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Caroline J Zeiss

Publications and source records attributed to Caroline J Zeiss.

10 recordsLinked to original sources
PubMed2025

Impaired hematopoiesis and embryonic lethality at midgestation of mice lacking both lipid transfer proteins VPS13A and VPS13C.

VPS13 is the founding member of a family of proteins that mediate lipid transfer at intracellular membrane contact sites by a bridge-like mechanism. Mammalian genomes comprise 4 VPS13 genes encoding proteins with distinct localizations and function. The gene duplication resulting in VPS13A and VPS13C is the most recent in evolution and, accordingly, these two proteins are the most similar to each other. However, they have distinct subcellular localizations and their loss of function mutations in humans are compatible with life but result in two different age-dependent neurodegenerative diseases, chorea-acanthocytosis and Parkinson's disease, respectively. Thus, it remains unclear whether these two proteins have overlapping functions. Here, we show that while Vps13a KO and Vps13c KO mice are viable, embryonic development of Vps13a/Vps13c double knockout (DKO) mice is arrested at midgestation. Prior to death, DKO embryos were smaller than controls, were anemic and had a smaller liver, most likely reflecting defective embryonic erythropoiesis which at this developmental stage occurs primarily in this organ. Further analyses of erythroid precursor cells showed that their differentiation was impaired and that this defect was accompanied by activation of innate immunity as revealed by upregulation of interferon stimulated genes (ISGs). Additionally, the RIG-I and MDA5 components of dsRNA triggered innate immunity were found upregulated in the DKO fetal liver. Activation of innate immunity may result from loss of integrity of the membranes of intracellular organelles, such as mitochondria and autophagic lysosomes, or to impaired autophagy, due to the absence of these lipid transport proteins. The surprising and striking synthetic effect resulting for the combined loss of VPS13A and VPS13C suggests that despite of the different localization of these two proteins, the lipid fluxes that they mediate are partially redundant.

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PubMed2006

Safety of recombinant adeno-associated virus type 2-RPE65 vector delivered by ocular subretinal injection.

AAV2 delivery of the RPE65 gene to the retina of blind RPE65-deficient animals restores vision. This strategy is being considered for human trials in RPE65-associated Leber congenital amaurosis (LCA), but toxicity and dose efficacy have not been defined. We studied ocular delivery of AAV-2/2.RPE65 in RPE65-mutant dogs. There was no systemic toxicity. Ocular examinations showed mild or moderate inflammation that resolved over 3 months. Retinal histopathology indicated that traumatic lesions from the injection were common, but thinning within the injection region occurred only at the two highest vector doses. Biodistribution studies at 3 months postinjection showed no vector in optic nerve or visual centers in the brain and only isolated non-dose-related detection in other organs. We also performed biodistribution studies in normal rats at about 2 weeks and 2 months postinjection and vector was not widespread outside the injected eye. Dose-response results in RPE65-mutant dogs indicated that the highest 1.5-log unit range of vector doses proved efficacious. The efficacy and toxicity limits defined in this study lead to suggestions for the design of a subretinal AAV-2/2.RPE65 human trial of RPE65-associated LCA.

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PubMed2006

Safety in nonhuman primates of ocular AAV2-RPE65, a candidate treatment for blindness in Leber congenital amaurosis.

Leber congenital amaurosis (LCA) is a molecularly heterogeneous disease group that leads to blindness. LCA caused by RPE65 mutations has been studied in animal models and vision has been restored by subretinal delivery of AAV-RPE65 vector. Human ocular gene transfer trials are being considered. Our safety studies of subretinal AAV-2/2.RPE65 in RPE65-mutant dogs showed evidence of modest photoreceptor loss in the injection region in some animals at higher vector doses. We now test the hypothesis that there can be vectorrelated toxicity to the normal monkey, with its human-like retina. Good Laboratory Practice safety studies following single intraocular injections of AAV-2/2.RPE65 in normal cynomolgus monkeys were performed for 1-week and 3-month durations. Systemic toxicity was not identified. Ocular-specific studies included clinical examinations, electroretinography, and retinal histopathology. Signs of ocular inflammation postinjection had almost disappeared by 1 week. At 3 months, electroretinography in vector-injected eyes was no different than in vehicle-injected control eyes or compared with presurgical recordings. Healed sites of retinal perforation from subretinal injections were noted clinically and by histopathology. Foveal architecture in subretinally injected eyes, vector or vehicle, could be abnormal. Morphometry of central retina showed no photoreceptor layer thickness abnormalities occurring in a dose-dependent manner. Vector sequences were present in the injected retina, vitreous, and optic nerve at 1 week but not consistently in the brain. At 3 months, there were no vector sequences in optic nerve and brain. The results allow for consideration of an upper range for no observed adverse effect level in future human trials of subretinal AAV-2/2.RPE65. The potential value of foveal treatment for LCA and other retinal degenerations warrants further research into how to achieve gene transfer without retinal injury from surgical detachment of the retina.

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PubMed2005

CNTF induces dose-dependent alterations in retinal morphology in normal and rcd-1 canine retina.

