- Open Access
Marked central nervous system pathology in CD59 knockout rats following passive transfer of Neuromyelitis optica immunoglobulin G
© The Author(s). 2017
- Received: 29 December 2016
- Accepted: 3 February 2017
- Published: 17 February 2017
Neuromyelitis optica spectrum disorders (herein called NMO) is an inflammatory demyelinating disease of the central nervous system in which pathogenesis involves complement-dependent cytotoxicity (CDC) produced by immunoglobulin G autoantibodies targeting aquaporin-4 (AQP4-IgG) on astrocytes. We reported evidence previously, using CD59−/− mice, that the membrane-associated complement inhibitor CD59 modulates CDC in NMO (Zhang and Verkman, J. Autoimmun. 53:67–77, 2014). Motivated by the observation that rats, unlike mice, have human-like complement activity, here we generated CD59−/− rats to investigate the role of CD59 in NMO and to create NMO pathology by passive transfer of AQP4-IgG under conditions in which minimal pathology is produced in normal rats. CD59−/− rats generated by CRISPR/Cas9 technology showed no overt phenotype at baseline except for mild hemolysis. CDC assays in astrocyte cultures and cerebellar slices from CD59−/− rats showed much greater sensitivity to AQP4-IgG and complement than those from CD59+/+ rats. Intracerebral administration of AQP4-IgG in CD59−/− rats produced marked NMO pathology, with astrocytopathy, inflammation, deposition of activated complement, and demyelination, whereas identically treated CD59+/+ rats showed minimal pathology. A single, intracisternal injection of AQP4-IgG in CD59−/− rats produced hindlimb paralysis by 3 days, with inflammation and deposition of activated complement in spinal cord, optic nerves and brain periventricular and surface matter, with most marked astrocyte injury in cervical spinal cord. These results implicate an important role of CD59 in modulating NMO pathology in rats and demonstrate amplification of AQP4-IgG-induced NMO disease with CD59 knockout.
- Complement inhibitor
- Complement-dependent cytotoxicity
- Transgenic rat
Neuromyelitis optica spectrum disorders (herein called NMO) is an inflammatory demyelinating disease of the central nervous system with characteristic pathological features in spinal cord and optic nerves, and to a lesser extent in brain. Most NMO patients are seropositive for immunoglobulin G autoantibodies against astrocyte water channel aquaporin-4 (AQP4), called AQP4-IgG (or NMO-IgG) [13, 14]. The major pathological features in seropositive NMO include astrocyte damage, inflammation with prominent granulocyte and macrophage infiltration, vasculocentric deposition of activated complement, and demyelination, which can produce marked neurological deficits [10, 19, 26]. There is abundant evidence that pathogenesis in AQP4-IgG seropositive NMO patients involves AQP4-IgG binding to AQP4 on astrocytes and activation of the classical complement system, which causes complement-dependent cytotoxicity (CDC) leading to inflammation, blood–brain barrier disruption and demyelination [8, 13, 19]. Antibody-dependent cell-mediated cytotoxicity (ADCC)  and sensitized T cells [22, 35, 36] may also play a role in NMO pathogenesis.
Several lines of evidence implicate a major role for complement activation in NMO, including human pathology showing deposition of activated complement [16, 18, 26], rodent models showing complement-dependent NMO pathology following passive transfer of AQP4-IgG [1, 28, 37], and an open-label clinical trial of the C5 convertase inhibitor eculizumab showing efficacy in NMO . We previously reported that complement inhibitor protein CD59, a phosphoinositol-linked membrane glycoprotein expressed on astrocytes that inhibits formation of the terminal membrane attack complex, may be an important regulator of complement action in NMO . CD59−/− mice are highly sensitive to administration of AQP4-IgG and human complement, with longitudinally extensive NMO spinal cord pathology produced by coinjection of AQP4-IgG and complement into the lumbosacral cerebrospinal space. However, a major limitation of mice as models of NMO is the near-zero activity of their classical complement pathway, in part because of complement inhibitory factor(s) present in mouse serum . The ineffective classical complement pathway in mice precludes the development of clinically relevant NMO models, such as robust passive-transfer models of NMO optic neuritis and transverse myelitis, as well as testing of NMO therapeutics such as complement inhibitors.
