Changes in plasma concentration of different soluble factors over time after inoculation with SIVmac251 in untreated and ART-treated macaques. Untreated macaques: (A) IFN-I, (B) IL-18, (C) IFN-γ, (D) kynurenine, (E) tryptophan, (F) kynurenine:tryptophan ratio. Solid gray lines: macaques infected with 50 AID₅₀; solid black lines: macaques infected with 5000 AID₅₀. Dotted lines in panels A to F: median plasma viral load of the 50 AID₅₀ group (gray) and 5000 AID₅₀ group (black). Macaques that received post-exposure ART: (G) IFN-I, (H) IL-18, (I) IFN-γ, (J) tryptophan and kynurenine ratio. Dotted lines in panels G to J: median plasma viral load of the 50 AID₅₀+ART group. Duration of ART treatment is indicated by a gray horizontal bar.