PhD / The aims of this study were to test the efficacy of immunoglobulin and its Fab and Fc fragment in the treatment of experimental autoimmune neuritis (EAN) in Lewis rats, to investigate which portion of immunoglobulin is operative in the effect of IVIg, and to clarify the possible mechanisms by which immunoglobulin exerts its action in the treatment of rats EAN. EAN was induced by immunization with whole bovine peripheral nerve myelin. The immunized rats were randomized into groups, assessed clinically, electrophysiologically, and histologically, and intravenously injected with normal saline, albumin, human IVIg preparation, purified Fab or Fc fragments. The treatment efficacy was compared between normal saline and albumin groups, albumin and IVIg groups, albumin and Fab groups, albumin and Fc groups, Fab and Fc groups, Fab and IVIg groups, and Fc and IVIg groups. Methods of myelin isolation, antibody purification, and Western blot techniques were also applied. The results revealed that treatment with Fc fragment and IVIg at the onset of signs of disease effectively prevented further progression of disease, shortened disease duration, and facilitating recovery from illness as shown in clinical, electrophysiological and histological parameters. In the study which the efficacy of albumin and IVIg was compared, 5 out of 17 rats (29%) in the albumin group and 12 out of 17 (71%) in the IVIg group completely recovered from the clinical disease by day 30. The animals receiving IVIg treatment exhibited lower clinical scores, less prolongation of S wave latencies, better maintained S wave amplitudes, less reduction of distal motor NCVs, better maintained distal and proximal CMAP amplitudes, and lower histological grades. In the study which the efficacy of albumin, Fab fragment, Fc fragment, and IVIg was compared, 0 out of 8 (0%) in the albumin group, 1 out of 8 (13%) in the Fab group, 4 out of 8 (50%) in the Fc group, and 6 out of 9 (67%) rats in the IgG group completely recovered from the clinical disease by day 30. The animals receiving Fc fragment and IVIg treatment exhibited lower clinical scores, less prominent weight loss, less prolongation of S wave latencies, better maintained S wave amplitudes, less reduction of distal motor NCVs, better maintained distal and proximal CMAP amplitudes, and lower histological grades.

PhD / The aims of this study were to test the efficacy of immunoglobulin and its Fab and Fc fragment in the treatment of experimental autoimmune neuritis (EAN) in Lewis rats, to investigate which portion of immunoglobulin is operative in the effect of IVIg, and to clarify the possible mechanisms by which immunoglobulin exerts its action in the treatment of rats EAN. EAN was induced by immunization with whole bovine peripheral nerve myelin. The immunized rats were randomized into groups, assessed clinically, electrophysiologically, and histologically, and intravenously injected with normal saline, albumin, human IVIg preparation, purified Fab or Fc fragments. The treatment efficacy was compared between normal saline and albumin groups, albumin and IVIg groups, albumin and Fab groups, albumin and Fc groups, Fab and Fc groups, Fab and IVIg groups, and Fc and IVIg groups. Methods of myelin isolation, antibody purification, and Western blot techniques were also applied. The results revealed that treatment with Fc fragment and IVIg at the onset of signs of disease effectively prevented further progression of disease, shortened disease duration, and facilitating recovery from illness as shown in clinical, electrophysiological and histological parameters. In the study which the efficacy of albumin and IVIg was compared, 5 out of 17 rats (29%) in the albumin group and 12 out of 17 (71%) in the IVIg group completely recovered from the clinical disease by day 30. The animals receiving IVIg treatment exhibited lower clinical scores, less prolongation of S wave latencies, better maintained S wave amplitudes, less reduction of distal motor NCVs, better maintained distal and proximal CMAP amplitudes, and lower histological grades. In the study which the efficacy of albumin, Fab fragment, Fc fragment, and IVIg was compared, 0 out of 8 (0%) in the albumin group, 1 out of 8 (13%) in the Fab group, 4 out of 8 (50%) in the Fc group, and 6 out of 9 (67%) rats in the IgG group completely recovered from the clinical disease by day 30. The animals receiving Fc fragment and IVIg treatment exhibited lower clinical scores, less prominent weight loss, less prolongation of S wave latencies, better maintained S wave amplitudes, less reduction of distal motor NCVs, better maintained distal and proximal CMAP amplitudes, and lower histological grades.

