Publications
Amelioration of experimental colitis by Copaxone is associated with class-II-restricted CD4 immune blocking.
Clin Immuno
Liver Unit, Hadassah University Hospital, Jerusalem, Israel.
Copaxone modifies TH1 immune response in multiple sclerosis. As Crohn's disease shares TH1 predominance, this study came to investigate the anti-inflammatory response of Copaxone in animal model of colitis. METHODS: Colitis was induced by intra-rectal instillation of TNBS in 2 animal groups; one of them was daily treated intraperitoneally by 300 mug Copaxone starting 48 h post-colitis induction. Both colitis groups were compared to naive group. Eight male C57Bl6 mice were used in each group. At day 12, distal colon was excised for standard scoring, splenocytes were isolated for FACS and serum cytokines were assessed. Splenocytes were in-vitro-stimulated with colitis protein extracts in the presence or absence of Copaxone. Lymphocytes were blocked by either MHC anti-class I or anti-class II antibodies prior to Copaxone administration. RESULTS: Copaxone markedly alleviated macro/microscopic colitis scoring as they decreased from 2.9 +/- 1.1/2.6 +/- 0.8 in colitis group to 1.7 +/- 1/1.5 +/- 0.5 in Copaxone-treated mice (P = 0.03/P = 0.008, respectively) compared to 0 +/- 0/1 +/- 0 in naives (P < 0.001/P < 0.01, respectively). CD4 subsets significantly decreased following Copaxone administration as compared to naive mice (P = 0.05). Although Copaxone-treated mice manifested a block of both serum TH1/TH2 responses, only interferon gamma secreting CD4 cells significantly decreased. NK cells tend to increase following colitis induction (P = 0.08), however, they significantly decreased in Copaxone-treated animals (P = 0.006). NK-T followed NK pattern. Using in vitro studies, Copaxone showed amelioration of T-cell proliferation that was significantly blocked when cells were pre-incubated with anti-MHC class II but not class I antibodies. CONCLUSIONS: Copaxone had class-II-restricted anti-inflammatory effect in our animal colitis model associated with CD4/NK/NKT/TH1/TH2 suppression.
Involvement of a tissue-specific autoantibody in skin disorders of murine systemic lupus erythematosus and autoinflammatory diseases.
: Proc Natl Acad Sci U S A.
Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA.jlstrom@fas.harvard.edu
Human systemic lupus erythematosus (SLE) and its murine model, MRL lpr/lpr mice, are well known to develop a wide range of symptoms, such as glomerulonephritis, dermatitis, and arthritis, as an immune-complex disease. However, the deposition of circulating immune complex does not fully explain the tissue specificity of disease. Tissue-specific autoantigens may also be involved in tissue inflammation. In this study, desmoglein 3 (Dsg3), a major component of epidermal desmosomes, was identified as a skin-specific autoantigen. Several murine models of skin inflammation were found to develop autoantibodies to Dsg3 tightly correlated with disease aggravation, especially in MRL lpr/lpr mice. Furthermore, SLE-prone skin disease-free FcgammaRIIb-deficient mice developed skin inflammation upon immunization with Dsg3. Taken together with histological studies, we concluded that skin-specific Dsg3 serves as an autoantigen in chronic skin inflammatory diseases accompanied by mast cell degranulation, including both murine SLE and other autoinflammatory diseases.
Promiscuous binding of synthetic copolymer 1 to purified HLA-DR molecules.
Proc Natl Acad Sci U S A. 2006 Feb 28;103(9):3292-7. Epub 2006 Feb 21.
Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA.
Copolymer 1 (Cop 1) is a random synthetic amino acid copolymer of L-alanine, L-glutamic acid, L-lysine, and L-tyrosine, effective both in suppression of experimental allergic encephalomyelitis and in the treatment of relapsing forms of multiple sclerosis. Cop 1 binds promiscuously and very efficiently to living APCs of various HLA haplotypes. In the present study, a substantial part of the whole mixture of random polypeptides that compose Cop 1 was shown to bind to purified human HLA-DR1, DR2, and DR4 with high affinity in a temperature- and time (and, in the case of DR4, pH)-dependent manner, and was competitively inhibited by DR-restricted peptides, but not by peptide derivatives that bind with low affinity. Bacterial superantigens inhibited Cop 1 binding only at very high concentrations. The formation of the Cop 1-DR1 complex was also shown by SDS-PAGE. These findings represent the first direct evidence for interactions of Cop 1 with purified DR molecules, and suggest that its effectiveness in experimental allergic encephalomyelitis and multiple sclerosis may be directly related to its binding in the groove of HLA-DR proteins.
Glatiramer in the treatment of multiple sclerosis.
Int J Nanomedicine
Department of Clinical Neurosciences, Brown Medical School, Rhode Island Hospital, Providence, RI 02905, USA. srizvi@lifespan.org
Multiple sclerosis (MS) is a disease of the central nervous system with both an inflammatory and degenerative component. The disease primarily affects young adults and results in significant physical and cognitive disability. Several disease-modifying agents are currently used in the management of multiple sclerosis. Glatiramer acetate (GA, Copaxone, co-polymer 1) is a disease-modifying agent approved for the treatment of relapsing remitting multiple sclerosis. Apart from its unique mode of action, there is evidence pointing toward a possible neuroprotective role. This review will critically discuss GA's potential mechanisms of action, the results of clinical tria
The immunomodulator glatiramer acetate augments the expression of neurotrophic factors in brains of experimental autoimmune encephalomyelitis mice.
: Proc Natl Acad Sci U S A.
Departments of Immunology and Veterinary Resources, The Weizmann Institute of Science, Rehovot 76100, Israel.
Neurotrophins (NTs) such as BDNF, NT-3, and NT-4 are important modulators of neuronal function and survival. Their expression in the CNS after various insults is thus of major therapeutic consequence. Glatiramer acetate [(GA) Copaxone], an approved drug for the treatment of multiple sclerosis, has been shown to induce Th2/3 cells that accumulate in the CNS, expressing in situ antiinflammatory cytokines and BDNF. In the present study, we investigated whether s.c. injections of GA, applied at various stages of experimental autoimmune encephalomyelitis, affect the expression of NTs, particularly BDNF, in the brain. In untreated experimental autoimmune encephalomyelitis mice, the expression of NTs was elevated shortly after disease appearance but subsequently declined below that of naive mice. In contrast, GA treatment led to sustained augmentation in the expression of BDNF, NT-3, and NT-4 in various brain regions as demonstrated by histological analysis of immunostained brain sections. GA treatment, even when started 45 days after disease induction, restored the impaired level of NTs to that of healthy mice. BDNF elevation after GA treatment was demonstrated on both protein and mRNA levels. Prominent staining was manifested not only by infiltrating GA-induced T cells, but also by CNS resident cells (neurons and astrocytes), indicative of a bystander therapeutic effect. Of importance, in GA-treated mice, intense BDNF expression was manifested by neuronal progenitors that migrated into lesions in injured regions. These results indicate that the immunomodulator GA exerts not only an antiinflammatory effect, but also enhances neuroprotection and regeneration of neural elements in the diseased brain.


