Allergic Encephalomyelitis Research Articles

Induction of Autoimmune Diseases with Adjuvants: Separation of Delayed Hypersensitivity and Antibody Formation from Diseases in Experimental Thyroiditis and Aspermatogenesis with <i>Legionella</i> Adjuvant

The induction of autoimmune diseases in animals was studied with Legionella and mycobacteria as adjuvants, emulsified in oil with antigen extracts of thyroid, testis, spinal cord, and peripheral nerve. Both adjuvants were equally effective in inducing delayed hypersensitivity and humoral antibody to the tissue antigens. The Legionella adjuvant, however, induced little or no thyroiditis and aspermatogenesis, whereas the mycobacterial adjuvant induced thyroiditis and aspermatogenesis. Both adjuvants caused allergic encephalomyelitis and peripheral neuritis. The results indicated that delayed hypersensitivity by itself may not be sufficient to cause thyroiditis and aspermatogenesis. Legionella adjuvant apparently lacked the ability to induce certain immune factor(s) which caused the disease in experimental thyroiditis and aspermatogenesis. The differential properties of Legionella adjuvant and mycobacterial adjuvant in inducing immunity to autoantigens could provide a useful means to study the pathogenic and immunoregulatory mechanisms of some experimental autoimmune diseases.

Anti-Myelin Basic Protein Antibody in Experimental Allergic Optic Neuritis and Encephalomyelitis

We produced demyelinating optic neuritis and encephalomyelitis in juvenile strain 13 guinea pigs by sensitization with optic nerve myelin. Three distinct clinical courses were noted: a severe, acute optic neuritis associated with a rapidly fatal encephalomyelitis; a mild, chronic optic neuritis with a nonfatal encephalomyelitis; and an initially mild disease followed by an acute exacerbation of optic neuritis and fatal encephalomyelitis. Clinically mild disease was associated with elevated levels of anti-myelin basic protein antibody, while severe disease was associated with extremely low antibody levels.

Cataracts and Allergic Encephalomyelitis

Juvenile guinea pigs developed cataracts during severe acute allergic (autoimmune) encephalomyelitis produced actively by injection of central nervous system antigens in complete Freund’s adjuvants. C

Analysis of Autoimmunity through Experimental Models of Thyroiditis and Allergic Encephalomyelitis

Publisher Summary This chapter presents the relationship between the normal state of self-tolerance and its abnormal corollary, autoimmunity. The several possible bases for loss of self-tolerance, including failure of immune regulation and abnormal presentation of potential self-antigens, are considered in terms of current understanding of cellular and humoral immune processes. A particularly thorough evaluation of suppressor cells and their possible role in self-tolerance and autoimmunity is presented. The pathogenic mechanisms that may be involved in autoimmune disease are examined in the light of two familiar experimental models, allergic encephalomyelitis and autoimmune thyroiditis. The pathogenic potential of cellular autoimmune responses in encephalomyelitis, on the one hand, and of autoantibody responses in thyroiditis, on the other, indicates the very different pathogeneses, which may operate in autoimmunity. The various mechanisms that are responsible for the loss of tolerance to self antigens can be divided into three general categories. First, abnormalities may occur in the regulatory mechanisms that control the normal immune response. Second, a component of self that was once sequestered and nonimmunogenic may become exposed and presented in an antigenic form to the immune system. Third, a normally tolerated self component may for some reason circumvent the prevailing regulatory mechanisms and activate one or more arms of a normal immune system. Numerous factors are involved in autoimmune diseases including genetic control at major histocompatibility complex (MHC) and non-MHC loci, immunologic regulatory mechanisms, self-nonself recognition, and logistics and/or nature of the target autoantigens.

Allergic encephalomyelitis: evidence for lack of significant encephalitogenic activity of purified peptide L in the monkey.

Allergic encephalomyelitis: evidence for lack of significant encephalitogenic activity of purified peptide L in the monkey.

