1
|
Tang Y, Qu S, Ning Z, Wu H. Immunopeptides: immunomodulatory strategies and prospects for ocular immunity applications. Front Immunol 2024; 15:1406762. [PMID: 39076973 PMCID: PMC11284077 DOI: 10.3389/fimmu.2024.1406762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Accepted: 07/01/2024] [Indexed: 07/31/2024] Open
Abstract
Immunopeptides have low toxicity, low immunogenicity and targeting, and broad application prospects in drug delivery and assembly, which are diverse in application strategies and drug combinations. Immunopeptides are particularly important for regulating ocular immune homeostasis, as the eye is an immune-privileged organ. Immunopeptides have advantages in adaptive immunity and innate immunity, treating eye immune-related diseases by regulating T cells, B cells, immune checkpoints, and cytokines. This article summarizes the application strategies of immunopeptides in innate immunity and adaptive immunity, including autoimmunity, infection, vaccine strategies, and tumors. Furthermore, it focuses on the mechanisms of immunopeptides in mediating ocular immunity (autoimmune diseases, inflammatory storms, and tumors). Moreover, it reviews immunopeptides' application strategies and the therapeutic potential of immunopeptides in the eye. We expect the immune peptide to get attention in treating eye diseases and to provide a direction for eye disease immune peptide research.
Collapse
Affiliation(s)
| | | | | | - Hong Wu
- Eye Center of Second Hospital of Jilin University, Changchun, China
| |
Collapse
|
2
|
Ley K. 2015 Russell Ross Memorial Lecture in Vascular Biology: Protective Autoimmunity in Atherosclerosis. Arterioscler Thromb Vasc Biol 2016; 36:429-38. [PMID: 26821946 PMCID: PMC4970520 DOI: 10.1161/atvbaha.115.306009] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 01/18/2016] [Indexed: 01/18/2023]
Abstract
Atherosclerosis is an inflammatory disease of the arterial wall. It is accompanied by an autoimmune response against apolipoprotein B-100, the core protein of low-density lipoprotein, which manifests as CD4 T cell and antibody responses. To assess the role of the autoimmune response in atherosclerosis, the nature of the CD4 T cell response against apolipoprotein B-100 was studied with and without vaccination with major histocompatibility complex-II-restricted apolipoprotein B-100 peptides. The immunologic basis of autoimmunity in atherosclerosis is discussed in the framework of theories of adaptive immunity. Older vaccination approaches are also discussed. Vaccinating Apoe(-/-) mice with major histocompatibility complex-II-restricted apolipoprotein B-100 peptides reduces atheroma burden in the aorta by ≈40%. The protective mechanism likely includes secretion of interleukin-10. Protective autoimmunity limits atherosclerosis in mice and suggests potential for developing preventative and therapeutic vaccines for humans.
Collapse
Affiliation(s)
- Klaus Ley
- From the La Jolla Institute for Allergy & Immunology and Department of Bioengineering, UCSD, La Jolla, CA
| |
Collapse
|
3
|
Heuss ND, Pierson MJ, Montaniel KRC, McPherson SW, Lehmann U, Hussong SA, Ferrington DA, Low WC, Gregerson DS. Retinal dendritic cell recruitment, but not function, was inhibited in MyD88 and TRIF deficient mice. J Neuroinflammation 2014; 11:143. [PMID: 25116321 PMCID: PMC4149240 DOI: 10.1186/s12974-014-0143-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2014] [Accepted: 07/29/2014] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Immune system cells are known to affect loss of neurons due to injury or disease. Recruitment of immune cells following retinal/CNS injury has been shown to affect the health and survival of neurons in several models. We detected close, physical contact between dendritic cells and retinal ganglion cells following an optic nerve crush, and sought to understand the underlying mechanisms. METHODS CD11c-DTR/GFP mice producing a chimeric protein of diphtheria toxin receptor (DTR) and GFP from a transgenic CD11c promoter were used in conjunction with mice deficient in MyD88 and/or TRIF. Retinal ganglion cell injury was induced by an optic nerve crush, and the resulting interactions of the GFPhi cells and retinal ganglion cells were examined. RESULTS Recruitment of GFPhi dendritic cells to the retina was significantly compromised in MyD88 and TRIF knockout mice. GFPhi dendritic cells played a significant role in clearing fluorescent-labeled retinal ganglion cells post-injury in the CD11c-DTR/GFP mice. In the TRIF and MyD88 deficient mice, the resting level of GFPhi dendritic cells was lower, and their influx was reduced following the optic nerve crush injury. The reduction in GFPhi dendritic cell numbers led to their replacement in the uptake of fluorescent-labeled debris by GFPlo microglia/macrophages. Depletion of GFPhi dendritic cells by treatment with diphtheria toxin also led to their displacement by GFPlo microglia/macrophages, which then assumed close contact with the injured neurons. CONCLUSIONS The contribution of recruited cells to the injury response was substantial, and regulated by MyD88 and TRIF. However, the presence of these adaptor proteins was not required for interaction with neurons, or the phagocytosis of debris. The data suggested a two-niche model in which resident microglia were maintained at a constant level post-optic nerve crush, while the injury-stimulated recruitment of dendritic cells and macrophages led to their transient appearance in numbers equivalent to or greater than the resident microglia.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | - Dale S Gregerson
- Department of Ophthalmology & Visual Neurosciences, University of Minnesota, Lions Research Bldg, Rm 314, 2001 6th St SE, Minneapolis 55455, MN, USA.
| |
Collapse
|
4
|
del Barco DG, Berlanga J, Penton E, Hardiman O, Montero E. Boosting controlled autoimmunity: a new therapeutic target for CNS disorders. Expert Rev Neurother 2014; 8:819-25. [DOI: 10.1586/14737175.8.5.819] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
5
|
Proliferative vitreoretinopathy may be a risk factor in combined macular hole retinal detachment cases. Retina 2013; 33:579-85. [PMID: 23222494 DOI: 10.1097/iae.0b013e31826b0c41] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
OBJECTIVE To review the incidence and closure rate of full-thickness macular holes (MH) in cases associated with concomitant rhegmatogenous retinal detachment (RRD). METHODS A retrospective consecutive case series was performed from patients undergoing surgical repair of RRD and simultaneous closure of MH. The presence of proliferative vitreoretinopathy (PVR), rates of hole closure and reattachment, and visual acuity outcomes were evaluated. RESULTS There were a total of 607 RRDs during the study period. The incidence of concomitant MH in RRD cases was 2.3% (14 of 607), and the overall incidence of PVR was 15.8% (96 of 607). All eyes with a MH had a primary break that was distinct from the MH. Five patients did not meet the inclusion criteria for review of the postoperative outcomes. In the remaining 9 patients, the retinal reattachment rate was 100%, and MH closure was achieved in 8 of 9 (89%) eyes after a single surgery. At the time of primary repair, PVR was present in 6 of these 9 cases (66.7%). There was a significant association between the presence of PVR and a concomitant MH (P = 0.0027). The mean preoperative visual acuity was 2.59 ± 0.649 logarithm of the minimum angle of resolution units and significantly improved to 1.23 ± 1.01 logarithm of the minimum angle of resolution units (P = 0.00124). Overall, 88.8% of patients showed an improvement in visual acuity at the final postoperative visit, and a visual acuity of 20/125 or better was achieved in 66.7% of cases. CONCLUSION Macular holes combined with a RRD are infrequent, and good anatomical results can be achieved after a simultaneous repair. Also, PVR may be more frequently encountered in this particular subset of RRDs.