To overcome these limitations and to further investigate the role of CD59 in NMO pathogenesis, here we generated CD59−/− rats and determined their sensitivity to passive transfer of AQP-IgG. We previously showed that passive transfer of AQP4-IgG to rats, without added complement, by a single intracerebral injection produced NMO pathology in brain at the site of injection . We tested here the prediction that marked NMO pathology might be produced in the central nervous system by passive transfer of AQP4-IgG to CD59−/− rats, without added complement, under conditions where minimal pathology is produced in CD59+/+ rats.
Purified recombinant AQP4-IgG (rAb-53) was provided by Dr. Jeffrey Bennett (Univ. Colorado, Denver). Human complement was purchased from Innovative Research (Novi, MI) and human control IgG from Pierce Biotechnology (Rockford, IL). Unless otherwise specified chemicals were purchased from Sigma-Aldrich (St. Louis, MO).
Astrocyte cell culture
Primary astrocyte cultures were generated from brain cortex of neonatal CD59+/+ and CD59−/− rats at day 7 post birth, as described  with modification. Briefly, the cerebral hemispheres were isolated and cortical tissue was minced and incubated for 15 min at 37 °C in 0.25% trypsin-EDTA. Dissociated cells were centrifuged and resuspended in Dulbecco’s Modified Eagle’s Medium (DMEM) containing 10% FBS and 1% penicillin/streptomycin, and grown at 37 °C in a 5% CO2 incubator. After cell confluence (8–10 days), flasks were shaken in a rotator at 180 rpm overnight to purify astrocytes and medium was replaced with DMEM containing 3% FBS and 0.25 mM dibutyryl cAMP. Cultures were maintained for an additional 2 weeks. Cultures contained >95% astrocytes as shown by positive glial fibrillary acidic protein (GFAP) immunofluorescence.
Complement-dependent cytotoxicity (CDC)
Astrocyte cultures were trypsinized and plated onto 96-well microplates at 20,000 cells/well and grown for 48 h. Human complement and AQP4-IgG were added in Hank’s balanced salt solution (HBSS, pH 7.2; Invitrogen), and cells were incubated at 28 °C for 2 h for cytotoxicity measurement by the Alamar Blue assay (Invitrogen) as described .
Organotypic cerebellar slice cultures and ex vivo NMO model
Cerebellar slice cultures were prepared using an interface-culture method as described  with modification. Postnatal day 7 CD59+/+ and CD59−/− rats were decapitated and the whole cerebellum was removed, placed in ice-cold HBSS and embedded in 2% low-melting point agarose. Parasagittal slices of 300-μm thickness were cut using a vibrating microtome and placed on transparent, non-coated membrane inserts (Millipore, Millicell-CM 0.4-μm pores, 30-mm diameter) in six-well plates containing 1 mL culture medium (50% MEM, 25% HBSS, 25% horse serum, 1% penicillin-streptomycin, 0.65% glucose and 25 mM HEPES), with a thin film of culture medium covering slices. Slices were cultured in 5% CO2 at 37 °C for 7 days with medium change every 2 days. AQP4-IgG (or control human IgG) and human complement were added on day 7 and slices were fixed 24 h later in 4% paraformaldehyde (PFA) for whole-mount immunostaining.
Blood (200 μL) was collected into EDTA tubes for cell analysis and into tubes without anticoagulant for serum. To study complement-mediated erythrocyte lysis, 100 μL of fresh rat serum was placed in wells of a 96-well plate and acidified by addition of 10 μL of 0.2 N HCl to each well to give a pH of 6.5-6.8, as described . Erythrocytes (10 μL of 50% suspension in PBS) were added to each well, and hemolysis quantified by absorbance at 412 nm after 1 h incubation at 37 °C, referenced against zero and 100% lysis controls. Hematology parameters were measured using a Genesis Hematology Analyzer (Oxford Science, Oxford, CT).
Intracerebral injection model
AQP4-IgG (30 μg) was delivered by intracerebral injection as described  with modification. CD59+/+ and CD59−/− rats were anesthetized with ketamine (100 mg/kg) and xylazine (10 mg/kg) and mounted on a stereotaxic frame. A midline scalp incision was made and a burr hole of 1-mm diameter was drilled on each side of the skull 0.5 mm anterior and 3.5 mm lateral to the bregma. A glass pipette with 40-μm diameter tip was inserted at a depth of 5 mm to infuse AQP4-IgG (or control IgG) in a total volume of 3 μL over 10 min by pressure injection. After injection, the glass pipette was kept in place for 10 min before slow withdrawal (over 5 min) to prevent leaking. At day 7 rats were deeply anesthetized and transcardially perfused with 200 mL heparinized PBS and 200 mL of 4% PFA in PBS. Brains were removed and post-fixed for 4 h in 4% PFA and crytoprotected in 20% sucrose. Serial frozen coronal sections (thickness 7 μm) were cut on a cryostat.
