[Analysis of morphological manifestations of the inflammatory reaction in wistar rat spinal cord in experimental model].

Morphological changes in the spinal cord of rats with different intensity of pathological symptoms were studied at the peak of the experimental encephalomyelitis development. Light-microscopical and immunohistochemical methods were used. Distribution of proliferating cell nuclear antigen (PCNA), astrocyte marker - glial fibrillar acidic protein (GFAP), and microglia and macrophage marker Iba-1, was studied. Heterogeneity in morphological manifestations of the experimental allergic encephalomyelitis was shown. Four typical patterns of morphological manifestations of the disease were demonstrated depending on the preferential involvement of pia mater, vessels, spinal cell nuclei or conductive tracts in the pathological process.

[Disordered permeability of the hemato-encephalic barrier in the development of allergic processes of the nervous system]. / Narushenie pronitsaemosti gematoéntsefalicheskogo bar'era pri razvitii allergicheskikh protsessov v nervnoi sisteme.

A single intravenous injection of dimethyl sulfoxide disturbed permeability of the blood-brain barrier (BBB) and caused passage of rhodamin from the blood into the brain in guinea pigs. Brain microinjury, injection of Freund's complete adjuvant or dimethyl sulfoxide increased BBB permeability to brain antigens detected in the animals' blood as early as the first 24 hours after the procedure. Antibodies appeared in the serum and/or delayed type hypersensitivity cell reactions formed in some of the animals later. Daily intraperitoneal dimethyl sulfoxide injections led to increase of the morbidity and mortality indices among animals with experimental allergic encephalomyelitis induced by sensitization with myelin basic protein and Freud's complete adjuvant. The results of the experiment show the important role of BBB permeability in the pathogenesis of experimental allergic encephalomyelitis.

[Immunomorphologic features of experimental allergic encephalomyelitis induced by the administration of tryptophan peptide]. / Immunolomorfologicheskie osobennosti éksperimental'nogo allergicheskogo éntsefalomielita, indutsirovannogo vvedeniem triptofanogo peptida.

Three patterns of EAE with different morbidity and mortality rates were induced in the guinea pigs inoculated with various doses of tryptophane peptide (TP) and complete Freund's adjuvant. TP-sensitized animals manifested the delayed type hypersensitivity (DTH) reactions to TP and circulating anti-TP and -BPF antibodies were not found, polypeptide fraction of myelin basic protein (BPF while a A correlation was revealed between the DTH-reactions and EAE development. Intracutaneous TP and BPF injections at the early period before the EAE onset resulted in reduction of morbidity rate from 90 to 50 per cent. For the first time with the help of modified Marchi method demyelination has been shown to be highly marked in CNS tissue process in CNS can be caused by cell-mediated immune of animals given TP. It is supposed that the demyelinating reaction to encephalitogenic fragment of BP molecule. The data indicate a possibility of EAE inhibition by means of TP and BPF injections in saline solution.

[A method of detecting demyelinated nerve tissue in experimental allergic encephalomyelitis]. / Sposob vyiavleniia demielinizatsii v nervnoi tkani pri éksperimental'nom allergicheskom éntsefalomielite.

A method of rapid pathomorphological diagnosis of demyelinization with a simultaneous detection of cell elements in the nervous tissue has been described. The method tested on the model of experimental allergic encephalomyelitis (EAE) is a modified method of Marchi with subsequent staining of histological sections with toluidine blue. Due to a shorter period of nervous tissue exposure to potassium bichromate and osmium acid solutions (from 6-8 weeks to 5 days) the cells preserve their ability to uptake the dye and the endurance of histological sections increases. Their thickness (2-3 microns) makes it possible to examine them in immersion magnification of the light microscope. Using the above method, we succeeded in revealing hematogenic and glial elements in demyelinating foci in the central nervous system of animals with EAE. The method described can be used for studying pathomorphology of multiple sclerosis and other demyelinating diseases in humans and their experimental models, as well as for the express diagnosis of demyelinization in pathoanatomical practice.