Collapse
|
6
|
|
7
|
Doycheva D, Preuss B, Deuter C, Zierhut M, Klein R. Identification of immunodominant epitopes of alpha-crystallins recognized by antibodies in sera of patients with uveitis. Graefes Arch Clin Exp Ophthalmol 2011; 250:297-305. [PMID: 21842131 DOI: 10.1007/s00417-011-1758-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2010] [Revised: 06/03/2011] [Accepted: 07/28/2011] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND A high incidence of autoantibodies to lens proteins has been found in sera of patients with uveitis. We showed previously that the anti-lens antibodies reacted predominantly with α-crystallins. The aim of the present study was to identify immunodominant epitopes within the protein chains of human αA- and αB-crystallin. METHODS Epitope specificities of antibodies to αA- and αB-crystallin were examined by ELISA using synthetic overlapping peptides, spanning the entire length of both α-crystallins. The peptides consisted of 25 amino acid residues, with an overlap of at least eight amino acids each. The synthetic peptides were tested against sera of 110 patients with different uveitis forms, classified according to anatomical location of intraocular inflammation. RESULTS Four immunodominant regions within the protein chains of αA- and αB-crystallin could be identified. These regions were recognized by antibodies in sera of 56% of uveitis patients. Anti-lens antibodies of IgG-type reacted preferentially with regions located at amino acid (aa) residues aa:69-93 and aa:137-161 of αA-crystallin as well as aa:69-110 and aa:137-161 of αB-crystallin. IgM antibodies recognized predominantly region aa:149-173 of αA-crystallin, and aa:69-110 and aa:151-175 of αB-crystallin. IgM antibodies directed to peptide aa:69-93 of αB-crystallin were found in sera of 30% of patients with intermediate uveitis. CONCLUSIONS Four immunodominant B-cell epitopes within the protein chains of αA- and αB-crystallin have been identified; however, no clear correlation with the anatomically defined uveitis subtypes has been found except for intermediate uveitis. Whether there may be a correlation with uveitis forms with similar etiopathogenesis has to be evaluated in further studies.
Collapse
Affiliation(s)
- Deshka Doycheva
- Centre for Ophthalmology, University of Tuebingen, Schleichstr. 12, 72076 Tuebingen, Germany.
| | | | | | | | | |
Collapse
|
8
|
Schwartz M, London A. Erratum to: Immune maintenance in glaucoma: boosting the body's own neuroprotective potential. J Ocul Biol Dis Infor 2009; 2:104-108. [PMID: 20046842 PMCID: PMC2798980 DOI: 10.1007/s12177-009-9037-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Glaucoma, a slow progressive neurodegenerative disorder associated with death of retinal ganglion cells and degeneration of their connected optic nerve fibers, has been classically linked to high intraocular pressure. Regardless of the primary risk factor, degeneration may continue, resulting in further loss of neurons and subsequent glaucomatous damage. During the past decade, scientists and clinicians began to accept that, in addition or as an alternative to fighting off the primary risk factor(s), there is a need to protect the tissue from the ongoing spread of damage-an approach collectively termed "neuroprotection." We found that the immune system, the body's own defense mechanism, plays a key role in the ability of the optic nerve and the retina to withstand glaucomatous conditions. This defense involves recruitment of both innate and adaptive immune cells that together create a protective niche and thereby halt disease progression. The spontaneous immune response might not be sufficient, and therefore, we suggest boosting it by immunization (with the appropriate antigen, at specific timing and predetermined optimal dosing) which may be developed into a suitable therapeutic vaccination to treat glaucoma. This view of immune system involvement in glaucoma will raise new challenges in glaucoma research, changing the way in which clinicians perceive the disease and the approach to therapy.[This corrects the article on p. in vol. .].
Collapse
Affiliation(s)
- Michal Schwartz
- Department of Neurobiology, The Weizmann Institute of Science, Rehovot, Israel
| | - Anat London
- Department of Neurobiology, The Weizmann Institute of Science, Rehovot, Israel
| |
Collapse
|
9
|
Schwartz M, London A. Immune maintenance in glaucoma: boosting the body's own neuroprotective potential. J Ocul Biol Dis Infor 2009; 2:73-77. [PMID: 19672467 PMCID: PMC2723675 DOI: 10.1007/s12177-009-9025-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2009] [Accepted: 06/10/2009] [Indexed: 11/29/2022] Open
Abstract
Glaucoma, a slow progressive neurodegenerative disorder associated with death of retinal ganglion cells and degeneration of their connected optic nerve fibers, has been classically linked to high intraocular pressure. Regardless of the primary risk factor, degeneration may continue, resulting in further loss of neurons and subsequent glaucomatous damage. During the past decade, scientists and clinicians began to accept that, in addition or as an alternative to fighting off the primary risk factor(s), there is a need to protect the tissue from the ongoing spread of damage-an approach collectively termed "neuroprotection." We found that the immune system, the body's own defense mechanism, plays a key role in the ability of the optic nerve and the retina to withstand glaucomatous conditions. This defense involves recruitment of both innate and adaptive immune cells that together create a protective niche and thereby halt disease progression. The spontaneous immune response might not be sufficient, and therefore, we suggest boosting it by immunization (with the appropriate antigen, at specific timing and predetermined optimal dosing) which may be developed into a suitable therapeutic vaccination to treat glaucoma. This view of immune system involvement in glaucoma will raise new challenges in glaucoma research, changing the way in which clinicians perceive the disease and the approach to therapy.
Collapse
Affiliation(s)
- Michal Schwartz
- Department of Neurobiology, The Weizmann Institute of Science, Rehovot, Israel
| | - Anat London
- Department of Neurobiology, The Weizmann Institute of Science, Rehovot, Israel
| |
Collapse
|
10
|
Behavioral immunization: immunity to self-antigens contributes to psychological stress resilience. Mol Psychiatry 2009; 14:532-6. [PMID: 18779818 DOI: 10.1038/mp.2008.103] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The psychobiological mechanisms that contribute to the development of stress resilience are not fully elucidated. One potential approach for enhancing resilience is the exposure to mild challenges. According to this approach, a mildly stressful episode may immunize the individual, thereby strengthening resistance to subsequent stressors. This phenomenon is often viewed as a form of behavioral immunization. Although, the term 'behavioral immunization' was borrowed from the field of immunology, the involvement of the adaptive immune system in stress resilience was never investigated. However, based on accumulated new data, we suggest that the immunological memory does have a significant role in developing coping responses to stress. Although, immune deficiency results in an impaired ability to cope with stress, boosting immunological memory can increase stress resilience. Therefore, we propose that defense against mental challenge, similarly to defense against intruders, involves an immunological mechanism, which establishes stress resilience to a later challenge. Here, we review the involvement of the adaptive immune system in coping mechanisms in response to psychological stress, and discuss the connection between cognitive memory and immunological memory in establishing ability to efficiently cope with stressful episodes.
Collapse
|
11
|
Garg SK, Banerjee R, Kipnis J. Neuroprotective immunity: T cell-derived glutamate endows astrocytes with a neuroprotective phenotype. THE JOURNAL OF IMMUNOLOGY 2008; 180:3866-73. [PMID: 18322194 DOI: 10.4049/jimmunol.180.6.3866] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A well-controlled T cell response to CNS injury may result in increased neuronal survival. However, the precise mechanism of T cell-induced neuroprotection is unknown. In this study, we report the unexpected finding that during culture of T cells, high levels of glutamate accumulate, which are efficiently cleared if T cells are cocultured with astrocytes. The T cell-derived glutamate elicits in turn, the release of neuroprotective thiols (cysteine, glutathione, and cysteinyl-glycine) and lactate from astrocytes. Media obtained from astrocytes conditioned in the presence of T cells reduce neuronal apoptosis induced by oxidative stress in primary neuronal cultures from 48 +/- 14 to 9 +/- 4% (p < 0.001). Inhibition of glutamate-dependent signaling during astrocyte-T cell cocultivation by a glutamate uptake inhibitor, l-aspartic acid beta-hydroxamate, abolishes this neuroprotective effect. The ability of astrocytes to clear extracellular glutamate is impaired under conditions of oxidative stress. We demonstrate that T cells, via secreted cytokines, restore glutamate clearance capacity of astrocytes under oxidative conditions. Furthermore, under normoxic conditions, glutamate-buffering capacity of astrocytes is increased upon cocultivation with T cells. It is known that, following CNS injury, astrocytes can respond with beneficial or destructive effects on neurons. However, the context and signaling mechanisms for this dual astrocytic response are unknown. Our results implicate T cells as potential determinants of the context that elicits a protective role for astrocytes in the damaged CNS.
