Autoimmune Processes in Multiple Sclerosis: Production of Harmful Catalytic Antibodies Associated with Significant Changes in the Hematopoietic Stem Cell Differentiation and Proliferation

Multiple sclerosis (MS) is a chronic demyelinating disease of the central nervous system. MS pathogenesis is not clear. Destruction of myelin by inflammation caused by autoimmune reactions has been proposed. Interestingly, healthy humans usually do not develop abzymes (Abzs). It was shown that DNase and MBP-hydrolyzing Abzs are easily detectable at the beginning of autoimmune diseases (ADs) including MS, when concentrations of antibodies to autoantigens are not yet significantly increased and correspond to levels in healthy donors. In addition, the relative enzymatic activity of antibodies from cerebrospinal fluid (CSF) is ~50-fold higher than that from the sera of the same MS patients. Experimental autoimmune encephalomyelitis (EAE) in C57BL/6 mice, a model mimicking relevant aspects of human MS was used. During development of spontaneous and MOG35-55-induced EAE in C57BL/6 mice, a specific reorganization of the immune system of mice was observed. It leads to a condition which was associated with the generation of catalytically active IgGs-hydrolyzing DNA, myelin basic protein (MBP), and MOG. Production of Abzs was associated with increased proteinuria, leading changes in differentiation of mice bone marrow hematopoietic stem cells (HSCs) and an increase in proliferation of lymphocytes in bone marrow, spleen, and thymus as well as a significant suppression of cell apoptosis in these organs. Treatment of control non-autoimmune CBA mice with MOG led to the different differentiation and proliferation of HSCs comparing with EAE C57BL/6 mice. The treatment of EAE mice with cuprizone inducing demyelination lead to a significant decrease in the size of the brain corpus callosum, but do not significantly change the differentiation profile of HSCs differentiation when compared with untreated mice. It indicates that cuprizone treatment is associated with demyelination, but not autoimmune reactivity. The possible differences in immune system reorganizations during preclinical phases of the disease, acute and late EAE, leading to production of different autoantibodies and Abzs as well other changes are discussed

Catalytic Antibodies in Norm and Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is known as a systemic polyethiologic diffuse autoimmune disease characterized by connective tissue disorganization and the paramount damage of skin and visceral capillaries. Usually, SLE symptoms include high fever, hair loss, mouth ulcers, chest pain, swollen lymph nodes, painful and swollen joints, increased fatigue, and appearance of red rash more often on the face. The exact reason of SLE appearance is not really clear. Detection of catalytic Abs (abzymes) was shown to be the earliest indicator of different AI disease development. Some abzymes are cytotoxic and can play a dangerous negative role in the pathogenesis of AI diseases. SLE is characterized by the appearance of abzymes with several different catalytic functions including hydrolysis of peptides and proteins, DNA, RNA, and oligosaccharides. In addition, monoclonal SLE abzymes are characterized by extraordinary diversity in the affinity to the substrates, physicochemical and catalytic characteristics, optimal conditions of catalysis, cytotoxicity, etc. Production of abzymes in SLE mice is associated with changes in the differentiation of hematopoietic stem cells of bone marrow, increase in lymphocyte proliferation, and significant suppression of cell apoptosis in different organs. In this chapter, abzymes with different catalytic activities in SLE are described

Minor and Trace Elements in Whole Blood, Tissues, Proteins and Immunoglobulins of Mammals

Microelements play different important roles in many physiological processes in all biological systems in both normal physiological and pathological conditions. They take part in the transport of nutrients and gases, support temperature, acid-base balance, homeostasis of the human organisms, maternal and child mental health, the functioning of enzymes, protein and DNA syntheses, cytoskeleton activation, etc. We have performed simultaneous determination of a number of minor and trace elements in whole blood and tissues of mammals by two-jet plasma atomic emission spectrometry (TJP-AES). TJP-AES allows direct analysis of powders without wet acid digestion and can be used for analysis of both large and small amount of the sample, which is important for biomedical investigations with humans and experimental animals. In addition, a content of different elements in preparations of human immunoglobulins was estimated by TJP-AES as well as using different physicochemical methods, the functional role of metal ions in antibodies functioning was analyzed. The analysis of the relative activity of antibodies with catalytic activity (abzymes) in the hydrolysis of DNA, RNA, proteins, peptides and oxidation-reduction reactions and the role of metal ions in the catalysis of these reactions by abzymes were carried out

Human Milk Lactoferrin and Antibodies: Catalytic Activities, Complexes, and Other Features

Human milk is a source of biologically active proteins, including lactoferrin (LF) and antibodies (Abs). These proteins are considered as the most polyfunctional proteins of human milk. Apparently, human milk is not a simple mixture of proteins and peptides: recently it was shown that human milk contains stable supramolecular protein complex, composed of LF, α‐lactalbumin, milk albumin, β‐casein, IgG, and sIgA molecules. We believe that the whole set of different biological functions of the individual milk proteins is significantly supplemented by features of their complexes

Immune System Dysregulation and Autoimmunity in Schizophrenia: IgGs from Sera of Patients with Several Catalytic Activities

