Figure 7

Histological findings in peribronchial and perivascular tissues of the (a) control group, (b) OVA-only group, (c) S-SNP group, (d) M-SNP group and (e) P-SNP group. M-SNP, mesoporous silica nanoparticle; P-SNP, PEGylated silica nanoparticle; S-SNP, spherical silica nanoparticle.