A study of some oxido-reductases in nerve tissue culture

Changes in the activity of succinate dehydrogenase and NAD- and NADP-diaphorases under the influence of immune serum from animals with experimental allergic whooping-cough encephalomyelitis were studied in a dissociated culture of neonatal rat cerebellum. An increase of activity was found in the oligodendrocytes after exposure for 3 h to the immune serum and a decrease in activity of these enzymes in the same cells after exposure of the cultures to the serum for 12 h. By contrast to the oligodendrocytes, high activity of all these enzymes was found in the astrocytes after exposure for 12 h to the serum.

Allergic encephalomyelitis: modification of the response by synthetic membrane structures containing bovine myelin basic protein and cerebroside

Allergic encephalomyelitis: modification of the response by synthetic membrane structures containing bovine myelin basic protein and cerebroside

Effect of adjuvant disease in rats on cyclophosphamide and isophosphamide metabolism

After the injection of a variety of arthritogenic adjuvants into male Wistar rats, hepatic activation of cyclophosphamide and isophosphamide is rapidly and profoundly depressed. This selective injury is largely reversible with phenobarbital and principally restricted to the liver microsomal protein fraction, which demethylates aminopyrine and N, N-dimethylaniline and generates “alkylating metabolites” from cyclophosphamide in vitro. Evidence is presented, based upon both metabolite excretion studies and the duration of hexabarbital-induced hypnosis, that this phenomenon is not an artifact in vitro and must be seriously considered in evaluating both the efficacy of potential anti-arthritic drugs against the rat adjuvant arthritis and their toxicity in these arthritic animals. A quantitative separation of two pathological responses to the same adjuvant may be obtained: (1) in Buffalo rats, whose liver metabolism may be profoundly impaired while they suffer minimal (or no) arthritis after being inoculated with adjuvants which are truly arthritogenic in other rat strains; (2) with Mycobacterium tuberculosis dispersed in methyl oleate, which induces minimal arthritis in Wistar rats, but nevertheless impairs their liver metabolism over a prolonged period (14 days or more). Drug metabolism appeared to be normal in rats with two other immunologically mediated “inflammatory diseases” (graft vs host disease and allergic encephalomyelitis) and in other rodents examined after adjuvant inoculations. A novel bioassay for cyclophosphamide and isophosphamide metabolites is described which utilizes their ability to prevent grafted rat lymphocytes from initiating a graft vs host reaction in tolerant recipient rats. At least four alkylating metabolites of cyclophosphamide were found in rat bile and tentatively identified by thin-layer chromatography. The possible error in relying on changes in urinary excretion (rather than biliary excretion) of drug metabolites as a guide to changes in hepatic xenobiotic metabolism is discussed.

Hydrosoluble adjuvant-active mycobacterial fractions of low molecular weight

Mycobacteria [1 ], cell walls from human and non human mycobacterial strains [2, 3] as well as myco- bacterial waxes D with a nitrogen-containing moiety [4, 5] possess a 'Freund's adjuvant effect' [1]; all these substances lead also to the production of delayed hypersensitivity and of certain disease states such as allergic encephalomyelitis or adjuvant arthritis [5, 6]. These different insoluble active fractions of high molecular weight contain a polysaccharide (Poly, mainly an arabinogalactan [7-9] ) linked to a peptidoglycan (PA) [ 10-12]. Poly-PA constitutes the hydrosoluble moiety which is joined by ester linkages to the lipidic part (Lip, mycolic acids as in wax D). Previously we described [13] the preparation by a mild extraction technique of a hydrosoluble adjuvant-active substance (Poly-PA) from the delipidated cells of the human mycobacterial strain Peurois which did no more elicit the arthritis inducing effect. These studies were achieved quite independent- ly from those reported at the same time by others [14, 15]; their hydrosoluble polysaccharide fractions obtained by different procedures required either the preparation of purified cell walls which were further submitted to an enzymic digestion or a chemical treatment (catalytic hydrogenation) of delipidated BCG cells. All these adjuvant-active hydrosoluble fractions presented a high molecular weight. This note deals * 18th Communication on mycobacterial adjuvant-active substances. with the preparation of adjuvant-active fractions of low molecular weight. Two types of compounds were characterized: a first one where the sugars remained unchanged during the preparation steps ('native' type) and a second one where the sugars were acetylated. 2.

