Figure 1.

Intradermal inoculation with LNPs induces robust inflammation

(A) Intradermal inoculation with LNP induced visible levels of inflammation. Pictures were taken 24 h after PBS or LNP injection.

(B) Skin samples from the mice injected with PBS or LNPs (2.5 μg/spot) were harvested at the indicated time points, analyzed by flow cytometry, and displayed as cell percentages.

(C) As in A, but LNPs with (iLNP) or without (nLNP) ionizable lipids were used. Unlike iLNPs the nLNPs induced no visible signs of inflammation.

(D) Skin samples from C were analyzed for leukocytic infiltration 24 h post-inoculation.

(E) Muscle samples from the mice injected with PBS or 10 μg LNPs were analyzed for neutrophil infiltration 24 h post-inoculation.

(F) The weight of muscle samples from E are shown. For all the charts the data were pooled from two separate experiments and displayed as percent ±SD. Each dot represents a separate animal. Student's two-tailed t test was used to determine the significance between naive and the experimental samples. ∗∗∗∗p < 0.0001, ∗∗∗p < 0.0005, ∗∗p < 0.005, ∗p < 0.05, ns = not significant. No significant differences were observed between samples harvested from naive or PBS-treated animals and are used interchangeably throughout the manuscript.

See also Figure S1.