Submitted to: Veterinary Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 21, 2001
Publication Date: November 1, 2001
Interpretive Summary: Differentiating parasites and diagnosing parasitic infections have long been performed using steadfast morphological and biological techniques. In recent years, molecular methods have substantially enhanced the sensitivity and specificity of the detection process, while reducing much of the subjectivity in interpreting morphological and biological data. Applications of PCR to answering questions associated with veterinary parasite research are still evolving, though the process appears to have taken its cues from technological advances driven by research on humans and on mouse models. Nonetheless, as state-of-the-art techniques such as the analysis of EST libraries, the generation of single nucleotide polymorphisms (SNP), laser capture microdissection, and the construction of PCR-based cDNA libraries from single cells, are combined with current advances in microarray and microchip technology for large scale gene analysis, scientists are able to ask highly targeted questions yet derive their answers from a more holistic assessment of the genetics of the parasite and/or the host. Heightened interest specifically in the area of PCR-derived methodologies has therefore prompted a review of its current and future applications to parasite diagnosis and differentiation, and on pathogen:host interfaces. The compilation and assessment of this research will assist in developing reproducible, inexpensive DNA-based diagnostic methods that will one day be performed on a routine basis, if not in the veterinarian's office, then clearly in a diagnostic laboratory.
Over the past 15 years, there has been a dramatic evolution in molecular approaches to studying parasites and parasitic diseases. Many of these advancements have been brought about through the development of new uses for the polymerase chain reaction (PCR). Enhancements in sensitivity that can be achieved using PCR now permit scientists to investigate anomalies at tthe level of a single cell, far below what is often times needed for parasite-derived applications. PCR has had a substantial impact on advances made in the areas of parasite systematics and epidemiology, immunology and host-parasite interactions, recombinant DNA vaccine development and most recently, the analysis of whole genomes either through directly sequencing the DNA, the analysis of expressed sequence tags (ESTs) or through the rapidly growing field of functional genomics. This article, however, will focus on the application of PCR methodology to parasite differentiation and dthe diagnosis of disease. Specific attention will be given to advances provided by multiplex PCR, fluorescence-based "real-time" PCR, and the utilization of PCR as a quantitative technique.