Papillary vitreous detachment as a possible accomplice in non-arteritic anterior ischaemic optic neuropathy.

AIM: To evaluate the role of papillary vitreous detachment in the pathogenesis of non-arteritic anterior ischaemic optic neuropathy (NAION) by comparing the features of vitreopapillary interface between NAION patients and normal individuals. METHODS: This study included 22 acute NAION patients (25 eyes), 21 non-acute NAION patients (23 eyes) and 23 normal individuals (34 eyes). All study participants underwent swept-source optical coherence tomography to assess the vitreopapillary interface, peripapillary wrinkles and peripapillary superficial vessel protrusion. The statistical correlations between peripapillary superficial vessel protrusion measurements and NAION were analysed. Two NAION patients underwent standard pars plana vitrectomy. RESULTS: Incomplete papillary vitreous detachment was noted in all acute NAION patients. The prevalence of peripapillary wrinkles was 68% (17/25), 30% (7/23) and 0% (0/34), and the prevalence of peripapillary superficial vessel protrusion was 44% (11/25), 91% (21/23) and 0% (0/34) in the acute, non-acute NAION and control groups, respectively. The prevalence of peripapillary superficial vessel protrusion was 88.9% in the eyes without retinal nerve fibre layer thinning. Furthermore, the number of peripapillary superficial vessel protrusions in the superior quadrant was significantly higher than that in the other quadrants in eyes with NAION, consistent with the more damaged visual field defect regions. Peripapillary wrinkles and visual field defects in two patients with NAION were significantly attenuated within 1 week and 1 month after the release of vitreous connections, respectively. CONCLUSION: Peripapillary wrinkles and superficial vessel protrusion may be signs of papillary vitreous detachment-related traction in NAION. Papillary vitreous detachment may play an important role in NAION pathogenesis.

CD73 Pathway Contributes to the Immunosuppressive Ability of Mesenchymal Stem Cells in Intraocular Autoimmune Responses.

Mesenchymal stem cells (MSCs) exhibit a potent immunomodulatory capacity and have been applied to treat diseases such as graft versus host disease and severe autoimmune diseases. However, the mechanism underlying their immunosuppressive effect is not yet completely understood. Here, we investigated the role of the CD73/adenosine pathway in immune modulation by MSCs using a mouse model of experimental autoimmune uveitis (EAU). Moreover, we examined the in vitro modulatory effect of MSCs mediated through the CD73/adenosine pathway in human and mouse T cells. We found that the severity of EAU was significantly attenuated by MSCs; however, most therapeutic effects of MSCs were lost by pretreatment with a CD73 inhibitor. The inhibitory mechanism of MSCs might be contributed by CD73 on MSCs that cooperated with CD39 and CD73 on activated T cells to produce adenosine, resulting in inhibition of T-cell proliferation. Furthermore, MSCs increased the expression of CD73 on CD4(+) T cells, and transforming growth factor-ß1 (TGF-ß1) was the only tested cytokine that contributed to upregulation of CD73. Hence, our study demonstrates that the CD73/adenosine pathway involves the immunomodulatory function of MSCs in autoimmune responses.