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Abstract(s)
A transfusão de componentes de sangue é hoje uma terapêutica de suporte essencial para o tratamento e apoio em muitas situações clínicas e cirúrgicas. No entanto, a transferência de leucócitos na transfusão de sangue homólogo pode estar associada ao risco de vários efeitos adversos, tais como a doença do enxerto contra o hospedeiro associada à transfusão (TA-GVHD), a aloimunização e as reacções transfusionais febris não-hemolíticas (FNHTRs).
Para a prevenção da TA-GVHD o método da gama irradiação é recomendado pela food and drug administration, american association of blood bank e pelo conselho da europa, mas esta tecnologia não previne a aloimunização nem a FNHTRs. Neste contexto, tem-se desenvolvido novas tecnologias para o tratamento de redução de patogénios (PRT), tais como o uso de riboflavina (vitamina B2) que quando exposto à luz ultravioleta modifica os ácidos nucleicos, inibindo a replicação de patogénios e dos leucócitos nos produtos de sangue.
Objectivo: Este estudo pretende comparar o efeito da gama irradiação e da inactivação pelo método PRT numa pool de leucócitos que represente a produção das pools de plaquetas no centro regional de sangue do porto.
Material e Método: Os linfócitos T foram isolados de quatro concentrados leucoresiduais obtidos do sistema automatizado Atreus® 3C (CaridianBCT, Bélgica), pelo método do ficoll-histopaque. Com os concentrados residuais constituiu-se uma hiperpool e subdividiu-se em três pools; uma pool irradiada com uma dose de 33Gy (Gammacell® 3000 Elite, MDS Nordion), outra pool para inactivar pelo método Mirasol® PRT system e outra pool para controlo (sem tratamento). De cada uma das pools foram retiradas amostras representativas e preparados três ensaios. Cada ensaio foi composto pelo controlo negativo, controlo positivo, amostra irradiada e inactivada. Cada ensaio foi submetido à estimulação com o phorbol myristate acetate, PMA (com excepção do controlo negativo) para posteriormente analisar a expressão do CD69 nos linfócitos T, por citometria de fluxo.
Resultados: A média de expressão do CD69 nos linfócitos T, CD3 positivos, nas amostras irradiadas foi de 6,72% e nas amostras inactivadas pelo método PRT foi de 0,29%. No controlo negativo, a média de expressão do CD69 foi de 1,12%, enquanto no controlo positivo foi de 96,54%.
Conclusão: Deste estudo podemos concluir que tanto as amostras gama irradiadas como as amostras inactivadas pelo método PRT diminuem muito significativamente a expressão do CD69
The transfusion of blood components is now an essential supportive therapy for the treatment and support in many medical and surgical situations. However, the transfer of leukocytes in transfusion of homologous blood may be associated with several risk of adverse effects such as transfusion associated - graft versus host disease (TA-GVHD), alloimmunization and febrile non-hemolytic transfusion reactions (FNHTR). For the prevention of TA-GVHD, gamma irradiation method is recommended by the food and drug administration, american association of blood bank and the council of europe, but this technology does not prevent alloimmunization nor FNHTR. In this context, new technologies has been developed to reduce pathogens treatment (PRT), such as the use of riboflavin (vitamin B2) that when exposed to ultraviolet light modifies the nucleic acids by inhibiting the replication of pathogens and leukocytes in blood products. Aims: This study compares the gamma irradiation with the inactivation method PRT in the inactivation of leukocytes in a pool, prepared in regional blood center in porto (Portugal) from automated atreus 3C. Materials and Methods: The T cells were obtained from concentrates leucoresiduais Atreus® 3C automated system (CaridianBCT, Belgium) and isolated by ficoll-histopaque method. One hiperpool was created with the four leucoresiduais concentrated and divided into three pools , the first got irradiated with 33Gy dose (Gammacell® 3000 Elite ®, MDS Nordion), the second with the method for inactivating Mirasol® PRT System and the third to control the process (no treatment). The samples were subjected to stimulation with phorbol myristate acetate, PMA (except the negative control), and measured the CD69 expression on T lymphocytes. Results: The average of CD69 on T-lymphocytes (não sei como se escreve) and CD3-positive of the irradiated sample was 6,72% whereas the inactivated samples by the PRT method was 0,29%. In negative control the average CD69 was 1,12% while the positive control was 96,54%. This study has shown that both the samples gamma irradiated and inactivated by PRT drastically decrease the CD69 expression. Conclusion: This study has shown that both the samples gamma irradiated and inactivated by PRT drastically decrease the CD69 expression.
The transfusion of blood components is now an essential supportive therapy for the treatment and support in many medical and surgical situations. However, the transfer of leukocytes in transfusion of homologous blood may be associated with several risk of adverse effects such as transfusion associated - graft versus host disease (TA-GVHD), alloimmunization and febrile non-hemolytic transfusion reactions (FNHTR). For the prevention of TA-GVHD, gamma irradiation method is recommended by the food and drug administration, american association of blood bank and the council of europe, but this technology does not prevent alloimmunization nor FNHTR. In this context, new technologies has been developed to reduce pathogens treatment (PRT), such as the use of riboflavin (vitamin B2) that when exposed to ultraviolet light modifies the nucleic acids by inhibiting the replication of pathogens and leukocytes in blood products. Aims: This study compares the gamma irradiation with the inactivation method PRT in the inactivation of leukocytes in a pool, prepared in regional blood center in porto (Portugal) from automated atreus 3C. Materials and Methods: The T cells were obtained from concentrates leucoresiduais Atreus® 3C automated system (CaridianBCT, Belgium) and isolated by ficoll-histopaque method. One hiperpool was created with the four leucoresiduais concentrated and divided into three pools , the first got irradiated with 33Gy dose (Gammacell® 3000 Elite ®, MDS Nordion), the second with the method for inactivating Mirasol® PRT System and the third to control the process (no treatment). The samples were subjected to stimulation with phorbol myristate acetate, PMA (except the negative control), and measured the CD69 expression on T lymphocytes. Results: The average of CD69 on T-lymphocytes (não sei como se escreve) and CD3-positive of the irradiated sample was 6,72% whereas the inactivated samples by the PRT method was 0,29%. In negative control the average CD69 was 1,12% while the positive control was 96,54%. This study has shown that both the samples gamma irradiated and inactivated by PRT drastically decrease the CD69 expression. Conclusion: This study has shown that both the samples gamma irradiated and inactivated by PRT drastically decrease the CD69 expression.