Objective:To observe the changes of varicella zoster virus (VZV)-DNA load in aqueous humour samples in VZV-induced acute retinal necrosis (ARN) in the early stages of antiviral treatment.Methods:A retrospective observational clinical study. From April 2016 to April 2018, 24 patients with 24 eyes of VZV-induced ARN who were diagnosed by Department of Ophthalmology, Eye and ENT Hospital of Fudan University and received complete aqueous humor sampling were included in the study. Among them, there were 13 males with 13 eyes, 11 females with 11 eyes; 12 left eyes and 12 right eyes; the age was 52.0±9.5 years old (39-71 years old). The time from the onset of ocular symptoms to the diagnosis of ARN was 16.6±6.1 days (7-30 days). Best-corrected visual acuity (BCVA) and ultra-wide-field fundus imaging were performed in all affected eyes. The BCVA examination was carried out using the Snellen visual acuity chart, which was converted into the logarithm of the minimum angle of resolution (logMAR) visual acuity. All patients were given intravitreal injection of 40 mg/ml ganciclovir 0.1 ml (including 4 mg of ganciclovir), 2 times a week, until the active necrotizing retinal lesions subsided, at most after the diagnosis 4 weeks, with a maximum of 9 injections. The follow-up period was 12.8±5.6 months. The aqueous humor samples were collected at presentation and 4, 7, 14, 21, 28 days after the initiation of antiviral therapy, and the VZV-DNA load was detected by real-time quantitative polymerase chain reaction. A plateau phase and a logarithmic reduction phase of the DNA load changes were observed after antiviral treatment began. Wilcoxon rank sum test was used to compare and analyze the differences in BCVA between the eyes at baseline and last follow-up.Results:The mean viral load at presentation was 8.6×10 7±1.3×10 8 copies/ml. The initial plateau phase last for an average of 7.4±2.4 days. In the following logarithmic reduction phase, the mean slope of the decline in viral load was -0.13±0.04 log/day, and the expected time for half reduction of the initial viral load was 2.5±0.7 days. After 28 days antiviral treatment, the viral load decreased to 1.7×10 5±1.8×10 5 copies/ml. In the course of the disease, rhegmatogenous retinal detachment occurred in 16 eyes. Before treatment and at the last follow-up, the logMAR BCVA of the affected eye was 1.1±0.6 and 0.8±0.7, respectively. The results of correlation analysis showed that the logMAR BCVA at the last follow-up was correlated with the initial VZV-DNA load ( r=0.467, P=0.033). Conclusion:The VZV-DNA load in the aqueous humor of eyes with VZV-induced ARN is significantly decreased after antiviral treatment, which is closely related to the clinical process of ARN.

Objective: To investigate the protective effect of human umbilical cord mesenchymal stem cells (UCMSCs) on light-damaged retinal pigment epithelial (RPE) cells in vitro. Methods: Human UCMSCs were cultured, and then identified by flow cytometry.Human RPE cells were isolated and cultured, and then the model of light-damaged RPE cells was prepared.The noncontact co-culture system of light-damaged RPE cells and UCMSCs was established by Transwell chamber.RPE cells were divided into normal control group, model control group and UCMSCs co-culture group.RPE cells in the normal control group were not treated.RPE cells in the model control group were treated with blue light to induce RPE cell damage.Co-culture system of light-damaged RPE cells and UCMSCs was established in the UCMSCs co-culture group.The proliferative ability of RPE cells was measured by methyl thiazolyl tetrazolium (MTT) assay at 24 hours and 48 hours after co-culture.ELISA kits were used to quantitatively measure the levels of pigment epithelium-derived factor (PEDF) and basic fibroblast growth factor (bFGF) in the culture supernatant at 48 hours after co-culture.And the photoreceptor outer segments (POS) phagocytosis assay of RPE cells was also conducted. Results: UCMSCs displayed spindle-shaped morphology, positively expressed CD29, CD44, CD90 and CD105, while negatively expressed CD34 and CD45.RPE cells were polygonal in morphology and positive for the specific marker RPE65 protein.The proliferative ability(A value) of RPE cells in the three groups at different timepoints were significantly different (F_group=132.388, P=0.000; F_time=231.440, P=0.000), the A values of RPE cells in model control group and UCMSCs co-culture group were significantly lower than that in the normal control group, the A value of RPE cells in UCMSCs co-culture group was significantly higher than that in the model control group, and the differences were statistically significant both at 24 hours and 48 hours after co-culture (all at P<0.01). POS phagocytosis test showed that there was a significant difference in the average number of POS particles phagocytized by RPE cells among the three groups(F=28.087, P=0.000). The average number of POS particles phagocytized by RPE cells in model control group was significantly lower than that in normal control group, and the average number of POS particles phagocytized by RPE cells in UCMSCs co-culture group was significantly more than that in model control group (all at P<0.01). ELISA showed that the concentrations of PEDF in RPE cell supernatant of normal control group, model control group and UCMSCs co-culture group were (18.8±1.9), (10.0±1.7) and (20.2±6.0)ng/ml, respectively.The concentrations of bFGF in RPE cell supernatant were (25.2±1.5), (26.3±3.6) and (61.9±14.3)pg/ml, respectively.There were significant differences in PEDF and bFGF concentrations among the three groups (F=8.654, P=0.008; F=23.698, P=0.000). The concentration of PEDF in the model control group was significantly lower than that in the normal control group, and the concentration of PEDF in the UCMSCs co-culture group was significantly higher than that in the model control group (all at P<0.01). The concentration of bFGF in UCMSCs co-culture group was significantly higher than that in the normal control group and model control group (all at P<0.01). Conclusions Cocultivation with UCMSCs can improve the proliferation ability and phagocytosis function of light-damaged RPE cells, and promote the secretion of PEDF by RPE cells.UCMSCs may protect RPE cells from light damage through paracrine secretion of bFGF.