Publications

2019

Whitman M, Miyake N, Nguyen E, Bell J, Matos Ruiz P, Chan WM, Di Gioia SA, Mukherjee N, Barry B, Bosley, Khan A, Engle E. Decreased ACKR3 (CXCR7) function causes oculomotor synkinesis in mice and humans. Hum Mol Genet. 2019;28(18):3113–3125.
Oculomotor synkinesis is the involuntary movement of the eyes or eyelids with a voluntary attempt at a different movement. The chemokine receptor CXCR4 and its ligand CXCL12 regulate oculomotor nerve development; mice with loss of either molecule have oculomotor synkinesis. In a consanguineous family with congenital ptosis and elevation of the ptotic eyelid with ipsilateral abduction, we identified a co-segregating homozygous missense variant (c.772G>A) in ACKR3, which encodes an atypical chemokine receptor that binds CXCL12 and functions as a scavenger receptor, regulating levels of CXCL12 available for CXCR4 signaling. The mutant protein (p.V258M) is expressed and traffics to the cell surface but has a lower binding affinity for CXCL12. Mice with loss of Ackr3 have variable phenotypes that include misrouting of the oculomotor and abducens nerves. All embryos show oculomotor nerve misrouting, ranging from complete misprojection in the midbrain, to aberrant peripheral branching, to a thin nerve, which aberrantly innervates the lateral rectus (as seen in Duane syndrome). The abducens nerve phenotype ranges from complete absence, to aberrant projections within the orbit, to a normal trajectory. Loss of ACKR3 in the midbrain leads to downregulation of CXCR4 protein, consistent with reports that excess CXCL12 causes ligand-induced degradation of CXCR4. Correspondingly, excess CXCL12 applied to ex vivo oculomotor slices causes axon misrouting, similar to inhibition of CXCR4. Thus, ACKR3, through its regulation of CXCL12 levels, is an important regulator of axon guidance in the oculomotor system; complete loss causes oculomotor synkinesis in mice, while reduced function causes oculomotor synkinesis in humans.
Charles N, Jakobiec F, Ma L, Belinsky I. Angiofibroma of the Eyelid: A Rare Clinical and Histologic Variant. Ophthalmic Plast Reconstr Surg. 2019;35(4):e199-e102.
A flesh-colored, supraciliary lesion of the left upper eyelid in a 47-year-old man was excised for cosmetic reasons. Histopathology and immunohistochemistry demonstrated CD34-positive benign spindle cells, factor XIIIa-positive dendritic cells, and CD163-positive histiocytes, all dispersed within a diffuse collagenous background. Prominent loose perivascular cuffs of fibroblastic cells and collagen surrounded small blood vessels. Interpreted as an angiofibroma, the histopathology bore resemblance to that of a single previously-reported forearm lesion termed a "dermal fibroma with a distinctive perivascular cell arrangement." The lesion represents the first eyelid example of an unusual variant of angiofibroma.
Foulsham W, Mittal S, Nakao T, Coco G, Taketani Y, Chauhan S, Dana R. The purinergic receptor antagonist oxidized adenosine triphosphate suppresses immune-mediated corneal allograft rejection. Sci Rep. 2019;9(1):8617.
Adenosine triphosphate (ATP) is released into the extracellular environment during transplantation, and acts via purinergic receptors to amplify the alloimmune response. Here, using a well-established murine model of allogeneic corneal transplantation, we investigated the immunomodulatory mechanisms of the purinergic receptor antagonist oxidized ATP (oATP). Corneal transplantation was performed using C57BL/6 donors and BALB/c hosts. oATP or sterile saline was administered via intraperitoneal injection for 2 weeks postoperatively. Frequencies of CD45 leukocytes, CD11bMHCII antigen presenting cells (APCs), CD4IFN-γ effector Th1 cells and CD4Foxp3 regulatory T cells (Tregs) were evaluated by flow cytometry. Slit-lamp microscopy was performed weekly for 8 weeks to evaluate graft opacity and determine transplant rejection. Treatment with oATP was shown to significantly reduce graft infiltration of CD45 leukocytes, decrease APC maturation and suppress effector Th1 cell generation relative to saline-treated control. No difference in Treg frequencies or Foxp3 expression was observed between the oATP-treated and control groups. Finally, oATP treatment was shown to reduce graft opacity and increase graft survival. This report demonstrates that oATP limits the alloimmune response by regulating APC maturation and suppressing the generation of alloreactive Th1 immunity.
