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Made available in DSpace on 2015-07-22T20:50:07Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-02-27 / Objetivos: O estudo teve como objetivo determinar a prevalência e a especificidade de anticorpos anti-HLA e a prevalência de anti-neutrófilos em doadoras de sangue brasileiras e avaliar o impacto da exclusão de doadoras multíparas positivas da doação de sangue. Métodos: Foram estudadas amostras de soro de 350 doadoras distribuídas em quatro grupos de acordo com o número de gestações que tiveram (50 nulíparas, 100 com uma gestação, 100 com duas gestações, e 100 multíparas). Para a pesquisa de anticorpos foi utilizada a metodologia do ELISA pelos kits LAT-M e LAT-1240 (One Lambda, Inc, EUA) que detectam e identificam anticorpos anti-HLA, classe I e II, respectivamente. Sessenta e cinco doadoras multíparas, com resultados positivos e negativos no ELISA também foram testadas pela metodologia do LABScreen (One Lambda, Inc, EUA) que fornece a especificidade de anticorpos anti-HLA. Além disso, foi utilizado o teste de Aglutinação de Granulócitos (GAT) e Imunofluorescência de Granulócitos (GIFT) para detectar anticorpos anti-neutrófilos específicos. Resultados: Oitenta doadoras das 350 mulheres estudadas (22,9%) foram positivas para anticorpos anti-HLA, sendo que 37% eram multíparas, 26% mulheres que tiveram duas gestações e 17% que tiveram uma gestação. Todas as amostras de doadoras nulíparas foram negativas para anti-HLA. A diferença de doadoras positivas em cada grupo foi estatisticamente significante na prevalência de anti-HLA entre o grupo de nulíparas e de doadoras que tiveram no mínimo uma gestação (p < 0,001). Os soros de doadoras positivas pelo teste LAT-M foram também testados pelo LAT-1240, e em sete casos os anticorpos não puderam ser identificados. Dezessete doadoras (28,3%), consideradas negativas pelo LAT-M, apresentaram resultados positivos pelo LABScreen. O GAT foi aplicado para investigação do soro de doadoras negativas para anti-HLA, sendo positivo em duas de 264 doadoras (0,8%). Entre as doadoras com GAT positivo uma entre 62 (1,6%) era multípara e uma doadora entre 71 (1,4%) teve duas gestações. O GIFT também foi aplicado para doadoras negativas para anti-HLA e apresentou positividade em quatro mulheres de 264 (1,5%), sendo que duas entre 62 (3,2%) eram multíparas e duas entre 71 (2,8%) tiveram duas gestações. Conclusões: Anticorpos anti-HLA são encontrados freqüentemente em plasma de doadoras de sangue brasileiras (22,9%), e se correlacionam estatisticamente com o maior número de gestações (p < 0,001), aumentando a porcentagem de positividade com o aumento do xvi número de gestações. Apesar de apresentar uma menor freqüência (1,9% do total de doadoras nos testes GAT e GIFT), os anticorpos anti-neutrófilos também são encontrados em doadoras, podendo este valor ser maior uma vez que as doadoras positivas para anti-HLA não foram testadas. O impacto da exclusão de doadoras multíparas da doação de sangue corresponde a 4% do total de doadores. Em conclusão, anticorpos anti-HLA e anti-neutrófilos estão presentes no plasma de doadoras brasileiras e constituem fator de risco para desencadear TRALI em receptores de sangue com antígenos correspondentes. / Purpose: The aim of this study were to determine the prevalence and the specificity of anti-HLA, class I and II, antibodies and the prevalence of anti-neutrophil antibodies in Brazilians female blood donors and to assess the impact of excluding the positive multiparous blood donors from the blood donation. Methods: Serum samples from 350 Brazilians female blood donors, distributed according to the number of previous pregnancy (50 nuliparous, 100 one pregnancy, 100 two pregnancies,100 multiparous), has been examined to detect and to identify anti-HLA, class I and II, antibodies by enzyme-linked immunosorbent assay (ELISA), by LAT-M and LAT-1240 Kits (ONE LAMBDA, INC, EUA). Sixty-five multiparous female blood donors, between positive and negative by LAT-M, were tested by flow cytometry, by LABScreen Kit (ONE LAMBDA, INC, EUA), that provide the specificity of anti-HLA antibodies. Furthermore, the Granulocyte Agglutination (GAT) and Granulocyte Immunofluorescence (GIFT) Test were used to detect specific anti-neutrophil antibodies. Results: Anti-HLA antibodies, class I and/or II, have been found in 80 of 350 female blood donors (22.9%), from whom 37% were multiparous donors, 26% woman with two previous pregnancies, and 17% woman with one previous pregnancy. All the nuliparous blood donors were negative to anti-HLA antibodies. The difference among positive female blood donors in pregnancy groups was significant statistically in prevalence between nuliparous group and woman with at least one previous pregnancy (p < 0.001). The serum of positive female blood donors by LAT-M test were also tested by LAT-1240 Test and in seven women the anti- HLA antibodies can not be identified. Seventeen female blood donors, that were considered negative by LAT-M, were positive for anti-HLA antibodies by LABScreen. The GAT was applied to investigate the serum of negative female blood donors to anti- HLA. Two women of 264 female blood donors (0.8%) were positive to anti-neutrophil, from whom 1.6% were multiparous (one of 62) and 1.4% were women with two previous