Inhibition of exosomes coupling with CVB3 attenuated the pathogenetic events <i>in vivo</i>.

(A and B) The exosomes isolated from wild-type (WT) or Rab27a-KO mice of serum was quantified using NTA(A) and western blot(B). Each group contained 5 mice. (C, D and E) Real-time PCR data for the comparison of CVB3 RNA expression level in splenic T(C), splenic B(D) and monocytes(E) cells in WT or Rab27a-KO mouse at various time points. Six weeks-old of Rab27a-KO mice or WT mice were orally inoculated after fasting at 5×106 TCID50 per mouse. n = 5 biologically independent animals per group. (F and G) The percentage of CVB3-infected splenic T(F) and splenic B(G) cells were determined by flow cytometric analysis at indicative time points. Cells were stained with anti-CVB3 and Alexa Fluor 488-conjugated anti-mouse IgG antibody. (H, I and J) Real-time PCR analysis of inflammatory factors expression in cardiac tissue of CVB3-infected mice or mock mice at various time points. (K and L) Left ventricular ejection fraction(LVEF) and left ventricular fractional shortening(LVFS) of CVB3-infected mice was measured though M-mode echocardiography. Rab27a-KO mice or WT mice(n = 5) were orally inoculated at 5×106 TCID50 per mouse and the echocardiographic data was recorded at 3 day post-infection. (M) Levels of serum neutralizing antibody(NAb) titer in CVB3-infected mice. Different symbols correspond to independent experiments. (N) Cellular immune responses of CVB3-infected WT or Rab27a-KO mice was determined by IFN-γ ELISpot assay at 2, 4 and 6 day post-infection. (O and P) The body weight change (O) and survival rate (P) were respectively monitored daily until 14 day post-infection. All the data are shown as mean ± SD of three independent experiments. (*p<0.05, **p<0.01,***p<0.001).