myelin-basic-protein and Uveitis

To investigate the antigenic specificity of the immune neuroprotective mechanism that can protect retinal ganglion cells (RGCs) against death caused by high intraocular pressure (IOP).. A unilateral increase in IOP was induced in rats by argon laser photocoagulation of the episcleral veins and limbal plexus. Rats with high IOP were immunized with glatiramer acetate (Cop-1, a synthetic copolymer) or with myelin-derived or uveitogenic peptides. When the steroid drug methylprednisolone was used, it was administered intraperitoneally every other day for 12 days.. Vaccination with myelin-derived peptides that reside in the axons failed to protect RGCs from death caused by high IOP. In contrast, IOP-induced RGC loss was reduced by vaccination with R16, a peptide derived from interphotoreceptor retinoid-binding protein, an immunodominant antigen residing in the eye. The benefit of protection against IOP-induced RGC loss outweighed the cost of the monophasic experimental autoimmune uveitis (EAU) that transiently developed in a susceptible rat strain. Treatment with methylprednisolone alleviated the disease symptoms, but caused further loss of RGCs. Cop-1 vaccination was effective in both EAU-resistant and EAU-susceptible strains.. To benefit damaged neurons, immune neuroprotection should be directed against immunodominant antigens that reside in the site of damage. In a rat model of high IOP, RGCs can benefit from vaccination with peptides derived from proteins that are immunodominant in the eye but not from myelin-associated proteins. This suggests that the site of primary degeneration in IOP-induced RGC loss is in the eye. Cop-1 vaccination apparently circumvents the site-specificity barrier and provides protection without risk of inducing autoimmune disease.

Topics: Animals; Autoimmune Diseases; Cell Survival; Cytoprotection; Disease Models, Animal; Eye Proteins; Glaucoma; Immunodominant Epitopes; Intraocular Pressure; Male; Methylprednisolone; Myelin Basic Protein; Ocular Hypertension; Oligopeptides; Rats; Rats, Inbred Lew; Rats, Sprague-Dawley; Retinal Ganglion Cells; Retinol-Binding Proteins; Uveitis; Vaccination; Vaccines, Synthetic

To investigate the site and the cellular source of inducible nitric oxide synthase (iNOS) expression in human S-antigen peptide-induced experimental autoimmune uveoretinitis (EAU).. Twenty-one Lewis rats were sensitized with human S-antigen peptides. Three rats were killed each consecutive day from day 6 through day 12 after sensitization. Frozen sections of the enucleated eyes were analyzed for iNOS by the dual immunohistochemical method. Primary antibodies included rabbit anti-mouse iNOS combined with anti-human endothelium NOS, anti-rat lysosomal protein (ED1), or anti-rat major histocompatibility complex class II molecule (OX6) monoclonal antibodies. Secondary antibodies were fluorescein-conjugated anti-mouse IgG and streptavidin rhodamine-labeled anti-rabbit IgG. The adjacent sections were separately stained with ED1, iNOS, and glial fibrillary acidic protein (GFAP). The mouse macrophage cell line RAW 264.7 was exposed to either interferon (IFN)gamma/lipopolysaccharide (LPS) or S-antigen and to interphotoreceptor retinoid-binding protein (IRBP), myelin basic protein, and bovine serum albumin for 12 hours. Cells were harvested for detection of iNOS expression by northern blot analysis hybridization and detection of protein by immunohistochemistry.. In the retina of eyes with EAU, ED1+/iNOS+ and OX6+/iNOS+ cells were first detected on day 9 after sensitization. These iNOS+ cells increased in number on subsequent days in parallel with the increasing severity of retinal damage. Most of the cells localized around the outer retina. In contrast, a large number of ED1+ and OX6+ cells that were localized in the uvea and conjunctiva were negative for iNOS. Retinal pigment epithelial cells did not stain for iNOS. Macrophages exposed to IFNgamma/LPS, S-antigen, and IRBP showed expression of iNOS mRNA and the protein.. Macrophages are an important source of NO production in eyes with EAU. These macrophages preferentially express iNOS in the retina. Such a differential expression of iNOS by the macrophages appears to be related to retinal soluble proteins.

