Project description:To identify markers associated with inherent cellular sex-identity, we analysed macrophages from newly-hatched chicks. We found that male and female macrophages respond differently to stimulation by bacterial lipopolysaccharide and that female macrophages constitutively express higher levels of interferon target genes than male macrophages.
Project description:The first period post-hatch with all its stimuli could potentially be stressful for the chicks, and by that affect the welfare of the chicken as they mature. By measuring changes in the transcriptome, along with behavioural phenotypes and hormonal levels, the aim is to investigate short and long term effects on the chicken. One batch of chicken were hatched in a production environment, and underwent the same treatment all newly hatched production animals do (sorting, sexing and transportation). Eggs of the same age were simultaneously incubated and hatched in a control environment in a lab. From the end of day one after hatch, both groups were reared under the same conditions in the lab.
Project description:To identify markers associated with inherent cellular sex-identity, we analysed macrophages from newly-hatched chicks. We found that male and female macrophages respond differently to stimulation by bacterial lipopolysaccharide and that female macrophages constitutively express higher levels of interferon target genes than male macrophages. Macrophages were collected from leg-bones of chickens between 1 and 3 days after hatch. Three pools of macrophage cells were made for male and female cultures. Cells were cultured in either standard medium or in medium containing lipopolysaccharide (LPS) to activate the macrophages. Macrophages were harvested and RNA collected for microarray analysis.
Project description:Newly-hatched domestic chick serves as an important model for studies of neural and behavioral plasticity, particularly with respect to learning and memory such as filial imprinting. Imprinting is assumed to be a unique case of recognition learning with some characteristic features, such as sensitive period and irreversibility. However, the molecules involved in the memory process are yet to be fully identified. To address this issue, we attempted to identify the genes differentially expressed at an earlier phase of filial imprinting than described in our previous report (Brain Res. Bull.76, 275-281 (2008)). One-day-old chicks were trained for imprinting for 1 h and whole brains were collected and used for cDNA microarray analysis and quantitative RT-PCR. We identified 18 genes upregulated accompanying filial imprinting. These results suggested that the increase of these 18 genes associated with filial imprinting might play an important role in the acquisition of memory in the filial imprinting. Total RNA was extracted from whole brains of trained chicks (n=16) and control dark-reared chicks (n=16). Using these total RNAs, we performed RT-PCR to distinguish male chicks from females. Then total RNAs were separated and mixed in four groups (1, male trained (n=8); 2, female trained (n=8); 3, male dark-reared (n=8); and 4, female dark-reared chicks (n=8)), and we performed cDNA microarray expression analysis to identify the upregulated genes following imprinting (1 versus 3 and 2 versus 4).
Project description:Epigenetic regulation of gene expression plays a pivotal role in the orchestration of immune responses and may determine the vigor, quality, or longevity of such responses. Chemical allergens can be divided into two categories: skin sensitizing chemicals associated with allergic contact dermatitis, and chemicals that cause sensitization of the respiratory tract and occupational asthma. In mice these are characterized by different T helper (Th) cell responses. To explore the regulation and maintenance of these divergent responses, mice were exposed to 2,4-dinitrochlorobenzene (DNCB; a contact allergen) or trimellitic anhydride (TMA; a respiratory allergen). DNA from draining lymph nodes was processed for methylated DNA immunoprecipitation (MeDIP) followed by hybridization to a whole-genome DNA promoter array. 6319 differently methylated regions (DMR) were identified following DNCB treatment, while 2178 DMRs were measured following TMA treatment, with approximately half of the TMA DMR common to DNCB. When limited to promoter region-associated DMR, 637 genes were uniquely associated with DNCB induced DMR but only 164 genes were unique to TMA DMR. Promoter-associated DMR unique to either DNCB or TMA were generally hypomethylated whereas DMR common to both allergens tended to be hypermethylated. Pathway analyses highlighted a number of immune related pathways, including chemokine and cytokine signalling. These data demonstrate that chemical allergen exposure results in characteristic patterns of DNA methylation indicative of epigenetic regulation of the allergic response. Comparison of methylation profiles from allergens 2,4-dinitrochlorobenzene (DNCB; a contact allergen) and trimellitic anhydride (TMA; a respiratory allergen) or vehicle acetone:olive oil (AOO).
Project description:Methylene diphenyl diisocyanate is a chemical known to cause asthma. The present study uses mice to investigate exposure-induced changes in lung gene expression and effects of a chloride channel inhibitor We used microarrays to detail global whole lung gene expression following respiratory tract exposure to methylene diphenyl diisocyanate (MDI) vs. control exposure in mice immune-sensitized to MDI by prior skin exposure. In some studies mice were given a chloride channel inhibitor (crofelemer) via the respiratory tract before MDI.
Project description:Bovine respiratory epithelial cells have different susceptibility to bovine
respiratory syncytial virus infection. The cells derived from the lower
respiratory tract were significantly more susceptible to the virus than those
derived from the upper respiratory tract. Pre-infection with virus of lower
respiratory tract with increased adherence of P. multocida; this was not the
case for upper tract. However, the molecular mechanisms of enhanced
bacterial adherence are not completely understood. To investigate whether
virus infection regulates the cellular adherence receptor on bovine trachea-,
bronchus- and lung-epithelial cells, we performed proteomic analyses.