[Immunomorphological characteristics of experimental allergic encephalomyelitis induced by an encephalitogenic polypeptide]. / Immunomorfologicheskie osobennosti éksperimental'nogo allergicheskogo éntsefalomielita, indutsirovannogo éntsefalitogennym polipeptidom.

Encephalitogenic, immunogenic properties of the polypeptide fraction of myelin basic protein (FBP) and CNS lesions have been examined in animals with experimental allergic encephalomyelitis (EAE). FBP was isolated from bovine spinal cord using column chromatography. Administration of 1.0 or 0.1 microgram FBP mixed with complete Freund adjuvant caused neurological and histological EAE manifestations in 76% and 26% of guinea-pigs, respectively. Circulating anti-FBP antibodies were not found in sensitized animals, whereas the incidence and intensity of skin reaction of delayed type hypersensitivity to FBP correlated with the development of EAE and the onset of the disease. Perivascular cell infiltration and demyelination noted in the spinal cord and brain of guinea-pigs were similar to those observed after inoculation of the brain white matter or brain tissue homogenate.

[Dynamics of pathomorphologic changes in experimental allergic encephalomyelitis]. / Dinamika patomorfologicheskikh izmenenii pri éksperimental'nom allergicheskom éntsefalomielite.

The new method of simultaneous identification of myelin degradation products and cellular elements in the demyelinated nervous tissue allowed one to determine some previously unknown regularities in the interaction of demyelination and inflammation processes during experimentally induced allergic encephalomyelitis. The most significant feature in the pathomorphology of this disease is shown to be the change in osmiophilia and the amount of myelin degradation products in the demyelination foci, with every stage of periaxonal changes corresponding to a certain type of cellular reactions. A close relation is revealed between the demyelination and inflammation processes determining the structure of demyelination foci at different stages of the disease.

[Neurologic manifestations and periaxonal demyelination in the central nervous system in different forms of experimental allergic encephalomyelitis]. / Nevrologicheskie proiavleniia i periaksonal'naia demielinizatsiia v tsentral'noi nervnoi sisteme pri razlichnykh formakh éksperimental'nogo allergicheskogo éntsefalomielita.

Comparing the neurological manifestations of experimentally-induced allergic encephalomyelitis (EAE) with the topography of developing demyelinization in the central nervous system of guinea-pigs allowed the authors to identify three forms of the diseases, namely spinal, cerebral and mixed. The spinal form caused by myelin decay in the lumbosacral segments of the spinal cord was expressed in the form of pareses and paralyses affecting the hind paws and also pelvic disorders. In the cerebral form, demyelinization was localized in the brain and was most frequently attended by vestibular disturbances. The mixed form characterized by pathological changes in both the spinal cord and brain was identified largely on the histological basis. In some animals (several of which died), EAE ran its course without apparent neurological symptoms and was identified only histologically.

[Prevention of experimental allergic encephalomyelitis in guinea pigs by treatment with magnetophores]. / Predotvrashchenie éksperimental'nogo allergicheskogo éntsefalomielita u morskikh svinok vozdeistviem magnitoforov.

Subcutaneous application of magnetophores with a field intensity of 210 ersted prevented the development of experimental allergic encephalomyelitis (EAE) in guinea-pigs. The magnetophores appeared efficacious both at the beginning of the induction period and in the second half of the latent period, i.e. within the first two weeks after injection of encephalitogenic suspension. Application of magnetophores after the appearance of the neurological signs of EAE was ineffective. Magnetophores did not affect cellular or humoral response in animals. It may be assumed that the effect of magnetophores is related to the increased resistance of nerve cells to the immunopathological action of the immune response factors, a topic for further studies.

[Induction of experimental allergic encephalomyelitis with encephalitogenic myelin proteins from the spinal cord of a bull]. / Induktsiia éksperimental'nogo allergicheskogo éntsefalomielita éntsefalitogennymi belkami mielina iz spinnogo mozga byka.

