krn-7000 and Multiple-Sclerosis

T cells reactive to lipids and restricted by major histocompatibility complex (MHC) class I-like molecules represent more than 15% of all lymphocytes in human blood. This heterogeneous population of innate cells includes the invariant natural killer T cells (iNK T), type II NK T cells, CD1a,b,c-restricted T cells and mucosal-associated invariant T (MAIT) cells. These populations are implicated in cancer, infection and autoimmunity. In this review, we focus on the role of these cells in autoimmunity. We summarize data obtained in humans and preclinical models of autoimmune diseases such as primary biliary cirrhosis, type 1 diabetes, multiple sclerosis, systemic lupus erythematosus, rheumatoid arthritis, psoriasis and atherosclerosis. We also discuss the promise of NK T cell manipulations: restoration of function, specific activation, depletion and the relevance of these treatments to human autoimmune diseases.

Topics: Animals; Arthritis, Rheumatoid; Atherosclerosis; Autoimmunity; Clinical Trials, Phase I as Topic; Diabetes Mellitus, Type 1; Female; Galactosylceramides; Humans; Liver Cirrhosis, Biliary; Lupus Erythematosus, Systemic; Male; Mice; Multiple Sclerosis; Natural Killer T-Cells; Psoriasis

Here we briefly review our understanding of the immune response to myelin-derived glycolipids during an inflammatory autoimmune response in the central nervous system (CNS). We focus primarily on the recognition of the self-glycolipid sulfatide by a distinct population of non-invariant NK T cells. The results of studies we have obtained so far in investigating the presentation of sulfatide by CNS-resident cells including microglia and their interactions with T cells indicate that this pathway might be successfully targeted for the treatment of autoimmune demyelination in multiple sclerosis.

Topics: Animals; Antigens, CD1; Demyelinating Autoimmune Diseases, CNS; Encephalomyelitis, Autoimmune, Experimental; Galactosylceramides; Glycolipids; Humans; Killer Cells, Natural; Mice; Multiple Sclerosis; Sulfoglycosphingolipids; T-Lymphocytes

Our previous works indicate that regulatory cells such as natural killer (NK) cells and NKT cells could play an active role in maintaining the remission state of MS. We have therefore adopted a strategy for developing the future MS therapy by targeting NKT cells. The unique glycolipid-reactive lymphocytes are known to produce a large quantity of Th2 cytokines such as IL-4 when encountering their ligands like alpha-galactosylceramide (alpha-GC). Whereas most of the NKT ligands so far described would stimulate both Th1 and Th2 cytokine production by NKT cells, the synthetic compound OCH, an analogue of alpha-GC with a shorter lipid tail, is the one which selectively induces IL-4 production. Given this property, oral or intraperitoneal OCH administration would prohibit the development of a variety of Th1-meediated pathology, including EAE, collagen-induced arthritis, type 1 diabetes, DSS-induced colitis and acute GVHD by inducing Th2 bias. This review paper summarizes the recent publications and our unpublished results related to the efficacy of OCH and to the molecular mechanism accounting for the Th2 inducing property of OCH.

Topics: Animals; Disease Models, Animal; Galactosylceramides; Glycolipids; Immunotherapy; Interleukin-4; Mice; Multiple Sclerosis; T-Lymphocytes

Natural killer T (NKT) cells are a conserved subpopulation of lymphocytes that recognize glycolipid antigens in a CD1d context. Upon activation through their semi-invariant T cell receptor, these cells rapidly release large amounts of immunomodulating Th1 and Th2 cytokines. NKT cells have therefore been implicated in immune responses controlling various diseases, including infection, cancer, transplantation, and autoimmunity. Stimulation of the immunoregulatory capacity of NKT cells by the prototypical antigen alpha-galactosylceramide results in amelioration of disease in several animal models. This review will focus on the current knowledge of human NKT cells and their role in autoimmune diseases. The features of these cells and their importance in regulation of autoimmunity suggest that NKT cell-based therapies might be an interesting approach for the treatment of autoimmune diseases.

