Publications

2018

O’Connell A, Zhou F, Shah M, Murphy Q, Rickner H, Kelsen J, Boyle J, Doyle J, Gangwani B, Thiagarajah J, Kamin D, Goldsmith J, Richmond C, Breault D, Agrawal P. Neonatal-Onset Chronic Diarrhea Caused by Homozygous Nonsense WNT2B Mutations. Am J Hum Genet. 2018;103(1):131–137.
Homozygous nonsense mutations in WNT2B were identified in three individuals from two unrelated families with severe, neonatal-onset osmotic diarrhea after whole-exome sequencing was performed on trios from the two families. Intestinal biopsy samples from affected individuals were used for histology and immunofluorescence and to generate enteroids ex vivo. Histopathologic evaluation demonstrated chronic inflammatory changes in the stomach, duodenum, and colon. Immunofluorescence demonstrated diminished staining for OLFM4, a marker for intestinal stem cells (ISCs). The enteroids generated from WNT2B-deficient intestinal epithelium could not be expanded and did not survive passage. Addition of CHIR-99021 (a GSK3A and GSK3B inhibitor and activator of canonical WNT/β-CATENIN signaling) could not rescue WNT2B-deficient enteroids. Addition of supplemental recombinant murine WNT2B was able to perpetuate small enteroids for multiple passages but failed to expand their number. Enteroids showed a 10-fold increase in the expression of LEF1 mRNA and a 100-fold reduction in TLR4 expression, compared with controls by quantitative RT-PCR, indicating alterations in canonical WNT and microbial pattern-recognition signaling. In summary, individuals with homozygous nonsense mutations in WNT2B demonstrate severe intestinal dysregulation associated with decreased ISC number and function, likely explaining their diarrheal phenotype. WNT2B deficiency should be considered for individuals with neonatal-onset diarrhea.
Oellers P, Wolkow N, Jakobiec F, Kim I. Hemorrhagic choroidal melanoma. Am J Ophthalmol Case Rep. 2018;10:105–107.
Purpose: To demonstrate the clinical pathologic correlation in a hemorrhagic choroidal melanoma. Observations: A 52 year old patient presented with a large choroidal mass associated with vitreous and retinal hemorrhage. The eye was enucleated and histopathology demonstrated epithelioid-type MART1 positive tumor cells consistent with choroidal melanoma. The tumor had broken through Bruch's membrane, which led to localized vascular compression with bleeding into the subretinal space, retina and vitreous. Conclusions and importance: Choroidal melanoma rarely presents with hemorrhage. Tumor rupture through Bruch's membrane may result in a tourniquet effect on the tumor vasculature leading to massive hemorrhage, as in this case. A high level of clinical suspicion is required to make the diagnosis.
Okunuki Y, Mukai R, Pearsall E, Klokman G, Husain D, Park DH, Korobkina E, Weiner H, Butovsky O, Ksander B, Miller J, Connor K. Microglia inhibit photoreceptor cell death and regulate immune cell infiltration in response to retinal detachment. Proc Natl Acad Sci U S A. 2018;115(27):E6264-E6273.
Retinal detachment (RD) is a sight-threatening complication common in many highly prevalent retinal disorders. RD rapidly leads to photoreceptor cell death beginning within 12 h following detachment. In patients with sustained RD, progressive visual decline due to photoreceptor cell death is common, leading to significant and permanent loss of vision. Microglia are the resident immune cells of the central nervous system, including the retina, and function in the homeostatic maintenance of the neuro-retinal microenvironment. It is known that microglia become activated and change their morphology in retinal diseases. However, the function of activated microglia in RD is incompletely understood, in part because of the lack of microglia-specific markers. Here, using the newly identified microglia marker P2ry12 and microglial depletion strategies, we demonstrate that retinal microglia are rapidly activated in response to RD and migrate into the injured area within 24 h post-RD, where they closely associate with infiltrating macrophages, a population distinct from microglia. Once in the injured photoreceptor layer, activated microglia can be observed to contain autofluorescence within their cell bodies, suggesting they function to phagocytose injured or dying photoreceptors. Depletion of retinal microglia results in increased disease severity and inhibition of macrophage infiltration, suggesting that microglia are involved in regulating neuroinflammation in the retina. Our work identifies that microglia mediate photoreceptor survival in RD and suggests that this effect may be due to microglial regulation of immune cells and photoreceptor phagocytosis.
Ravindran K, Schmalz P, Torun N, Ronthal M, Chang YM, Thomas A. Angiographic Findings in the Tolosa-Hunt Syndrome and Resolution after Corticosteroid Treatment. Neuroophthalmology. 2018;42(3):159–163.
The Tolosa-Hunt syndrome is a rare clinical condition characterized by painful opthalmoparesis associated with idiopathic granulomatous inflammation of the orbital apex and cavernous sinus. Historically, this condition was thought to result from arteritic changes in the internal carotid artery and cavernous sinus. Modern digital angiographic techniques were unavailable when THS was initially described, and few reports exist on its high-resolution angiographic findings. Painful ophthalmoparesis, especially of the oculomotor nerve, warrants vascular imaging because of the concern for an underlying aneurysm. Here, we describe angiographic findings of THS which may be useful for clinicians when encountering patients presenting with painful ophthalmoplegia.
Shi C, Yuan X, Chang K, Cho KS, Xie XS, Chen DF, Luo G. Optimization of Optomotor Response-based Visual Function Assessment in Mice. Sci Rep. 2018;8(1):9708.
