Figure 7.

circSnx5-Overexpressing DCs Reduces Cardiac Injury and Inflammation in Experimental Autoimmune Myocarditis

(A) Schematic diagram of the experimental design. Experimental autoimmune myocarditis (EAM) was induced by injecting 100 μg of cardiac αMHC emulsified in CFA on days 0 and 7. circSnx5-DCs or LPS-DCs were injected into mice on days 8 and 15. Mice were killed at days 21 or 45 after the first immunization. (B and C) Representative (B) H&E staining of the hearts from EAM mice, LPS-DC mice, or circSnx5-DC mice at the peak of inflammation (day 21). Scale bars, 100 μm. (C) Inflammation was scored by percentage of myocardium infiltrated with mononuclear cells (n = 6 biological replicates). (D and E) Immunohistochemical labeling for Foxp3 (D) and counts of infiltrating Foxp3⁺ cells (E) in hearts harvested from different groups. Scale bars, 50 μm (n = 6 biological replicates). (F) Serum cardiac troponin-I (cTnI) levels in three different groups of mice were measured by ELISA on day 21 (n = 6 biological replicates). (G and H) Expression of CD4⁺CD25⁺Foxp3⁺ Tregs in splenic T cells was assessed by flow cytometry in three different groups on day 21 (H) and are shown as percentages (G). n = 6 biological replicates. (I) Images of hearts from three different mice groups at day 45. Scale bars, 1 cm. (J and K) Echocardiographic analysis images of left ventricular (LV) M-mode echocardiograms 45 days after injection. Left ventricular ejection fraction (LVEF) (J) and LV internal diastolic diameter (LVIDD) (K) are shown. circDCs, circSnx5-overexpression DCs (n = 6 biological replicates). Data are shown as mean ± SD. ∗p < 0.05, ∗∗p < 0.01, by Student’s t test.