IFN-b priming exacerbates LPS-driven proinflammatory cytokines in macrophages.. Mus musculus

Purpose: We characterize the changes global expression profile in peripheral macrophages induced by LPS, IFN-b, and IFN-B+LPS treatment, using bulk RNA-sequencing. Methods: mRNA profiles of bulk macrophages obtained from WT mice following treatment with either saline, IFN-b, LPS, or IFN-b+LPS. Each treatment was performed in triplicate, and RNA-sequencing was performed on the Illumina 2500. Reads passing quality metric were aligned to the mm10 genome using annotations produced by ENSEMBL, and were analyzed at the transcript level using one-way ANOVA and fold change requirements. Results: We mapped approximately 20 million reads per sample to the mm10 genome, yielding 11385 reasonably-expressed transcripts. We identified 4372 transcripts with a p-value2 when compared between LPS v NS, IFNb v NS, and LPS+IFNb v NS. Of these, we identified 142 genes where priming by IFNb+LPS augmented the changes in expression induced by LPS or IFNb independently. This gene set indicated that IFNb exacerbates LPS_driven proinflammatory cytokin production. Conclusion: Here we show that IFNb priming sensitizes to TLD-driven inflammation through LPS stimulation. Overall design: Our study characterizes the transcriptional changes induced by LPS, IFNb, and LPS+IFNb through RNAsequencing of peripheral macrophages. Our results identify the augmentation of LPS-induced pathways through priming by IFNb.