Identification of the complement C4d fragment in peritubular capillaries as a specific marker for antibody mediated rejection in renal transplantation revealed the critical role of antibodies in graft survival. In this thesis, I document the design and findings of studies performed to investigate the clinical impact of anti-HLA antibodies present before and/or after transplantation. Over time, the detection techniques for anti-HLA antibodies has evolved from the less sensitive complement-dependent lymphocytotoxicity (CDC) crossmatching (XM) to more sensitive solid phase assays such as Luminex®. Studies have been conducted to compare the predictive value of different antibody detection techniques. The first result chapter presents antibody specificity in positive CDC B-cell crossmatch (BXM), analysed with highly specific Luminex® assays. The study also investigates the predictive value of BXM in the general transplant population. I found that donor-specific anti-HLA antibodies (DSA) are only present in one third of positive BXM and are associated with poor outcomes. The novel finding is that >80% of the DSA detected by BXM are complement-fixing IgG₁ and IgG₃ subclasses. Transplant glomerulopathy (TG) is type of chronic renal graft rejection. The pathogenesis of TG is unclear. In the second result chapter, I report risk factors and involvement of anti-HLA antibodies in the development of TG. This study shows that glomerular rejection, delayed graft function, HLA presensitization and DSA have a univariate effect on TG development. Multivariate analysis revealed that DSA are an independent predictor of TG, after adjustment for other risk factors. I have further investigated the role of BXM in a unique, well-matched, highly sensitized patient group transplanted under the national renal exchange programme. I compared Luminex® antibody analysis with BXM in predicting transplant outcomes. In highly sensitized patients, DSA are found in two thirds of positive BXM. In univariate analyses, BXM is associated with humoral rejection whereas DSA defined by Luminex® are associated with total and all rejection types. The major finding is that, by multivariate analysis, DSA defined by Luminex® are an independent predictor of total and humoral rejection, but BXM are not. These interesting findings are reported in the third result chapter. Studies reported in this thesis define the clinical significance of anti-HLA antibodies in renal transplant outcomes. Method comparison studies provide useful information on antibody specificity and their impact on graft survival. Collectively, a better understanding of alloantibodies associated with graft rejection and limitation of antibody detection methods may facilitate donor selection and choice of immunosuppressants, and consequently improve transplant outcomes. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1379925 / Thesis (Ph.D.) - University of Adelaide, School of Medicine, 2010

Introdução: Testes de histocompatibilidade são indispensáveis para viabilizar o transplante renal. A prova cruzada por citotoxicidade dependente de complemento (CDC) tem sido a técnica padrão para avaliar risco imunológico pré-transplante, no entanto, a prova cruzada por citometria de fluxo (FCXM) possui benefícios adicionais, como maior sensibilidade e análise semi-quantitativa através do Median Channel Shift (MCS). Objetivo: Definir pontos de corte de MCS baseado em correlação inter-técnicas e desfechos clínicos pós-transplante. Método: Estudo retrospectivo com pacientes candidatos a transplante renal no Hospital de Clínicas de Porto Alegre, entre janeiro/2016-agosto/2017. Foram avaliadas 1705 provas cruzadas e 221 pacientes submetidos ao transplante. Resultados: A FCXM, relacionada ao CDC, apresentou sensibilidade=87%(FCXM-T) e 90%(FCXM-B), e VPN=98% para ambos. FCXM-B apresentou especificidade=43%, relacionada aos casos CDC-/FCXMB+. FCXM-T e -B detectaram 53% e 76% dos casos de DSA≥5001 (Donor Specific Antibody). MCS apresentou desempenho satisfatório em