testing to detect and manage the inhibitory substances commonly associated with different specimen matrices 6 ; guidance for sample preparation, submission to sequencing applications, and quality assessment of data obtained when using Sanger-based genetic sequencing in the context of diagnostic laboratory use 1 ; a methodologic review of test validation studies for infectious diseases in wild mammals with a focus on study design, statistical analysis, and reporting of results 2 ; and the report of a new open-source real-time PCR assay for Mycoplasma cynos using principles and guidance as outlined in the associated papers from the Laboratory Technology Committee. 3 The complete protocol of the M. cynos tuf assay is provided to facilitate assay harmonization. 3
An ancillary benefit to publishing these best practices and guidelines is that authors interested in submitting to JVDI will have another option to follow when planning validation studies and preparing a manuscript. These guidelines provide more specific guidance for validation of PCR assays for use in veterinary laboratories and have been added to the JVDI Instructions to Authors (https://journals.sagepub.com/author-instructions/VDI).
The authors, and the membership of the Laboratory Technology Committee of the AAVLD, sincerely hope that the information provided by their multi-year, special effort will prove useful to the animal health laboratory community.