Collapse
Affiliation(s)
- Sanjay K Garg
- Redox Biology Center, University of Nebraska, Lincoln, NE 68588, USA
| | | | | |
Collapse
|
12
|
Belokopytov M, Ben-Shlomo G, Rosner M, Belkin M, Dubinski G, Epstein Y, Ofri R. Functional efficacy of glatiramer acetate treatment for laser-induced retinal damage in rats. Lasers Surg Med 2008; 40:196-201. [DOI: 10.1002/lsm.20610] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
|
13
|
Schwartz M, London A. Glaucoma as a neuropathy amenable to neuroprotection and immune manipulation. PROGRESS IN BRAIN RESEARCH 2008; 173:375-84. [DOI: 10.1016/s0079-6123(08)01126-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
|
14
|
Cohen H, Ziv Y, Cardon M, Kaplan Z, Matar MA, Gidron Y, Schwartz M, Kipnis J. Maladaptation to mental stress mitigated by the adaptive immune system via depletion of naturally occurring regulatory CD4+CD25+ cells. ACTA ACUST UNITED AC 2007; 66:552-63. [PMID: 16555237 DOI: 10.1002/neu.20249] [Citation(s) in RCA: 133] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Peripheral cellular immunity was recently shown to play a critical role in brain plasticity and performance. The antigenic specificity of the participating T cells, however, was not investigated, and nor was their relevance to psychological stress. Here we show, using a mouse model, that adaptive immunity mitigates maladaptation to the acute psychological stress known to trigger abnormal behaviors reminiscent of human post-traumatic stress disorder. Assessment of behavioral adaptation (measured by the acoustic startle response and avoidance behavior) in mice after their exposure to predator odor revealed that maladaptation was several times more prevalent in T cell-deficient mice than in their wild-type counterparts. A single population of T cells reactive to central nervous system (CNS)-associated self-protein was sufficient to endow immune-deficient mice with the ability to withstand the psychological stress. Naturally occurring CD4+CD25+ regulatory T cells were found to suppress this endogenous anti-stress attribute. These findings suggest that T cells specific to abundantly expressed CNS antigens are responsible for brain tissue homeostasis and help the individual to cope with stressful life episodes. They might also point the way to development of immune-based therapies for mental disorders, based either on up-regulation of T cells that partially cross-react with self-antigens or on weakening of the activity of regulatory T cells.
Collapse
MESH Headings
- Adaptation, Physiological/immunology
- Adaptation, Psychological/physiology
- Animals
- Autoimmunity/immunology
- CD4-Positive T-Lymphocytes/immunology
- Central Nervous System/immunology
- Disease Models, Animal
- Down-Regulation/immunology
- Immune Tolerance/immunology
- Immunity, Cellular/immunology
- Interleukin-2 Receptor alpha Subunit/immunology
- Male
- Mice
- Mice, Inbred BALB C
- Mice, SCID
- Mice, Transgenic
- Myelin Basic Protein/immunology
- Nerve Tissue Proteins/immunology
- Stress Disorders, Post-Traumatic/immunology
- Stress Disorders, Post-Traumatic/physiopathology
- Stress, Psychological/immunology
- Stress, Psychological/physiopathology
Collapse
Affiliation(s)
- Hagit Cohen
- Ministry of Health Mental Health Center Anxiety and Stress Research Unit, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | | | | | | | | | | | | | | |
Collapse
|
15
|
Ibarra A, Jiménez A, Cortes C, Correa D. Influence of the intensity, level and phase of spinal cord injury on the proliferation of T cells and T-cell-dependent antibody reactions in rats. Spinal Cord 2006; 45:380-6. [PMID: 16955070 DOI: 10.1038/sj.sc.3101972] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
STUDY DESIGN Three independent experiments in a rat model of contusive spinal cord (SC) injury were performed. Two studied the alterations induced by SC injury on some immunological aspects of the T-cell response. The third one evaluated the motor recovery of rats with low-thoracic injuries. OBJECTIVE To examine the effect of level, intensity and phase of SC injury on T-cell proliferation and T-cell-dependent antibody response. SETTING Neuroimmunology Department, UIMEN, IMSS-CAMINA Research Center. METHODS Lymphocyte proliferation and hemagglutination assays were performed. Animals were injured either moderately or severely at T1 or T12 SC segments. Analysis of peripheral T-cell proliferation in response to mitogens and to myelin basic protein (MBP), as well as of antibody production against a T-dependent antigen, was performed at acute, subacute and chronic phases. RESULTS A significant decrease of both response to mitogens and antibody production was found especially during the acute phase and in animals with severe and high (T1)-level injury. Animals with low (T12) and moderate contusions recovered to control levels at the chronic phase. An autoimmune reaction against MBP was observed only in animals with severe contusion at low level. CONCLUSIONS The intensity, level and phase of SC injury differentially alter the function of T cells. These results will allow a better interpretation of studies directed to elucidate the role of T lymphocytes in various processes developed after SC injury.
Collapse
Affiliation(s)
- A Ibarra
- Unidad de Investigación Médica en Enfermedades Neurológicas, HE, CMN Siglo XXI, IMSS, Col. Doctores, México City, México
| | | | | | | |
Collapse
|
16
|
Ben Simon GJ, Bakalash S, Aloni E, Rosner M. A rat model for acute rise in intraocular pressure: immune modulation as a therapeutic strategy. Am J Ophthalmol 2006; 141:1105-11. [PMID: 16765680 DOI: 10.1016/j.ajo.2006.01.073] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2005] [Revised: 01/24/2006] [Accepted: 01/24/2006] [Indexed: 11/24/2022]
Abstract
PURPOSE To establish a rat model of acute increase in intraocular pressure (IOP) and to investigate the therapeutic window for protection against death of retinal ganglion cells (RGCs) by vaccination with glatiramer acetate (Cop-1) or by treatment with brimonidine or MK-801. DESIGN Animal study, laboratory investigation. METHODS IOP was transiently increased in anesthetized Lewis rats by infusing normal saline (0.9%) into the anterior chamber of the eye for one hour. RGC survival was assessed one week and two weeks later by counting the RGCs retrogradely labeled with rhodamine dextran. MAIN OUTCOME MEASURES RGC survival. RESULTS IOP rose to 100 cm H(2)O (76 mm Hg) and returned to baseline after 24 hours. The RGC count decreased by 23% a week after the insult and by a further 7% after the second week. Vaccination with Cop-1 on the day of the insult prevented 50% of the IOP-induced RGC loss. Similar neuroprotection was achieved by daily intraperitoneal injections of brimonidine, but not with MK-801. CONCLUSIONS A transient increase in IOP to 100 cm H(2)O causes death of RGCs in rats. A single immunization with Cop-1 or daily injections of brimonidine protected up to 50% of potentially doomed RGCs from IOP-induced death, suggesting that not all of the cell death in the untreated model results from the IOP insult directly, but that some of it is caused by insult-induced environmental cytotoxicity, which is unrelated to glutamate toxicity or at least to NMDA receptors. These findings can be applied immediately as a basis for acute glaucoma therapy.
Collapse
Affiliation(s)
- Guy J Ben Simon
- Department of Neurobiology, The Weizmann Institute of Science, Rehovot, Israel.
| | | | | | | |
Collapse
|
17
|
Schwartz M, Yoles E. Immune-Based Therapy for Spinal Cord Repair: Autologous Macrophages and Beyond. J Neurotrauma 2006; 23:360-70. [PMID: 16629622 DOI: 10.1089/neu.2006.23.360] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Spinal cord injury is a devastating condition of the central nervous system (CNS), often resulting in severe loss of tissue, functional impairment, and only limited repair. Studies over the last few years have shown that response to the insult and spontaneous attempts at repair are multiphasic processes, with varying and sometimes conflicting requirements. This knowledge has led to novel strategies of therapeutic intervention. Our view is that a pivotal role in repair, maintenance, healing, and cell renewal in the CNS, as in other tissues, is played by the immune system. The mode and timing of intervention must be carefully selected, however, as the capacity of the CNS to tolerate local repair mechanisms is limited. Studies have shown that the spontaneously evoked early innate response to CNS injury is characterized by invasion of neutrophils and is unfavorable for cell survival. This is followed by a response of the resident innate immune cells (microglia), which however cannot supply all the needs of the damaged tissue; moreover, once evoked, and for as long as the damage persists, the microglial response remains beyond the capacity of the CNS to tolerate it. Immune-based clinical intervention is most effective in improving functional and morphological recovery when delayed for a certain period. Effective intervention might be in the form of (1) local injection of "alternatively activated" macrophages, (2) systemic injection of dendritic cells specific to CNS antigens, or (3) T-cell-based vaccination. The treatment of choice depends on the severity of the insult, the site of injury, the therapeutic window, and safety considerations.
