Transcriptomes analysis of peripheral blood mononuclear cell revealed the immune heterogeneity of bTB at different stages

We investigated peripheral blood mononuclear cell (PBMC) transcriptomes in naturally M. bovis-infected cattle. PBMCs isolated from cattle with different infection statuses (i.e., nested PCR-positive (bTB PCR-P), nested PCR-negative (bTB PCR-N) M. bovis-infected cattle and healthy cattle) were treated with bovine purified protein derivative of bovine tuberculin (PPD-B) or phosphate-buffered saline (PBS) for 6 h. By RNA-Seq, we compared the transcriptomes of PPD-B-stimulated and -unstimulated (PBS-treated) PBMCs between the three groups. Numerous differentially expressed genes were identified following pair-wise comparison of different groups, with or without PPD-B stimulation (adjusted p < 0.05). RNA-seq data was confirmed by validating 14 known genes with qRT–PCR. Finally, data analysis revealed the immune heterogeneity of bTB at different stages which can improve the understanding of the molecular mechanisms in bTB progression. Overall design: PBMCs mRNA profiles of nested PCR-positive M. bovis-infected cattle, nested PCR-negative M. bovis-infected cattle and healthy cattle were generated by deep sequencing, in triplicate, treated with PPD-B and PBS, using an Illumina HiSeq 2000 system.