Topics: Animals; Arrestin; Blotting, Northern; Cattle; Cells, Cultured; Eye Proteins; Fluorescent Antibody Technique, Indirect; Humans; Macrophages; Mice; Myelin Basic Protein; Nitric Oxide; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Rabbits; Rats; Rats, Inbred Lew; Retinitis; Retinol-Binding Proteins; RNA, Messenger; Serum Albumin, Bovine; Uveitis

The adoptive transfer of autoreactive S100 beta-specific T cells induces experimental autoimmune panencephalomyelitis and uveoretinitis in the Lewis rat, mimicking the distribution of lesions seen in a subset of patients with multiple sclerosis. We studied the frequency and functional properties of the human T-cell response to S100 beta in eight patients (two relapsing-remitting multiple sclerosis, one chronic-progressive multiple sclerosis, two with multiple sclerosis and uveitis, two neuromyelitis optica, one panuveitis) and in seven healthy individuals, using bovine S100 beta for T-cell stimulation. Both in patients and controls, the frequency of S100 beta-specific T-cell responses was half of that obtained for myelin basic protein (MBP), and only 10% of that obtained using purified protein derivative (PPD). The stimulation indices obtained in response to S100 beta were also less than half those obtained with either MBP or PPD. However, four long-term S100 beta-specific T-cell lines were established and studied in more detail. The four T-cell lines all exhibited a CD4+, CD8-, T-cell receptor alpha beta + surface phenotype and secreted tumour necrosis factor-alpha, interferon-gamma, interleukin-10 and interleukin-4 upon antigenic stimulation, but they were heterogenous with respect to T-cell receptor usage; two T-cell lines expressed V beta 2, one V beta 6.7 and one V beta 13. Antigen-specificity was confirmed using bovine S100 beta beta and alpha beta-isoforms, as well as a recombinant rat S100 beta preparation. The response to S100 beta was shown to the HLA-(human leukocyte antigen-) DR-restricted for two of the S100 beta-specific T-cell lines. Human S100 beta-specific T-cell lines were cytotoxic, although to a lesser extent than MBP-specific T-cell lines derived from the same donors. The phenotypic and functional properties of human S100 beta-specific T-cell lines raise the possibility that these T cells are pathogenic, as they are in the rat. The low frequency and proliferative index of S100 beta-specific, as opposed to MBP-specific T-cell responses suggests that the T-cell response to this widely expressed calcium-binding protein is under more efficient regulatory control.

Topics: Adult; Animals; Antibody Specificity; Autoantigens; Calcium-Binding Proteins; Cattle; Cell Line; Cytokines; Cytotoxicity Tests, Immunologic; Demyelinating Diseases; Disease Models, Animal; Encephalomyelitis, Autoimmune, Experimental; Female; Histocompatibility Antigens; Histocompatibility Testing; Humans; Immunophenotyping; Immunotherapy, Adoptive; Male; Middle Aged; Multiple Sclerosis; Myelin Basic Protein; Nerve Growth Factors; Rats; Rats, Inbred Lew; Receptors, Antigen, T-Cell; S100 Calcium Binding Protein beta Subunit; S100 Proteins; T-Lymphocytes; Tuberculin; Uveitis

Uveitis of unknown etiology is known to occur in association with various systemic disorders. We now report that anterior uveitis (AU) can be produced by T cell immunity to myelin basic protein (BP) and accompanies experimental autoimmune encephalomyelitis (EAE). EAE with AU was induced in Lewis rats by immunization to BP in CFA or by immunization to various BP peptides including the encephalitogenic 71-90 peptide. Slit-lamp biomicroscopy of BP-immunized Lewis rats revealed AU, characterised by inflammation of the iris, in 73% of the eyes. The onset of AU in actively immunized rats varied between days 12 and 26, often appearing after spontaneous remission of the paralysis, the hallmark of EAE. The course of AU was progressive, affecting more than 50% of the surface of the iris in 16 of 29 diseased eyes. Like the paralysis, the AU was self-limiting: within 2 weeks the disease remitted. In addition, AU could be adoptively transferred to naive and irradiated rats by a T cell clone specific for BP peptide 71-90. The present observations are compatible with the idea that AU may be triggered by BP-reactive T cells. The myelinated nerves present in the iris have been shown to contain BP. However, these peripheral nerves would now appear to be the only peripheral nerves susceptible to acute EAE.