Collapse
Affiliation(s)
- Michal Schwartz
- Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel.
| | | |
Collapse
|
18
|
Stahl D. Warm Autoimmune Hemolytic Anemia: A Clinical Model to Study Mechanisms of Immunoregulation*. Transfus Med Hemother 2006. [DOI: 10.1159/000091108] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
|
19
|
Kipnis J, Cardon M, Strous RD, Schwartz M. Loss of autoimmune T cells correlates with brain diseases: possible implications for schizophrenia? Trends Mol Med 2006; 12:107-12. [PMID: 16469540 DOI: 10.1016/j.molmed.2006.01.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2005] [Revised: 01/16/2006] [Accepted: 01/25/2006] [Indexed: 11/28/2022]
Abstract
T-cell-mediated autoimmunity participates in physiological defense, maintenance and repair of the adult brain. However, unless such autoimmune responses to insults are rigorously controlled, they might lead to an autoimmune disease or other immune-related defects, where destructive activity outweighs the beneficial effect. Here, we discuss these apparently contradictory effects of autoimmunity in schizophrenic patients, whose typical immune aberrations have prompted recent speculation about an autoimmune-related etiology. We found that, although schizophrenic patients have active immune systems, they often lack autoimmune clones specifically reactive to a major myelin protein, myelin basic protein (MBP). This, in conjunction with our discovery in rodents that T cells that recognize brain-resident proteins are needed for normal cognitive functioning, led us to propose an immune-based neurodevelopmental hypothesis, in which autoimmune-T-cell deficiency is suggested to cause onset or progression of schizophrenia.
Collapse
Affiliation(s)
- Jonathan Kipnis
- Department of Neurobiology, The Weizmann Institute of Science, 76100 Rehovot, Israel.
| | | | | | | |
Collapse
|
20
|
Does Inflammation in an Autoimmune Disease Differ from Inflammation in Neurodegenerative Diseases? Possible Implications for Therapy. J Neuroimmune Pharmacol 2006; 1:4-10. [DOI: 10.1007/s11481-005-9010-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
|
21
|
Schwartz M, Butovsky O, Brück W, Hanisch UK. Microglial phenotype: is the commitment reversible? Trends Neurosci 2006; 29:68-74. [PMID: 16406093 DOI: 10.1016/j.tins.2005.12.005] [Citation(s) in RCA: 328] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2005] [Revised: 10/26/2005] [Accepted: 12/15/2005] [Indexed: 11/22/2022]
Abstract
Microglia, the standby cells for immune defense in the CNS, have a reputation for exacerbating the neural damage that occurs in neurodegenerative diseases. However, research over the past few years has established that microglia do not constitute a single, uniform cell population, but rather comprise a family of cells with diverse phenotypes--some that are beneficial and others that the CNS can barely tolerate and that are therefore destructive. This finding raised several questions. What instructs microglia to acquire a particular phenotype, and how do these phenotypes differ? How committed are microglia to a specific phenotype? Can destructive microglia become protective, and can protective microglia retain their beneficial phenotype even when they encounter a destructive environment? Here, we address these questions, and the background of research that elicited them.
Collapse
Affiliation(s)
- Michal Schwartz
- The Weizmann Institute of Science, POB 26, Rehovot, 76100, Israel.
| | | | | | | |
Collapse
|
22
|
Schwartz M. Are neurodegenerative disorders systemic diseases? Outlook for future immune-based therapies. FUTURE NEUROLOGY 2006. [DOI: 10.2217/14796708.1.1.41] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The prevalence of neurodegenerative diseases increases exponentially with age. Increasing life expectancies in Western countries have, therefore, been accompanied by a growing increase in the number of victims, and in the future we can expect to see an increased number of the geriatric population suffering from these diseases. Despite improvements in our understanding of the pathogeneses, the prospects for finding a cure remain bleak. Many questions remain unanswered: are we dealing with a family of diseases or with individual unrelated syndromes? Is there a systemic malfunction that operates via a common pathway but affects different tissues or organs in different individuals? How will the answers to these questions affect future therapy?
Collapse
|
23
|
|
24
|
Butovsky O, Talpalar AE, Ben-Yaakov K, Schwartz M. Activation of microglia by aggregated beta-amyloid or lipopolysaccharide impairs MHC-II expression and renders them cytotoxic whereas IFN-gamma and IL-4 render them protective. Mol Cell Neurosci 2005; 29:381-93. [PMID: 15890528 DOI: 10.1016/j.mcn.2005.03.005] [Citation(s) in RCA: 269] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2004] [Revised: 03/13/2005] [Accepted: 03/15/2005] [Indexed: 11/23/2022] Open
Abstract
'Protective autoimmunity' refers to a well-controlled anti-self response that helps the body resist neurodegeneration. The response is mediated by autoimmune T cells, which produce cytokines and growth factors. Using an in vitro assay of hippocampal slices, we show that the cytokines interferon-gamma and (especially) interleukin-4, characteristic of pro-inflammatory and anti-inflammatory T cells, respectively, can make microglia neuroprotective. Aggregated beta-amyloid, like bacterial cell wall-derived lipopolysaccharide, rendered the microglia cytotoxic. Cytotoxicity was correlated with a signal transduction pathway that down-regulates expression of class-II major histocompatibility proteins (MHC-II) through the MHC-II-transactivator and the invariant chain. Protection by interleukin-4 was attributed to down-regulation of tumor necrosis factor-alpha and up-regulation of insulin-like growth factor I. These findings suggest that beneficial or harmful expression of the local immune response in the damaged CNS depends on how microglia interpret the threat, and that a well-regulated T-cell-mediated response enables microglia to alleviate rather than exacerbate stressful situations in the CNS.
Collapse
Affiliation(s)
- Oleg Butovsky
- Department of Neurobiology, The Weizmann Institute of Science, 76100 Rehovot, Israel
| | | | | | | |
Collapse
|
25
|
Bakalash S, Ben-Shlomo G, Shlomo GB, Aloni E, Shaked I, Wheeler L, Ofri R, Schwartz M. T-cell-based vaccination for morphological and functional neuroprotection in a rat model of chronically elevated intraocular pressure. J Mol Med (Berl) 2005; 83:904-16. [PMID: 16096740 DOI: 10.1007/s00109-005-0689-6] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2004] [Accepted: 04/10/2005] [Indexed: 10/25/2022]
Abstract
Acute or chronic glaucoma is often associated with an increase in intraocular pressure (IOP). In many patients, however, therapeutic pressure reduction does not halt disease progression. Neuroprotection has been proposed as a complementary therapeutic approach. We previously demonstrated effective T-cell-based neuroprotection in experimental animals vaccinated with the synthetic copolymer glatiramer acetate (copolymer-1, Cop-1), a weak agonist of self-antigens. This study was undertaken to test different routes and modes of vaccination with Cop-1 as treatment modalities for protection against retinal ganglion cell (RGC) death caused by chronic elevation of IOP in rats, and to determine whether anatomical neuroprotection is accompanied by functional neuroprotection. In a chronic model of unilaterally high IOP, Cop-1 vaccination, with or without an adjuvant, protected rats against IOP-induced loss of RGCs by eliciting a systemic T-cell-mediated response capable of cross-reacting with self-antigens residing in the eye. In rats deprived of T cells, Cop-1 (unlike treatment with alpha2-adrenoreceptor agonists) was not protective of RGCs, substantiating the contention that its beneficial effect is not conferred directly but is T-cell-mediated. Pattern electroretinography provided evidence of functional protection. Thus, vaccination with adjuvant-free Cop-1 can protect RGCs from the consequences of elevated IOP in rats. This protection is manifested both morphologically and functionally. These findings can be readily implemented for the development of a therapeutic vaccination to arrest the progression of glaucoma.
