It is well documented that serum IgG from rheumatoid arthritis (RA) patients exhibits decreased galactosylation of its conservative N-glycans (Asn-297) in CH2 domains of the heavy chains; it has been shown that this agalactosylation is proportional to disease severity. In the present investigation we analyzed galactosylation of IgG derived from the patients using a modified ELISA-plate test, biosensor BIAcore and total sugar analysis (GC-MS). For ELISA and BIAcore the binding of IgG preparations, purified from the patients' sera, to two lectins: Ricinus communis (RCA-I) and Griffonia simplicifolia (GSL-II) was applied. Based on ELISA-plate test an agalactosylation factor (AF, a relative ratio of GSL-II/RCA-I binding) was calculated, which was proportional to actual disease severity. Repeated testing of several patients before and after treatment with methotrexate (MTX) alone or in combination with Remicade (a chimeric antibody anti-TNF-alpha) supplied results indicating an increase of IgG galactosylation during the treatment. This introductory observation suggests that IgG galactosylation may be an additional indicator of the RA patients' improvement.

Multiple sclerosis (MS) is the most common demyelinating and an autoimmune disease of the central nervous system characterized by immune-mediated myelin and axonal damage, and chronic axonal loss attributable to the absence of myelin sheaths. T cell subsets (Th1, Th2, Th17, CD8+, NKT, CD4+CD25+ T regulatory cells) and B cells are involved in this disorder, thus new MS therapies seek damage prevention by resetting multiple components of the immune system. The currently approved therapies are immunoregulatory and reduce the number and rate of lesion formation but are only partially effective. This review summarizes current understanding of the processes at issue: myelination, demyelination and remyelination—with emphasis upon myelin composition/architecture and oligodendrocyte maturation and differentiation. The translational options target oligodendrocyte protection and myelin repair in animal models and assess their relevance in human. Remyelination may be enhanced by signals that promote myelin formation and repair. The crucial question of why remyelination fails is approached is several ways by examining the role in remyelination of available MS medications and avenues being actively pursued to promote remyelination including: (i) cytokine-based immune-intervention (targeting calpain inhibition), (ii) antigen-based immunomodulation (targeting glycolipid-reactive iNKT cells and sphingoid mediated inflammation) and (iii) recombinant monoclonal antibodies-induced remyelination.

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Myelin lipids have long been thought to play intriguing roles in the pathogenesis of multiple sclerosis (MS). This review summarizes current understanding of the molecular basis of MS with emphasis on the: (i.) physico-chemical properties, organization and accessibility of the lipids and their distribution within the myelin multilayer; (ii.) characterization of myelin lipid structures, and structure-function relationships relevant to MS mechanisms, and; (iii.) immunogenic and other features of lipids in MS including molecular mimicry, lipid enzyme genetic knockouts, glycolipid-reactive NKT cells, and monoclonal antibody-induced remyelination. New findings associate anti-lipid antibodies with pathophysiological biomarkers and suggest clinical utility. The structure of CD1d-lipid complexed with the lipophilic invariant T cell receptor (iTCR) may be crucial to understanding MS pathogenesis, and design of lipid antigen-specific therapeutics. Novel immuno-modulatory tools for treatment of autoimmune diseases including MS in which there is both constraint of inflammation and stimulation of remyelination are now emerging.

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We have found a series of myelin glycolipids that are derivatives of galactosylceramide (GalCer) with higher TLC-Rf, and we have designated them as fast migrating cerebrosides (FMC) ( 1 ). The simplest two compounds of this series (FMC-1 and FMC-2) are GalCer derivatives with 3-O-acetylation of the sphingosyl moiety that differ by incorporation of nonhydroxy and 2-hydroxy fatty-N -acylation, respectively ( 1 ). The next two (FMC-3 and FMC-4) are analogs of FMC-1 and FMC-2 with additional O-acetylation at the galactose C6 hydroxyl ( 2 ). Previously, we have examined these cerebroside (galactosylceramide) derivatives in rat, bovine, and human brain and found them present in all three species, varying in species from 15-35% of tissue galactosylceramide content ( 1 )

Activated microglia release pro-inflammatory factors and calpain into the extracellular milieu, damaging surrounding neurons. Mechanistic links to progressive neurodegeneration in diseases such as Parkinson’s disease (PD) and multiple sclerosis (MS) remain however obscure. We hypothesize that persistent damaged/dying neurons may also release cytotoxic factors and calpain into the media which then activate microglia again. Thus, inflammation, neuronal damage, and microglia activation, i.e. bi-directional interaction between neurons and microglia, may be involved in the progressive neurodegeneration. We tested this hypothesis using two in vitro models: (1) the effects of soluble factors from damaged primary cortical neurons upon primary rat neuron-microglia and (2) soluble factors released from CD3/CD28 activated peripheral blood mononuclear cells (PBMCs) of MS patients on primary human neurons and microglia. The first model indicated that neurons injured with pro-inflammatory agents (IFN-γ) release soluble neurotoxic factors, including Cox-2, ROS, and calpain, thus activating microglia, which in turn released neurotoxic factors as well. This repeated microglial activation leads to persistent inflammation and neurodegeneration. The released calpain from neurons and microglia was confirmed by calpain inhibitors calpeptin or SNJ-1945 as well as μ and mcalpain knock down using siRNA technology. Our second model using activated PBMCs, a source of pro-inflammatory Th1/Th17 cytokines and calpain released from auto-reactive T cells corroborated results in human primary cell cultures and confirmed calpain to be involved in progressive MS. These insights into reciprocal paracrine regulation of cell injury and calpain activation in the progressive phase of MS, PD, and other neurodegenerative diseases suggest potentially beneficial preventive and therapeutic strategies, including calpain inhibition

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