A homogenous base protein, exhibiting high encephalitogenic activity towards guinea pigs and rabbits, was isolated from bovine spinal cord using column chromatography. Administration of the preparation obtained together with Freund's adjuvant into the animals caused development of neurogic symptoms typical for experimental allergic encephalomyelitis as well as formation of demyelinization foci both in spinal cord and in brain of guinea pigs and rabbits.

[Isolation and analysis of encephalitogenic fractions of spinal cord proteins]. / Vydelenie i analiz éntsefalitogennykh fraktsii belkov spinnogo mozga.

Main encephalitogenic protein was isolated from bovine medulla spinalis and separated into homogenous polypeptide fractions by gel filtration; some of these fractions had the high encephalitogenic activity. The main protein and its fractions, possessing the encephalitogenic activity, caused a development of cross-reacting antibodies and a sensitization to intracutaneous administration of encephalitogenic preparations in animals. Non-encephalitogenic main protein sensitized animals only to this protein and did not induce the formation of distinct amount of antibodies. The amino acid composition of the encephalitogenic polypeptide is exhibited.

[Effect of antibodies to rat and human cerebral cortex and white matter on heterologous T- and B-cells]. / Deistvie antitel k kore i belomu veshchestvu golovnogo mozga krysy i chelovaka na geterologichnye T- i B-kletki

A study was made of the cytotoxic and complement-fixation activity of the antisera to the cortex and white matter of the rat and human brain upon the mouse and rat thymus and bone marrow cells. The cytotoxicity test proved to be more sensitive and precise. Cytotoxins to rodent thymocytes were revealed on ly in the antisera against the human brain cortex; at the same time they were revealed both in the antisera against the cortex and against the white matter of the rat brain (much more was found in the former). The sera against the rat brain cortex lost their cytotoxicity after the exhaustion with the same antigen, but retained it when the exhaustion was carried out by the white matter.

[Presence of cross-reacting thymus and brain antigens in the cerebral cortex]. / Nalichie perekrestno reagiruiushchikh antigenov timusa i mozga v kore golovnogo mozga

Rabbit antisera against antigens of mouse, rabbit, guinea pig and human whole brain cross-reacted in the cytotoxic test with the lymphocytes of the thymus, lymph nodes and the spleen of these animal species. Mouse thymocytes were most sensitive to the antibrain sera (cytotoxic index -- 63--100 per cent); cells from other mouse lymphoid organs and lymphocytes of rabbit, guinea pig and man were more resistant. Bone marrow lymphocytes were not damaged by any of these sera. The antigens which induced the cytotoxic properties of the sera were found only in the human cerebral cortex, but not in the white matter of the brain stem.

[Influence of antilymphocyte sera on the development of experimental allergic encephalomyelitis]. / Izuchenie vliianiia antilimfotsitarnykh syvorotok na razvitie éksperimental'nogo allergicheskogo éntsefalomielita

Experimental allergic encephalomyelitis (EAE) was induced in guinea pigs by sensitization of myelinomas of homologous or heterologous (rabbit) brain in the complete Freund's adjuvant. Antilymphocytic serum (ALS) obtained by immunization of rabbits with the lymphocytes of the lymph nodes of guinea pigs was injected subcutaneously for 3--6 days at the early periods before or after the sensitization. ALS produced a marked inhibitory action on the development of the neurological signs of EAE and of histological changes in the form of demyelinization and perivascular cell infiltration in the lumbo-sacral and cervical portions of the spinal cord. Administration of ALS beginning from the 3rd--5th day before the sensitization or from the date of the EAE induction proved to be the most effective. When the injections were started from the 7th or the 12th day after the sensitization an increase in the incidence of the disease occurred in the grooups. A fall of morbidity correlated with a reduction of percentage of positive skin tests in response to the intradermal injection of a homologous myelin. No reduction in the production of the complement-fixing, antibodies to the heterologous antigen was seen in the animals given ALS. This pointed to the participation of cell factors in the development of the pathological process.