Collapse
Affiliation(s)
- Sharon Bakalash
- Department of Neurobiology, The Weizmann Institute of Science, 76100, Rehovot, Israel,
| | | | | | | | | | | | | | | |
Collapse
|
26
|
Schori H, Robenshtok E, Schwartz M, Hourvitz A. Post-intoxication vaccination for protection of neurons against the toxicity of nerve agents. Toxicol Sci 2005; 87:163-8. [PMID: 15976190 DOI: 10.1093/toxsci/kfi237] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Nerve agents are highly toxic organophosphates (OPs) that can cause severe damage to the central and peripheral nervous systems. The central nervous system insult results in seizures and neuronal death. The glutamatergic system apparently contributes to the neuropathology. Using a model of OP intoxication causing death of retinal ganglion cells in the mouse eye, we show here that intoxication is exacerbated if the mice are devoid of mature T cells. The retinal neurons could be protected from these effects by vaccination, 7 days before or immediately after intoxication, with the copolymer glatiramer acetate (Cop-1), recently found to limit the usual consequences of an acute glutamate insult to the eye. These findings underlie a new therapeutic approach to protection against OP intoxication, based on the rationale that boosting of the adaptive immunity recruited at the site of intoxication helps the local cellular machinery such as resident microglia to withstand the neurotoxic effects.
Collapse
Affiliation(s)
- Hadas Schori
- Department of Neurobiology, The Weizmann Institute of Science, 76100 Rehovot, Israel
| | | | | | | |
Collapse
|
27
|
Oppenheim JJ, Dong HF, Plotz P, Caspi RR, Dykstra M, Pierce S, Martin R, Carlos C, Finn O, Koul O, Howard OMZ. Autoantigens act as tissue-specific chemoattractants. J Leukoc Biol 2005; 77:854-61. [PMID: 15917448 DOI: 10.1189/jlb.1004623] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
We have investigated the chemoattractant properties of self-antigens associated with autoimmune diseases and solid tumors. Many autoantigens induced leukocyte migration, especially by immature dendritic cells (iDC) by interacting with various chemoattractant Gi-protein-coupled receptors (GiPCR). Our initial observation that myositis-associated autoantigens, histidyl-tRNA synthetase and asparaginyl-tRNA synthetase, were chemotactic for CC chemokine receptor 5 (CCR5)- and CCR3-expressing leukocytes, while other nonautoantigenic aminoacyl-tRNA synthesases were not, suggested that only self-antigens capable of interacting with receptors on antigen-presenting cells were immunogenic. We next determined that self-antigens associated with autoimmune diseases, e.g., multiple sclerosis or experimental autoimmune encephalomyelitis, type I diabetes, scleroderma, systemic lupus erythematosus, autoimmune uveitis, or experimental autoimmune uveitis (EAU), were chemotactic for GiPCR expressed by iDC. The majority of autoantigens were DC chemoattractants at 10-100 ng/ml, but did not induce DC maturation until they reached 1000-fold higher concentrations. Interphotoreceptor retinoid-binding protein and retinal arrestin (S-antigen) are targets of autoantibodies in human uveitis and are chemotactic for CXC chemokine receptor 5 (CXCR5)- and/or CXCR3-expressing iDC. However, although S-antigen does not induce EAU in wild-type mice, it is nevertheless a chemoattractant for murine iDC. These unexpected observations suggested that the chemotactic activity of these tissue-specific self-antigens could be involved in promotion of tissue repair and restoration. Thus, the primary role of autoantigens may be to alert the immune system to danger signals from invaded and damaged tissues to facilitate repair, and autoimmune responses subsequently develop only in subjects with impaired immunoregulatory function.
Collapse
Affiliation(s)
- Joost J Oppenheim
- National Cancer Institute-Frederick, Center for Cancer Research, Laboratory of Molecular Immunoregulation, MD 21702-1201, USA.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Shaked I, Tchoresh D, Gersner R, Meiri G, Mordechai S, Xiao X, Hart RP, Schwartz M. Protective autoimmunity: interferon-gamma enables microglia to remove glutamate without evoking inflammatory mediators. J Neurochem 2005; 92:997-1009. [PMID: 15715651 DOI: 10.1111/j.1471-4159.2004.02954.x] [Citation(s) in RCA: 164] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Glutamate in excessive amounts is a major contributor to neuronal degeneration, and its removal is attributed mainly to astrocytes. Traumatic injury to the central nervous system (CNS) is often accompanied by disappearance of astrocytes from the lesion site and failure of the remaining cells to withstand the ensuing toxicity. Microglia that repopulate the lesion site are the usual suspects for causing redox imbalance and inflammation and thus further exacerbating the neurotoxicity. However, our group recently demonstrated that early post-injury activation of microglia as antigen-presenting cells correlates with an ability to withstand injurious conditions. Moreover, we found that T cells reactive to CNS-specific self-antigens protected neurons against glutamate toxicity. Here, we show that antigen-specific autoimmune T cells, by tailoring the microglial phenotype, can increase the ability of microglia-enriched cultures to remove glutamate. This T-cell-mediated effect could not be achieved by the potent microglia-activating agent lipopolysaccharide (LPS), but was dose-dependently reproduced by the Th1 cytokine interferon (IFN)-gamma and significantly reduced by neutralizing anti-IFN-gamma antibodies. Under the same conditions, IFN-gamma had no effect on cultured astrocytes. Up-regulation of glutamate uptake induced by IFN-gamma activation was not accompanied by the acute inflammatory response seen in LPS-activated cultures. These findings suggest that T cells or their cytokines can cause microglia to adopt a phenotype that facilitates rather than impairs glutamate clearance, possibly contributing to restoration of homeostasis.
Collapse
Affiliation(s)
- I Shaked
- Department of Neurobiology, The Weizmann Institute of Science, Rehovot, Israel
| | | | | | | | | | | | | | | |
Collapse
|
29
|
Avidan H, Kipnis J, Butovsky O, Caspi RR, Schwartz M. Vaccination with autoantigen protects against aggregated beta-amyloid and glutamate toxicity by controlling microglia: effect of CD4+CD25+ T cells. Eur J Immunol 2005; 34:3434-45. [PMID: 15549735 DOI: 10.1002/eji.200424883] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Neurodegenerative diseases differ in etiology but are propagated similarly. We show that neuronal loss caused by intraocular injection of aggregated beta-amyloid was significantly greater in immunodeficient mice than in normal mice. The neurodegeneration was attenuated or augmented by elimination or addition, respectively, of naturally occurring CD4(+)CD25(+) regulatory T cells (Treg). Vaccination with retina-derived antigens or with the synthetic copolymer glatiramer acetate (Copolymer-1, Cop-1), but not with beta-amyloid, reduced the ocular neuronal loss. In mouse hippocampal slices, microglia encountering activated T cells overcame the cytotoxicity of aggregated beta-amyloid. These findings support the concept of "protective autoimmunity", show that a given T cell-based vaccination is protective at a particular site irrespective of toxicity type, and suggest that locally activated T cells induce a microglial phenotype that helps neurons withstand the insult. Alzheimer's and other neurodegenerative diseases might be arrested or retarded by vaccination with Cop-1 or related compounds or by treatment with compounds that weaken Treg suppression.
