scholarly journals Notch inhibition promotes regeneration and immunosuppression supports cone survival in a zebrafish model of inherited retinal dystrophy

2021 ◽  
Author(s):  
Joseph Fogerty ◽  
Ping Song ◽  
Patrick Boyd ◽  
Sarah Grabinski ◽  
Thanh Hoang ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Vision Loss ◽  
Retinal Dystrophy ◽  
Photoreceptor Degeneration ◽  
Zebrafish Model ◽  
Reactive Microglia ◽  
Multipotent Progenitors ◽  
Inherited Retinal Dystrophy ◽  
Ability To Regenerate ◽  
Mature Neurons

Photoreceptor degeneration leads to irreversible vision loss in humans with retinal dystrophies such as Retinitis Pigmentosa. Whereas photoreceptor loss is permanent in mammals, zebrafish possesses the ability to regenerate retinal neurons and restore visual function. Following acute damage, Muller glia (MG) re-enter the cell cycle and produce multipotent progenitors whose progeny differentiate into mature neurons. Both MG reprogramming and proliferation of retinal progenitor cells require reactive microglia and associated inflammatory signaling. Paradoxically, MG in zebrafish models of photoreceptor degeneration fail to re-enter the cell cycle and regenerate lost cells. Here, we used the zebrafish cep290 mutant to demonstrate that progressive cone degeneration generates an immune response but does not stimulate MG proliferation. Acute light damage triggered photoreceptor regeneration in cep290 mutants but cones were only restored to pre-lesion densities. Using irf8 mutant zebrafish, we found that the chronic absence of microglia reduced inflammation and rescued cone degeneration in cep290 mutants. Finally, single-cell RNA-sequencing revealed sustained expression of notch3 in MG of cep290 mutants and inhibition of Notch signaling induced MG to re-enter the cell cycle. Our findings provide new insights on the requirements for MG to proliferate and the potential for immunosuppression to prolong photoreceptor survival.

A mutation in CRX causing pigmented paravenous retinochoroidal atrophy

2020 ◽  
pp. 112067212095759
Author(s):  
Jin Kyun Oh ◽  
Yan Nuzbrokh ◽  
Winston Lee ◽  
Jose Ronaldo Lima de Carvalho ◽  
Nan Kai Wong ◽  
...  
Keyword(s):  
Vision Loss ◽  
Retinal Dystrophy ◽  
Cone Dystrophy ◽  
Full Field ◽  
Inherited Retinal Dystrophy ◽  
History Of ◽  
Pigmented Paravenous Retinochoroidal Atrophy ◽  
Retinal Thinning ◽  
Bull's Eye ◽  
Sd Oct

Introduction: Mutations in the cone-rod homeobox ( CRX) gene, a known cause of inherited retinal dystrophy, are characterized by extensive phenotypic heterogeneity. We describe a novel presentation of rod-cone dystrophy (RCD) phenocopying pigmented paravenous retinochoroidal atrophy associated with a mutation in CRX. Case description: A 53-year-old man and his 48-year-old brother presented with a history of progressive vision loss and nyctalopia. Fundus examination revealed a bull’s eye lesion with chorioretinal atrophy and intraretinal pigment migration, while spectral-domain optical coherence tomography (SD-OCT) demonstrated retinal thinning with outer retinal atrophy. On short-wavelength autofluorescence (SW-AF) imaging, an atypical paravenous pattern of atrophy with a surrounding hyperautofluorescent border was observed. Full-field electroretinogram (ffERG) revealed a rod-cone pattern of dysfunction. A heterozygous pathogenic variant, c.119G>A:p.(Arg40Gln), in the CRX gene was identified in both brothers and segregated in their family. Conclusion: This case report broadens the currently known phenotypic presentations of CRX-associated retinopathy and suggests that mutations in CRX may be associated with pigmented paravenous retinochoroidal atrophy.

Photoreceptor degeneration in inherited retinal dystrophy delayed by basic fibroblast growth factor

Nature ◽  
1990 ◽  
Vol 347 (6288) ◽  
pp. 83-86 ◽  
Author(s):  
Ella G. Faktorovich ◽  
Roy H. Steinberg ◽  
Douglas Yasumura ◽  
Michael T. Matthes ◽  
Matthew M. LaVail
Keyword(s):  
Growth Factor ◽  
Fibroblast Growth Factor ◽  
Basic Fibroblast Growth Factor ◽  
Retinal Dystrophy ◽  
Fibroblast Growth ◽  
Photoreceptor Degeneration ◽  
Inherited Retinal Dystrophy

scholarly journals Allele-Specific Knockout by CRISPR/Cas to Treat Autosomal Dominant Retinitis Pigmentosa Caused by the G56R Mutation in NR2E3