detectar CDC+ (AUC/IC): MCST=0,909(0,886-0,933) e MCSB=0,775(0,724-0,826). Pontos de corte de MCST=245 e MCSB=282 apresentaram melhor predição de CDC+. Não houve diferença na função do enxerto de pacientes transplantados com FCXM+. Apenas 30% das FCXM+ estiveram diretamente relacionadas com DSA pré-tx. No entanto, episódios de rejeição foram mais frequentes no grupo FCXM+vs.FCXM- (95%vs.86%, p=0,04). Conclusão: É possível calibrar o MCS baseado no CDC+, no entanto, significa um risco em termos da não detecção de anticorpos de baixo título. A FCXM+, em curto prazo, não deve ser por si só um fator impeditivo para o transplante. A análise conjunta do MCS e DSA parece ser uma boa ferramenta de seleção dos receptores renais. / Introduction: Histocompatibility tests are indispensable for enable the renal transplantation. Crossmatching tests for complement dependent cytotoxicity (CDC) has been a standard technique for assess pre-transplant immunological risk, however, the flow cytometry crossmatching test (FCXM) has additional benefits, such as increased sensitivity and semi-quantitative analysis through the Median Channel Shift (MCS). Objective: Define MCS cutoff values based on inter-technical correlation and post-transplant clinical outcomes. Methods: A retrospective study with renal transplant candidates at the Hospital de Clínicas of Porto Alegre, between January/2016-August/2017. A total of 1705 crossmatching and 221 patients submitted to transplantation were evaluated. Results: The FCXM, related to CDC, resulted in sensitivity=87% (FCXM-T) and 90% (FCXM-B), and NPV=98%, for both. FCXM-B resulted in specificity=43%, related to cases CDC-/FCXMB+. FCXM-T and -B detected 53% and 76% of cases of DSA≥5001 (Donor Specific Antibody). The MCS showed satisfactory performance in detecting CDC + (AUC/IC): MCST=0.909(0.886-0.933) and MCSB=0.775(0.724-0.826). Cutoff values of MCST=245 and MCSB=282 showed better prediction of CDC+. There was no difference in the graft function of patients transplanted with FCXM+. Only 30% of FCXM + were directly related to pre-tx DSA. However, rejection episodes were more frequent in the group FCXM+vs.FCXM- (95%vs.86%, p=0,04). Conclusion: it is possible to calibrate MCS based on CDC +, however, that means a risk in terms as to the non-detection of low-titre antibodies. The FCXM+, in the short term, should not be by itself an impediment to transplantation. Joint analysis of MCS and DSA seems to be a good tool for selection of renal receptors.

Major challenges in the management of blood supply chain are related to the shortage and wastage of the blood products. Given the perishability characteristics of blood which can be stored up to a limited number of days, if hospitals and blood centers keep an excessive number of blood units on inventory, wastages may occur. On the other hand, if sufficient number of blood units are not stored on inventory, shortages of this resource may cause the cancellations of important activities and increase the fatality rates at hospitals. Three mathematical models have been developed with the goal to improve the efficiency of blood related activities at blood centers and hospitals. The first model uses an integer programming (IP) approach to identify the optimal order levels that minimizes the total cost, shortage and wastage levels of blood products at a hospital within a specified planning horizon. The IP model explicitly considers the age of blood inventory, uncertain demand, the demand for two types of patients and crossmatch-to-transfusion ratio. The second model formulates the different shortage and inventory distribution strategies of a blood center supplying blood products to multiple hospitals. The third model develops a vehicle routing problem for blood centers to minimize the daily distance travelled by bloodmobiles during the blood collection process. Optimal routing for each bloodmobiles is identified using CPLEX solver, branch \& bound and column generation algorithms and their solution times are compared.