A neurite auto-imune experimental (NAE) é uma polineuropatia desmielinizante monofásica do sistema nervoso periférico (SNP). A NAE é considerada modelo experimental da síndrome de Guillain-Barré (SGB). Por se tratar de uma doença autoimune, pode ser induzida experimentalmente em camundongos geneticamente susceptíveis, através da imunização com componentes da mielina de nervos periféricos. Para a indução da NAE podem ser utilizados P0 e P2, proteínas da mielina do nervo periférico, ou sequências conhecidas de peptídeos dessas proteínas 180-199 e 58-81 respectivamente, consideradas neuritogênicas, ou ainda transferência adotiva de lifócitos T CD4+, oriundas de camundongos previamente imunizados. Para o presente estudo foram utilizados camundongos fêmeas SJL/J nãográvidas, com idade entre 8 e 12 semanas, pesando de 17 a 20 g. Os animais foram divididos em dois grupos: um controle e outro com NAE. 200 µg da sequência de peptídeos 58-81 de P2 emulsificada em 100 µl de adjuvante de Freund completo (AFC) foram injetados por via subcutânea, em quatro locais na região lombar. Para os controles, foi utilizado solução tamponada de fosfato (PBS), emulsionada em AFC desprovida da sequência 58-81 de peptídeos P2, injetada no mesmo local, na mesma quantidade e forma. Cada camundongo tratado com P2 recebeu 200 ng de toxina pertussis em 100 ?L de PBS intraperitonealmente (i.p.) nos dias 0 e 2 pós-imunização (p.i.). No grupo controle, volumes iguais de PBS e toxina pertussis foram administrados pela mesma via sem o peptídeo. Avaliações da motricidade foram realizadas diariamente até o 60º dia, além de análises funcionais e eletroneuromiográficas. Foram encontradas alterações exclusivamente eletrofisiológicas, desmielinizantes e axonais, em cerca de dois terços dos camundongos. Sendo o camundongo SJL/J considerado o camundongo mais susceptível para a provocação de NAE, os achados do presente estudo indicam a limitação do modelo: ausência de alterações motoras detectáveis clinicamente, ocorrendo distúrbios eletrofisiológicos em apenas parte dos animais. O melhor modelo de NAE continua sendo o provocado no rato Lewis por proteína da mielina periférica bovina. É desejável que se continue buscando modelo experimental de NAE em camundongos, tendo em vista que essa espécie animal é a mais bem estudada na Biologia animal e, por essa razão, dela haver extensa variedade de imunobiológicos disponíveis para estudo da patogenia e fisiopatologia de doenças auto-imunes. / Experimental autoimmune neurits (EAN) is a monophasic demyelinating disease of the peripheral nervous system (PNS). EAN is considered to be the experimental model for Guillain-Barré syndrome (GBS). EAN can be induced in genetically susceptible mice using peripheral myelin components as immunogens: peripheral nerve myelin proteins P0 or P2; peptides sequences of those proteins considered neuritogenic, or the adoptive transfer of TCD4+ lymphocytes from previously immunized mice. In the present study non-pregnant female SJL/J mice aged 8-12 weeks weighint 17-20 g where used. The experimental group was treated as follows. Peptides sequence of P2 (200 µg) emulsified in complete Freund adjuvant (CFA) (100 µl) injected in four sites at the lumbar paravertebral region s.c. Controls were injected in the same sites with equal quantities of phosphate buffer solution emulsified in CFA without the peptides sequence. Each mouse treated with P2 was also treated with 200 ng pertussis toxin in 100 ?L PBS i.p. at the days 0 and 2 post-immunisation. Controls were injected i.p. with equal volumes of PBS and pertussis toxin free of the peptides sequence. Motor strength, posture and coordination were evaluated daily until the 60th day postinoculation besides eletroneuromyographic (EMG) evaluation on the 10th and 30thy days of some mice. No clinical disturbances were observed and in two thirds of the animals demyelinating and axonal features were detected at the EMG. SJL/J mice are considered the most susceptible mouse strain for NAE induction but the findings of the present study indicates the limitations of the model and its reproducibility. The best NAE model is yet the obtained in Lewis rat. It is important to look for a mouse model of EAN because this animal species is the most studied in the animal Biology. The extensive variety of immunobiologic products from mice allows performing studies on the pathogeny or physiopathology of autoimmune diseases more easily.