2021 ◽  
Vol 22 (5) ◽  
pp. 2607
Author(s):  
Michalitsa Diakatou ◽  
Gregor Dubois ◽  
Nejla Erkilic ◽  
Carla Sanjurjo-Soriano ◽  
Isabelle Meunier ◽  
...  
Keyword(s):  
Retinitis Pigmentosa ◽  
Autosomal Dominant ◽  
Vision Loss ◽  
Retinal Dystrophy ◽  
Common Mutation ◽  
Wild Type ◽  
Inherited Retinal Dystrophy ◽  
Allele Specific ◽  
Induced Pluripotent ◽  
Overexpression System

Retinitis pigmentosa (RP) is an inherited retinal dystrophy that causes progressive vision loss. The G56R mutation in NR2E3 is the second most common mutation causing autosomal dominant (ad) RP, a transcription factor that is essential for photoreceptor development and maintenance. The G56R variant is exclusively responsible for all cases of NR2E3-associated adRP. Currently, there is no treatment for NR2E3-related or, other, adRP, but genome editing holds promise. A pertinent approach would be to specifically knockout the dominant mutant allele, so that the wild type allele can perform unhindered. In this study, we developed a CRISPR/Cas strategy to specifically knockout the mutant G56R allele of NR2E3 and performed a proof-of-concept study in induced pluripotent stem cells (iPSCs) of an adRP patient. We demonstrate allele-specific knockout of the mutant G56R allele in the absence of off-target events. Furthermore, we validated this knockout strategy in an exogenous overexpression system. Accordingly, the mutant G56R-CRISPR protein was truncated and mis-localized to the cytosol in contrast to the (peri)nuclear localizations of wild type or G56R NR2E3 proteins. Finally, we show, for the first time, that G56R iPSCs, as well as G56R-CRISPR iPSCs, can differentiate into NR2E3-expressing retinal organoids. Overall, we demonstrate that G56R allele-specific knockout by CRISPR/Cas could be a clinically relevant approach to treat NR2E3-associated adRP.

Na-K-activated adenosinetriphosphatase in retinae of rats with and without inherited retinal dystrophy

1970 ◽  
Vol 10 (5) ◽  
pp. 435-438 ◽  
Author(s):  
F.J.M. Daemen ◽  
J.J.H.H.M. de Pont ◽  
F. Lion ◽  
S.L. Bonting
Keyword(s):  
Retinal Dystrophy ◽  
Inherited Retinal Dystrophy

Abstract 2357: Src Kinase Inhibition Blocks Thrombin-induced Brain Injuries without Cognitive Side Effects

Stroke ◽  
2012 ◽  
Vol 43 (suppl_1) ◽  
Author(s):  
Da-Zhi Liu ◽  
Bradley P Ander ◽  
Ali Izadi ◽  
Ken Van ◽  
Xinhua Zhan ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cognitive Deficits ◽  
Neuronal Cell ◽  
Thrombin Injection ◽  
Cell Cycle Reentry ◽  
Cell Cycle Inhibition ◽  
Mature Neurons ◽  
Cognitive Side Effects

Intracerebral hemorrhage (ICH) activates thrombin, a potent mitogen. Thrombin triggers mitosis by modulating several intracellular mitogenic molecules including Src family kinases. These molecules regulate mitogen-activated protein kinases (MAPKs) and cell cycle proteins such as cyclin-dependent kinases (Cdks); and play critical roles in mitogenic signaling pathways and cell cycle progression. Since aberrant cell cycle reentry results in death of mature neurons, cell cycle inhibition appears to be a candidate strategy for the treatment of neurological diseases including ICH. However, this can also block cell cycle (proliferation) of neural progenitor cells (NPCs) and thus impair brain neurogenesis leading to cognitive deficits. We hypothesized that inhibition of cell cycle by blocking mitogenic signaling molecules (i.e., Src family kinase members) blocks cell cycle reentry of mature neurons without injuring NPCs, which will avoid cognitive side effects during cell cycle inhibition treatment for ICH. Our data shows: (1) Thrombin 30U/ml results in apoptosis of mature neurons via neuronal cell cycle reentry in vitro ; (2) PP2 (Src family kinase inhibitor) 0.3 µM attenuates the thrombin-induced neuronal apoptosis via blocking neuronal cell cycle reentry, but does not affect the viability of NPCs at the same doses in vitro ; (3) Intracerebral ventricular thrombin injection (20U, i.c.v.) results in neuron loss in hippocampus and cognitive deficits 5 weeks after thrombin injection in vivo ; (4) PP2 (1mg/kg, i.p.), given immediately after thrombin injection (i.c.v.), blocks the thrombin-induced neuron loss in hippocampus and cognitive deficits, whereas PP2 on its own at the same doses does not affect normal cognition in vivo . These suggest that Src kinase inhibition prevents hippocampal neuron death via blocking neuronal cell cycle reentry after ICH, but does not affect survival of NPCs.