Perepelkina T, Kegeles E, Baranov P. Optimized conditions and use of synthetic matrix for retinal differentiation from pluripotent cells. Tissue Eng Part C Methods. 2019;
PURPOSE: Since it was first introduced in 2011, three-dimensional "Sasai" method for retinal differentiation became a strategy of choice for retinal tissue and neuron production. It is based on the recapitulation of retinal development and requires several stages: aggregate formation, neuroectoderm induction, and eye field induction, followed by retinal maturation. In order to achieve the consistency of retinal differentiation needed for drug discovery and cell transplantation we have attempted to improve spheroid formation as well as approach xeno-free conditions. METHODS: In this study we compared the effect of cell culture plate shape and material, medium viscosity, lipid and bovine serum albumin concentrations on aggregate formation from mouse embryonic stem cells. We have also assessed the possibility of substituting Matrigel with the synthetic vitronectin-mimicking oligopeptide. RX-GFP mES cell line used for experiments. The dose-response of synthetic ECM has been assessed and quantified by live fluorescence microscopy, immunohistochemistry, flow cytometry and qPCR for early retinal development genes (Rx, Pax6, Lhx2, Sox2, Six6). RESULTS: The comparison of seeding conditions at 24hr. post seeding showed the dose-dependent effects of lipids (lipids concentration of 2% resulted in 100% efficiency of aggregate formation and significant increase in size to 532.8 ± 31.87um, p< 0.05); and viscosity (methylcellulose concentration of 0.06% in OV medium showed 100% efficiency and increase in aggregate size 532±19.23 um, p<0.01). The addition of synthetic matrix resulted in retinal differentiation (34.47% of RX as detected by flow cytometry compared to 33.8%, observed with Matrigel). The early retinal genes expression at day 7 was confirmed by qPCR. CONCLUSIONS: We present the optimized conditions for 3D retinal differentiation including the option of xeno-free extracellular matrix. These defined medium conditions significantly decrease the variability within and between batches and allow substantial scale up of retinal tissue and cell production for drug discovery, disease modeling and transplantation purposes.
An D, Fujiki R, Iannitelli D, Smerdon J, Maity S, Rose M, Gelber A, Wanaselja E, Yagudayeva I, Lee J, Vogel C, Wichterle H, Engle E, Mazzoni EO. Stem cell-derived cranial and spinal motor neurons reveal proteostatic differences between ALS resistant and sensitive motor neurons. Elife. 2019;8.
In amyotrophic lateral sclerosis (ALS) spinal motor neurons (SpMN) progressively degenerate while a subset of cranial motor neurons (CrMN) are spared until late stages of the disease. Using a rapid and efficient protocol to differentiate mouse embryonic stem cells (ESC) to SpMNs and CrMNs, we now report that ESC-derived CrMNs accumulate less human (h)SOD1 and insoluble p62 than SpMNs over time. ESC-derived CrMNs have higher proteasome activity to degrade misfolded proteins and are intrinsically more resistant to chemically-induced proteostatic stress than SpMNs. Chemical and genetic activation of the proteasome rescues SpMN sensitivity to proteostatic stress. In agreement, the hSOD1 G93A mouse model reveals that ALS-resistant CrMNs accumulate less insoluble hSOD1 and p62-containing inclusions than SpMNs. Primary-derived ALS-resistant CrMNs are also more resistant than SpMNs to proteostatic stress. Thus, an ESC-based platform has identified a superior capacity to maintain a healthy proteome as a possible mechanism to resist ALS-induced neurodegeneration.