Allergic encephalomyelitis: Characterization of the determinants for delayed type hypersensitivity

Three non-encephalitogenic peptides derived from the encephalitogenic myelin basic protein of the central nervous system, produce delayed type hypersensitivity responses and elicit delayed skin reaction in guinea pigs sensitized with either peptide, the encephalitogenic tryptophan region (peptide E) or the basic protein. The amino acid sequence of the peptides is N-Acetyl-Ala-Ser-Ala-Gln-Lys-OH, forming the N-terminal region of the basic protein molecule, H-Gly-Ser-Leu-Pro-Gln-Lys-OH and H-Gly-Ala-Glu-Gly-Gln-Lys-OH representing residues number 69–74 and 117–122 of the basic protein respectively.

Allergic encephalomyelitis: effect of complement depletion with cobra venom.

Conclusion and SummaryComplement depletion of rats by cobra venom factor had only minor and variable effects on the hyperacute form of EAE. It appears likely that the exudation of polymorphonuclear leukocytes and massive amounts of fibrin in this condition is not dependent on complement. However, it is not possible to eliminate all traces of complement with cobra factor. Therefore, it is theoretically possible that small amounts of complement, too little to be detected by hemolytic activity or gel diffusion, might accumulate in the EAE lesions during the 1- to 3-day period in which they evolved. However, inhibition of the neutrophil accumulation of nephrotoxic serum glomerulitis attested to the efficacy of the cobra factor. This internal control provided evidence against the binding of C3 and terminal components, at least for the last 3 hr of development of EAE lesions. As C3 levels fall within 4 hr of the initial injection, it is most probable that complement depletion spanned the time during which EAE l...

Ribonucleoside 2′,3′-cyclic phosphate diesterase activity and cerebroside levels in vertebrate and invertebrate nerve

Ribonucleoside 2′,3′-cyclic phosphate diesterase, an enzyme located in myelin was examined in neural tissues from several vertebrate and invertebrate species. Cerebroside levels in these tissues were also determined as an index of myelin. An attempt was made to determine if a quantitative relationship existed between diesterase activity and myelin content. Diesterase activity varied widely being highest in mammalian central nervous system. Tissue from the central nervous system of the turtle, skate and dogfish possessed low activity, dogfish nerve being only about 1/500 as active as dog white matter. Myelin content (as reflected through cerebroside levels) of tissue from the central nervous system of the lower organisms was not greatly different from that of corresponding mammalian tissues. Thus there was no quantitative relationship between enzyme activity and myelin content. Nerve tissue from a variety of invertebrates, squid, octopus, crab, prawn and starfish, possessed no diesterase activity and were essentially devoid of cerebrosides. Diesterase activity in the brain and spinal cord of ‘Jimpy’ mice, a mutant with defective myelination, was severely reduced being only about 1 and 10% of normal in the brain and spinal cord respectively. Cerebrosides were similarly drastically reduced. The spinal cord of guinea pigs afflicted with allergic encephalomyelitis, a disease characterized by demyelination, possessed normal levels of diesterase activity. Surprisingly, these tissues also contained normal, or slightly elevated, levels of cerebrosides. It is suggested that the quantitative degree of demyelination in the terminal stages of this disease, at least in the spinal cord of guinea pigs, is not great. These studies are consistent with an association of ribonucleoside 2′,3t3'-cyclic phosphate diesterase with myelin. The enzyme is present only in those nerve fibers which contain cerebrosides and is decreased in mutant mice with deficient myelination. However, there is no quantitative relatioship between diesterase activity and cerebroside content. We therefore suggest caution in using the diesterase as a quantitative marker for myelin until more definitive experiments are performed.