scholarly journals Drusen in patient-derived hiPSC-RPE models of macular dystrophies

2017 ◽  
Vol 114 (39) ◽  
pp. E8214-E8223 ◽  
Author(s):  
Chad A. Galloway ◽  
Sonal Dalvi ◽  
Sandy S. C. Hung ◽  
Leslie A. MacDonald ◽  
Lisa R. Latchney ◽  
...  
Keyword(s):  
Vision Loss ◽  
Retinal Pigment ◽  
Retinal Dystrophy ◽  
Age Related Macular Degeneration ◽  
In Vivo Studies ◽  
Specific Cell ◽  
Rpe Cells ◽  
Age Related ◽  
Pathway Gene ◽  
Human Pathology

Age-related macular degeneration (AMD) and related macular dystrophies (MDs) are a major cause of vision loss. However, the mechanisms underlying their progression remain ill-defined. This is partly due to the lack of disease models recapitulating the human pathology. Furthermore, in vivo studies have yielded limited understanding of the role of specific cell types in the eye vs. systemic influences (e.g., serum) on the disease pathology. Here, we use human induced pluripotent stem cell-retinal pigment epithelium (hiPSC-RPE) derived from patients with three dominant MDs, Sorsby’s fundus dystrophy (SFD), Doyne honeycomb retinal dystrophy/malattia Leventinese (DHRD), and autosomal dominant radial drusen (ADRD), and demonstrate that dysfunction of RPE cells alone is sufficient for the initiation of sub-RPE lipoproteinaceous deposit (drusen) formation and extracellular matrix (ECM) alteration in these diseases. Consistent with clinical studies, sub-RPE basal deposits were present beneath both control (unaffected) and patient hiPSC-RPE cells. Importantly basal deposits in patient hiPSC-RPE cultures were more abundant and displayed a lipid- and protein-rich “drusen-like” composition. Furthermore, increased accumulation of COL4 was observed in ECM isolated from control vs. patient hiPSC-RPE cultures. Interestingly, RPE-specific up-regulation in the expression of several complement genes was also seen in patient hiPSC-RPE cultures of all three MDs (SFD, DHRD, and ADRD). Finally, although serum exposure was not necessary for drusen formation, COL4 accumulation in ECM, and complement pathway gene alteration, it impacted the composition of drusen-like deposits in patient hiPSC-RPE cultures. Together, the drusen model(s) of MDs described here provide fundamental insights into the unique biology of maculopathies affecting the RPE–ECM interface.

scholarly journals Innate and Autoimmunity in the Pathogenesis of Inherited Retinal Dystrophy

Cells ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 630 ◽  
Author(s):  
T. J. Hollingsworth ◽  
Alecia K. Gross
Keyword(s):  
Disease Progression ◽  
Age Of Onset ◽  
Retinal Dystrophy ◽  
Inherited Retinal Dystrophies ◽  
Retinal Dystrophies ◽  
Major Player ◽  
Inherited Retinal Dystrophy ◽  
Rate Of Progression ◽  
Immunohistochemical Methods ◽  
Onset Rate

Inherited retinal dystrophies (RDs) are heterogenous in many aspects including genes involved, age of onset, rate of progression, and treatments. While RDs are caused by a plethora of different mutations, all result in the same outcome of blindness. While treatments, both gene therapy-based and drug-based, have been developed to slow or halt disease progression and prevent further blindness, only a small handful of the forms of RDs have treatments available, which are primarily for recessively inherited forms. Using immunohistochemical methods coupled with electroretinography, optical coherence tomography, and fluorescein angiography, we show that in rhodopsin mutant mice, the involvement of both the innate and the autoimmune systems could be a strong contributing factor in disease progression and pathogenesis. Herein, we show that monocytic phagocytosis and inflammatory cytokine release along with protein citrullination, a major player in forms of autoimmunity, work to enhance the progression of RD associated with a rhodopsin mutation.

Sign in / Sign up

Export Citation Format

Share Document