L’objectif de cette étude est de déterminer l’importance clinique de l’antigène érythrocytaire canin Dal, en investiguant sa prévalence, son mode d’héritabilité et son immunogénicité. Un total de 1230 chiens a été recruté à travers l’Amérique du Nord et typés pour le Dal en utilisant des allo-anticorps polyclonaux et une technique sur colonne de gel. Des individus Dal-négatifs ont été identifiés chez les Dalmatiens (n=15/128), Doberman Pinschers (n=183/432), Shih Tzus (n=12/21), chiens de races croisées (3/122), Beagles (2/100), Lhasa Apso (1/3) et Bichon Frisé (1/6). Six donneurs de sang Dal-négatifs ont été identifiés, dont 5 Doberman Pinschers (1/228 donneurs d’une autre race). Tous les autres chiens testés étaient Dal-positifs (n=418). La rareté du sang Dal-négatif place les chiens Dal-négatifs à risque d’incompatibilité transfusionnelle lors de transfusions multiples. Cette étude est la première à identifier des individus Dal-négatifs chez des chiens de race autre que Dalmatien et à établir le mode d’héritabilité du Dal, soit autosomal dominant. Par la suite, 2 Beagles Dal-négatifs ont été sensibilisés spécifiquement pour le Dal en recevant une transfusion Dal-positif. Suivant la sensibilisation, des allo-anticorps anti-Dal ont été détectés à partir du 4ième jour post-transfusion et sont demeurés détectables jusqu’à 2 ans post-transfusion. Les titres d’agglutination maximaux (1:64 et 1:1024) ont été atteints 2 et 1 mois post-transfusion chez le chien #1 et le chien #2, respectivement. Cette étude a confirmé l’immunogénicité du Dal tout en ayant généré une quantité considérable d’allo-anticorps anti-Dal permettant de futurs typages sanguins Dal. / The purpose of this study was to determine the clinical importance of the Dal canine erythrocyte antigen by investigating its prevalence, its mode of inheritance and its immunogenicity. A total of 1230 dogs recruited from North America were blood typed for Dal applying a gel column technique using polyclonal canine anti-Dal sera. Dal-negative dogs were identified mostly in Dalmatians (15/128), Dobermans Pinschers (183/432) and Shih Tzus (12/21), and sporadically in mixed breed dogs (3/122), Beagles (2/100), Lhasa Apso (1/6) and Bichon Frise (1/3). All other dogs tested were Dal-positive (n= 418). Six Dal-negative blood donors were found, including 5 Doberman Pinschers (1/228 non-Dalmatian and non-Doberman Pinscher blood donors). The scarcity of Dal-negative blood donors puts Dal-negative patient at higher risk of transfusion incompatibility if requiring multiple blood transfusions. This study was the first to identify Dal-negative dogs in other breeds than Dalmatians and to establish an autosomal dominant mode of inheritance of the Dal-positive phenotype. Secondly, 2 Dal-negative healthy research Beagles were sensitized specifically for Dal with a Dal-positive packed red blood cell transfusion. Following sensitization, anti-Dal alloantibodies were detected as early as 4 days post-transfusion and remained detectable 2 years post-transfusion, with maximum agglutination titers (1:1024 and 1:64) reached respectively 1 and 2 months posttransfusion in dog #2 and dog #1. Our study confirmed the immunogenicity of the Dal and allowed banking of a considerable amount of polyclonal antisera for further Dal blood typing.