Schizophrenia is usually a progressive mental illness with very different polymorphic symptoms. Several different theories of schizophrenia were discussed; the causes of this disease are not yet clear. Destruction of DNA, RNA, and myelin basic protein (MBP) by inflammation caused by autoimmune reactions has been revealed. Healthy humans usually do not develop abzymes. It was shown that DNase, RNase, and MBP-hydrolyzing abzymes are easily detectable at the beginning of different autoimmune diseases (AIDs). During the development of spontaneous and induced AIDs in mice, a specific reorganization of their immune system associated with the generation of abzymes hydrolyzing different autoantigens was revealed. SCZ is currently not assigned to classical autoimmune diseases. However, the sera of approximately 30% of SCZ patients demonstrated a high level of anti-DNA Abs (comparing to 37% of SLE patients); abzymes hydrolyzing DNA, RNA, and MBP were revealed in 80–100% of SCZ patients. The site-specific hydrolysis of four known SCZ-specific microRNA playing an important role in the regulation of several genes functioning was revealed. Anti-MBP IgGs hydrolyze specifically only MBP but not other proteins. The data indicate that SCZ patients may to a certain extent show similar to SLE and MS patients’ typical signs of autoimmune processes

Deoxyribophosphate lyase activity of mammalian endonuclease VIII-like proteins

AbstractBase excision repair (BER) protects cells from nucleobase DNA damage. In eukaryotic BER, DNA glycosylases generate abasic sites, which are then converted to deoxyribo-5′-phosphate (dRP) and excised by a dRP lyase (dRPase) activity of DNA polymerase β (Polβ). Here, we demonstrate that NEIL1 and NEIL2, mammalian homologs of bacterial endonuclease VIII, excise dRP by β-elimination with the efficiency similar to Polβ. DNA duplexes imitating BER intermediates after insertion of a single nucleotide were better substrates. NEIL1 and NEIL2 supplied dRPase activity in BER reconstituted with dRPase-null Polβ. Our results suggest a role for NEILs as backup dRPases in mammalian cells

IgG antibodies with peroxidase-like activity from the sera of healthy Wistar rats

AbstractVarious catalytic antibodies or abzymes (Abzs) have been detected recently in the sera of patients and animals with many autoimmune diseases, where their presence is most probably associated with autoimmunization. Normal humans or animals usually do not contain Abzs. In contrast, polyclonal Abzs from healthy humans and animals have an intrinsic superoxide dismutase activity and catalyze formation of H2O2 (Wentworth et al., 2000, Proc. Natl. Acad. Sci. USA; 2001, Science). Here, we present the first evidence showing that highly purified native IgGs from the sera of healthy Wistar rats interact with H2O2 and possess peroxidase-like activity. Specific peroxidase activity of IgG preparations from the sera of 10 rats varied in the range 1.6–27% as compared with that for horseradish peroxidase (100%). Antioxidant enzymes such as superoxide dismutases, catalases, and glutathione peroxidases are known to represent critical defence mechanisms for preventing oxidative modifications of DNA, proteins, and lipids. Antioxidant peroxidase activity of Abzs can also play an important role in the protection of organisms from oxidative stress as well as in oxidation of toxic compounds

Kinetics of substrate recognition and cleavage by human 8-oxoguanine-DNA glycosylase

Human 8-oxoguanine-DNA glycosylase (hOgg1) excises 8-oxo-7,8-dihydroguanine (8-oxoG) from damaged DNA. We report a pre-steady-state kinetic analysis of hOgg1 mechanism using stopped-flow and enzyme fluorescence monitoring. The kinetic scheme for hOgg1 processing an 8-oxoG:C-containing substrate was found to include at least three fast equilibrium steps followed by two slow, irreversible steps and another equilibrium step. The second irreversible step was rate-limiting overall. By comparing data from Ogg1 intrinsic fluorescence traces and from accumulation of products of different types, the irreversible steps were attributed to two main chemical steps of the Ogg1-catalyzed reaction: cleavage of the N-glycosidic bond of the damaged nucleotide and β-elimination of its 3′-phosphate. The fast equilibrium steps were attributed to enzyme conformational changes during the recognition of 8-oxoG, and the final equilibrium, to binding of the reaction product by the enzyme. hOgg1 interacted with a substrate containing an aldehydic AP site very slowly, but the addition of 8-bromoguanine (8-BrG) greatly accelerated the reaction, which was best described by two initial equilibrium steps followed by one irreversible chemical step and a final product release equilibrium step. The irreversible step may correspond to β-elimination since it is the very step facilitated by 8-BrG

Milk Exosomes: Isolation, Biochemistry, Morphology, and Perspectives of Use

Cells of the multicellular organisms communicate with each other in many different ways, among which extracellular vesicles play a unique role. Almost all cell types secrete vesicles into the extracellular space and deliver their contents to recipient cells. Today, one of the groups of extracellular vesicles that is of particular interest for studying is exosomes—membrane vesicles with a diameter of 40–100 nm. Exosomes are secreted by cells and found in various biological fluids—blood, tears, saliva, urine, cerebrospinal fluid, and milk. Exosomes provide not only targeted delivery of molecular signals to recipient cells but also carry unique markers, which makes them a promising substrate in diagnostic studies, primarily due to their small RNA and protein contents. The milk of cows, horses, humans, and other mammals is a unique source of exosomes since these organisms can produce liters of milk per day, which is much higher than the volume of exosomes produced in cell culture fluid or blood plasma. Unfortunately, milk exosomes are currently much less studied than exosomes of blood or culture fluid. This review examines the methods of the isolation, biochemical analysis (composition of proteins, lipids, and nucleic acids), morphology, and prospects for the use of milk exosomes