Allergic encephalomyelitis: A comparison of the encephalitogenic A1 protein from human and bovine brain

The chemical and biological properties of the human encephalitogenic basic protein was compared to that from bovine brain. Both proteins are highly basic and contain approximately 25 net positive charges at pH 6. They each contain one residue of tryptophan per mole but no cysteine. The electrophoretic migration in polyacrylamide gel at pH 4.3 and 8.0 was almost identical. The sedimentation coefficient was estimated to be 1.34 S, and their molecular weight 18,000–19,000 daltons with the human protein possibly larger. The optical rotatory dispersion studies suggested a random-coil structure; no α-helix or β-form was indicated. The encephalitogenic activity of the two proteins measured in the guinea pig was approximately the same. Their ability to combine with antibody prepared against the bovine protein was similar as determined by the hemagglutination-inhibition test. Both proteins were found to induce a significant delayed skin reaction in guinea pigs regardless of whether the human or bovine protein was used to produce sensitized cells. Thus, the physical, chemical, and biological properties of these two basic proteins are similar; the amino acid sequence is not identical, however, as revealed by the tryptic peptide maps.

Allergic encephalomyelitis: Preparation of the encephalitogenic basic protein from bovine brain

A homogeneous preparation of the encephalitogenic A1 protein was obtained from the bovine brain or spinal cord by cation-exchange chromatography on either Bio-Rex 70 or Cellex P. The preparations appeared homogeneous by polyacrylamide gel electrophoresis at pH 4.3 and 8.9 and migrated identical to the basic protein prepared from bovine spinal cord. These preparations were encephalitogenic at the levels of 0.1 μg or higher per guinea pig and combine with antibody produced against the bovine spinal cord basic protein as shown by the passive hemagglutination inhibition test. It was concluded that the A1 protein is identical, whether derived from brain or spinal cord, and that its properties are independent of the final method of purification following acid extraction from the defatted tissue.

Passive transfer of adjuvant-induced arthritis and allergic encephalomyelitis in rats using thoracic duct lymphocytes.

SUSPENSIONS of cells derived from lymph nodes or the spleen have been used to transfer adjuvant-induced arthritis1,2 and allergic encephalomyelitis3,4 in rats. We have now successfully transferred both these experimental diseases in rats using cells obtained from the thoracic duct.

A packed cell volume (“cytocrit”) method for measuring swelling of rat brain cells exposed to sera of rabbits with allergic encephalomyelitis

A cytocrit method for determining the swelling effect of cytotoxic antibodies was adapted for use with fresh rat brain cells in saline acted upon by sera of rabbits showing paralysis of AE. Detailed descriptions of the procedure, and advantages and disadvantages of the method are presented. Brain cells in balanced saline show swelling; this swelling is reduced by about 76% by adding 0.1 ml of normal serum to each ml of cell suspension. The difference between swelling with normal serum and with AE serum is believed to represent the swelling effect of cytotoxic antibodies in AE serum. Swelling of rat brain cells with AE sera is temperature-dependent. The curve of swelling at 37°C is logarithmic through 210 minutes of incubation. Control swelling is of slightly less magnitude if control sera are used within 10 days of drawing than if used 15–41 days after drawing. Using the same experimental and control sera at 37°C in 3 independent runs under the same conditions, results with control serum agreed within 0.12%; with experimental serum, within 23.8%.

The effects of antibrain antibodies on brain cell suspensions as determined by a cytocrit method

One of the earliest changes seen in histological sections of the central nervous system of animals with allergic encephalomyelitis is swelling of myelin and glia. 1 Such effects have also been noted in myelin and glia in cultures of CNS tissue exposed to sera of animals with AE and of human MS patients. 2–4 A cytocrit (packed cell volume) method, used with other types of cells 5,6 was adapted for measuring the swelling effect of AE sera on brain cell suspensions. A detailed description of this method is presented in a separate communication. 7 Sera from rabbits inoculated with encephalitogen and showing paralysis of AE, added to saline suspensions of rat brain cells, causes an increase in the cytocrit. Some results of the application of this method are presented in this paper.