Intracisternal injection model
AQP4-IgG was delivered by injection into the cisterna magna of CD59+/+ and CD59−/− rats. Rats were anesthetized as above, mounted on a stereotaxic frame, the cisterna magna was exposed, and a glass pipette with 40-μm tip diameter was inserted. AQP4-IgG or control IgG (15 or 30 μg in 10 μL artificial cerebrospinal fluid, aCSF) was infused at 2 μl/min over 5 min by pressure injection at 10 psi. In some experiments a recombinant monoclonal anti-AQP4 ‘aquaporumab’ lacking effector functions (AQP4-IgG-CDC)  was infused. After injection, the glass pipette was withdrawn with no leakage seen. At specified times, rats were euthanized as above, and brain, spinal cord and optic nerves were removed for sectioning. Rat motor function was scored as described  with modification: score 0 = normal movement; score 1, tail paralysis; score 2, hindlimb paralysis; score 3, hindlimb paralysis with frontlimb paresis; score 4, complete paralysis with moribund condition.
Cultured astrocytes and cerebellar slice cultures were fixed with 4% PFA for 15 min and incubated in blocking solution as described . Frozen sections of brain, spinal cord and other organs were post-fixed with 4% PFA for 5 min and incubated in blocking solution as described . Slides were then incubated for 2 h with antibodies against GFAP (1:200; Millipore), AQP4 (1:200, Santa Cruz Biotechnology), ionized calcium binding adaptor molecule 1 (Iba1; 1:400, Wako, Richmond, VA), CD45 (1:20, Cambridge, MA), C9neo (1:100, Santa Cruz Biotechnology), myelin basic protein (MBP, 1:100, Santa Cruz Biotechnology), human IgG (1:100, Santa Cruz Biotechnology), or CD59 (7A6, 5 μg/mL, LSBio, Seattle, WA), followed by the appropriate species-specific Alexa Fluor-conjugated secondary antibody for 1 h (5 μg/mL each, Invitrogen). Sections were mounted with VectaShield (Vector Laboratories, Burlingame, CA) for visualization of immunofluorescence on a Leica fluorescence microscope or Nikon confocal microscope.
Data are presented as mean ± S.E.M. Statistical analysis was performed using Prism 5 GraphPad Software package (San Diego, CA). The normality of the data was established by Bartlett’s test for equal variances and a one-way ANOVA with Newmann-Keuls post-hoc test to compare groups.
Generation and characterization of CD59−/− rats
Hematological parameters in CD59−/− and CD59+/+ rats
14.8 ± 0.5
8.7 ± 0.4
40.3 ± 1.5
13.3 ± 2.3
2 ± 0.1
7.5 ± 2.5
737 ± 165
14.3 ± 0.2*
7.8 ± 0.2*
38.5 ± 1.2*
14.2 ± 2*
12 ± 0.1*
7.4 ± 3.1
729 ± 188
We note an interesting observation made in carrying out control studies (of AQP4-IgG administration to CD59−/− rats) in which complement was inactivated by administration of cobra venom factor (350 units/kg), as we have done previously in CD59+/+ rats [1, 7]. All CD59−/− rats receiving cobra venom factor became moribund and died within 12–24 h, whereas no abnormalities were seen in CD59+/+ rats treated identically.
Marked complement-mediated injury in astrocyte cultures and brain slices from CD59−/− rats
To confirm the predicted greater sensitivity of a CD59−/− CNS tissue to development of complement-mediated NMO-like pathology, ex vivo cultured cerebellar slices from CD59+/+ and CD59−/− rats were incubated with AQP4-IgG and complement for 1 day. CD59−/− cerebellar slices showed astrocyte injury with loss of AQP4 and GFAP immunofluorescence, seen most prominently at the peripheral border, and deposition of activated complement as seen by C5b-9 immunofluorescence (Fig. 3c). In contract, minimal loss of AQP4 and GFAP, and complement deposition were seen in CD59+/+ cerebellar slices under the same experimental conditions.
