Ectopic insert-dependent neuronal expression of GFAP promoter-driven AAV constructs in adult mouse retina.

Direct reprogramming of retinal Müller glia is a promising avenue for replacing photoreceptors and retinal ganglion cells lost to retinal dystrophies. However, questions have recently been raised about the accuracy of studies claiming efficient glia-to-neuron reprogramming in retina that were conducted using GFAP mini promoter-driven adeno-associated virus (AAV) vectors. In this study, we have addressed these questions using GFAP mini promoter-driven AAV constructs to simultaneously overexpress the mCherry reporter and candidate transcription factors predicted to induce glia-to-neuron conversion, in combination with prospective genetic labeling of retinal Müller glia using inducible Cre-dependent GFP reporters.

Genetic loss of function of Ptbp1 does not induce glia-to-neuron conversion in retina.

Direct reprogramming of glia into neurons is a potentially promising approach for the replacement of neurons lost to injury or neurodegenerative disorders. Knockdown of the polypyrimidine tract-binding protein Ptbp1 has been recently reported to induce efficient conversion of retinal Mϋller glia into functional neurons. Here, we use a combination of genetic lineage tracing, single-cell RNA sequencing (scRNA-seq), and electroretinogram analysis to show that selective induction of either heterozygous or homozygous loss-of-function mutants of Ptbp1 in adult retinal Mϋller glia does not lead to any detectable level of neuronal conversion.

Focal Choroidal Elevations: Localized Pigment Epithelial Contour Alterations due to Isolated Choroidal Vessels.

Purpose: The objective of this case series was to describe the clinical and imaging features of focal choroidal elevations (FCE), which are chorioretinal contour changes induced by individual choroidal vessels within an overall thin-appearing choroid.

Methods: A total of 787 enhanced depth imaging (EDI) spectral domain optical coherence tomography (SD-OCT) patient images were initially screened for the presence of FCE. Prospective imaging analysis of 38 patients with FCE was done.

Inner Nuclear Layer Cystic Changes in Phakic Fellow Eyes of Patients With Acute Pseudophakic Cystoid Macular Edema.

Improvements in retinal imaging have recently elucidated structural patterns in the development of macular edema, particularly involving the inner nuclear layer. Here, the authors describe two cases of isolated inner nuclear layer cystic changes in the phakic fellow eye of patients with pseudophakic cystoid macular edema. Both cases improved with treatment of their fellow eye and resolution of contralateral macular edema.

Morphology of Peripheral Vitreoretinal Interface Abnormalities Imaged with Spectral Domain Optical Coherence Tomography.

The objective of this study is to describe the clinical utility and morphologic characteristics of peripheral vitreoretinal interface abnormalities with spectral domain optical coherence tomography (SD-OCT). A prospective imaging analysis of 43 patients with peripheral vitreoretinal interface abnormalities seen on binocular indirect examination with scleral indentation was done. SD-OCT was evaluated for image quality and structural findings.