Allergic encephalomyelitis: inhibition of cellular passive transfer by x-irradiation.

Allergic encephalomyelitis: inhibition of cellular passive transfer by x-irradiation.

Allergic encephalomyelitis: the physico-chemical properties of the basic protein encephalitogen from bovine spinal cord

A protein encephalitogen, isolated in a homogeneous state from bovine spinal cord, was found to have unusual properties. It was highly basic, containing 38 moles/ mole of basic amino acids (arginine, lysine, histidine) and only 7 moles/mole of acidic amino acids (glutamic and aspartic acid); the calculated isoionic point exceeded 12. Only one tryptophan (determined by three independent methods) and two methionine residues were present; no carbohydrate or lipid was associated with the isolated protein. Although similar to certain histone fractions, it differed from these proteins in its much higher content of histidine, glycine, and serine, and its lower content of alanine. The N-terminal position is blocked. The molecular weight determined by sedimentation equilibrium techniques was 16,400 daltons; by sedimentation-viscosity, 16,200; and by UV absorption studies based on the tyrosine-tryptophan content, 16,200. Estimates of molecular weight based on the amino acid analysis gave values of 15,500–18,200 daltons. An intrinsic viscosity of 9.27 ml/g and viscosity increment of 12.9 were found. From these data an axial ratio (a/b) of approximately 10:1 (assuming no hydration and a prolate ellipsoid) was calculated, revealing that the molecule is highly unfolded and approximates a rod-like shape. This property accounts for the unexpected behavior of this basic protein on gel nitration which has led to erroneously high molecular weight values. A small degree of aggregation was observed as indicated by the high molecular weight estimate of 22,300 found near the cell bottom using a long-column sedimentation equilibrium technique. No evidence of aggregation was observed at pH 2.6, 7.0, or 9.5 during sedimentation velocity studies. An S 0 20, w value of 1.72S was found at pH 2.6, ionic strength 0.25. Considerable variation of the S 20, w was found with protein concentration, but not with pH. The highly extended conformation of the Al molecule, found from viscosity studies, is compatible with its resistance to denaturation; no loss in encephalitogenic activity was found following heating at 100 ° for 1 hr, treatment with 8 m urea for 8 hr, or incubation at pH 10.0 for 8 hr. Moreover, these procedures do not diminish interaction with antibody measured by the Ouchterlony and passive hemagglutination inhibition tests. Polyacrylamide gel electrophoresis also revealed no drastic changes in conformation arising from these procedures. It was concluded from these data that hydrophobic and hydrogen bonding play a minor role in the overall conformation of the A1 protein molecule. This property is of interest in considering the role of this protein as a membrane component.

Allergic encephalomyelitis: Isolation and characterization of encephalitogenic peptides from the basic protein of bovine spinal cord

The basic protein encephalitogen from bovine spinal cord was digested with pepsin for 2 hr; the resulting digest was subjected to gel filtration on a column of Sephadex G-25-G-75. Peptide families obtained in this way were highly encephalitogenic. Upon fractionation of the peptides on a column of Cellex-P, 19 peptides were obtained as demonstrated by high-voltage electrophoresis. After desalting of specific peptides on a column of Sephadex G-10-G-25 11 homogeneous peptides were isolated. The data showed that two of these peptides, referred to as E (16 amino acid residues) and E1 (26 amino acid residues), are more potent in inducing EAE in guinea pigs than the original A1 protein. The amino acid composition of Peptide E and E1 were similar; each contained one tryptophan residue, the only one found in the A1 protein (142 residues). Serine was identified as the N-terminal amino acid of Peptides E and E1 and also Peptide D which contains tryptophan, but is nonencephalitogenic. The results indicate that these peptides originate from the same region of the A1 molecule, and support the previous proposal that the EAE determinant is the property of the primary structure of the A1 protein as defined by the specific amino acid sequence of Peptide E.