Collapse
Affiliation(s)
- Hila Avidan
- Department of Neurobiology, The Weizmann Institute of Science, Rehovot, Israel
| | | | | | | | | |
Collapse
|
30
|
Vallochi AL, da Silva Rios L, Nakamura MV, Silveira C, Muccioli C, Martins MC, Belfort R, Rizzo LV. The involvement of autoimmunity against retinal antigens in determining disease severity in toxoplasmosis. J Autoimmun 2005; 24:25-32. [PMID: 15725573 DOI: 10.1016/j.jaut.2004.11.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2004] [Revised: 11/04/2004] [Accepted: 11/10/2004] [Indexed: 11/21/2022]
Abstract
PURPOSE Ocular lesions are frequent in various individuals infected with Toxoplasma gondii. Disease intensity in ocular toxoplasmosis varies greatly between patients. Autoimmunity has been suggested as a possible component to retinal destruction. METHODS Immunologic parameters in the response to retina antigens were evaluated in infected persons with and without ocular lesions and in non-infected controls. Subjects were divided into groups on the basis of titers of serum antibodies to T. gondii, presence and severity of ocular lesions, and clinical history. RESULTS Peripheral blood mononuclear cells from patients with mild disease responded to one or more retinal antigens with a significantly higher frequency than patients without disease or with severe disease. Interestingly, the cytokines produced by the proliferating mononuclear cells did not follow any specific patterns, except for the fact that IL-4 and IL-5 were seldom detected. CONCLUSIONS Our results suggest that although the presence of an immune response towards autoantigens is not protective against the development of ocular lesions by the T. gondii, it may protect against the development of severe disease.
Collapse
Affiliation(s)
- Adriana Lima Vallochi
- Department of Immunology, Instituto de Ciências Biomédicas, Universidade de São Paulo, Av Prof Lineu Prestes 1730, São Paulo, Brazil.
| | | | | | | | | | | | | | | |
Collapse
|
31
|
Schwartz M, Kipnis J. A common vaccine for fighting neurodegenerative disorders: recharging immunity for homeostasis. Trends Pharmacol Sci 2004; 25:407-12. [PMID: 15276709 DOI: 10.1016/j.tips.2004.06.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Neurodegenerative conditions share common primary risk factors and mediators of disease progression. Because many degenerative disorders are age related, deteriorating immunity in aging patients might impose additional risk. Adaptive (T-cell-mediated) immunity is a defense mechanism that instructs microglia to fight off and clear away self-derived enemies. Such adaptive immunity can be boosted, without risking the development of autoimmune disease, by injecting weak agonists of self-antigens or by weakening the suppressive CD4+CD25+ regulatory T cells. If widely cross-reactive, the agonist might effectively counteract a variety of neurodegenerative disorders. Boosting of relevant T cells by vaccination could thus "recharge" a deteriorating immune system that has to contend with an increasing number of risk factors.
Collapse
Affiliation(s)
- Michal Schwartz
- Department of Neurobiology, The Weizmann Institute of Science, Rehovot, Israel.
| | | |
Collapse
|
32
|
Ibarra A, Hauben E, Butovsky O, Schwartz M. The therapeutic window after spinal cord injury can accommodate T cell-based vaccination and methylprednisolone in rats. Eur J Neurosci 2004; 19:2984-90. [PMID: 15182305 DOI: 10.1111/j.0953-816x.2004.03402.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Immune system activity has traditionally been considered harmful for recovery after spinal cord injury (SCI). Recent evidence suggests, however, that immune activity--and specifically autoimmune activity--is evoked by the insult, is beneficial if properly regulated and is amenable to boosting. Thus, for example, vaccination with an altered peptide ligand derived from myelin basic protein reduces the progressive degeneration of neurons that escaped the initial insult, thereby promoting recovery after SCI. As the steroid drug methylprednisolone (MP) is currently the only treatment available for patients with SCI, our purpose in the present study was to examine the mutual compatibility of the two treatments within the post-traumatic therapeutic window. We show, using rats of two different strains, that if MP is injected concomitantly with the therapeutic vaccination, the beneficial effect of the vaccination is diminished. However, if MP is given immediately after the insult and the vaccination 48 h later, MP does not detract from the beneficial effect of the vaccination. These results demonstrate that the therapeutic window after SCI can accommodate immediate administration of MP plus a delayed therapeutic vaccination.
Collapse
Affiliation(s)
- Antonio Ibarra
- Department of Neurobiology, The Weizmann Institute of Science, 76100 Rehovot, Israel.
| | | | | | | |
Collapse
|
33
|
Nevo U, Golding I, Neumann AUAU, Schwartz M, Akselrod S. Autoimmunity as an immune defense against degenerative processes: a primary mathematical model illustrating the bright side of autoimmunity. J Theor Biol 2004; 227:583-92. [PMID: 15038992 DOI: 10.1016/j.jtbi.2003.11.031] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2003] [Revised: 11/17/2003] [Accepted: 11/26/2003] [Indexed: 11/21/2022]
Abstract
Self-tolerance, or the ability of the immune system to refrain from destroying the organism's own tissues, is a prerequisite for proper immune system operation. How such self-tolerance is achieved is still a subject of debate. The belief that autoimmunity poses a continuous threat to the organism was challenged by data demonstrating that autoimmunity has a protective function after traumatic injury to the central nervous system. This finding led us to suggest the 'comprehensive immunity' approach by which autoimmunity is viewed as a special case of immunity, namely as a defense mechanism that operates by fighting against the threat of potential destructive activity originated or mediated within the organism, similarly to the immune defense that operates against the threat from exogenous pathogens. We present a primary mathematical spatio-temporal model that supports this concept. The numerical solutions of this model illustrate the beneficial operation of a well-controlled immune response specific to self-antigens residing in the site of lesion. The model also explains how the response to self might be tolerated on a day-to-day basis. In addition, we demonstrate that the same autoimmune response, operating at different levels of regulation, can lead to either an autoimmune disease or a degenerative disorder. This preliminary qualitative model supports our contention that the way autoimmunity is perceived should be revised.
Collapse
Affiliation(s)
- Uri Nevo
- Abramson Center for Medical Physics, School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv, Israel
| | | | | | | | | |
Collapse
|
34
|
Schwartz M. Vaccination for glaucoma: dream or reality? Brain Res Bull 2004; 62:481-4. [PMID: 15036561 DOI: 10.1016/s0361-9230(03)00073-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2003] [Accepted: 02/17/2003] [Indexed: 11/20/2022]
Abstract
Glaucoma is a neurodegenerative disease of the optic nerve, which continues to progress even if the primary cause of degeneration is identified and alleviated. At any given time the affected optic nerve contains fibers that are amenable to neuroprotection, and will escape degeneration provided that the proper pharmacological or other intervention is applied. Autoimmunity has long been viewed as a deleterious phenomenon that should be terminated or at least minimized in order to preserve health. We recently demonstrated, however, that T cells specific to self-proteins residing in the site of CNS insult can be protective. With the aim of boosting autoimmunity for neuroprotection without risking the induction of an autoimmune disease, we developed the use of Cop-1 (an FDA-approved drug for the treatment of multiple sclerosis) as an active vaccination for neuroprotection. Cop-1 is a synthetic polymer that weakly cross-reacts with a wide range of self-reacting T cells. Vaccination with Cop-1 resulted in significant neuroprotection in rat models of optic nerve crush and chronic glaucoma. Thus, boosting of a T cell-based mechanism, which we have termed 'protective autoimmunity', promotes recovery of the damaged optic nerve. Current studies in our laboratory are aimed at translating this treatment into a clinical therapy.
