Transcriptional Analysis of Host-Pathogen Interaction in Genetically Disparate Chicken Lines Showing Different Levels of Disease Susceptibility to Necrotic Enteritis

Authors: Kim, Duk Kyung; Lillehoj, Hyun; Jang, Seung; Lee, Sung; Hong, Yeong; Cheng, Hans

Submitted to: PLOS ONE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/15/2014
Publication Date: 12/11/2014
Publication URL: http://handle.nal.usda.gov/10113/61086
Citation: Kim, D., Lillehoj, H.S., Jang, S.I., Lee, S.H., Hong, Y.H., Cheng, H.H. 2014. Transcriptional analysis of host-pathogen interaction in genetically disparate chicken lines showing different levels of disease susceptibility to necrotic enteritis. PLoS One. 9(12):e114960.

Interpretive Summary: Necrotic enteritis (NE) is an emerging disease in the poultry industry with an estimated economic loss of $2 billion per year. There is a need to develop an effective disease prevention and control strategy against NE with the increasing regulation of antibiotics in animal agricultural production. In this study, ARS scientists collaborated with scientists at other institutions to investigate the underlying mechanisms of host-bacterial interaction to gain better understanding of the disease process in NE. Using a new technology that measures the abundance of gene products, the authors showed novel information concerning the nature of the host immune response altered by bacterial infection in certain lines of birds. The results will help scientists to understand the type of immune response associated with necrotic enteritis infection.

Technical Abstract: Necrotic enteritis (NE) has reemerged as a significant problem as a result of the growing concern over antibiotic resistance in human pathogens and restrictions on the use of antibiotics. It is difficult to reproduce NE by C. perfringens alone, therefore, a well established co-infection model using Eimeria maxima and C. perfringens was used in this study. Transcriptiome profiling and functional genomic approaches were applied to elucidate molecular mechanisms underlying the pathogenesis of NE and to gain better insights on the role of the host's immune response against NE infection in broiler chickens. In addition, we compared transcriptome differences between two inbred chicken lines, 6 and 7, which are well known to be resistant and susceptible to Marek’s disease, respectively. Functional analysis on the altered gene expression revealed that biological functions and networks related to “inflammatory response” were changed by NE infection, and functions and a pathway associated with leukocyte activity were also significantly affected. In the comparison of the disease phenotype between two inbred lines, line 6 was more susceptible to NE than line 7. Although both chicken lines have the identical major histocompatibility complex (MHC) genotype, the expression level of immune-related genes showed distinct expression profiles between NE-infected and uninfected chickens when compared across lines. Our results increase the understanding of the mechanisms for NE infection and host-pathogen immune responses, and consequently, will facilitate the development of more effective control strategies against these enteric pathogens.