The systematic use of evidence-based methodologies and technologies enhances shared decision-making in the 2018 International Consensus Conference on Patient Blood Management.

BACKGROUND AND OBJECTIVES: Patient Blood Management (PBM) aims to optimize the care of patients who might need a blood transfusion. The International Consensus Conference on PBM (ICC-PBM) aimed to develop evidence-based recommendations on three topics: preoperative anaemia, red blood cell transfusion thresholds and implementation of PBM programmes. This paper reports how evidence-based methodologies and technologies were used to enhance shared decision-making in formulating recommendations during the ICC-PBM. MATERIALS & METHODS: Systematic reviews on 17 PICO (Population, Intervention, Comparison, Outcomes) questions were conducted by a Scientific Committee (22 international topic experts and one methodologist) according to GRADE (Grades of Recommendation, Assessment, Development and Evaluation) methodology. Evidence-based recommendations were formulated using Consensus Development Conference methodology. RESULTS: We screened 17 607 references and included 145 studies. The overall certainty in the evidence of effect estimates was generally low or very low. During the ICC, plenary sessions (100-200 stakeholders from a range of clinical disciplines and community representatives) were followed by closed sessions where multidisciplinary decision-making panels (>50 experts and patient organizations) formulated recommendations. Two chairs (content-expert and methodologist) moderated each session and two rapporteurs documented the discussions. The Evidence-to-Decision template (GRADEpro software) was used as the central basis in the process of formulating recommendations. CONCLUSION: This ICC-PBM resulted in 10 clinical and 12 research recommendations supported by an international stakeholder group of experts in blood transfusion. Systematic, rigorous and transparent evidence-based methodology in a formal consensus format should be the new standard to evaluate (cost-) effectiveness of medical treatments, such as blood transfusion.

Programmes for the management of preoperative anaemia: audit in ten European hospitals within the PaBloE (Patient Blood Management in Europe) Working Group.

BACKGROUND AND OBJECTIVES: Preoperative anaemia is an independent risk factor for a higher morbidity and mortality, a longer hospitalization and increased perioperative transfusion rates. Managing preoperative anaemia is the first of three pillars of Patient Blood Management (PBM), a multidisciplinary concept to improve patient safety. While various studies provide medical information on (successful) anaemia treatment pathways, knowledge of organizational details of diagnosis and management of preoperative anaemia across Europe is scarce. MATERIALS AND METHODS: To gain information on various aspects of preoperative anaemia management including organization, financing, diagnostics and treatment, we conducted a survey (74 questions) in ten hospitals from seven European nations within the PaBloE (Patient Blood Management in Europe) working group covering the year 2016. RESULTS: Organization and activity in the field of preoperative anaemia management were heterogeneous in the participating hospitals. Almost all hospitals had pathways for managing preoperative anaemia in place, however, only two nations had national guidelines. In six of the ten participating hospitals, preoperative anaemia management was organized by anaesthetists. Diagnostics and treatment focused on iron deficiency anaemia which, in most hospitals, was corrected with intravenous iron. CONCLUSION: Implementation and approaches of preoperative anaemia management vary across Europe with a primary focus on treating iron deficiency anaemia. Findings of this survey motivated the hospitals involved to critically evaluate their practice and may also help other hospitals interested in PBM to develop action plans for diagnosis and management of preoperative anaemia.

Patient Blood Management: Recommendations From the 2018 Frankfurt Consensus Conference.