Collapse
Affiliation(s)
- Michal Schwartz
- Department of Neurobiology, The Weizmann Institute of Science, 76100 Rehovot, Israel
| |
Collapse
|
35
|
Kipnis J, Avidan H, Markovich Y, Mizrahi T, Hauben E, Prigozhina TB, Slavin S, Schwartz M. Low-dose gamma-irradiation promotes survival of injured neurons in the central nervous system via homeostasis-driven proliferation of T cells. Eur J Neurosci 2004; 19:1191-8. [PMID: 15016077 DOI: 10.1111/j.1460-9568.2004.03207.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Protective autoimmunity was only recently recognized as a mechanism for attenuating the progression of neurodegeneration. Using a rat model of optic nerve crush or contusive spinal cord injury, and a mouse model of neurodegenerative conditions caused by injection of a toxic dose of intraocular glutamate, we show that a single low dose of whole-body or lymphoid-organ gamma-irradiation significantly improved the spontaneous recovery. Animals with severe immune deficiency or deprived of mature T cells were unable to benefit from this treatment, suggesting that the irradiation-induced neuroprotection is immune mediated. This suggestion received further support from the findings that irradiation was accompanied by an increased incidence of activated T cells in the lymphoid organs and peripheral blood and an increase in mRNA encoding for the pro-inflammatory cytokines interleukin-12 and interferon-gamma, and that after irradiation, passive transfer of a subpopulation of suppressive T cells (naturally occurring regulatory CD4(+)CD25(+) T cells) wiped out the irradiation-induced protection. These results suggest that homeostasis-driven proliferation of T cells, induced by a single low-dose irradiation, leads to boosting of T cell-mediated neuroprotection and can be utilized clinically to fight off neurodegeneration and the threat of other diseases in which defense against toxic self-compounds is needed.
Collapse
Affiliation(s)
- Jonathan Kipnis
- Department of Neurobiology, The Weizmann Institute of Science, Rehovot, Israel
| | | | | | | | | | | | | | | |
Collapse
|
36
|
Shaked I, Porat Z, Gersner R, Kipnis J, Schwartz M. Early activation of microglia as antigen-presenting cells correlates with T cell-mediated protection and repair of the injured central nervous system. J Neuroimmunol 2004; 146:84-93. [PMID: 14698850 DOI: 10.1016/j.jneuroim.2003.10.049] [Citation(s) in RCA: 115] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
After an injury to the central nervous system (CNS), activated microglia have been shown to contribute to the ongoing destructive processes leading to secondary neuronal degeneration. They can, however, also express neuroprotective activity. Studies from our laboratory point to the existence of a physiological T cell-mediated neuroprotective mechanism (adaptive immunity) that is amenable to boosting. We postulate that the beneficial or destructive outcome of the local microglial (innate) response is determined by a well-controlled dialog between the innate and the adaptive immune players. Here, we show that spontaneous or exogenously boosted T cell-mediated neuroprotection is correlated with early activation of microglia as antigen-presenting cells. We suggest that such microglial activity, if well controlled, is a crucial step in determining the fate of the neurons in a hostile environment.
Collapse
Affiliation(s)
- Iftach Shaked
- Department of Neurobiology, The Weizmann Institute of Science, 76100 Rehovot, Israel
| | | | | | | | | |
Collapse
|
37
|
Schwartz M. Protective autoimmunity and prospects for therapeutic vaccination against self-perpetuating neurodegeneration. ERNST SCHERING RESEARCH FOUNDATION WORKSHOP 2004:133-54. [PMID: 15032058 DOI: 10.1007/978-3-662-05426-0_8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- M Schwartz
- Department of Neurobiology, Weizmann Institute of Science, 76100 Rehovot, Israel.
| |
Collapse
|
38
|
Vaccination with dendritic cells pulsed with peptides of myelin basic protein promotes functional recovery from spinal cord injury. J Neurosci 2003. [PMID: 14507981 DOI: 10.1523/jneurosci.23-25-08808.2003] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Injury-induced self-destructive processes cause significant functional loss after incomplete spinal cord injury (SCI). Cellular elements of both the innate (macrophage) and the adaptive (T-cell) immune response can, if properly activated and controlled, promote post-traumatic regrowth and protection after SCI. Dendritic cells (DCs) trigger activation of effector and regulatory T-cells, providing a link between the functions of the innate and the adaptive immune systems. They also initiate and control the body's response to pathogenic agents and regulate immune responses to both foreign and self-antigens. Here we show that post-injury injection of bone marrow-derived DCs pulsed with encephalitogenic or nonencephalitogenic peptides derived from myelin basic protein, when administered (either systemically or locally by injection into the lesion site) up to 12 d after the injury, led to significant and pronounced recovery from severe incomplete SCI. No significant protection was seen in DC recipients deprived of mature T-cells. Flow cytometry, RT-PCR, and proliferation assays indicated that the DCs prepared and used here were mature and immunogenic. Taken together, the results suggest that the DC-mediated neuroprotection was achieved via the induction of a systemic T-cell-dependent immune response. Better preservation of neural tissue and diminished formation of cysts and scar tissue accompanied the improved functional recovery in DC-treated rats. The use of antigen-specific DCs may represent an effective way to obtain, via transient induction of an autoimmune response, the maximal benefit of immune-mediated repair and maintenance as well as protection against self-destructive compounds.
Collapse
|
39
|
Monsonego A, Beserman ZP, Kipnis J, Yoles E, Weiner HL, Schwartz M. Beneficial effect of orally administered myelin basic protein in EAE-susceptible Lewis rats in a model of acute CNS degeneration. J Autoimmun 2003; 21:131-8. [PMID: 12935782 DOI: 10.1016/s0896-8411(03)00091-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Axonal injury in the central nervous system (CNS) results in the degeneration of directly damaged fibers and also in the secondary degeneration of fibers that escaped the primary insult. Studies have shown that a protective T cell-mediated autoimmunity directed against myelin-related self-antigens is a physiological response to CNS insult, spontaneously elicited in strains that are constitutionally resistant to experimental autoimmune encephalomyelitis (EAE) but not in EAE-susceptible strains. The protective response following axonal injury can be induced in susceptible rats and boosted in resistant rats by passive or active immunization with myelin-related antigens. Here we show that oral administration of low-dose myelin basic protein (MBP) over a 5-day period is beneficial for post-traumatic survival of neurons in Lewis (EAE-susceptible) rats. Protection was accompanied by increased expression of the costimulatory molecule B7.2 in the traumatized nerves, similar to that seen after passive transfer of MBP-specific T cells. These results support the contention that properly controlled autoimmunity is the body's defense mechanism against non-infective insults. Oral immunization with MBP can be viewed as a way to control the autoimmunity capable of fighting off the consequences of CNS injury in EAE-susceptible strains.
Collapse
Affiliation(s)
- Alon Monsonego
- Department of Neurobiology, The Weizmann Institute of Science, 76100 Rehovot, Israel
| | | | | | | | | | | |
Collapse
|
40
|
Kipnis J, Nevo U, Panikashvili D, Alexandrovich A, Yoles E, Akselrod S, Shohami E, Schwartz M. Therapeutic vaccination for closed head injury. J Neurotrauma 2003; 20:559-69. [PMID: 12906740 DOI: 10.1089/089771503767168483] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Closed head injury often has a devastating outcome, partly because the insult, like other injuries to the central nervous system (CNS), triggers self-destructive processes. During studies of the response to other CNS insults, it was unexpectedly discovered that the immune system, if well controlled, provides protection against self-destructive activities. Here we show that in mice with closed head injury, the immune system plays a key role in the spontaneous recovery. Strain-related differences were observed in the ability to harness a T cell-dependent protective mechanism against the effects of the injury. We further show that the trauma-induced deficit could be reduced, both functionally and anatomically, by post-traumatic vaccination with Cop-1, a synthetic copolymer used to treat patients with multiple sclerosis and found (using a different treatment protocol) to effectively counteract the loss of neurons caused by axonal injury or glutamate-induced toxicity. We suggest that a compound such as Cop-1 can be safely developed as a therapeutic vaccine to boost the body's immune repair mechanisms, thereby providing multifactorial protection against the consequences of brain trauma.