Topics: Amino Acid Sequence; Animals; Aqueous Humor; Blood-Brain Barrier; Epitopes; Female; Molecular Sequence Data; Myelin Basic Protein; Rats; Rats, Inbred F344; Rats, Inbred Lew; T-Lymphocytes; Uveitis

Experimental autoimmune uveitis (EAU) serves as an animal model of ocular inflammation. The disease is caused by the immunization of microgram amounts of a soluble retinal protein, designated S-antigen, in susceptible animal strains, including primates. We induced EAU and experimental autoimmune pinealitis (EAP) in Lewis rats with a small synthetic peptide corresponding to amino acid positions 106-121 in yeast histone H3. This peptide contains five consecutive amino acids identical to a uveitopathogenic site (peptide M) in human S-antigen. Lymph node or mononuclear cells from different species of animals immunized either with histone H3 or with peptide M showed significant cross-reaction as measured by in vitro lymphocyte mitogenesis assay using [3H]thymidine. Also, we adoptively transferred the EAU and EAP in naive rats by immune lymph node cells. These findings support the fact that selected bacterial, viral, or fungal proteins with amino acid sequence homologies to normal retinal proteins are uveitopathogenic and, as such, provide a basis for autoimmune inflammatory diseases.

Topics: Amino Acid Sequence; Animals; Antigens; Autoimmune Diseases; Cross Reactions; Eye Proteins; Guinea Pigs; Histones; Immunization, Passive; Lymphocyte Activation; Macaca; Myelin Basic Protein; Peptide Fragments; Pineal Gland; Rats; Rats, Inbred Lew; Sequence Homology, Nucleic Acid; T-Lymphocytes; Uveitis

Rat lymphocyte lines were established, with specificity toward two synthetic peptides derived from the interphotoreceptor retinoid-binding protein (IRBP), which specifically localizes in the retina and pineal gland. One of the peptides, R4, is immunopathogenic, producing experimental autoimmune uveoretinitis (EAU) and pinealitis (EAP) in immunized rats, while the other peptide, R3, exhibits no detectable immunopathogenicity in rats. The cell lines carry surface markers specific for the helper/inducer subset of T-lymphocytes. When tested by the proliferation assay, the line cells demonstrated major histocompatibility-restricted vigorous responses against the immunizing (homologous) peptide, but failed to recognize the intact IRBP molecule. This finding is in line with other data indicating that peptides R3 and R4 are nonimmunodominant determinants of IRBP for the Lewis rat. Yet, the cell lines specific for R4 were highly immunopathogenic, producing EAU and EAP in naive rats at numbers as low as 0.25 x 10(6), with histopathological changes similar to those induced by active immunization with this peptide. The immunological capacity of the cell lines was further demonstrated by the finding that spleen cells from recipient rats of these lines responded well against the homologous peptides. The uniqueness of this system, in which lymphocytes specific toward a nondominant determinant are immunopathogenic, is underscored and the possible mechanisms of disease induction are discussed.

Topics: Animals; Autoimmune Diseases; Brain Diseases; Cell Line; Eye Proteins; Inflammation; Lymphocyte Activation; Male; Myelin Basic Protein; Pineal Gland; Rats; Rats, Inbred Lew; Retinitis; Retinol-Binding Proteins; T-Lymphocytes; Uveitis

An immunological basis for neurological involvement in Vogt-Koyanagi-Harada syndrome was sought by means of the migration-inhibition factor technique with human myelin basic protein. The test was carried out in four patients who had recent manifestations of the syndrome, two of whom were evaluated both before and after initiation of steroid treatment; in one patient 4 years after recovery from the syndrome; in three patients having uveitis of other causes, and in 12 healthy controls. The results were positive in all four patients who had recent manifestations, whereas they were negative in all the others. This finding may constitute evidence of a cell-mediated immunity toward components of the nervous system in this disease entity.

Topics: Antigens; Cell Migration Inhibition; Humans; Immunity, Cellular; Myelin Basic Protein; Uveitis; Uveomeningoencephalitic Syndrome