We evaluated ocular surface alterations in allogeneic hematopoietic stem cell transplantation (HSCT) recipients with or without chronic GVHD-related dry eye in a prospective study. Fifty eyes of 25 post-HSCT patients and 28 eyes of 14 age-matched healthy controls were included. Meibomian gland (MG) obstruction, tear evaporation rate, corneal sensitivity (CS), Schirmer test-I, tear break-up time (BUT) and ocular surface vital staining were examined. Conjunctival impression and brush cytology specimens were collected to evaluate the goblet cell density (GCD) and the inflammatory cell numbers. Obvious MG obstruction, decreased CS and enhanced tear evaporation rate were found in post-HSCT patients compared with normal controls. In addition, decreased conjunctival GCD, increased conjunctival squamous metaplasia and inflammatory cells were noted in cGVHD-related dry eyes compared with normal controls and post-HSCT without dry eye subjects. Furthermore, the conjunctival inflammatory cells were significantly higher in severe dry eyes compared with mild dry eyes (P ¼ 0.03). We found comprehensive ocular surface alteration in post-HSCT patients, regardless of whether they had cGVHD-related dry eye or not. The results suggest that the extent of inflammatory process seems to have a pivotal role in the outcome of the cGVHD-related dry eye.

We investigated the effect of 0.05% topical cyclosporine (Cys) on the ocular surface and tear functions in dry eye patients with chronic GVHD (cGVHD) in a prospective comparative study. Thirty eyes of 15 patients refractory to baseline treatment were recruited and the patients assigned for topical Cys treatment group (14 eyes of 7 patients) and control group (12 eyes of 6 patients) respectively. Two patients dropped out because of intolerable irritation while using topical Cys eye drops. Visual analog scale symptom scores, corneal sensitivity, Schirmer I test value, tear film break-up time (TBUT), tear evaporation rate and ocular surface vital staining scores were recorded at baseline and at the end of the following one month. Conjunctival impression and brush cytology were performed before and after the treatment. After topical Cys treatment, significant improvements were found in symptom scores, corneal sensitivity, tear evaporation rate, TBUT, vital staining scores, goblet cells density, conjunctival squamous metaplasia grade, inflammatory cell numbers and the MUC5AC expression. Our study suggests that 0.05% topical Cys may be an effective treatment for dry eye patients with cGVHD. The improvements in the ocular surface and tear functions resulted presumably from the decreased inflammation, increased goblet cell density and MUC5AC mRNA expression.

Sensorineural hearing loss (SNHL) is one of the most common sensory defects in humans. Hair cells are vulnerable to various ototoxic insults. Effective prevention of hair cell loss remains an unmet medical need. Apoptotic hair cell death, which involves active regulation of transcription, accounts for the majority of aminoglycoside-induced hair cells loss. As one of the important epigenetic covalent modifications, histone methylation is involved in the regulation of gene expression, development and reaction to injury. In particular, H3K9 dimethylation (H3K9me2) is critical for euchromatin gene silencing. In the present study, we examined the roles of two highly homologous histone methyltransfereases responsible for this modification, G9a/G9a-like protein (GLP), in the reaction to aminoglycoside-induced hair cell damage. We observed a rapid increase of H3K9me2 upon hair cell damage in organotypic cochlear cultures. Treatment with the G9a/GLP-specific inhibitors, BIX01294 or UNC0638, reduced the level of H3K9me2 and prevented hair cells from death. Local delivery of BIX01294 also prevented neomycin-induced in vivo auditory hair cell loss in the organ of Corti in a mouse damage model. It is unlikely that BIX01294 functions through blocking aminoglycoside absorption as it does not interfere with aminoglycoside uptaking by hair cells in the organotypic cochlear cultures. Our data revealed a novel role of histone methylation in otoprotection, which is of potential therapeutic value for SNHL management.