Identification of novel molecular markers of mastitis caused by Staphylococcus aureus using gene expression profiling in two consecutive generations of Chinese Holstein dairy cattle

Abstract

Background Mastitis in dairy cows caused by Staphylococcus aureus is a major problem hindering economic growth in dairy farms worldwide. It is difficult to prevent or eliminate due to its asymptomatic nature and long persistence of infection. Although transcriptomic responses of bovine mammary gland cells to pathogens that cause mastitis have been studied, the common responses of peripheral blood leukocytes to S. aureus infection across two consecutive generations of dairy cattle have not been investigated. Methods In the current study, RNA-Seq was used to profile the transcriptomes of peripheral blood leukocytes sampled from S. aureus-infected mothers and their S. aureus-infected daughters, and also healthy non-infected mothers and their healthy daughters. Differential gene expression was evaluated as follows: 1) S. aureus-infected cows versus healthy non-infected cows (S vs. H, which include all the mothers and daughters), 2) S. aureus-infected mothers versus healthy non-infected mothers (SM vs. HM), and 3) S. aureus-infected daughters versus healthy non-infected daughters (SMD vs. HMD). Results Analysis of all identified expressed genes in the four groups (SM, SMD, HM, and HMD) showed that EPOR, IL9, IFNL3, CCL26, IL26 were exclusively expressed in both the HM and HMD groups, and that they were significantly (P < 0.05) enriched for the cytokine-cytokine receptor interaction pathway. A total of 17, 13 and 10 differentially expressed genes (DEGs) (FDR Padj. < 0.1 and |FC| > 1.2) were detected in the three comparisons, respectively. DEGs with P < 0.05 and |FC| > 2 were used for functional enrichment analyses. For the S vs. H comparison, DEGs detected included CCL20, IL13 and MMP3, which are associated with the IL-17 signaling pathway. In the SM vs. HM and SMD vs. HMD comparisons, five (BLA-DQB, C1R, C2, FCGR1A, and KRT10) and six (BLA-DQB, C3AR1, CFI, FCAR, FCGR3A, and LOC10498484) genes, respectively, were involved in the S. aureus infection pathway. Conclusions Our study provides insights into the transcriptomic responses of bovine peripheral blood leukocytes across two generations of cattle naturally infected with S. aureus. The genes highlighted in this study could serve as expression biomarkers for mastitis and may also contain sequence variation that can be used for genetic improvement of dairy cattle for resilience to mastitis.

Transcriptome analysis reveals potential immune function-related regulatory genes/pathways of female Lubo goat submandibular glands at different developmental stages

“…Studies on immune function of submandibular glands have been formed in mice, rat, and human (Carpenter et al, 2004;Salo, Ylikoski & Uusitalo, 1993), however, data on goats are very scarce. Immune-related genes were identified through transcriptome analysis in siamese fighting fish, chicken, dairy cows and giant panda (Amparyup et al, 2020;Guo et al, 2020;Wu et al, 2020;Wang et al, 2020). To understand the pathways and key regulatory genes involved in the immune regulation-related functions of goat submandibular glands at different developmental stages, high-throughput transcriptome sequencing was used in the present study to detect gene expression levels in these glands in goats at three developmental stages.…”

Integrative Analysis of miRNA and mRNA Expression Profiles in Mammary Glands of Holstein Cows Artificially Infected with Staphylococcus aureus

“…To evaluate the reliability of the miRNA–mRNA interaction network, the DE miRNAs and DEGs ( p ≤ 0.05 and |log 2 FC| ≥ 2) obtained in this study were compared and taken the intersections with those from previous relevant studies [ 20 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 ].…”

Global transcriptomic profiles of circulating leucocytes in early lactation cows with clinical or subclinical mastitis

“…In response to mastitis, the SCC increases due to the in ux of immune cells, along with an in ammatory process. Previous studies have investigated circulating leukocyte gene expression in cows with mastitis induced by experimental infection with E. coli [37,27] or S. aureus [38], but information on leukocyte gene expression pro les in cows with naturally occurring subclinical mastitis are lacking. Subclinical mastitis has a higher prevalence and long term devastating effects as compared to clinical mastitis and is considered as the most economically important type of mastitis [2,39].…”