Collapse
Affiliation(s)
- Jonathan Kipnis
- Department of Neurobiology, The Weizmann Institute of Science, Rehovot, Israel
| | | | | | | | | | | | | | | |
Collapse
|
41
|
Angelov DN, Waibel S, Guntinas-Lichius O, Lenzen M, Neiss WF, Tomov TL, Yoles E, Kipnis J, Schori H, Reuter A, Ludolph A, Schwartz M. Therapeutic vaccine for acute and chronic motor neuron diseases: implications for amyotrophic lateral sclerosis. Proc Natl Acad Sci U S A 2003; 100:4790-5. [PMID: 12668759 PMCID: PMC153634 DOI: 10.1073/pnas.0530191100] [Citation(s) in RCA: 142] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Therapeutic vaccination with Copaxone (glatiramer acetate, Cop-1) protects motor neurons against acute and chronic degenerative conditions. In acute degeneration after facial nerve axotomy, the number of surviving motor neurons was almost two times higher in Cop-1-vaccinated mice than in nonvaccinated mice, or in mice injected with PBS emulsified in complete Freund's adjuvant (P < 0.05). In mice that express the mutant human gene Cu/Zn superoxide dismutase G93A (SOD1), and therefore simulate the chronic human motor neuron disease amyotrophic lateral sclerosis, Cop-1 vaccination prolonged life span compared to untreated matched controls, from 211 +/- 7 days (n = 15) to 263 +/- 8 days (n = 14; P < 0.0001). Our studies show that vaccination significantly improved motor activity. In line with the experimentally based concept of protective autoimmunity, these findings suggest that Cop-1 vaccination boosts the local immune response needed to combat destructive self-compounds associated with motor neuron death. Its differential action in CNS autoimmune diseases and neurodegenerative disorders, depending on the regimen used, allows its use as a therapy for either condition. Daily administration of Cop-1 is an approved treatment for multiple sclerosis. The protocol for non-autoimmune neurodegenerative diseases such as amyotrophic lateral sclerosis, remains to be established by future studies.
Collapse
Affiliation(s)
- D N Angelov
- Department of Oto-Rhino-Laryngology, University of Cologne, D50924 Cologne, Germany
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
42
|
Abstract
Inflammation has been widely perceived as participating in the etiology of acute and chronic neurodegenerative conditions. Accordingly, in the context of traumatic injuries or chronic neurodegenerative diseases in the central nervous system (CNS), activated microglia have been viewed as detrimental and attempts have been made to treat both conditions by antiinflammatory therapy. Recent studies have suggested that microglia act as stand- by cells in the service of both the immune and the nervous systems. In the healthy CNS these cells are quiescent, but in the event of injury to axons or cell bodies they exercise their neural function by buffering harmful self-compounds and clearing debris from the damaged site, and their immune function by providing immune-related requirements for recovery. Proper regulation of the inflammatory (autoimmune) response to injury will arrest degeneration and promote regrowth, whereas inappropriate regulation will lead to ongoing degeneration. Regulation is achieved by the operation of a T cell-mediated response directed to abundant self-antigens residing in the damaged site. Since this immune-dependent mechanism was found to protect against glutamate toxicity (a major factor in neurodegenerative disorders), boosting of this response might constitute the basis for development of a therapeutic vaccination against neurodegenerative diseases, all of which exhibit similar pathways and patterns of progression.
Collapse
Affiliation(s)
- Michal Schwartz
- Department of Neurobiology, The Weizmann Institute of Science, Rehovot, Israel.
| |
Collapse
|
43
|
Schwartz M. Neuroprotection as a treatment for glaucoma: pharmacological and immunological approaches. Eur J Ophthalmol 2003; 13 Suppl 3:S27-31. [PMID: 12749674 DOI: 10.1177/112067210301303s05] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Primary open-angle glaucoma is a chronic, progressive optic neuropathy associated with a gradual decline in visual function, which may lead to blindness. In most cases, the optic neuropathy is associated with increased intraocular pressure. It is now generally accepted, however, that normalization of pressure, although necessary, is often not-sufficient as a remedial measure. This is because of the existence of additional factors, some of which emerge as a consequence of the initial damage. This situation is reminiscent of the response to a traumatic axonal insult, in which some of the damage is immediate and is caused by the insult itself, and some is secondary and is caused by a deficiency of growth-supportive factors as well as by toxic factors derived from the damaged tissue. Accordingly, the author has suggested that glaucoma may be viewed as a neurodegenerative disease and consequently amenable to any therapeutic intervention applicable to neurodegenerative diseases. There is evidence that neuroprotection can be achieved both pharmacologically and immunologically. Pharmacologic intervention neutralizes some of the effects of the nerve-derived toxic factors and possibly increases the ability of the remaining healthy neurons, at any given time, to cope with the stressful conditions. Immunologic intervention boosts the body's repair mechanisms for counteracting the toxicity of physiologic compounds acting as stress signals.
Collapse
Affiliation(s)
- M Schwartz
- Department of Neurobiology, The Weizmann Institute of Science, Rehovot, Israel.
| |
Collapse
|
44
|
Nevo U, Kipnis J, Golding I, Shaked I, Neumann A, Akselrod S, Schwartz M. Autoimmunity as a special case of immunity: removing threats from within. Trends Mol Med 2003; 9:88-93. [PMID: 12657429 DOI: 10.1016/s1471-4914(03)00024-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The function of the adaptive immune response against exogenous (non-self) agents is to help the innate arm of the immune system (represented by phagocytic cells) to fight and eliminate these agents. We suggest that the body also protects itself against potentially harmful self components using mechanisms similar to those used for fighting and eliminating non-self agents, and that the protective immune activity against self-components competes with the activity of self-destructive compounds. Tolerance to self is thus not a lack of response to self, but the ability to tolerate an active defense response to self without developing an autoimmune disease.
Collapse
Affiliation(s)
- Uri Nevo
- School of Physics and Astronomy, Tel Aviv University, 69978 Tel Aviv, Israel
| | | | | | | | | | | | | |
Collapse
|
45
|
Hauben E, Schwartz M. Therapeutic vaccination for spinal cord injury: helping the body to cure itself. Trends Pharmacol Sci 2003; 24:7-12. [PMID: 12498724 DOI: 10.1016/s0165-6147(02)00013-5] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Inflammation is thought to exacerbate the outcome of spinal cord injury. However, our findings have led us to view inflammation as a healing response that needs the help of a systemic immune response mediated by T helper 1 (Th1) cells that are specific to the abundant antigens residing in the lesion site. Strains differ in their ability to manifest, at the right time and intensity, a spontaneous T-cell response to antigens at the lesion site and therefore in their ability to generate a local inflammatory response whose outcome is beneficial (maintenance and repair). All strains, however, can benefit from immune intervention that boosts and regulates the inflammatory response. Because recovery comprises multi-step processes, pharmacological intervention will be less effective than well-synchronized, self-healing immune activity. Risk-free neuroprotective intervention might be achieved by post-traumatic vaccination with a weak, non-pathogenic, auto-antigen, causing autoimmune T cells to home to the lesion site where they become activated and therefore activate local phagocytic cells to remove hostile elements and provide growth factors.
Collapse
Affiliation(s)
- Ehud Hauben
- Department of Neurobiology, The Weizmann Institute of Science, 76100, Rehovot, Israel
| | | |
Collapse
|
46
|
Schwartz M. Autoimmunity as the body's defense mechanism against the enemy within: Development of therapeutic vaccines for neurodegenerative disorders. J Neurovirol 2002; 8:480-5. [PMID: 12476343 DOI: 10.1080/13550280290101012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Insults to the central nervous system (CNS), whether of microbial or microbe-free origin, result in tissue damage. Until recently, it was generally believed that only microbe-related damage elicits an adaptive immune response, the purpose of which is to eliminate the offending microorganisms. Recent studies in the author's laboratory suggest, however, that the body exhibits an adaptive immune response to microbe-free injuries as well. The immune response in this case is directed against dominant self-antigens residing in the damaged site, where such an adaptive anti-self immune response reinforces the protective activity of local resident cells by providing them with factors that can augment and regulate their capacity for buffering troublemakers such as destructive self-compounds emerging from the injured neural tissue. Because the specificity of this autoimmune response apparently depends not on the type but on the site of lesion, the response can be boosted by therapeutic vaccination for acute and chronic neurodegenerative conditions irrespective of their primary etiology. The results have far-reaching implications, both for microbial infections and for neurodegenerative diseases of the CNS.
Collapse
Affiliation(s)
- Michal Schwartz
- Department of Neurobiology, The Weizmann Institute of Science, Rehovot, Israel
| |
Collapse
|