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1.
Int J Immunogenet ; 50 Suppl 2: 3-63, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37919251

RESUMO

Solid organ transplantation represents the best (and in many cases only) treatment option for patients with end-stage organ failure. The effectiveness and functioning life of these transplants has improved each decade due to surgical and clinical advances, and accurate histocompatibility assessment. Patient exposure to alloantigen from another individual is a common occurrence and takes place through pregnancies, blood transfusions or previous transplantation. Such exposure to alloantigen's can lead to the formation of circulating alloreactive antibodies which can be deleterious to solid organ transplant outcome. The purpose of these guidelines is to update to the previous BSHI/BTS guidelines 2016 on the relevance, assessment, and management of alloantibodies within solid organ transplantation.


Assuntos
Isoanticorpos , Transplante de Órgãos , Humanos , Transplante de Órgãos/efeitos adversos , Teste de Histocompatibilidade , Isoantígenos , Reino Unido , Antígenos HLA , Rejeição de Enxerto
2.
Int J Immunogenet ; 48(5): 385-402, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34346180

RESUMO

The avoidance of antibody-mediated rejection (AMR) attributed to human leucocyte antigen (HLA) antibody incompatibility remains an essential function of clinical Histocompatibility and Immunogenetics (H&I) laboratories who are supporting solid organ transplantation. Developments in HLA antibody identification assays over the past thirty years have greatly reduced unexpected positive cellular crossmatches and improved solid organ transplant outcomes. For sensitized patients, the decision to register unacceptable HLA antigen mismatches is often heavily influenced by results from solid phase antibody assays, particularly the Luminex® Single Antigen Bead (SAB) assays, although the clinical relevance of antibodies identified solely by these assays remains unclear. As such, the identification of non-clinically relevant antibodies may proportionally increase the number of unacceptable transplant mismatches registered, with an associated increase in waiting time for a compatible organ. We reflect on the clinical relevance of antibodies identified solely by the Luminex SAB® assays and consider whether the application of additional assays and/or tools could further develop our ability to define the clinical relevance of antibodies identified in patient sera. Improvements in this area would assist equity of access to a compatible transplant for highly sensitized patients awaiting a solid organ transplant.


Assuntos
Antígenos HLA , Transplante de Órgãos , Anticorpos , Rejeição de Enxerto , Antígenos HLA/genética , Histocompatibilidade , Teste de Histocompatibilidade , Humanos , Isoanticorpos
3.
Blood ; 137(3): 310-322, 2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33475737

RESUMO

Platelet transfusion refractoriness results in adverse outcomes and increased health care costs. Managing refractoriness resulting from HLA alloimmunization necessitates the use of HLA antigen-matched platelets but requires a large platelet donor pool and does not guarantee full matching. We report the first randomized, double-blind, noninferiority, crossover trial comparing HLA epitope-matched (HEM) platelets with HLA standard antigen-matched (HSM) platelet transfusions. Alloimmunized, platelet-refractory, thrombocytopenic patients with aplastic anemia, myelodysplastic syndrome, or acute myeloid leukemia were eligible. HEM platelets were selected using HLAMatchMaker epitope (specifically eplet) matching. Patients received up to 8 prophylactic HEM and HSM transfusions provided in random order. The primary outcome was 1-hour posttransfusion platelet count increment (PCI). Forty-nine patients were randomized at 14 UK hospitals. For intention to treat, numbers of evaluable transfusions were 107 and 112 for HEM and HSM methods, respectively. Unadjusted mean PCIs for HEM and HSM methods were 23.9 (standard deviation [SD], 15) and 23.5 (SD, 14.1), respectively (adjusted mean difference, -0.1; 95% confidence interval [CI], -2.9 to 2.8). Because the lower limit of the 95% CI was not greater than the predefined noninferiority limit, the HEM approach was declared noninferior to the HSM approach. There were no differences in secondary outcomes of platelet counts, transfusion requirements, and bleeding events. Adequate 1-hour PCI was more frequently observed, with a mean number of 3.2 epitope mismatches, compared with 5.5 epitope mismatches for inadequate 1-hour increments. For every additional epitope mismatch, the likelihood of an adequate PCI decreased by 15%. Epitope-matched platelets should be considered to support HLA alloimmunized patients. This trial was registered at www.isrctn.com as #ISRCTN23996532.