IMPORTANCE: Blood transfusion is one of the most frequently used therapies worldwide and is associated with benefits, risks, and costs. OBJECTIVE: To develop a set of evidence-based recommendations for patient blood management (PBM) and for research. EVIDENCE REVIEW: The scientific committee developed 17 Population/Intervention/Comparison/Outcome (PICO) questions for red blood cell (RBC) transfusion in adult patients in 3 areas: preoperative anemia (3 questions), RBC transfusion thresholds (11 questions), and implementation of PBM programs (3 questions). These questions guided the literature search in 4 biomedical databases (MEDLINE, EMBASE, Cochrane Library, Transfusion Evidence Library), searched from inception to January 2018. Meta-analyses were conducted with the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) methodology and the Evidence-to-Decision framework by 3 panels including clinical and scientific experts, nurses, patient representatives, and methodologists, to develop clinical recommendations during a consensus conference in Frankfurt/Main, Germany, in April 2018. FINDINGS: From 17 607 literature citations associated with the 17 PICO questions, 145 studies, including 63 randomized clinical trials with 23 143 patients and 82 observational studies with more than 4 million patients, were analyzed. For preoperative anemia, 4 clinical and 3 research recommendations were developed, including the strong recommendation to detect and manage anemia sufficiently early before major elective surgery. For RBC transfusion thresholds, 4 clinical and 6 research recommendations were developed, including 2 strong clinical recommendations for critically ill but clinically stable intensive care patients with or without septic shock (recommended threshold for RBC transfusion, hemoglobin concentration <7 g/dL) as well as for patients undergoing cardiac surgery (recommended threshold for RBC transfusion, hemoglobin concentration <7.5 g/dL). For implementation of PBM programs, 2 clinical and 3 research recommendations were developed, including recommendations to implement comprehensive PBM programs and to use electronic decision support systems (both conditional recommendations) to improve appropriate RBC utilization. CONCLUSIONS AND RELEVANCE: The 2018 PBM International Consensus Conference defined the current status of the PBM evidence base for practice and research purposes and established 10 clinical recommendations and 12 research recommendations for preoperative anemia, RBC transfusion thresholds for adults, and implementation of PBM programs. The relative paucity of strong evidence to answer many of the PICO questions supports the need for additional research and an international consensus for accepted definitions and hemoglobin thresholds, as well as clinically meaningful end points for multicenter trials.

[Transfusion practice: what's new?] / Ce qui est nouveau dans la pratique de la transfusion.

Transfusion practice: what's new? Among many novelties in the field of transfusion, three are particularly noteworthy, as they significantly impact clinical practice of blood components transfusion and patients' safety. Patient blood management, evidence based and multidisciplinary, aims to optimize the management of each patient who may require transfusion. A medical and rational application of restrictive transfusion policies combined with alternatives to transfusion will lead to both better patient management and a reduction in exposure to blood components and related risks. Multidisciplinary training on prescribing and transfusion counseling, a suitable haemovigilance and a developed clinical research will support the development of patient blood management. The application of mitigation methods for infectious agents is now widespread for platelets and therapeutic plasma. And the concomitant transfusion of plasma, platelets and red blood cells has become a therapeutic standard for patients with severe haemorrhagic shock.

Ce qui est nouveau dans la pratique de la transfusion. Parmi de nombreuses nouveautés dans le domaine de la transfusion, trois sont particulièrement marquantes, par leur incidence sur la pratique clinique de la transfusion de produits sanguins labiles et la sécurité des patients. La gestion du sang du patient, fondée sur des preuves scientifiques, et multidisciplinaire, vise à optimiser la prise en charge de chaque patient qui pourrait avoir besoin de transfusion. Une application médicale et rationnelle de politiques de transfusion restrictives combinées à des alternatives à la transfusion amènera à la fois une meilleure prise en charge des patients et une réduction de l'exposition aux produits sanguins et des risques qui y sont liés. Une formation multidisciplinaire concernant la prescription et le conseil transfusionnel, une hémovigilance adaptée et une recherche clinique développée soutiendront le développement de la gestion du sang du patient. L'application de méthodes d'atténuation des agents infectieux transmissibles est aujourd'hui généralisée pour les plaquettes et le plasma thérapeutique. Et la transfusion concomitante de plasma, de plaquettes et de globules rouges est devenue un standard thérapeutique pour les patients en état de choc hémorragique sévère.

Perioperative Patient Blood Management (excluding obstetrics): Guidelines from the French National Authority for Health.

