Project description:Mycoplasma species are highly contagious pathogens, and Mycoplasma infectious disease are a serious issue for the dairy industry. The bovine peripheral blood mononuclear cells play an important role for mycoplasma mastitis, however, the effects of M. bovis for immune response of peripheral blood mononuclear cells have not been fully clarified.We examined the transcription profiling of bovine peripheral blood mononuclear cells in intramammary infusion of M. bovis at day 7.
Project description:Escherichia coli and Staphylococcus aureus are two common pathogenic microorganisms that cause mastitis in dairy cows. They can cause clinical mastitis and subclinical mastitis. In recent studies, lncRNAs have been found to play an important role in the immune responses triggered by microbial inducers. However, the actions of lncRNAs in bovine mastitis remain unclear. The purpose of this study was to explore the lncRNA profile on mastitis.
Project description:Bovine mastitis causes changes in the serum exosomal miRNAs expression. Serum samples from healthy dairy cows (n = 7) were compared to those of cows with subclinical (n = 7 ) using small RAN sequencing. Three hundred fifty-five miRNAs (341 known and 14 novel ones) were identified. There were 42 miRNAs up-regulated in serum-derived EVs from cows with subclinical mastitis, including bta-miR-1246, bta-miR-2431-3p, bta-miR-126-3p, bta-miR-29a, etc. The MAPK signaling pathway was the most affected pathway by clinical mastitis. Thus, miRNA alterations in mastitis serum-derived EVs support the potential regulator role of specific miRNAs as exosomal cargo in clinical mastitis physiology.
Project description:Establishment of an in vitro system to explore molecular mechanisms of mastitis susceptibility in cattle by comparative expression profiling of Escherichia coli and Staphylococcus aureus inoculated primary cells sampled from cows with different genetic predisposition for somatic cell score Primary bovine mammary gland epithelial cells (pbMEC) were sampled from the udder parenchyma of cows that were selected for high and low mastitis susceptibility by applying a marker assisted selection strategy considering QTL and molecular marker information of a repetitively confirmed QTL for SCS in the telomeric region on BTA18 The cells were cultivated and subsequently inoculated with heat inactivated mastitis pathogens Escherichia coli and Staphylococcus aureus, respectively. After 1, 6 and 24 hours the cells were harvested and comparatively analyzed using microarray expression chip technology to identify differences in mRNA expression profiles attributed to cultivation, inoculation or to genetic predisposition.
Project description:We performed a genome-wide transcriptional analysis in the mammary gland in a mouse model of E. coli mastitis using high-density mouse oligonucleotide microarrays. This global transcription analysis revealed that about 7% of tested genes are mobilized in the mouse mammary gland to E. coli endotoxin. We identified 1402 differentially expressed genes that were associated with physiological system development/function and molecular/cellular functions and metabolic/signalling pathways that are highly relevant to host immune-inflammatory defense response against E. coli infection. The mouse differentially expressed genes through the use of comparative mapping/genomics and positional information on reported QTL for bovine mastitis allowed identifying 293 potential candidate genes for bovine mastitis. This study will enable other researchers to combine our mRNA expression data with genetic association studies to discover genomic variation underlying variation of susceptibility to mastitis in dairy cows. Keywords: time course, disease state analysis
Project description:Establishment of an in vitro system to explore molecular mechanisms of mastitis susceptibility in cattle by comparative expression profiling of Escherichia coli and Staphylococcus aureus inoculated primary cells sampled from cows with different genetic predisposition for somatic cell score Primary bovine mammary gland epithelial cells (pbMEC) were sampled from the udder parenchyma of cows that were selected for high and low mastitis susceptibility by applying a marker assisted selection strategy considering QTL and molecular marker information of a repetitively confirmed QTL for SCS in the telomeric region on BTA18 The cells were cultivated and subsequently inoculated with heat inactivated mastitis pathogens Escherichia coli and Staphylococcus aureus, respectively. After 1, 6 and 24 hours the cells were harvested and comparatively analyzed using microarray expression chip technology to identify differences in mRNA expression profiles attributed to cultivation, inoculation or to genetic predisposition. Six heifers inheriting the favorable paternal QTL allele and five heifers inheriting the unfavorable QTL allele were selected by applying a marker assisted selection strategy. All heifers were kept under the same environmental conditions, had no clinical mastitis and did not show any indication of bacterial infection at slaughter. Primary bovine mammary gland epithelial cell cultures were established from cells sampled from the udder parenchyma of each cow. The cells were challenged with heat inactivated Escherichia coli and Staphylococcus aureus or with PBS for control. After 1, 6 and 24 hours the cells were harvested and mRNA expression was comparatively analyzed between time points for each treatment and each paternally inherited SCS-BTA18-QTL allele, respectively. In addition, the differences in gene expression at time points 1, 6 and 24h between inoculated and respective uninoculated control cells were investigated using the short time series expression miner STEM for co-expression profiling and GO cattegory enrichment analyses.
Project description:Early detection of bovine subclinical mastitis may improve treatment strategies and reduce the use of antibiotics. Herein, individual milk samples from Holstein cows affected by subclinical mastitis induced by S. agalactiae and Prototheca spp. were analyzed by untargeted and targeted mass spectrometry approaches to assess changes in their peptidome profiles and identify new potential biomarkers of the pathological condition. Results showed a higher amount of peptides in milk positive at the bacteriological examination when compared with the negative control. However, the different pathogens seemed not to trigger specific effects on milk peptidome. The peptides that best distinguish positive from negative samples are mainly derived from the most abundant milk proteins, especially from β- and αs1-casein, but also include the antimicrobial peptide casecidin 17. These results provide new insights into the physiopathology of mastitis. Upon further validation, the panel of potential discriminant peptides could help to the development of new diagnostic and therapeutic tools.
Project description:Mastitis is a common disease that hinders the development of dairy industry and animal husbandry. It leads to the abuse of antibiotics, the emergence of super drug-resistant bacteria, and poses a great threat to human food health and safety. Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) are the most common pathogens of mastitis in dairy cows and usually cause subclinical or clinical mastitis. CircRNAs and N6-methyladenosine (m6A) play important roles in immunological diseases. However, the mechanisms by which m6A modifies circRNA in bovine mammary epithelial cells remain poorly understood. The aim of our study was to investigate m6A-modified circRNAs in bovine mammary epithelial cells (MAC-T cells) injured by S. aureus and E. coli. The profile of m6A-modified circRNA showed a total of 1599 m6A peaks within 1035 circRNAs in the control group, 35 peaks within 32 circRNAs in the S. aureus group, and 1016 peaks within 728 circRNAs in the E. coli group. Compared with the control group, 67 peaks within 63 circRNAs were significantly different in the S. aureus group, and 192 peaks within 137 circRNAs were significantly different in the E. coli group. Furthermore, we found the source genes of these differentially m6A-modified circRNAs in the S. aureus and E. coli groups with similar functions according to GO and KEGG analyses, which were mainly associated with cells injury, such as inflammation, apoptosis, and autophagy. CircRNA-miRNA-mRNA interaction networks predicted the potential circRNA regulation mechanism in S. aureus- and E. coli-induced cell injury. We found that the mRNAs in the networks, such as BCL2, MIF and TNFAIP8L2, greatly participated in the MAPK, WNT, and inflammation pathways. This is the first report on m6A-modified circRNA regulation of cells under S. aureus and E. coli treatment, and sheds new light on potential mechanisms and targets from the perspective of epigenetic modification in mastitis and other inflammatory diseases.