O maior consumo de concentrados de hemácias está relacionado a pacientes que enfrentam procedimentos cirúrgicos. A solicitação de reserva de concentrados de hemácias para cirurgia em quantidades muito além do necessário sobrecarrega a Agência Transfusional, configura desperdício de recursos humanos, danos ao erário e prejuízo ao paciente, haja vista que muitos hemocomponentes são reservados para cirurgias, mas poucos são utilizados. A dificuldade no transporte e armazenamento dos hemocomponentes em condições adequadas fora da Agência Transfusional é fato que agrava essa situação e aumenta o desperdício, pois muitos hemocomponentes são solicitados, não são utilizados e retornam ao Serviço de Hemoterapia sem condições de serem reintegrados ao estoque. Tendo em vista que o Hospital de Base do Distrito Federal é a unidade hospitalar com o maior quantitativo em solicitação de reservas de concentrados de hemácias, e por ser recomendável que cada Serviço de Hemoterapia desenvolva seu protocolo específico e personalizado, o objetivo desse estudo é criar um manual de reserva de concentrados de hemácias para procedimentos invasivos, com o quantitativo de hemocomponentes a serem reservados para cada tipo de cirurgia, visando promover o uso racional do sangue no referido hospital. Para isso foi realizado um levantamento dos dados de cirurgias realizadas no Hospital de Base do Distrito Federal nos meses de fevereiro a julho de 2015. Em cada cirurgia foi analisado se houve solicitação e utilização de reserva de hemocomponentes. Com os dados obtidos foi calculado o índice de pacientes transfundidos para cada tipo de cirurgia, sendo confeccionado o manual, que consiste em um quadro com a conduta hemoterápica a ser adotada em cada tipo de cirurgia, se nenhuma, ou realização de tipagem e pesquisa de anticorpos irregulares, ou realização de prova de compatibilidade e reserva de concentrado de hemácias. Foi calculada a quantia aproximada de recursos com insumos que seria economizada caso fosse adotada a conduta sugerida no ano estudado. Para que o manual seja efetivamente aplicado tanto no momento de realizar a solicitação da reserva quanto no momento de preparar a reserva, deve haver uma sistemática de implantação do manual no ambiente hospitalar, com orientações quanto ao correto preenchimento do tipo de cirurgia no mapa cirúrgico e na requisição de reserva ao Banco de sangue. É importante a reavaliação periódica e comparação das solicitações de reservas de concentrados de hemácias para cirurgias eletivas com o cenário do ano anterior. O sucesso na implementação deste manual depende da compreensão e colaboração de uma equipe multidisciplinar de cirurgiões, anestesistas e colaboradores da Agência Transfusional. / Optimizing blood ordering and transfusion has been largely discussed because of patient\'s safety and money constraints. The highest use of red blood cells in a hospital is related to surgical procedures. The preoperative blood order in quantities much higher than necessary, overloads the Blood bank, which configures wasted human resources, wasted public resources and can cause injury to the patient. In most hospitals many blood components are reserved for surgeries, but few are used. The difficulty in transporting and storing the blood components in suitable conditions outside the Blood bank aggravates this situation and increases the costs. Many blood components are requested but not used and return to the blood transfusion service without conditions to be reintegrated into the stock. Considering that Hospital de Base of the Federal District Brazil is the one with the highest quantity of preoperative crossmatching orders in our state, the purpose of this study was to create a maximum blood ordering schedule (MBOS) for elective surgeries. MBOS has been established since 1977 and should be based on recommendation that each hospital may develop for its specific needs. This MBOS should recommend the maximum packed red blood cell quantity to be reserved for each type of surgery, aiming to promote the rational use of blood in the hospitals. For that, a survey of the data of surgeries performed at the Hospital de Base was carried out from February to July 2015. For each surgery, we analyzed if there was a request and use of a packed red blood cell. With the data obtained, the index of patients transfused for each type of surgery was calculated, and the manual was elaborated, consisting of a chart with hemotherapy decision to be adopted in each type of surgery. The manual included 3 types of recommendations for blood bank staff: none, type and screen only, or crossmatch units of packed red blood cells. The approximate amount of resources that would be saved if the suggested strategy were adopted in 2015 were also calculated. The idea is to have a systematic implementation of the manual in the hospital considering the moment of ordering blood products and the moment of adopting the strategy proposed at the blood bank. Some improvements are needed such as guidelines with suggestions including the complete and accurate filling of the surgical map (exact type of surgery) and implementation of a better blood ordering system with more information about patients and surgeries. This kind of manual most be reviewed periodically since surgical procedures can change over time with new techniques been included in the therapeutic strategies. The success in implementing this manual depends on the consent and collaboration of a multidisciplinary team including surgeons, anesthesiologists, and blood bank staff.