Topics: Animals; Autoimmune Diseases; Autoimmunity; Diabetes Mellitus, Type 1; Encephalomyelitis, Autoimmune, Experimental; Galactosylceramides; Humans; Killer Cells, Natural; Lymphocyte Activation; Multiple Sclerosis; T-Lymphocyte Subsets; T-Lymphocytes; Thymus Gland

CD1d-restricted Natural Killer T cells (NKT cells), a novel lymphocyte lineage, are considered to play an intermediary role bridging innate and acquired immunity. This review discusses the characteristics of NKT cells and their biological significance in the immune system, and summarizes their in vivo functions observed in a number of pathological settings, including infectious diseases, cancer, autoimmunity, and transplantation. Further, we discuss recent data that have generated considerable interest in utilizing NKT cells as targets of new therapeutic interventions in various human diseases.

Topics: Animals; Antigens, CD1; Antigens, CD1d; Apoptosis; Autoimmunity; Cell Transplantation; Cytokines; Diabetes Mellitus, Type 1; Encephalomyelitis, Autoimmune, Experimental; Galactosylceramides; Glycolipids; Humans; Immune System; Immunity, Innate; Killer Cells, Natural; Multiple Sclerosis; Neoplasms

Multiple sclerosis (MS) is an autoimmune disorder characterised by clinical relapse and remission and pathological demyelination with varying inflammation. Because it is suggested that T-cells expressing natural killer cell receptors (NKR) play important roles in regulating human autoimmune diseases, we have quantified populations of T-cells expressing the NKR CD56, CD161 and CD94 in the peripheral blood of MS patients, in healthy control subjects (HS) and in patients with other neurological diseases (OND). CD161(+) T-cells and CD94(+) T-cells were significantly decreased in MS patients with primary progressive disease and secondary progressive disease respectively whereas CD56(+) T-cell numbers were unchanged. In contrast NKT-cells that express the invariant Valpha24-Jalpha18(+) T-cell receptor identified here by specific receptor antibody and CD1d-tetrameric PBS57-loaded complexes, were increased in MS patients compared with HS. Reductions in CD161(+) T-cells and CD94(+) T-cells relative to HS were also observed in the OND group and this was particularly prominent in Parkinsonian patients. A striking functional finding was that while NKT-cells in unfractionated peripheral blood from healthy subjects expanded in number and produced IFN-gamma upon stimulation with alpha-galactosylceramide, NKT-cells from MS patients did not. Thus we have identified alterations in a number of potentially important lymphocyte sub-populations warranting further investigation in the immune response in MS.

Topics: Adult; Antigens, CD; Disease Progression; Female; Flow Cytometry; Galactosylceramides; Humans; Male; Middle Aged; Multiple Sclerosis; Natural Killer T-Cells; Nervous System Diseases; Receptors, Antigen, T-Cell; Receptors, Natural Killer Cell; Statistics, Nonparametric; Young Adult

According to the molecular mimicry theory, multiple sclerosis (MS) develops when the immune system mistakenly attacks a component of the myelin sheath that is structurally similar to a foreign epitope. The glycolipid galactocerebroside (GalC) is a major component of myelin. As lipids comprise between 70% and 85% of myelin, glycolipids should be investigated as candidate autoantigens in MS. GalC displays broad structural similarities to the Borrelia burgdorferi glycolipid antigen BbGL-2 and to the Sphingomonas antigen GalAGSL. In principle, therefore, these bacteria may induce an autoimmune attack on the myelin sheath. GalC is also structurally similar to natural killer T (NKT) cell ligand alpha-galactosylceramide (alpha-GalCer). Further studies must be performed to clarify the role of GalC in the activation of NKT cells and the development of MS.

Topics: Animals; Autoimmunity; Borrelia burgdorferi; Galactosylceramides; Glycolipids; Humans; Killer Cells, Natural; Ligands; Models, Biological; Models, Chemical; Models, Theoretical; Multiple Sclerosis; Myelin Sheath; Sphingomonas