Assuntos
Plaquetas/imunologia , Epitopos/imunologia , Antígenos HLA/imunologia , Teste de Histocompatibilidade , Transfusão de Plaquetas , Adolescente , Adulto , Idoso , Sequência de Aminoácidos , Especificidade de Anticorpos/imunologia , Estudos Cross-Over , Epitopos/química , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
4.
Transfus Med ; 30(1): 23-29, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31209973

RESUMO

AIMS/OBJECTIVES: To explore the impact of Human Leucocyte Antigen (HLA)-A and B epitope-matched platelets on the outcome of platelet transfusions in alloimmunised patients with aplastic anaemia (AA). The relevance of HLA-C epitope mismatches was also investigated. BACKGROUND: Patients who become immunologically refractory (IR) to random platelet transfusions can experience an adequate rise in platelet count through the provision of HLA-compatible platelets using an antigen-matching algorithm. This approach has been shown to be effective in patients with a low calculated reaction frequency, but it is not always successful in highly sensitised patients. The use of HLA epitopes-selected platelets has been suggested as an alternative to the antigen matching approach. METHODS: The effect of HLA epitope matching (both Eplets and Triplets) on the outcome of platelet transfusion was analysed in 37 highly immunised AA patients previously transfused with HLA-A and B antigen-matched platelets. Epitope matching was determined using the HLAMatchmaker programme. The outcome of the transfusions was assessed by the platelet count increments (PCIs) obtained 1 and 24 hours post-transfusions. RESULTS: HLA-A and B epitope matching was equivalent to HLA antigen matching in raising platelet counts. There was no significant difference in PCI when HLA-C epitope mismatches were considered. In addition, transfusions with fewer than two antigen mismatches resulted in significantly higher PCIs compared to transfusions with more than two antigen mismatches. CONCLUSIONS: HLA epitope-matched platelet provision may represent a clinically effective transfusion strategy for patients IR to random platelet transfusions. Further prospective studies are required.


Assuntos
Anemia Aplástica , Epitopos , Antígenos HLA-A , Antígenos HLA-B , Isoanticorpos , Transfusão de Plaquetas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anemia Aplástica/sangue , Anemia Aplástica/imunologia , Anemia Aplástica/terapia , Criança , Epitopos/sangue , Epitopos/imunologia , Feminino , Antígenos HLA-A/sangue , Antígenos HLA-A/imunologia , Antígenos HLA-B/sangue , Antígenos HLA-B/imunologia , Humanos , Isoanticorpos/biossíntese , Isoanticorpos/imunologia , Masculino , Pessoa de Meia-Idade
5.
Int J Health Care Qual Assur ; 28(1): 75-81, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26308404

RESUMO

PURPOSE: The purpose of this paper is to measure family member satisfaction with the care provided in an Australian private intensive care unit (ICU) at two time points separated by two years. The study was part of a quality improvement process for ICU, and was designed with reference to the revised Australian Commission on Safety and Quality in Health care. DESIGN/METHODOLOGY/APPROACH: This prospective study involved family members of patients admitted in ICU in February 2011 and February 2013. All patients admitted to during the study month were eligible. Questionnaire addressed staff competence, treatment of family, communication, environment and overall satisfaction, using a Likert scale. There was one free text question. The first survey was done by handing the survey package to the next of kin at the time of discharge while the second involved mailing a survey package within a week of discharge from ICU. Quantitative analysis was based on ten Likert items and qualitative analysis based on the free text question. FINDINGS: The response rate was 53 percent (54/102) in 2013 (mailed) compared to 44 percent (44/100) in 2011 (hand delivered). The results from second (2013) survey showed statistically significant improvement in satisfaction associated with nursing and medical competency. Other areas with improvement were the relative's waiting room and visiting hours. The area lacking improvement was ease of finding ICU the hospital. It confirmed that families were satisfied with the care provided and highlighted areas for improvement. The results indicated high satisfaction overall, especially with the hospital staff competency and the overall care quality their relative received. Though most responses also indicated satisfaction with communication and support services, these areas did not perform as well. ORIGINALITY/VALUE: This study provided a simple and effective mechanism to monitor consumer satisfaction with ICU.


Assuntos
Família/psicologia , Unidades de Terapia Intensiva/organização & administração , Assistência ao Paciente , Satisfação do Paciente , Melhoria de Qualidade/organização & administração , Austrália , Competência Clínica , Comunicação , Meio Ambiente , Feminino , Humanos , Unidades de Terapia Intensiva/normas , Masculino , Estudos Prospectivos
6.
J Clin Pathol ; 63(3): 194-8, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20203219

RESUMO

Haematopoietic stem cell transplantation (HSCT) is now viewed as an effective treatment modality for a wide and varied number of diseases including both malignant and non-malignant haematological diseases, bone marrow failures, inherited immunodeficiencies and congenital metabolic disorders. This review will discuss the immunogenetic factors that play an influential role in the successful outcome of HSCT, most importantly the human leucocyte antigens (HLAs). Advances in HLA typing techniques enabling the definition of HLA types at the allele level have made it possible to investigate the impact of mismatching at individual HLA loci on HSCT outcome. Such studies have informed the strategy used for selection of both related and unrelated donors. This strategy, including the histocompatibility and immunogenetics laboratory testing required, is discussed in the context of published data, guidelines and recommendations.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Teste de Histocompatibilidade/métodos , Seleção do Doador/métodos , Doença Enxerto-Hospedeiro/prevenção & controle , Humanos , Doadores de Tecidos , Coleta de Tecidos e Órgãos/métodos
7.
Hematology ; 12(5): 461-9, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17852461