O maior consumo de concentrados de hemácias está relacionado a pacientes que enfrentam procedimentos cirúrgicos. A solicitação de reserva de concentrados de hemácias para cirurgia em quantidades muito além do necessário sobrecarrega a Agência Transfusional, configura desperdício de recursos humanos, danos ao erário e prejuízo ao paciente, haja vista que muitos hemocomponentes são reservados para cirurgias, mas poucos são utilizados. A dificuldade no transporte e armazenamento dos hemocomponentes em condições adequadas fora da Agência Transfusional é fato que agrava essa situação e aumenta o desperdício, pois muitos hemocomponentes são solicitados, não são utilizados e retornam ao Serviço de Hemoterapia sem condições de serem reintegrados ao estoque. Tendo em vista que o Hospital de Base do Distrito Federal é a unidade hospitalar com o maior quantitativo em solicitação de reservas de concentrados de hemácias, e por ser recomendável que cada Serviço de Hemoterapia desenvolva seu protocolo específico e personalizado, o objetivo desse estudo é criar um manual de reserva de concentrados de hemácias para procedimentos invasivos, com o quantitativo de hemocomponentes a serem reservados para cada tipo de cirurgia, visando promover o uso racional do sangue no referido hospital. Para isso foi realizado um levantamento dos dados de cirurgias realizadas no Hospital de Base do Distrito Federal nos meses de fevereiro a julho de 2015. Em cada cirurgia foi analisado se houve solicitação e utilização de reserva de hemocomponentes. Com os dados obtidos foi calculado o índice de pacientes transfundidos para cada tipo de cirurgia, sendo confeccionado o manual, que consiste em um quadro com a conduta hemoterápica a ser adotada em cada tipo de cirurgia, se nenhuma, ou realização de tipagem e pesquisa de anticorpos irregulares, ou realização de prova de compatibilidade e reserva de concentrado de hemácias. Foi calculada a quantia aproximada de recursos com insumos que seria economizada caso fosse adotada a conduta sugerida no ano estudado. Para que o manual seja efetivamente aplicado tanto no momento de realizar a solicitação da reserva quanto no momento de preparar a reserva, deve haver uma sistemática de implantação do manual no ambiente hospitalar, com orientações quanto ao correto preenchimento do tipo de cirurgia no mapa cirúrgico e na requisição de reserva ao Banco de sangue. É importante a reavaliação periódica e comparação das solicitações de reservas de concentrados de hemácias para cirurgias eletivas com o cenário do ano anterior. O sucesso na implementação deste manual depende da compreensão e colaboração de uma equipe multidisciplinar de cirurgiões, anestesistas e colaboradores da Agência Transfusional. / Optimizing blood ordering and transfusion has been largely discussed because of patient\'s safety and money constraints. The highest use of red blood cells in a hospital is related to surgical procedures. The preoperative blood order in quantities much higher than necessary, overloads the Blood bank, which configures wasted human resources, wasted public resources and can cause injury to the patient. In most hospitals many blood components are reserved for surgeries, but few are used. The difficulty in transporting and storing the blood components in suitable conditions outside the Blood bank aggravates this situation and increases the costs. Many blood components are requested but not used and return to the blood transfusion service without conditions to be reintegrated into the stock. Considering that Hospital de Base of the Federal District Brazil is the one with the highest quantity of preoperative crossmatching orders in our state, the purpose of this study was to create a maximum blood ordering schedule (MBOS) for elective surgeries. MBOS has been established since 1977 and should be based on recommendation that each hospital may develop for its specific needs. This MBOS should recommend the maximum packed red blood cell quantity to be reserved for each type of surgery, aiming to promote the rational use of blood in the hospitals. For that, a survey of the data of surgeries performed at the Hospital de Base was carried out from February to July 2015. For each surgery, we analyzed if there was a request and use of a packed red blood cell. With the data obtained, the index of patients transfused for each type of surgery was calculated, and the manual was elaborated, consisting of a chart with hemotherapy decision to be adopted in each type of surgery. The manual included 3 types of recommendations for blood bank staff: none, type and screen only, or crossmatch units of packed red blood cells. The approximate amount of resources that would be saved if the suggested strategy were adopted in 2015 were also calculated. The idea is to have a systematic implementation of the manual in the hospital considering the moment of ordering blood products and the moment of adopting the strategy proposed at the blood bank. Some improvements are needed such as guidelines with suggestions including the complete and accurate filling of the surgical map (exact type of surgery) and implementation of a better blood ordering system with more information about patients and surgeries. This kind of manual most be reviewed periodically since surgical procedures can change over time with new techniques been included in the therapeutic strategies. The success in implementing this manual depends on the consent and collaboration of a multidisciplinary team including surgeons, anesthesiologists, and blood bank staff.