Marked NMO pathology in brains of CD59−/− rats following intracerebral AQP4-IgG injection
NMO pathology in CNS tissues of CD59−/− rats following intracisternal AQP4-IgG injection
Immunofluorescence of spinal cord on day 3 showed marked loss of AQP4 and GFAP in cervical spinal cord of AQP4-IgG-treated CD59−/− rats, with patchy and variable loss in thoracic and lumbar spinal cord (Fig. 5c, d). Minimal loss of AQP4 and GFAP was seen in treated CD59+/+ rats. C5b-9 and Iba-1 immunofluorescence was seen in cervical and thoracic spinal cord in AQP4-IgG-treated CD59−/− rats (Fig. 5e). To investigate whether the location-dependent pathology in spinal cord is related to AQP4-IgG access and deposition, tissues from rats receiving 15 μg AQP4-IgG were harvested at 2 h and immunostained with an anti-human secondary antibody. Figure 5f shows detectable human IgG in cervical > thoracic spinal cord, with little seen in lumbar spinal cord.
Our study supports the central involvement of CD59 in modulating complement-mediated injury in AQP4-IgG seropositive NMO. CD59 is expressed in CNS tissues affected in NMO and may play a protective role to contain local, subclinical injury initiated by minor exposures to AQP4-IgG. CD59−/− rats were highly sensitive to passive transfer of AQP4-IgG by intracerebral and intracisternal routes, without the need for added components such as complement or pro-inflammatory factors. Though astrocytes may also express other complement regulator proteins such as CD55, the marked effect of CD59 gene deletion suggests that CD59 is the major complement regulator in rat brain. As an important complement regulator in astrocytes, drugs that enhance astrocytic CD59 expression, perhaps identifiable by compound screens, may be beneficial in NMO, and conversely, reduced astrocytic CD59 expression or subcellular colocalization with AQP4 might trigger NMO exacerbations and worsen disease severity.
Animal models of NMO have been useful in characterizing NMO pathogenesis mechanisms and for testing potential NMO therapeutics. Mouse models have been developed involving passive transfer of AQP4-IgG together with human complement by direct injections into the brain  or spinal fluid [3, 35] to produce NMO-like pathology in brain, spinal cord and optic nerve. As mentioned in the Introduction, a fundamental limitation of mice to study NMO is their lack of an effective classical complement activation pathway [5, 25]. Early rat models involved administration of AQP4-IgG following induction of experimental autoimmune encephalomyelitis (EAE) ; however, the pathogenic mechanism in EAE – myelin targeting by T cells – is very different from the humoral immune response in NMO, making it difficult to reach conclusions about NMO pathogenesis mechanisms. We found that intracerebral injection of AQP4-IgG produced robust NMO-like pathology in rat brain , and that while systemic administration of AQP4-IgG alone did not produce disease, NMO-like brain pathology was seen following a small needle stab in seropositive rats , which presumably allowed circulating AQP4-IgG leakage into brain parenchyma to access astrocytes, and perhaps produce a local inflammatory response. Creation of NMO spinal cord or optic nerve pathology in rats has been challenging. One study involving continuous AQP4-IgG infusion using intrathecal catheters showed reversible AQP4 loss in spinal cord but without inflammation or demyelination , and a similar more recent study reported AQP4 loss in spinal cord and optic nerves, as well as mildly reduction in myelin in spinal cord . The marked amplification of NMO pathology by knockout of CD59 in rats produced astrocytopathy as well as inflammation and deposition of activated complement.
CD59−/− rats did not manifest overt phenotypes, except for mild reticulocytosis and reduced hemoglobin, which is likely due to low-grade hemolysis as seen in humans lacking CD59  rather than a possible off-target effect in genome editing that can occur using CRISPR methods. The active classical complement system in rats, which has similar activity to that in human [5, 33], is presumably the reason for the low basal hemolytic activity. As such, CD59−/− rats may be useful to model complement-initiated diseases in various neurodegenerative, hematological, renal and skeletal muscle diseases [6, 11, 31]. Although the mechanism of high morbidity in CD59−/− rats receiving cobra venom factor was not established here, there appeared to be hemolysis and organ injury, which is likely due to complement activation and consumption by cobra venom factor, which is the mechanism of its complement depletion action [32, 33]. With regard to NMO, the amplified response of CD59−/− rats to AQP4-IgG may be useful in testing drugs that target distinct steps in the AQP4-IgG/complement injury pathway, as well as in investigating outstanding questions in NMO pathogenesis mechanisms such as the role of sensitized T cells and the explanation for the absence of significant pathology in peripheral AQP4-expressing tissues despite their sustained direct exposure to serum AQP4-IgG.