The French National Authority for Health (HAS) recently issued guidelines for patient blood management (PBM) in surgical procedures. These recommendations are based on three usual pillars of PBM: optimizing red cell mass, minimizing blood loss and optimizing anemia tolerance. In the preoperative period, these guidelines recommend detecting anemia and iron deficiency and taking corrective measures well in advance of surgery, when possible, in case of surgery with moderate to high bleeding risk or known preoperative anemia. In the intraoperative period, the use of tranexamic acid and some surgical techniques are recommended to limit bleeding in case of high bleeding risk or in case of hemorrhage, and the use of cell salvage is recommended in some surgeries with a major risk of transfusion. In the postoperative period, the limitation of blood samples is recommended but the monitoring of postoperative anemia must be carried out and may lead to corrective measures (intravenous iron in particular) or more precise diagnostic assessment of this anemia. A "restrictive" transfusion threshold considering comorbidities and, most importantly, the tolerance of the patient is recommended postoperatively. The implementation of a strategy and a program for patient blood management is recommended throughout the perioperative period in healthcare establishments in order to reduce blood transfusion and length of stay. This article presents an English translation of the HAS recommendations and a summary of the rationale underlying these recommendations.

Phenotypic and functional analyses of KIR3DL1+ and KIR3DS1+ NK cell subsets demonstrate differential regulation by Bw4 molecules and induced KIR3DS1 expression on stimulated NK cells.

Recently, the Z27 mAb was shown to recognize the NK cell-activating receptor KIR3DS1, and several genetic studies suggest that the most probable ligands of KIR3DS1 are HLA class I molecules with the Bw4 motif. Despite these findings, the attempts to establish a functional interaction between KIR3DS1 and its potential ligand have been unsuccessful. Here, we study the proliferation and cytotoxicity of KIR3DS1(+) NK cells, compared with KIR3DL1(+) NK cells, according to the Bw4(+) or Bw4(-) allogeneic environment. Our results show for the first time that KIR3DS1 expression on NK cells can be induced after exposure to stimulator cells (221, K562, EBV-B cell lines, and B cells), polyinosinic-polycytidylic acid, IL-15, or IL-2. Furthermore, whereas KIR3DL1(+) NK cell proliferation and cytotoxicity were inhibited in a Bw4(+) but not a Bw4(-) context, KIR3DS1(+) NK cell functions were not influenced by the presence of Bw4 on target cells. Nevertheless, despite the absence of demonstrated regulation of KIR3DS1(+) NK cell functions by HLA-Bw4 molecules, we found a higher KIR3DS1(+) NK cell frequency and higher levels of KIR3DS1 expression in Bw4(+) compared with Bw4(-) individuals. Altogether, these results suggest that KIR3DS1 does not recognize HLA-Bw4 molecules in a physiological context, and they highlight the induced expression of KIR3DS1 observed on stimulated NK cells and the higher frequency of KIR3DS1(+) NK cells in Bw4(+) individuals. Because a protective KIR3DS1-Bw4 association has been reported in viral infections, our results further the understanding of the role of KIR3DS1(+) NK cells in controlling viral infections.

Discrimination between the main activating and inhibitory killer cell immunoglobulin-like receptor positive natural killer cell subsets using newly characterized monoclonal antibodies.

