After the near eradication of polio, Guillain-Barre syndrome (GBS) is the commonest cause of acute flaccid paralysis. Anti-ganglioside/glycan antibodies (Abs) are the most frequently recognized autoimmune responses in immune neuropathies grouped under the term GBS. Despite the availability of two immunomodulatory therapies, a significant proportion of patients are left with permanent neurologic sequelae. Patients with neurologic sequelae almost always have failure of axon regeneration and target reinnervation. Several studies indicate that specific anti-glycan Abs associate with poor recovery. Our group examined the effects of anti- glycan Abs on peripheral nerve repair and found these Abs inhibit regeneration of injured axons in preclinical models. The overall goals of this translational project are to study mechanisms underlying pathobiologic effects of anti-ganglioside Abs on axon regeneration and to develop strategies that could prevent the deleterious effects of anti-glycan Abs on nerve repair. Our preliminary results show that specific activating Fc-gamma receptors (Fc?Rs) particularly on macrophages recruited in the injured nerves are key determinants of Ab-mediated inhibition of nerve repair. Further, glycosylation of anti-ganglioside Abs is critical in their interactions with Fc?Rs and deglycosylation of anti-glyca Abs suppresses their inhibitory effects on nerve repair. Further, sialylated- fraction of human intravenous immunoglobulins (sIVIG), a minor component of IVIG, suppresses Ab-mediated inhibition of axon regeneration. We hypothesize that anti-glycan Abs bind to gangliosides on neural cell surfaces to form immune complexes on the proximal tips of injured axons and these in turn bind to specific activating Fc?Rs expressed by adjacent glial cells to induce tissue inflammation affecting axon regeneration. Furthermore, IgG Fc interactions with innate immune receptors are critically dependent on the IgG glycosylation and this glycosylation status can be manipulated (on pathogenic Abs and IVIG) to alter anti- ganglioside Ab- or IVIG-mediated effects. This renewal application will test these hypotheses by the following specific aims:
Aim 1 will examine the role of specific Fc?Rs and glial cells expressing Fc?Rs in mediating nerve injury;
Aim 2 will examine the role of N-glycan structures, carried by anti-glycan Abs, in their interactions with Fc?Rs to induce inflammation;
and Aim 3 will examine the role of Fc/IgG sialylation as determinants of IVIG efficacy via the so-called 'DC-SIGN-Th2' anti-inflammatory pathway. These translational and 'proof of principle' studies have pathobiologic and therapeutic implications for failure of axon regeneration particularly that seen after immune insults/inflammation in autoimmune conditions like immune neuropathies and multiple sclerosis where failure of axonal repair is central to severity of the disease and recovery.

Public Health Relevance

Guillain-Barr? syndrome is the commonest cause of acute flaccid paralysis worldwide. This disease is strongly associated with autoantibodies directed against cell surface glycans called gangliosides. We show that these antibodies prevent successful nerve repair, which is necessary for recovery. This project proposes to examine immune mechanisms and cells involved in antibody-mediated inhibition of nerve repair. Strategies that suppress the Ab-mediated inflammation and prevent anti-glycan antibody-mediated inhibition of nerve repair will also be assessed. These studies may facilitate development of new therapies for patients with Guillain- Barr? syndrome.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
5R01NS054962-07
Application #
8874311
Study Section
Clinical Neuroimmunology and Brain Tumors Study Section (CNBT)
Program Officer
Nuckolls, Glen H
Project Start
2006-04-01
Project End
2019-04-30
Budget Start
2015-05-01
Budget End
2016-04-30
Support Year
7
Fiscal Year
2015
Total Cost
$332,500
Indirect Cost
$113,750
Name
University of Texas Health Science Center Houston
Department
Neurology
Type
Schools of Medicine
DUNS #
800771594
City
Houston
State
TX
Country
United States
Zip Code
77225
Gao, Tong; Bogdanova, Nataliia; Ghauri, Sameera et al. (2018) Systemic IGF-1 gene delivery by rAAV9 improves spontaneous autoimmune peripheral polyneuropathy (SAPP). Sci Rep 8:5408
Zhang, Gang; Lin, Jianxin; Ghauri, Sameera et al. (2017) Modulation of IgG-FcRn interactions to overcome antibody-mediated inhibition of nerve regeneration. Acta Neuropathol 134:321-324
Sheikh, Kazim A; Zhang, Gang (2016) Antibody-based neuronal and axonal delivery vectors for targeted ligand delivery. Neural Regen Res 11:712-4
Asthana, Pallavi; Vong, Joaquim Si Long; Kumar, Gajendra et al. (2016) Dissecting the Role of Anti-ganglioside Antibodies in Guillain-Barré Syndrome: an Animal Model Approach. Mol Neurobiol 53:4981-91
Zhang, Gang; Massaad, Cynthia A; Gao, Tong et al. (2016) Sialylated intravenous immunoglobulin suppress anti-ganglioside antibody mediated nerve injury. Exp Neurol 282:49-55
Rozés Salvador, Victoria; Heredia, Florencia; Berardo, Andrés et al. (2016) Anti-glycan antibodies halt axon regeneration in a model of Guillain Barrè Syndrome axonal neuropathy by inducing microtubule disorganization via RhoA-ROCK-dependent inactivation of CRMP-2. Exp Neurol 278:42-53
Nguyen, Thy P; Biliciler, Suur; Wiszniewski, Wojciech et al. (2015) Expanding Phenotype of VRK1 Mutations in Motor Neuron Disease. J Clin Neuromuscul Dis 17:69-71
Massaad, Cynthia A; Zhang, Gang; Pillai, Laila et al. (2015) Fluorescently-tagged anti-ganglioside antibody selectively identifies peripheral nerve in living animals. Sci Rep 5:15766
Vegosen, Leora; Breysse, Patrick N; Agnew, Jacqueline et al. (2015) Occupational Exposure to Swine, Poultry, and Cattle and Antibody Biomarkers of Campylobacter jejuni Exposure and Autoimmune Peripheral Neuropathy. PLoS One 10:e0143587
He, Lan; Zhang, Gang; Liu, Weiqiang et al. (2015) Anti-Ganglioside Antibodies Induce Nodal and Axonal Injury via Fc? Receptor-Mediated Inflammation. J Neurosci 35:6770-85

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