Ciliary neurotrophic factor (CNTF) provides morphologic preservation of rods in several animal models of retinitis pigmentosa (RP). However, CNTF may alter photoreceptor morphology and rod photoreceptor differentiation in vitro, as well as affecting normal retinal electrophysiology. In addition, the capacity of CNTF to support other cell types affected secondarily in RP (cones and ganglion cells) is unclear. The purposes of this study were to examine the effects of CNTF upon a canine model of RP, the rod-cone degeneration (rcd-1) dog. Archival tissue from a previous study assessing the capacity of CNTF to rescue photoreceptors in rcd-1 dogs was used. One eye was treated for 7 weeks before being explanted. The contralateral eye was untreated. A total of 23 rcd-1 dogs and seven control dogs (four untreated and three CNTF-treated) were used. Morphometric data describing outer and inner nuclear layer thickness, inner retinal thickness, cones and ganglion cells were collected at nine evenly spaced points along each retina and analysed using a mixed effects model. Immunohistochemistry was performed on a subset of 11 dogs for expression of rhodopsin, human cone arrestin (hCAR) and recoverin. CNTF protected the outer nuclear layer and increased inner retinal thickness in a dose-dependent manner (both were maximal at CNTF doses of 1-6 ng day-1). Significant cone loss or reduction of inner nuclear layer width in rcd-1 did not occur in this model, therefore we were unable to assess the protective effect of CNTF upon these parameters. CNTF did not afford significant ganglion cell protection. CNTF induced morphologic changes in rods and ganglion cells, as well as reducing expression of hCAR and rhodopsin, but not recoverin. The dose of CNTF which provided optimal outer nuclear layer protection also resulted in several other effects, including altered ganglion cell morphology, increased thickness of the entire retina, and reduced expression of some phototransduction proteins. These changes were more marked in rcd-1 retinas than in wild-type retinas. This implies that the consequences of CNTF treatment may be substantially influenced by the cellular context into which it is introduced.

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PubMed2005

Successful cyclosporine treatment for atopic dermatitis in a rhesus macaque (Macaca mulatta).

A juvenile (1 year old ) female rhesus macaque (Macaca mulatta) developed a chronic active skin condition characterized by pruritus, erythema, alopecia, scaling, exfoliation, and lichenification. Lesions were limited to the ventrum, specifically rostral mandible and neck, axilla and inguinal regions, distal extremities, and interdigital regions. Differential diagnoses included infection, dietary deficiency, metabolic abnormality, endocrinopathy, and immunological injury. Diagnostic tests included complete hemogram, serum chemistry, skin scrapes for ectoparasite detection, hair plucks for dermatophyte culture, and a serum-based hypersensitivity panel. All results were within normal limits. Dermal biopsies revealed lesions consistent with active allergic dermatitis, and a diagnosis of atopic dermatitis was made. Oral cyclosporine (5 mg/kg daily) rapidly eliminated clinical evidence of dermatitis. Histologically, lesions resolved after 12 months of treatment. Atopic dermatitis is an inflammatory skin condition for which there are neither pathognomonic clinical or diagnostic features nor a single successful therapy. Basic criteria such as pruritus, lichenification, a chronic course, and history of allergies strongly support the diagnosis. One successful therapeutic agent is a macrolide calcineurin inhibitor, cyclosporine. It represents a safer class of immunomodulatory drugs than corticosteroids and provides targeted alteration of lymphocyte function. To our knowledge this case represents the first reported successful treatment of atopic dermatitis in a nonhuman primate utilizing cyclosporine.

Administration, Oral↗
PubMed2004

Proliferation of microglia, but not photoreceptors, in the outer nuclear layer of the rd-1 mouse.

PURPOSE: To establish whether photoreceptor apoptosis in the rd-1 mouse is accompanied by cell cycle progression. Studies of cell cycle proteins in other models of neuronal death provide consistent evidence that a repertoire of proliferative markers accompanies apoptosis. METHODS: The spatiotemporal progression of photoreceptor loss in rd-1 and control mice at postnatal days (PN)8, -10, -12, -15, and -18 was correlated with markers of G(1)- and S-phase progression. Photoreceptor death was detected by using morphology and terminal dUTP transferase nick end labeling (TUNEL). Cell-cycle-associated markers consisted of bromodeoxyuridine (BrdU) uptake, and immunolabeling for proliferating cell nuclear antigen (PCNA), Ki-67, and cyclin-dependent kinases-2 and -4. The identity of proliferating cells in the outer nuclear layer was established by double immunolabeling with PCNA and either F4/80 or recoverin. RESULTS: A population of proliferating cells in the outer nuclear layer accompanies photoreceptor death along a central to peripheral gradient in rd-1 retinas. Double immunolabeling for PCNA and F4/80 readily identified these as microglial cells originating from the inner retina. Cell cycle progression in photoreceptors could not be demonstrated. CONCLUSIONS: These findings confirm that in rd-1, a preexisting condition for cell cycle progression does not exist as it does in other neurodegenerative conditions. Therefore, in this model, evidence of photoreceptor cell cycle progression in retinas exposed to neurotrophic factors is likely to result from the therapy itself. In addition, the results confirmed that proliferating microglial cells are intimately associated with the degenerative process in rd-1.