RESUMO

Transfusion related acute lung injury (TRALI) is one of the complications of blood transfusion and can result in major morbidity or mortality. The diagnosis depends upon the application of strict clinical criteria defining acute lung injury (ALI) and a temporal relationship to blood transfusion. We present the clinical and immunogenetic findings of 96 suspected TRALI cases investigated between 1996 and 2004. During this time period the national haemovigilance scheme (UK) defined TRALI as a reaction occurring either during or within 24 h of blood transfusion. Using clinical, laboratory and post mortem evidence, 64/96 cases could be defined as TRALI in our series. Sensitive techniques were employed to screen for HLA class I, class II and granulocyte specific antibodies in donor serum. Donor derived antibodies were detected in 58/64 (90%) of cases. Recipient derived DNA or cells were not always available but incompatibility was confirmed by the presence of the cognate antigen on recipient leucocytes or by crossmatching in 47/64 (73%) of cases. Cases referred prior to 2001 were not tested for HLA class II antibodies. By applying strict clinical criteria and using sensitive techniques a white blood cell antibody mediated immunological pathophysiology can be implicated in the majority TRALI cases.


Assuntos
Síndrome do Desconforto Respiratório/diagnóstico , Síndrome do Desconforto Respiratório/etiologia , Reação Transfusional , Granulócitos/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Teste de Histocompatibilidade , Humanos , Isoanticorpos/sangue , Síndrome do Desconforto Respiratório/imunologia , Resultado do Tratamento
8.
Br J Haematol ; 134(1): 95-9, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16803574

RESUMO

The outcome of 81 adult aplastic anaemia patients who had successful cytogenetics at diagnosis and received immunosuppressive therapy was evaluated. Ten patients had an abnormal karyotype, six of which had a trisomy. Four of five evaluable patients with a trisomy responded. One patient with monosomy 7 achieved a complete response and later developed haemolytic paroxysmal nocturnal haemoglobinuria but no recurrence of monosomy 7. None of the patients with a non-numerical karyotypic abnormality responded. No significant differences in survival or later clonal disorders were observed between patients with a normal karyotype and those with an abnormal karyotype.


Assuntos
Anemia Aplástica/genética , Aberrações Cromossômicas , Adolescente , Adulto , Idoso , Anemia Aplástica/tratamento farmacológico , Anemia Aplástica/mortalidade , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Humanos , Imunossupressores/uso terapêutico , Cariotipagem , Masculino , Pessoa de Meia-Idade , Taxa de Sobrevida , Resultado do Tratamento , Trissomia
9.
Melanoma Res ; 14(6): 463-71, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15577316

RESUMO

Tumour cells are able to evade the immune system by using several 'escape mechanisms'. Downregulation of molecules involved in the processing and presentation of self-antigens has been reported. However, these adaptations have not been compared in metastases in different anatomical locations but derived from a single patient. We investigated three melanoma cell lines--MJT1 from the parietal lobe of the brain, MJT3 from the cerebellum and MJT5 from the left side of the neck--established from biopsies excised from a 45 year old female patient. Although human leukocyte antigen (HLA) class I was detected in all three cell lines by flow cytometry using an anti-HLA monomorphic antibody, further serological analysis demonstrated HLA B38 loss in all three cell lines, HLA B7 downregulation in MJT5 (skin metastases) and B7 loss in MJT3 and MJT1 (brain metastases) compared with the HLA type of the patient's normal autologous lymphocytes. Interferon-gamma (IFNgamma) treatment increased the expression of HLA class I and transporters associated with antigen processing 1 (TAP1) in all three cell lines. De novo HLA class II molecule expression was observed after IFNgamma treatment in MJT3 and MJT5. Western blot and reverse transcription-polymerase chain reaction results revealed heterogeneity of melanoma-associated antigen (MAA) expression in the cell lines: MJT3 cells expressed higher levels of MAAs than the other two cell lines. In conclusion, this study has demonstrated that three metastatic lesions from a single patient can have differential expression of molecules involved in antigen processing (TAP1) and presentation (HLA I and II), but that expression of these molecules is modulated by IFNgamma to a similar degree in all cell lines. In contrast, the downregulation of expression of specific MAAs between the three cell lines was unaffected by the addition of IFNgamma.


Assuntos
Apresentação de Antígeno , Neoplasias Encefálicas/metabolismo , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe I/genética , Melanoma/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias Cutâneas/metabolismo , Membro 2 da Subfamília B de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Antígenos de Neoplasias , Antineoplásicos/farmacologia , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/secundário , Feminino , Antígenos HLA-B/genética , Antígenos HLA-B/metabolismo , Antígeno HLA-B38 , Antígeno HLA-B7/genética , Antígeno HLA-B7/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Interferon gama/farmacologia , Linfócitos/metabolismo , Melanoma/imunologia , Melanoma/secundário , Antígenos Específicos de Melanoma , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , RNA Mensageiro/metabolismo , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/secundário , Células Tumorais Cultivadas
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