Optomotor response/reflex (OMR) assays are emerging as a powerful and versatile tool for phenotypic study and new drug discovery for eye and brain disorders. Yet efficient OMR assessment for visual performance in mice remains a challenge. Existing OMR testing devices for mice require a lengthy procedure and may be subject to bias due to use of artificial criteria. We developed an optimized staircase protocol that utilizes mouse head pausing behavior as a novel indicator for the absence of OMR, to allow rapid and unambiguous vision assessment. It provided a highly sensitive and reliable method that can be easily implemented into automated or manual OMR systems to allow quick and unbiased assessment for visual acuity and contrast sensitivity in mice. The sensitivity and quantitative capacity of the protocol were validated using wild type mice and an inherited mouse model of retinal degeneration - mice carrying rhodopsin deficiency and exhibiting progressive loss of photoreceptors. Our OMR system with this protocol was capable of detecting progressive visual function decline that was closely correlated with the loss of photoreceptors in rhodopsin deficient mice. It provides significant advances over the existing methods in the currently available OMR devices in terms of sensitivity, accuracy and efficiency.
Shoji M, Saeed H, Habib L, Freitag S. Epibulbar Mass With Upper Eyelid Cleft and Focal Scalp Alopecia in a Neonate: A New Case of Oculoectodermal Syndrome. Ophthalmic Plast Reconstr Surg. 2018;34(4):e133-e136.
A female neonate presented with a pedunculated left lateral epibulbar mass protruding through the eyelids that originated from the temporal cornea and superolateral bulbar and palpebral conjunctiva. She had a cleft in the ipsilateral central upper eyelid with horizontal kink of the tarsus lateral to the cleft and focal patches of alopecia on the scalp. Histopathology of the epibulbar mass revealed conjunctival epithelium with underlying connective tissue, cartilage, bone, adipose, and lacrimal gland consistent with epibulbar dermoid. Genetic testing of the surgical specimen was positive for a KRAS mutation at position 146. MRI showed subarachnoid asymmetry around the left temporal lobe and a C1-C2 enhancing lesion. These clinical and molecular findings suggest that this patient has a new clinical variant of oculoectodermal syndrome, a rare disorder associated with somatic KRAS gene mutations and characterized clinically by epibulbar dermoids, alopecia, aplasia cutis, brain anomalies, umbilical hernias, and congenital heart defects.
Singh AK, Phillips F, Merabet L, Sinha P. Why Does the Cortex Reorganize after Sensory Loss?. Trends Cogn Sci. 2018;22(7):569–582.
A growing body of evidence demonstrates that the brain can reorganize dramatically following sensory loss. Although the existence of such neuroplastic crossmodal changes is not in doubt, the functional significance of these changes remains unclear. The dominant belief is that reorganization is compensatory. However, results thus far do not unequivocally indicate that sensory deprivation results in markedly enhanced abilities in other senses. Here, we consider alternative reasons besides sensory compensation that might drive the brain to reorganize after sensory loss. One such possibility is that the cortex reorganizes not to confer functional benefits, but to avoid undesirable physiological consequences of sensory deafferentation. Empirical assessment of the validity of this and other possibilities defines a rich program for future research.
Sood A, O’Keefe G, Bui D, Jain N. Vogt-Koyanagi-Harada Disease Associated with Hepatitis B Vaccination. Ocul Immunol Inflamm. 2018;:1–4.
PURPOSE: To report a case of Vogt-Koyanagi-Harada (VKH) disease associated with hepatitis B vaccination. METHODS: Case report. RESULTS: A 43-year-old Caucasian male presented with a three-week history of blurry vision, pain, photophobia, and redness in both eyes. Three days prior to the onset of symptoms, he had received the hepatitis B virus vaccine. Clinical evaluation revealed multifocal placoid lesions in the posterior pole, choroidal thickening, and serous macular detachment. Targeted laboratory investigations were negative for infectious or autoimmune markers. After treatment with oral corticosteroids, the patient had resolution of symptoms with near-total recovery of visual function. The patient later reported systemic findings of hearing loss, tinnitus, and integumentary changes. A diagnosis of VKH disease was made and inflammation was managed with oral corticosteroids followed by methotrexate for long-term disease control. CONCLUSIONS: VKH disease is an inflammatory condition primarily affecting the choroid, retinal pigment epithelium, and outer retina. The underlying etiology is unclear, but it can be associated with a viral prodrome suggesting an infectious trigger in a genetically susceptible individual. Our case suggests that hepatitis B vaccination may trigger a similar inflammatory response.
Stern J, Tian Y, Funderburgh J, Pellegrini G, Zhang K, Goldberg J, Ali R, Young M, Xie Y, Temple S. Regenerating Eye Tissues to Preserve and Restore Vision. Cell Stem Cell. 2018;22(6):834–849.
Ocular regenerative therapies are on track to revolutionize treatment of numerous blinding disorders, including corneal disease, cataract, glaucoma, retinitis pigmentosa, and age-related macular degeneration. A variety of transplantable products, delivered as cell suspensions or as preformed 3D structures combining cells and natural or artificial substrates, are in the pipeline. Here we review the status of clinical and preclinical studies for stem cell-based repair, covering key eye tissues from front to back, from cornea to retina, and including bioengineering approaches that advance cell product manufacturing. While recognizing the challenges, we look forward to a deep portfolio of sight-restoring, stem cell-based medicine. VIDEO ABSTRACT.