Submitted to: Veterinary Parasitology
Publication Type: Review Article
Publication Acceptance Date: 6/15/2012
Publication Date: 6/23/2012
Citation: Li, R.W., Choudhary, R.K., Capuco, A.V., Urban, Jr., J.F. 2012. Exploring the host transcriptome for mechanisms underlying protective immunity and resistance to helminth infection in ruminants. Veterinary Parasitology. 190(1-2):1-11. Interpretive Summary: Parasitic nematodes have important economic consequences and result in a significant loss to the American cattle industry. Limited knowledge on molecular mechanisms underlying host resistance in cattle has hindered the development of vaccines as well as parasite resistant animals. We here reported an in-depth review on knowledge recently obtained on parasite resistance using transcriptome analysis. We discussed genes and multiple signaling pathways that affect parasite resistance. Farmers could potentially benefit from our research by having parasite resistant animals and therefore increased profitability. Consumers will ultimately benefit from our research by having affordable meat and milk products with less drug residues.
Technical Abstract: Helminth infections in ruminants are a major impediment to the profitable production of meat and dairy products, especially for small farmers. Gastrointestinal parasitism is not just a disease that negatively impacts productivity, including reduced weight gain and milk yield, but is also a leading cause of mortality in small ruminants. The current parasite control strategy involves heavy uses of anthelmintics, which has resulted in the emergence of drug-resistant strains. This, in addition to increasing demand for animal products that are free of drug residues (or consumer perception of residues), has called for urgent development of alternative strategies for parasite control, including selective breeding of parasite resistant ruminants. The development of protective immunity and manifestations of resistance to helminth infections relies upon the precise control of expression of the host genome. Understanding molecular mechanisms underlying these processes represents a key step towards the development of effective alternative parasite control strategies. Recent progress in characterizing the transcriptome of both host and parasites utilizing high-throughput microarrays and RNA-seq technology, has led to the identification of unique features of host-parasite interactions and the genes and biological pathways involved. Knowledge obtained regarding the different mechanisms of host immune responses to critical changes in the developmental stages, physiology, and virulence of a parasite has the potential to identify optimal windows for immunological intervention. Comparative transcriptome analysis, in concert with genome-wide association (GWS) studies to identify quantitative trait loci (QTLs) affecting host resistance, has emerged as a promising means to unravel the molecular basis and global regulatory networks that underlie complex traits such as parasite resistance.