Natural killer (NK) cells are key components of the innate anti-viral and anti-tumour immune responses. NK cell function is regulated by the interaction of killer cell immunoglobulin-like receptors (KIR) with human leucocyte antigen (HLA) class I molecules. In this study, we report on the generation of KIR-specific antibodies allowing for discrimination between activating and inhibitory KIR. For this purpose, BALB/c mice were immunized with human KIR2DS2 recombinant protein. The precise specificity of KIR2DS2-specific clones was determined on KIR-transfected BW cells and KIR-genotyped NK cells. When used in combination with EB6 (KIR2DL1/2DS1) or GL183 (KIR2DL2/2DL3/2DS2), two KIR-specific monoclonal antibodies (mAbs), 8C11 (specific for KIR2DL1/2DL2/2DL3/2DS2) and 1F12 (specific for KIR2DL3/2DS2), discriminated activating KIR2DS1 (8C11(-) EB6(+)) from inhibitory KIR2DL1 (8C11(+) GL183(-)) and KIR2DL2 (1F12(-) GL183(+)), while excluding the main HLA-Cw-specific KIR. Using these mAbs, KIR2DS1 was shown to be expressed on the surface of NK cells from all individuals genotyped as KIR2DS1(+) (n = 23). Moreover, KIR2DS1 and KIR2DL1 were independently expressed on NK cells. We also determined the amino acid position recognized by the 8C11 and 1F12 mAbs, which revealed that some KIR2DL1 allele-encoded proteins are not recognized by 8C11. Because most available anti-KIR mAbs recognize both inhibitory and activating forms of KIR, these newly characterized antibodies should help assess the expression of activating and inhibitory KIR and their functional relevance to NK biology.

Autologous and allogeneic HLA KIR ligand environments and activating KIR control KIR NK-cell functions.

NK-cell function is regulated by a balance between inhibitory and activating killer cell immunoglobulin-like receptors (KIR) that specifically recognize HLA class I molecules. Using KIR-specific mAb to discriminate between KIR2DS1 and KIR2DL1 receptors, we show that KIR2DS1(+) NK cells are C2-alloreactive only from C2(-) individuals. Moreover, using an in vitro model of NK-cell expansion, we show here that the frequency of KIR2DL1(+) NK cells is significantly higher in the absence of C2 ligand on stimulator EBV-B cells than in its presence. This observation was made regardless of the presence or absence of the autologous C2 ligand, suggesting that the C2(-) EBV-B stimulator cells used in this in vitro model could activate unlicensed KIR2DL1(+) NK cells. In the case of KIR2DL1(+)/S1(+) genotyped individuals, KIR2DS1(+) NK-cell frequency was increased after stimulation with C2(+) compared with C2(-) stimulator B cells, but only from C2(-) individuals. Altogether, these data highlight the C2 alloreactivity of KIR2DS1(+) NK cells that is only observed in C2(-) individuals. These results provide new insights into the way in which NK KIR cell expansion might be regulated in an allogeneic environment.

[Evaluation of the professional practices of physicians in transfusion technology and medicine]. / L'évaluation des pratiques professionnelles des médecins en technologie et médecine transfusionnelles.

The evaluation of the professional practices (EPP) is obligatory for all the physicians since July 1, 2005 for a first five-year period. It represents one of the components of the continuous medical training (CMT). The French Society of Blood Transfusion and National Institute of Blood Transfusion are the promoters of the EPP in transfusion technology and medicine. Initially, the programs of EPP will be conceived and controlled by experts and will relate to their basic activities. During a five years cycle, the physician taking part in a program must validate a specific action and take part in a rolling programme. At the end of the programme, the physician will receive a certificate issued by National Institute of Blood Transfusion and will have to submit it to a committee placed under the responsibility of the regional physicians' committee.

Selection strategies for newly registered blood donors in European countries.

BACKGROUND: Two selection strategies for newly-registered blood donors are available: a single-visit selection called the standard selection procedure (SSP), and a two-stage selection named predonation and donation screening (PDS). This study reviews the selection strategies for newly-registered donors currently applied in European countries. MATERIAL AND METHODS: We collected data on donor selection procedures, blood donation, laboratory screening and HIV, HCV and HBV positive donors/donations from 2010 to 2013 in 30 European countries by using questionnaires. We grouped the countries according to the applied selection strategy, and for each country, we calculated the 4-year prevalence of confirmed positive results indicating the presence of overall and recent HIV, HCV and HBV infections among first-time and repeat donations and among newly-registered donors. RESULTS: Most of the 24 countries (80%) apply the SSP strategy for selection of newly-registered donors. Twenty-two countries (73.3%) employ a nucleic acid amplification testing in addition to the mandatory serological screening. The survey confirms a higher overall prevalence of HIV, HCV and HBV infections among first-time donations and newly-registered donors than among repeat donations. In contrast, the prevalence of recently acquired HIV and HCV infections was lower among first-time donations and newly-registered donors than among repeat donations, but higher for recent HBV infections (6.7/105 vs 2.6/105 in the SSP setting and 4.3/105 vs 0.5/105 in one country using PDS). The relatively low numbers of infected donors selected by PDS impeded accurate assessment of the prevalence of recent infections in first-time donations. DISCUSSION: The data from European countries provide inconclusive evidence that applying PDS reduces the risk of donations being made in the diagnostic window of first-time donors. The impact of PDS on the risk of window-period donations and blood donor management needs further investigation.

