Fig. 6

Exposure of latently infected mice to NP produces a metabolite composition in the lung resembling the one seen in acute virus infection: PCA was used to compare chemical similarities in the examined groups, and significant observations on PC-scores are shown in panel a. Mass difference networks were created to visualize the chemical similarity of the combined virus plus CNP treatment and the control groups. Figure 6 b gives an overview of the compound classes shown in panels c-e. The mass difference networks of the two control groups “virus alone” and “CNP alone” appeared exactly the same but proved to be entirely contraindicative once performed separately with compounds that were upregulated in one group being downregulated in the other group c. Green color stands for unchanged compounds. Blue color represents metabolites that are upregulated in “virus 29d” and downregulated in “CNP 24 h”. Red color depicts metabolites that are upregulated in “CNP 24 h” and downregulated in “virus 29d”. The pattern observed in “virus 28d + CNP 24 h” d showed upregulation of specifically one compound group. This profoundly resembles the pattern seen in acute virus infection e. In panels d and e, blue color stands for downregulated metabolites while red color depicts upregulated ones. The most pronounced changes in the metabolic profile were seen in the group of phospholipids. All data are obtained from 3 mice per group