Objective      To investigate the in vitro properties of nanoparticles containing thymosin β4 chitosan (Tβ4/CS)

and determine its effect on the repair of rabbit corneal wound by regulating the expression of nuclear transcription factor NF-κB.       Methods      The ionotropic gelation was employed to produce Tβ4/CS nanoparticles. Then particle size

zeta potential

encapsulation efficiency and release in vitro were studied. Tβ4/CS nanoparticle suspension drops

2.0 mg/L

was use

d to drop on the eyes of the rabbit for the toxicity of the particles

while the right eyes were set as normal control. HE staining was used to stain the ocular surface tissue

to observe whether there exists ocular surface toxicity or not. In rabbit corneal trauma model

all rabbits’ right eyes were set as the experimental subject

and the rabbits were divided into Tβ4/CS nanoparticle group (A)

Tβ4 group (B) and control group (C)

with 20 animals in each group. General observation and HE staining were carried in the corneal wound on 1

3

7

and 14 d after treatment

and RT-PCR was used to detect the expression of corneal nuclear transcription factor NF-κB.       Results      Tβ4/CS nanoparticles were mostly in round shape

in a diameter of 354.0±1.6 nm

with a zeta potential of 22.5±0.7 mV

and encapsulation efficiency of (76.2±2.8)%. The produced Tβ4/CS nanoparticles were stable

with a sustained-released function. The toxicity test indicated that Tβ4/CS nanoparticles eye drops

2.0 mg/L

were not harmful for the rabbit eyelids

conjunctiva

and cornea. The Tβ4/CS nanoparticles down-regulated the expression of NF-κB in rabbit traumatic corneal to promote corneal repair significantly

at each time point than the other 2 groups (

P

0.01).       Conclusion      The thymosin β4 chitosan nanoparticles eye drops can be used to promote corneal repair in the rabbit traumatic corneal by down-regulating NF-κB

without any harm to the ocular surface.