The marked NMO pathology seen in CD59−/− rats following AQP4-IgG administration contrasts with the conclusions of Saadoun and Papadopoulos , who concluded that complement inhibitors, including CD59, are not protective against complement injury in CNS tissues. Their findings were based on immunofluorescence in mouse brain in which CD59 expression was seen on astrocytes, but not at AQP4-rich foot-processes abutting microvessels. Detection sensitivity rather than species differences may account for the disparate conclusions, as we previously showed marked NMO pathology in CD59−/− mice following intracerebral or lumbosacral administration of AQP4-IgG with human complement . Our recent development of super-resolution microscopy methods to image AQP4 on astrocytes in fixed CNS tissues  may overcome the limited resolution and sensitivity of conventional fluorescence microscopy to detect CD59 in subcellular regions of astrocytes. Saadoun and Papadopoulos  also speculated that the absence of significant NMO disease in peripheral AQP4-expressing tissues such as skeletal muscle and kidney was a consequence of CD59 and AQP4 coexpression, which should be amenable to testing using CD59−/− rats.
In conclusion, our results implicate CD59 as an important regulator in NMO pathogenesis and potentially a new drug target with a novel mechanism of action to reduce complement-mediated astrocyte damage, a key initiating event in NMO. Prevention of complement-mediated astrocyte damage by altering astrocyte susceptibility to complement may have a more favorable side-effect profile than by general complement inhibition.
This work was supported by grants EY13574, EB00415, DK35124, and DK72517 from the National Institutes of Health, and a grant from the Guthy-Jackson Charitable Foundation. We thank Dr. Jeffrey Bennett (Univ. Colorado Denver, Aurora, CO) for providing recombinant monoclonal NMO antibodies and Tao Su (UCSF) for help in astrocyte and slice culture studies.
XY carried out experiments and analyses. XY and ASV designed studies and wrote the manuscript. Both authors read and approved the final manuscript.
The authors declare that they have no competing interests.
Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
- Asavapanumas N, Ratelade J, Verkman AS (2014) Unique neuromyelitis optica pathology produced in naive rats by intracerebral administration of NMO-IgG. Acta Neuropathol 127:539–551View ArticlePubMedGoogle Scholar
- Asavapanumas N, Verkman AS (2014) Neuromyelitis optica pathology in rats following intraperitoneal injection of NMO-IgG and intracerebral needle injury. Acta Neuropathol Commun 2:48View ArticlePubMedPubMed CentralGoogle Scholar
- Asgari N, Khorooshi R, Lillevang ST, Owens T (2013) Complement-dependent pathogenicity of brain-specific antibodies in cerebrospinal fluid. J Neuroimmunol 254:76–82View ArticlePubMedGoogle Scholar
- Bennett JL, Lam C, Kalluri SR, Saikali P, Bautista K, Dupree C, Glogowska M, Case D, Antel JP, Owens GP, Gilden D, Nessler S, Stadelmann C, Hemmer B (2009) Intrathecal pathogenic anti-aquaporin-4 antibodies in early neuromyelitis optica. Ann Neurol 66:617–629View ArticlePubMedPubMed CentralGoogle Scholar
- Bergman I, Basse PH, Barmada MA, Griffin JA, Cheung NK (2000) Comparison of in vitro antibody-targeted cytotoxicity using mouse, rat and human effectors. Cancer Immunol Immunother 49:259–266View ArticlePubMedGoogle Scholar
- Brodsky RA (2015) Complement in hemolytic anemia. Blood 126:2459–2465View ArticlePubMedGoogle Scholar
- Felix CM, Levin MH, Verkman AS (2016) Complement-independent retinal pathology produced by intravitreal injection of neuromyelitis optica immunoglobulin G. J Neuroinflammation 13:275View ArticlePubMedPubMed CentralGoogle Scholar