Development of murine monoclonal antibodies to methamphetamine and methamphetamine analogues.

Methamphetamine and ecstasy are addictive drugs that cause major health problems in young people. Here we report on the development of high-affinity monoclonal antibodies to methamphetamine and its analogues, which may constitute powerful tools for antibody-based therapy. Six haptens, methamphetamine and ecstasy analogues, were synthesized, linked to a carrier protein and injected into mice. Several specific monoclonal antibodies were subsequently obtained following fusion of splenocytes from the immunized animals, with Sp2/O cells. Antibody specificity was fully investigated by competition ELISA, using a series of analogues, to identify specific amphetamine and/or ecstasy-specific antibodies. Antibody affinity was estimated to be in the range of 10(8) M(-1) with an enantiomeric hapten. Finally, two characteristic hybridoma clones (DAS-M243-6H5 and DAS-M278-4B12), secreting specific and potent mAbs were isolated. The development of drug-specific antibodies as in this study may provide promising therapeutic insight into how to neutralize methamphetamine in vivo during acute intoxication.

Rethinking blood components and patients: Patient blood management. Possible ways for development in France.

As any therapeutic means, blood transfusion requires regular evaluation, particularly for its indications, effectiveness and risks. A better awareness of the risks of blood transfusion, the availability of randomized clinical trials, the evolution of the quality of blood components, and the economic constraints shared by all countries, all have led to rethink both transfusion therapy as a whole and the organization of the transfusion chain from donor to recipient. In this context, patient blood management (PBM) appears as an evidence-based, patient centred, multidisciplinary approach, aiming to optimise the care of patients who might need transfusion and consequently the use of blood products. This paper presents updated scientific bases of PBM and the three pillars founding it. As PBM is developing fast in other European countries, this review proposes ways to explore for its development in France. It finally proposes to integrate PBM in a wider and coordinated approach of the blood supply management, with tools to improve the effectiveness and efficiency of the transfusion chain, starting with the needs of the patients and ending with an optimum treatment of the patient, including the appropriate number of blood components of the required quality. A better understanding, implementation and assessment of this coordinated global approach, allowing to adapt donor collections to the patients' needs in compliance with safety requirements for patients and donors, in a coordinated way, will certainly be a major challenge for transfusion medicine in the near future, for the benefit of patients, donors and all other stakeholders involved in the transfusion chain.

Blood donor selection in European Union directives: room for improvement.

BACKGROUND: Transfusion-transmissible infections have made both blood bankers and health authorities overly cautious. The general public expects and hence reinforces this policy. To obtain a high level of blood product safety, blood and plasma donors have to meet increasingly stringent eligibility criteria; however, it is not known whether this policy translates into improved outcomes for patients. There is a risk that the management of donors does not match the ambition of greater safety for patients. European directives related to the collection process and donor selection will probably be reconsidered in the next few years. MATERIAL AND METHODS: The development of European directives on donor selection and their basis in the literature were reviewed with an emphasis on the background and considerations for eligibility criteria to be included in the directives. RESULTS: The precautionary principle appears to be the predominant reason behind the set of eligibility criteria. However, the formal eligibility criteria, put into force in 2004, do not balance with the developments of the past decade in laboratory tests and measures that have substantially reduced actual infection risks. In no cases were the effects of eligibility criteria on the donor pool and donor well-being quantified. Regional differences in the epidemiology of transfusion-transmissible infections were not taken into consideration either. DISCUSSION: First, the Authors promote the collection of epidemiological data on the incidence and prevalence of conditions in the general population and in blood and plasma donors which could pose a risk for transfused patients, in order to use these data as a basis for decision-making in donor-selection policies. Second, the Authors suggest including allowance for differential deferral criteria throughout Europe, based on factual risk levels. There should be an accepted balance between donor and patient welfare, and also between risk to transfusion safety and risk of compromising the blood supply.

