Abstract
Purpose :
To investigate the pathogenic role of Demodex on hair follicle and meibomian gland in blepharitis.
Methods :
Eyelashes from 20 patients with Demodex blepharitis and 15 healthy volunteers, and eyelid tissues from 6 cadavers were studied. Apoptosis of hair follicles was determined by TUNEL assay. TUNEL and Ki67 double staining was performed on eyelid cross-sections. Immunostaining of K10, CD11c and MAC387 was also performed on eyelid tissues.
Results :
The apoptotic cells increased and Ki67 expression decreased in hair follicle and surrounding tissue in Demodex-positive group. K10 expression significantly expanded in hair follicle and meibomian gland, suggesting abnormal differentiation. Demodex-positive tissues were infiltrated with dendritic cells and macrophages, as evidenced by prominent CD11c and MAC387 expression, indicating excessive immune response in Demodex blepharitis.
Conclusions :
Demodex play a pathogenic role in blepharitis. The pathogenic mechanism may be accomplished by interrupting the hair follicle turnover, promoting apoptosis, altering the epithelial keratin phenotype of hair follicles and meibomian gland, and abnormal immune response around the hair follicle.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.