- Fujihara K (2011) Neuromyelitis optica and astrocytic damage in its pathogenesis. Journal of neurological sciences 306:183–187View ArticleGoogle Scholar
- Geis C, Ritter C, Ruschil C, Weishaupt A, Grunewald B, Stoll G, Holmoy T, Misu T, Fujihara K, Hemmer B, Stadelmann C, Bennett JL, Sommer C, Toyka KV (2015) The intrinsic pathogenic role of autoantibodies to aquaporin 4 mediating spinal cord disease in a rat passive-transfer model. Exp Neurol 265:8–21View ArticlePubMedGoogle Scholar
- Hengstman GJ, Wesseling P, Frenken CW, Jongen PJ (2007) Neuromyelitis optica with clinical and histopathological involvement of the brain. Mult Scler 13:679–682View ArticlePubMedGoogle Scholar
- Holers VM, Thurman JM (2004) The alternative pathway of complement in disease:opportunities for therapeutic targeting. Mol Immunol 41:147–152View ArticlePubMedGoogle Scholar
- Iwamoto N, Kawaguchi T, Nagakura S, Hidaka M, Horikawa K, Kagimoto T, Takatsuki K, Nakakuma H (1995) Markedly high population of affected reticulocytes negative for decay-accelerating factor and CD59 in paroxysmal nocturnal hemoglobinuria. Blood 85:2228–2232PubMedGoogle Scholar
- Jarius S, Wildemann B (2010) AQP4 antibodies in neuromyelitis optica: diagnostic and pathogenetic relevance. Nat Rev Neurol 6:383–392View ArticlePubMedGoogle Scholar
- Lennon VA, Kryzer TJ, Pittock SJ, Verkman AS, Hinson SR (2005) IgG marker of optic-spinal multiple sclerosis binds to the aquaporin-4 water channel. J Exp Med 202:473–477View ArticlePubMedPubMed CentralGoogle Scholar
- Li L, Zhang H, Varrin-Doyer M, Zamvil SS, Verkman AS (2011) Proinflammatory role of aquaporin-4 in autoimmune neuroinflammation. FASEB J 25:1556–1566View ArticlePubMedPubMed CentralGoogle Scholar
- Lucchinetti CF, Mandler RN, McGavern D, Bruck W, Gleich G, Ransohoff RM, Trebst C, Weinshenker B, Wingerchuk D, Parisi JE, Lassmann H (2002) A role for humoral mechanisms in the pathogenesis of Devic’s neuromyelitis optica. Brain 125:1450–1461View ArticlePubMedGoogle Scholar
- Marignier R, Ruiz A, Cavagna S, Nicole A, Watrin C, Touret M, Parrot S, Malleret G, Peyron C, Benetollo C, Auvergnon N, Vukusic S, Giraudon P (2016) Neuromyelitis optica study model based on chronic infusion of autoantibodies in rat cerebrospinal fluid. J Neuroinflammation 13:111View ArticlePubMedPubMed CentralGoogle Scholar
- Misu T, Fujihara K, Kakita A, Konno H, Nakamura M, Watanabe S, Takahashi T, Nakashima I, Takahashi H, Itoyama Y (2007) Loss of aquaporin 4 in lesions of neuromyelitis optica: distinction from multiple sclerosis. Brain 130:1224–1234View ArticlePubMedGoogle Scholar
- Papadopoulos MC, Verkman AS (2012) Aquaporin 4 and neuromyelitis optica. The Lancet Neurology 11:535–544View ArticlePubMedPubMed CentralGoogle Scholar
- Perez-Nievas BG, Garcia-Bueno B, Madrigal JL, Leza JC (2010) Chronic immobilisation stress ameliorates clinical score and neuroinflammation in a MOG-induced EAE in Dark Agouti rats: mechanisms implicated. J Neuroinflammation 7:60View ArticlePubMedPubMed CentralGoogle Scholar
- Pittock SJ, Lennon VA, McKeon A, Mandrekar J, Weinshenker BG, Lucchinetti CF, O’Toole O, Wingerchuk DM (2013) Eculizumab in AQP4-IgG-positive relapsing neuromyelitis optica spectrum disorders: an open-label pilot study. The Lancet Neurology 12:554–562View ArticlePubMedGoogle Scholar
- Pohl M, Fischer MT, Mader S, Schanda K, Kitic M, Sharma R, Wimmer I, Misu T, Fujihara K, Reindl M, Lassmann H, Bradl M (2011) Pathogenic T cell responses against aquaporin 4. Acta Neuropathol 122:21–34View ArticlePubMedPubMed CentralGoogle Scholar
