Creation of an Antemortem Serological Diagnostic Test of <i>Parelaphostrongylus tenuis</i>

Parelaphostrongylus tenuis is a parasitic nematode common among deer, elk, moose, and horses. The parasites attack the central nervous system, laying their eggs in meningeal tissue resulting in high morbidity and mortality. Techniques currently available for the most accurate diagnosis include necropsy to detect adult worms in the brain and spinal cord. The goal of the present research was to develop a way to accurately diagnose P. tenuis infection antemortem. A gene encoding a P. tenuis protein was inserted into an expression plasmid and propagated in E. coli. The recombinant protein was affinity purified, separated on SDS-PAGE gels and transferred to nitrocellulose. Western blots were utilized to identify anti-P. tenuis antibody present in blood, serum and spinal fluid using sera from known positive and negative animals. Enzyme conjugated anti-cervid antibody produced in chickens was used to detect serologically positive elk, moose and deer. After western blots were confirmed to be effective diagnostics, enzyme-linked immunosorbent assays (ELISAs) were used to test overlapping 10-mer synthetic peptides for the development of a more cost effective, less labor-intensive test. However, due to inconsistent results and cross reactivity with other similar organisms, we have moved our attention to a full genomic analysis of P. tenuis to further distinguish a more definitive antigen. This effort is ongoing but is expected to identify epitopes that are unique to P. tenuis and serve as a useful diagnostic assay.