A neurite auto-imune experimental (NAE) é uma polineuropatia desmielinizante monofásica do sistema nervoso periférico (SNP). A NAE é considerada modelo experimental da síndrome de Guillain-Barré (SGB). Por se tratar de uma doença autoimune, pode ser induzida experimentalmente em camundongos geneticamente susceptíveis, através da imunização com componentes da mielina de nervos periféricos. Para a indução da NAE podem ser utilizados P0 e P2, proteínas da mielina do nervo periférico, ou sequências conhecidas de peptídeos dessas proteínas 180-199 e 58-81 respectivamente, consideradas neuritogênicas, ou ainda transferência adotiva de lifócitos T CD4+, oriundas de camundongos previamente imunizados. Para o presente estudo foram utilizados camundongos fêmeas SJL/J nãográvidas, com idade entre 8 e 12 semanas, pesando de 17 a 20 g. Os animais foram divididos em dois grupos: um controle e outro com NAE. 200 µg da sequência de peptídeos 58-81 de P2 emulsificada em 100 µl de adjuvante de Freund completo (AFC) foram injetados por via subcutânea, em quatro locais na região lombar. Para os controles, foi utilizado solução tamponada de fosfato (PBS), emulsionada em AFC desprovida da sequência 58-81 de peptídeos P2, injetada no mesmo local, na mesma quantidade e forma. Cada camundongo tratado com P2 recebeu 200 ng de toxina pertussis em 100 ?L de PBS intraperitonealmente (i.p.) nos dias 0 e 2 pós-imunização (p.i.). No grupo controle, volumes iguais de PBS e toxina pertussis foram administrados pela mesma via sem o peptídeo. Avaliações da motricidade foram realizadas diariamente até o 60º dia, além de análises funcionais e eletroneuromiográficas. Foram encontradas alterações exclusivamente eletrofisiológicas, desmielinizantes e axonais, em cerca de dois terços dos camundongos. Sendo o camundongo SJL/J considerado o camundongo mais susceptível para a provocação de NAE, os achados do presente estudo indicam a limitação do modelo: ausência de alterações motoras detectáveis clinicamente, ocorrendo distúrbios eletrofisiológicos em apenas parte dos animais. O melhor modelo de NAE continua sendo o provocado no rato Lewis por proteína da mielina periférica bovina. É desejável que se continue buscando modelo experimental de NAE em camundongos, tendo em vista que essa espécie animal é a mais bem estudada na Biologia animal e, por essa razão, dela haver extensa variedade de imunobiológicos disponíveis para estudo da patogenia e fisiopatologia de doenças auto-imunes. / Experimental autoimmune neurits (EAN) is a monophasic demyelinating disease of the peripheral nervous system (PNS). EAN is considered to be the experimental model for Guillain-Barré syndrome (GBS). EAN can be induced in genetically susceptible mice using peripheral myelin components as immunogens: peripheral nerve myelin proteins P0 or P2; peptides sequences of those proteins considered neuritogenic, or the adoptive transfer of TCD4+ lymphocytes from previously immunized mice. In the present study non-pregnant female SJL/J mice aged 8-12 weeks weighint 17-20 g where used. The experimental group was treated as follows. Peptides sequence of P2 (200 µg) emulsified in complete Freund adjuvant (CFA) (100 µl) injected in four sites at the lumbar paravertebral region s.c. Controls were injected in the same sites with equal quantities of phosphate buffer solution emulsified in CFA without the peptides sequence. Each mouse treated with P2 was also treated with 200 ng pertussis toxin in 100 ?L PBS i.p. at the days 0 and 2 post-immunisation. Controls were injected i.p. with equal volumes of PBS and pertussis toxin free of the peptides sequence. Motor strength, posture and coordination were evaluated daily until the 60th day postinoculation besides eletroneuromyographic (EMG) evaluation on the 10th and 30thy days of some mice. No clinical disturbances were observed and in two thirds of the animals demyelinating and axonal features were detected at the EMG. SJL/J mice are considered the most susceptible mouse strain for NAE induction but the findings of the present study indicates the limitations of the model and its reproducibility. The best NAE model is yet the obtained in Lewis rat. It is important to look for a mouse model of EAN because this animal species is the most studied in the animal Biology. The extensive variety of immunobiologic products from mice allows performing studies on the pathogeny or physiopathology of autoimmune diseases more easily.