BioProject

To determine the transcriptional response to Salmonella enterica serovar Enteritidis (SE) infection, a newly developed chicken 44K Agilent array was used to analyze total RNA of heterophils from SE-resistant (line A) and SE–susceptible chickens (line B), treated with in vitro infection of SE (I) or non SE medium (N) for 1 hr. A dual-color balanced design was used to provide a direct comparison between SE-infected and non-infected groups (AI/AN, BI/BN) and between line A and line B (AN/BN, AI/BI). Data retrieved from 426 immunologically important genes were used for functional analysis. The results indicated that: In the comparisons of SE infection with non-infection, 39 genes were found differentially expressed (P < 0.05 with at least 2-fold) after Salmonella infection, while 21 genes were found differentially expressed between different lineages. Numerous of members in Toll-like receptor (TLR) signaling pathway were identified which include receptors: MD-2, TLR-4, -5, -15; adaptors: TLR adaptor molecule1 (TICAM1/TRIF), MAP kinase kinase 3 (MKK3) and NFkB-1, as well as cytokines, chemokines and costimulatory molecule: interleukin (IL)-1β, IL-6, IL-8, IL-12, chemokine (C-X-C motif) ligand 1, chemokine (C-C motif) ligand 4, CCL 5, and CD80. Most of immune genes were up-regulated after SE infection, and the magnitude of up-regulation was higher in line A than line B in general. The results suggested that a similar TLR regulatory network exists in both lines with strong response in resistant line. This finding has laid the foundation for further study of molecular and cellular modulation of SE infection in chickens. Keywords: disease state analysis Overall design: A dual color, balanced design was carried on for all of heterophils samples from sixteen chickens. Each sample type (AI, AN, BI and BN) includes four biological replication for labeling. A Dye swap was used in each pair of comparisons including AI/AN, BI/BN, and AI/BI, and AN/BN. Background subtracted signal intensity were collected from 16 arrays and normalized for data analysis.