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PubMed2004

Caspase-3 in postnatal retinal development and degeneration.

PURPOSE: The primary purpose of this study was to evaluate the impact of caspase-3 ablation on photoreceptor degeneration in the rd-1 mouse. Concurrently, the role of caspase-3 in postnatal retinal development was evaluated. Caspase-3 is an important effector caspase that mediates many of the terminal proteolytic events of apoptosis. Its activation has been demonstrated in rodent models of photoreceptor degeneration and its ablation results in exencephaly and neonatal death. METHODS: Retinal morphometry was performed at the light microscopic level in caspase-3 mutant mice from PN0 through PN23, and in rd-1/caspase-3 double mutant mice at PN14, -16, and -18. This was supplemented by terminal dUTP transferase nick end labeling (TUNEL) and immunohistochemical staining for activated caspase-3, rhodopsin, factor VII-related antigen and proliferating cell nuclear antigen (PCNA). RESULTS: Caspase-3-deficient animals display marginal microphthalmia, peripapillary retinal dysplasia, delayed regression of vitreal vasculature, and retarded apoptotic kinetics of the inner nuclear layer. Ablation of caspase-3 provided transient photoreceptor protection in rd-1, but TUNEL-positive rod death proceeded, despite the absence of caspase-3 activation. CONCLUSIONS: In vivo, caspase-3 is not critical for rod photoreceptor development, nor does it play a significant role in mediating pathologic rod death. Peripapillary dysplastic lesions suggest that there is delayed fusion of the optic fissure, and inner nuclear layer abnormalities indicate a cell-specific dependency on the mitochondria-caspase axis during development. The temporal nature of apoptotic retardation in the absence of caspase-3 implies the presence of caspase-independent mechanisms of developmental and pathologic cell death.

Animals↗
PubMed2003

Pathogenesis of mouse hepatitis virus infection in gamma interferon-deficient mice is modulated by co-infection with Helicobacter hepaticus.

Gamma interferon-deficient (IFN-gamma KO) mice developed a wasting syndrome and were found to be co-infected with Helicobacter sp., and a new isolate of mouse hepatitis virus (MHV) designated MHV-G. The disease was characterized by pleuritis, peritonitis, hepatitis, pneumonia, and meningitis. Initial experiments used a cecal homogenate inoculum from the clinical cases that contained H. hepaticus and MHV-G to reproduce the development of peritonitis and pleuritis in IFN-gamma KO mice. In contrast, immunocompetent mice given the same inoculum developed an acute, self-limiting infection and remained clinically normal. This result confirmed the importance of IFN-gamma in preventing chronic infection and limiting viral dissemination. To understand the role of both agents in the development of peritonitis and pleuritis, IFN-gamma KO mice were infected with either agent or were co-infected with H. hepaticus and MHV-G. Infection with MHV-G induced a multisystemic infection similar to that described in the original cases, with multifocal hepatic necrosis, acute necrotizing and inflammatory lesions of the gastrointestinal tract, and acute peritonitis and pleuritis with adhesions on the serosal surfaces of the viscera. However, mice given H. hepaticus alone had minimal pathologic changes even though the organism was consistently detected in the cecum or feces. Although co-infection with H. hepaticus and MHV-G induced lesions similar to those associated with MHV-G alone, the pathogenesis of the MHV infection was modified. Helicobacter hepaticus appeared to reduce the severity of MHV-induced lesions during the acute phase of infection, and exacerbated hepatitis and meningitis at the later time point. We conclude that infection of IFN-gamma KO mice with MHV-G results in multisystemic infection with peritonitis, pleuritis, and adhesions due to the aberrant immune response in these mice. In addition, co-infection of these mice with H. hepaticus results in alterations in the pathogenesis of MHV-G infection.

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PubMedDate not supplied

A morphologic study of intravitreal membranes associated with intraocular hemorrhage in the dog.

Abstract We aimed to characterize intravitreal membranes in dogs and determine, if possible, associated predisposing conditions. Five globes in which intravitreal membranes were identified were evaluated. These originated from four Labrador Retrievers or Labrador-cross dogs and a Springer Spaniel. The ages of the dogs ranged from 4 to 11 years. Standard histology and immunohistochemical procedures for factor VIII-related antigen, smooth muscle actin (SMA), vimentin and glial fibrillary acidic protein (GFAP) were performed. Intravitreal membranes varied from loosely to highly organized. The extent of organization corresponded with increasing immunoreactivity for vimentin and GFAP, indicating their predominantly glial origin. They were never immunopositive for smooth muscle actin, nor were they vascularized. In all cases, they were associated with intravitreal hemorrhage. Additional common findings included epiretinal membranes, retinal neovascularization, preiridal fibrovascular membranes and glaucoma. Intravitreal membranes may be a sequelae of intravitreal hemorrhage. This in turn, may arise from new vessels associated with epiretinal or preiridial membranes, or hemorrhage associated with optic disc cupping or retinal neovascularization. All of these phenomena may accompany glaucoma.

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