- Qin X, Krumrei N, Grubissich L, Dobarro M, Aktas H, Perez G, Halperin JA (2003) Deficiency of the mouse complement regulatory protein mCd59b results in spontaneous hemolytic anemia with platelet activation and progressive male infertility. Immunity 18:217–227View ArticlePubMedGoogle Scholar
- Ratelade J, Asavapanumas N, Ritchie AM, Wemlinger S, Bennett JL, Verkman AS (2013) Involvement of antibody-dependent cell-mediated cytotoxicity in inflammatory demyelination in a mouse model of neuromyelitis optica. Acta Neuropathol 126:699–709View ArticlePubMedPubMed CentralGoogle Scholar
- Ratelade J, Verkman AS (2014) Inhibitor(s) of the classical complement pathway in mouse serum limit the utility of mice as experimental models of neuromyelitis optica. Mol Immunol 62:104–113View ArticlePubMedPubMed CentralGoogle Scholar
- Roemer SF, Parisi JE, Lennon VA, Benarroch EE, Lassmann H, Bruck W, Mandler RN, Weinshenker BG, Pittock SJ, Wingerchuk DM, Lucchinetti CF (2007) Pattern-specific loss of aquaporin-4 immunoreactivity distinguishes neuromyelitis optica from multiple sclerosis. Brain 130:1194–1205View ArticlePubMedGoogle Scholar
- Saadoun S, Papadopoulos MC (2015) Role of membrane complement regulators in neuromyelitis optica. Mult Scler 21:1644–1654View ArticlePubMedGoogle Scholar
- Saadoun S, Waters P, Bell BA, Vincent A, Verkman AS, Papadopoulos MC (2010) Intra-cerebral injection of neuromyelitis optica immunoglobulin G and human complement produces neuromyelitis optica lesions in mice. Brain 133:349–361View ArticlePubMedPubMed CentralGoogle Scholar
- Smith AJ, Verkman AS (2015) Superresolution imaging of aquaporin-4 cluster size in antibody-stained paraffin brain sections. Biophys J 109:2511–2522View ArticlePubMedPubMed CentralGoogle Scholar
- Tradtrantip L, Ratelade J, Zhang H, Verkman AS (2013) Enzymatic deglycosylation converts pathogenic neuromyelitis optica anti-aquaporin-4 immunoglobulin G into therapeutic antibody. Ann Neurol 73:77–85View ArticlePubMedGoogle Scholar
- Unsworth DJ (2008) Complement deficiency and disease. J Clin Pathol 61:1013–1017View ArticlePubMedGoogle Scholar
- Van den Berg CW, Aerts PC, Van Dijk H (1991) In vivo anti-complementary activities of the cobra venom factors from Naja naja and Naja haje. J Immunol Methods 136:287–294View ArticlePubMedGoogle Scholar
- Vogel CW, Fritzinger DC (2010) Cobra venom factor: Structure, function, and humanization for therapeutic complement depletion. Toxicon 56:1198–1222View ArticlePubMedGoogle Scholar
- Yao X, Su T, Verkman AS (2016) Clobetasol promotes remyelination in a mouse model of neuromyelitis optica. Acta Neuropathol Commun 4:42View ArticlePubMedPubMed CentralGoogle Scholar
- Zeka B, Hastermann M, Hochmeister S, Kogl N, Kaufmann N, Schanda K, Mader S, Misu T, Rommer P, Fujihara K, Illes Z, Leutmezer F, Sato DK, Nakashima I, Reindl M, Lassmann H, Bradl M (2015) Highly encephalitogenic aquaporin 4-specific T cells and NMO-IgG jointly orchestrate lesion location and tissue damage in the CNS. Acta Neuropathol 130:783–798View ArticlePubMedPubMed CentralGoogle Scholar
- Zeka B, Hastermann M, Kaufmann N, Schanda K, Pende M, Misu T, Rommer P, Fujihara K, Nakashima I, Dahle C, Leutmezer F, Reindl M, Lassmann H, Bradl M (2016) Aquaporin 4-specific T cells and NMO-IgG cause primary retinal damage in experimental NMO/SD. Acta Neuropathol Commun 4:82View ArticlePubMedPubMed CentralGoogle Scholar
- Zhang H, Verkman AS (2013) Eosinophil pathogenicity mechanisms and therapeutics in neuromyelitis optica. J Clin Invest 123:2306–2316View ArticlePubMedPubMed CentralGoogle Scholar
- Zhang H, Verkman AS (2014) Longitudinally extensive NMO spinal cord pathology produced by passive transfer of NMO-IgG in mice lacking complement inhibitor CD59. J Autoimmun 53:67–77View ArticlePubMedPubMed CentralGoogle Scholar