Figure 4.

Engineered IDO1 ameliorates rat CIA

(A) Sprague-Dawley rats were injected intradermally with type II chicken collagen/IFA on day 0 to induce collagen-induced arthritis (CIA). Rats were treated with 0.5 mg/kg LNP A-formulated mRNA i.v.

(B–E) For prophylactic dosing, administration of mRNA occurred weekly with dosing on days 0, 7, and 14.

(F–I) To dose therapeutically, rats were injected weekly starting on day 0, 3, 7, 10, or 14 as indicated in the figure legend.

(B and F) Mean clinical score and (C and G) percentage of disease-free animals were calculated. (D and H) Mean disease intensity and (E and I) mean peak score were calculated from day 10 to 21. (B and F) Data are mean and SEM of 5–8 rats/group and representative of 3 similar experiments. Significance was determined compared to dead SRC.IDO by two-way ANOVA with secondary Dunnett’s multiple comparisons tests. ∗p < 0.05, ∗∗p < 0.005, ∗∗∗p < 0.0005, and #p < 0.0001. (C and G) Significance was determined compared to dead SRC.IDO by log-rank (Mantel-Cox) test. ∗∗p < 0.01. (D, E, H, and I) Data are individual rats and median. Significance was determined compared to dead SRC.IDO by one-way ANOVA and secondary Dunnett’s multiple comparisons tests. ∗∗∗∗p < 0.0001.