This article aimed to characterize, compare, and contrast the management of isolated orbital floor fractures among oculofacial and facial plastic surgeons in the United States. An anonymous 17-question multiple-choice web-based survey was distributed to all 590 members of the American Society of Ophthalmic Plastic and Reconstructive Surgery (ASOPRS) and all 1,300 members of the American Academy of Facial Plastic and Reconstructive Surgery (AAFPRS) using each society's email database from November 2016 to January 2017. Two-hundred twenty-five oculofacial and 135 facial plastic surgeons completed the survey. The most important indications for surgery among both oculofacial and facial plastic surgeons were motility restriction, enophthalmos, and diplopia at 2 weeks. The most common preferred time to surgical intervention was 8 to 14 days; however, facial plastic surgeons were more likely to operate after 4 to 7 days (  < 0.001). The most common choices of orbital implant material were porous polyethylene and porous polyethylene plus titanium for both oculofacial and facial plastic surgeons, nylon for oculofacial surgeons, and titanium for facial plastic surgeons. The majority rarely/never used intraoperative computed tomography imaging or navigation. Facial plastic surgeons were more likely to perform postoperative imaging (  < 0.001). We report results of the first survey of isolated orbital floor fracture management among oculofacial and facial plastic surgeons in the United States. This survey characterizes practice patterns and areas of similarities/differences among oculofacial and facial plastic surgeons in the management of isolated orbital floor fractures, which may help define the current standard of care.
Liu CH, Wang Z, Huang S, Sun Y, Chen J. MicroRNA-145 Regulates Pathological Retinal Angiogenesis by Suppression of TMOD3. Mol Ther Nucleic Acids. 2019;16:335–347.
Pathological angiogenesis is a hallmark of various vascular diseases, including vascular eye disorders. Dysregulation of microRNAs (miRNAs), a group of small regulatory RNAs, has been implicated in the regulation of ocular neovascularization. This study investigated the specific role of microRNA-145 (miR-145) in regulating vascular endothelial cell (EC) function and pathological ocular angiogenesis in a mouse model of oxygen-induced retinopathy (OIR). Expression of miR-145 was significantly upregulated in OIR mouse retinas compared with room air controls. Treatment with synthetic miR-145 inhibitors drastically decreased levels of pathological neovascularization in OIR, without substantially affecting normal developmental angiogenesis. In cultured human retinal ECs, treatment with miR-145 mimics significantly increased the EC angiogenic function, including proliferation, migration, and tubular formation, whereas miR-145 inhibitors attenuated in vitro angiogenesis. Tropomodulin3 (TMOD3), an actin-capping protein, is a direct miR-145 target and is downregulated in OIR retinas. Treatment with miR-145 mimic led to TMOD3 inhibition, altered actin cytoskeletal architecture, and elongation of ECs. Moreover, inhibition of TMOD3 promoted EC angiogenic function and pathological neovascularization in OIR and abolished the vascular effects of miR-145 inhibitors in vitro and in vivo. Overall, our findings indicate that miR-145 is a novel regulator of TMOD3-dependent cytoskeletal architecture and pathological angiogenesis and a potential target for development of treatments for neovascular eye disorders.
Werner A, Shen L. A Review of OCT Angiography in Glaucoma. Semin Ophthalmol. 2019;:1–8.
There is growing evidence that vascular dysfunction plays a role in the pathogenesis of glaucoma. The details of this relationship have remained elusive partially due to limitations in our ability to assess blood flow in the optic nerve. Optical coherence tomography angiography (OCTA) has emerged as a promising new technology well positioned to become the first clinically suitable test of optic nerve perfusion. OCTA uses the motion of red blood cells as an intrinsic contrast agent to create reproducible images of microvascular networks rapidly and non-invasively. A significant body of research regarding the use of OCTA in glaucoma has emerged in recent years. This review aims to provide an overview of the basic principles underlying OCTA technology, summarize the current literature regarding the application of OCTA in the management of glaucoma, and address the role of OCTA in explicating the vascular pathogenesis of glaucoma.
Siddiqui Y, Yin J. Anterior Segment Applications of Optical Coherence Tomography Angiography. Semin Ophthalmol. 2019;:1–6.
: To review the current literature regarding optical coherence tomography angiography (OCT-A) applications in the anterior segment. : A literature search was performed for terms including OCT-Angiography, anterior segment, cornea, conjunctiva, iris, applications and use in ophthalmology. : Fifteen studies were identified, 14 in human subjects. Studies with OCT-A of the conjunctiva, episclera, cornea, and iris were identified, some with normal eyes imaged and others with various pathologies. Most of these studies imaged corneal neovascularization. Three studies described protocols used for image acquisition, one of which was referenced by two later papers. : OCT-A is a noninvasive technology with recent applications in the anterior segment. Several pilot studies have been performed on various anterior segment structures and disease states however standardization of image acquisition techniques is still needed. Future imaging could allow noninvasive and serial monitoring of pathology as well as recurrence after therapeutic intervention.