Periocular injection of MSC-Exo ameliorated uveitis in rats. (A) Both eyes of the immunized rats were injected periocularly with different doses of MSC-Exo (10, 20, 50, and 100 μg) or with an equal volume of PBS (control) on a daily basis for 7 consecutive days starting from the 9th day post immunization. B: 50 μg FIB-exo or an equal volume of PBS was administrated in the same way as above. Asterisks indicate the significant differences between control (black curve) and exosomes treated (blue curve), Values are expressed as the mean ± SD of six rats (12 eyes) per group. *P < 0.05.