pregnancies (one of 71). The GIFT was also applied to negative female blood donors to anti-HLA and the women were positive to anti-neutrophil in four of 264 female blood donors (1.5%), from whom two multiparous of 62 (3.2%) and two of 71 (2.8%) women with two previous pregnancy. Conclusion: Anti-HLA antibodies have often been found in plasma of Brazilian female blood donors (22.9%), and are statistically associated with the number of pregnancy (p < 0,001). The percentage of positive women increases with xviii the number of pregnancy. Although the anti-neutrophil antibodies had less prevalence (1.9% of all women tested by GAT and GIFT), they are found in female blood donors. This value can be higher because the positive women to anti-HLA antibodies were not tested. The impact to exclude the positive multiparous blood donors to the blood donate is 4% of all blood donors. In conclusion, anti-HLA and anti-neutrophil antibodies are found in plasma of Brazilian female blood donors and they are considered risk factor to trigger TRALI in blood receptors with cognate antigen. / TEDE / BV UNIFESP: Teses e dissertações

L’implantation valvulaire (mise en place d’une stent-valve percutanée), pulmonaire ou aortique, est une procédure récente en plein (et rapide) développement. Cette procédure prometteuse, possède plusieurs écueils parmi lesquels, l’altération du matériel implanté lors de son déploiement. L’implantation valvulaire dans les voies pulmonaires dilatées, est une autre limite de la procédure. Dans notre travail, nous avons étudié le traumatisme valvulaire lié au déploiement des prothèses. Ensuite, nous avons évalué un nouveau dispositif de réduction du calibre de la voie pulmonaire, afin d’en élargir les indications ultérieurement.Nous avons donc dans un premier temps comparé 2 types de stent-valves, l’un expansible par ballon et l’autre auto-expansible. La comparaison a porté sur l’occurrence de lésions valvulaires lors du sertissage et du déploiement de ces 2 types de prothèses. Nous avons pu montrer la présence de lésions des feuillets péricardiques de ces prothèses, induites par la compression des dispositifs. Par ailleurs, la présence de lésions histologiques plus marquées avec les valves expansibles par ballon, suggère aussi un rôle de l’expansion de ces prothèses dans la genèse des lésions valvulaires post-déploiement. Nous n’avons pas constaté d’altérations des propriétés mécaniques du tissu valvulaire induites par la compression et le déploiement des feuillets.Dans une autre partie de notre travail, nous avons mis au point un modèle d’élargissement de la voie pulmonaire, associé à la création d’une insuffisance pulmonaire sévère. Nous avons pu montrer que la réduction du calibre de la voie d’éjection pulmonaire était possible avec notre réducteur, par voie endovasculaire ou transventriculaire droite. Il n’a pas été observé de migration ou de fracture du stent de ces prothèses 2 mois après la procédure. Si le modèle d’élargissement de la voie pulmonaire est intéressant pour évaluer les réducteurs et la faisabilité de leur implantation, un suivit à plus long terme est nécessaire avant d’envisager une implantation chez l’homme. Enfin, l’altération des feuillets induite par le maniement des prothèses, est un phénomène à prendre en considération. Il nécessite, compte tenu de son impact potentiel sur la durabilité des prothèses, une investigation plus approfondie. / Percutaneous valve implantation (PVI) is a new with fast growing expansion procedure. Nevertheless, this promising technic has some reefs. Impairment of the implanted device at deployment is one of them. Valvular implantation in dilated right ventricular outflow tract (RVOT) is another limit of the procedure. In our work, we studied the valvular traumatism after prosthesis deployment. Subsequently, we evaluated a new device for RVOT size reduction, in order to widen PVI indications.Firstly, We compared 2 types of valved-stent (VS) (balloon expandable and self-expandable). We compared the occurrence of valvular leaflets injury after crimping and deployment of both types of prosthesis. We showed the occurrence of pericardial leaflet injuries, induced by devices crimping. Otherwise, the presence of sharp histologic lesions with balloon expandable VS, suggests a prosthesis expansion role, in genesis of valvular injuries, as well. We couldn’t show any impairment of valvular tissue mechanical properties after leaflets crimping and deployment. In another part of our work, experimental asymmetric enlargement of the RVOT with creation of severe pulmonary regurgitation, were performed in an ovine model. Size reduction of the enlarged RVOT and PVI were successfully achieved through an endovascular and right transventricular access. Valve function was satisfactory in all correctly implanted VS (one case of inversion). No migration or fractures of the size reducer or VS were seen before animal sacrifice, after 2 months follow-up. Since feasibility of RVOT enlargement and RVOT reduction has been demonstrated, a long-term study is necessary before considering a human implantation. At last but not least, deterioration on valvular leaflets after prosthesis handling is an effect to consider. Taking into account its potential impact on prosthesis durability, it requires further deep investigations.