TNF and infectious disease: Notably, these pathways, such as the TNF signaling pathway, MAPK signaling pathway, and cytokine-cytokine receptor interactions, play major roles in the host inflammatory response to numerous infectious diseases (Benedict, Banks & Ware, 2003; Gong et al., 2011; Li et al., 2011; Maegraith & Harinasuta, 1953), suggesting that swine lncRNAs may contribute to host inflammation during PCV2 infection.