Submitted to: BioMed Central (BMC) Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/25/2013
Publication Date: 11/25/2013
Citation: Kim, D., Lillehoj, H.S., Lee, K., Neumann, A., Siragusa, G., Lillehoj, E. 2013. Genome-Wide differential gene expression profiles in broiler chickens with gangrenous dermatitis. BioMed Central (BMC) Genetics. 56:670-679. Interpretive Summary: There are increasing concerns on gangrenous dermatitis (GD) which is caused by anaerobic clostridial bacteria, especially Clostridium septicum (CS) and C. perfringens (CP) type A. There is currently no vaccines against GD. In this paper, ARS scientists collaborated with scientists from universities and private industry and investigated host immune response to GD in field outbreak cases using functional genomics technology. In chickens which are afflicted with GD, there was increased gene expression associated with high inflammatory response, and immunohistological examination of infected skin confirmed the presence of activ ated lymphocytes. These new information will enhance our insights on host-pathogen interaction in GD and will be used by scientists in academia and industry to develop novel control strategies against GD.
Technical Abstract: Gangrenous dermatitis (GD) is a disease of poultry associated with the infection of Clostridium septicum (CS) and/or C. perfringens (CP) type A. While GD causes significant morbidity, mortality, and economic loss to the poultry industry, the fundamental mechanisms underlying this host-pathogen interaction are relatively unknown. This study utilized comparative global gene expression microarray analysis of GD-affected and clinically healthy chickens from a recent GD outbreak to glean insights into the molecular and cellular changes associated with this disease process. The levels of mRNAs extracted from skin and underlying muscle corresponding to 952 microarray elements were altered between GD-afflicted birds and healthy controls, with 468 being increased and 484 decreased. From these, 386 chicken genes were identified and used for biological function and pathway analyses. The biological functions that were most significantly associated with the differentially expressed genes were classified under the ‘Disease and Disorders’ and ‘Molecular and Cellular Functions’ categories. The most significant functions of each category were ‘Inflammatory Response’ and ‘Cellular Growth and Proliferation’, respectively. The biological pathway that was most significantly associated with the differentially expressed genes was the nuclear factor-erythroid 2-related factor 2 (NRF2)-mediated oxidative stress pathway. Histopathological and immunohistochemical analyses confirmed extensive skin and muscle damage with concurrent infiltration of K1+, K55+, and CD8+ lymphocytes in the GD-afflicted birds, but not the health controls. These results provide new information concerning host gene expression patterns during GD.