La médecine transfusionnelle féline a connu une croissance exponentielle au cours des dix dernières années. La découverte du système de groupes sanguins AB et la meilleure compréhension des mécanismes d’incompatibilité donneur-receveur, ainsi que le développement de systèmes de collecte adaptés au chat et de techniques de typage sanguin au chevet du patient ont permis d’améliorer la sécurité des transfusions. Notre travail s’est intégré dans cette volonté d’optimiser la sécurité des transfusions sanguines chez le chat en se concentrant sur deux aspects différents : le prélèvement de sang et les antigènes érythrocytaires à l’origine d’incompatibilités donneur-receveur non expliquées par le système AB. Dans un premier temps, un système de collecte de sang adapté au chat a été fabriqué afin de permettre un prélèvement fermé et autoriser le stockage des produits sanguins. Ce système a été comparé à un système ouvert composé de seringues. Le système fermé apparaît adapté au prélèvement de sang car aucune différence significative n’a été enregistrée dans les paramètres vitaux des donneurs après le prélèvement, le succès du prélèvement, ou la qualité du produit sanguin en termes de contamination bactérienne et d’hémolyse, entre les deux systèmes. Le net avantage du système fermé est qu’il assure un temps de prélèvement plus rapide que le système ouvert. Dans un second temps, en réalisant des tests de compatibilité chez 258 chats de type A, nous avons montré que la probabilité de détecter des incompatibilités entre deux chats de groupe A sélectionnés aléatoirement était de 3.9 %, et que 7 % des chats de groupe A présentaient des allo-anticorps naturels extérieurs au système AB. Sept des 18 allo-anticorps naturels détectés ont été utilisés comme réactifs lors d’un typage sanguin extensif. Les analyses sur l’accord des résultats du typage obtenus avec les différents réactifs ont permis d’identifier cinq nouveaux antigènes érythrocytaires félins différents, nommés FEA 1 à FEA 5 (pour feline erythrocyte antigen), dont l’hérédité, la prévalence, la distribution géographique et par race, ainsi que l’immunogénicité restent encore à déterminer. / Feline transfusion medicine has grown exponentially over the past decade. The discovery of the AB blood group system and the better understanding of the mechanisms of donor-receiver incompatibility, as well as the development of cat-friendly collection systems and bedside blood typing techniques have improved transfusion safety. Our work has been part of this effort to optimize the safety of blood transfusions in cats by focusing on two different aspects: blood collection and red blood cell antigens that cause donor-recipient incompatibilities unexplained by the AB system. First, a blood collection system adapted to the cat was manufactured to allow collection in a closed-system and storage of blood products. This system was compared to an open system consisting of syringes. The closed system appeared well-adapted for feline blood collection because no significant difference was found in the vital parameters of the donors after collection, the success of the collection, or the quality of the blood product in terms of bacterial contamination and hemolysis. The distinct advantage of the closed system was that it provided a shorter duration of collection than the open system. Secondly, based on the systematic crossmatches of 258 cats, we showed that the probability of detecting incompatibilities by randomly crossmatching two type A cats was 3.9 %, which resulted in at least 7 % of type A cats having naturally occurring alloantibodies outside the AB blood group system. Seven of the 18 detected naturally occurring alloantibodies were used as reagents in an extensive blood typing. Comparison of the results obtained from this extensive blood typing supports the existence of five, presumably different, new feline erythrocyte antigens, named FEA 1 to FEA 5, whose mode of inheritance, geographical and breed distribution, frequency and immunogenicity have yet to be determined.