NK-KIR transcript kinetics correlate with acute graft-versus-host disease occurrence after allogeneic bone marrow transplantation.

Natural killer (NK) cell alloreactivity observed during stem cell transplantation (SCT) can be either beneficial (graft-versus-leukemia effect) or detrimental to the host (graft-versus-host disease). Killer immunoglobulin-like receptors (KIRs), expressed on NK and CD8 memory T cells, are regulated at a posttranscriptional level and, because there are currently no KIR-specific antibodies available, the analysis of these receptors remains elusive. To better define the role of cells expressing KIR after SCT, we studied KIR transcript repertoires in 29 grafted patients who received myeloablative or nonmyeloablative regimens. We restricted our analysis to 3DL1, 3DL2, 2DL4, 2DS3, and 2DS4 KIR transcripts 6 months after SCT. Absolute counts of NK and CD8 T cells were determined by flow cytometry, and KIR transcripts were quantified by real-time reverse transcription polymerase chain reaction at days 14, 28, 60, 100, and 180 after transplantation. Three groups of patients were identified. Groups I and III were characterized by the absence or a delayed appearance of KIR transcripts, which correlated with the highest risk of acute graft-versus-host disease (aGvHD). In contrast, in group II, a significant transcript peak was observed early, and only one patient suffered from aGvHD (p = 0.025). Thus determining the kinetics of KIR transcription should make it possible to identify transplanted patients at a high risk of developing aGvHD.

[Blood transfusion: the challenges for tomorrow?]. / Transfusion sanguine : quels enjeux pour demain ?

As any therapeutic means, blood transfusion requires regular evaluation, particularly for its indications, effectiveness and risks. The availability of randomized clinical trials, the evolution of the quality of blood components, and the economic constraints shared by all countries, all lead to rethink both transfusion therapy as a whole and the organization of the transfusion chain from donor to recipient. The main tools available to improve transfusion and the transfusion chain management are the following: programs of patient blood management (PBM) to optimize the use of blood products with a patient centred approach, blood supply management tools to improve the effectiveness and efficiency of the transfusion chain, donor management tools to adapt donor collections to the patients' needs in compliance with safety requirements for patients and donors, and coordination of these activities. A better understanding of these tools and their implementation will certainly be major challenges for transfusion medicine in the near future. Integrating these evolutions in regulations through the revision of the European Directives on blood and blood components (the review process is expected to be launched in 2015) should enroll them in the long term, for the benefit of patients, donors and all other stakeholders involved in the transfusion chain.

Identification of the antibodies involved in B-cell crossmatch positivity in renal transplantation.

BACKGROUND: The significance of a positive B-cell crossmatch (BCM) in kidney transplantation has always been controversial in the evaluation of its implications on graft survival and specificity of the antibodies involved. METHODS: We have investigated the sera of 62 recipients of a kidney allograft transplanted across a positive BCM (T negative) for the presence of autoantibodies and anti-human leukocyte antigen (HLA) class I and II antibodies, using a combination of lymphocytotoxicity, enzyme-linked immunosorbent assay (ELISA), and flow cytometry tests. The controls were the 930 patients transplanted over the same period of time with a negative T and BCM. RESULTS: Autoantibodies were detected in 16%, and donor specific anti-HLA class II antibodies, mainly DQ, in 23% of the patients. None had antibodies against donor HLA class I. The target of the antibodies was not identified in 61%. Graft survival was comparable in the controls and in the +BCM patients, with nondonor-specific HLA reactivity. Patients with donor-specific anti-HLA class II antibodies had lower early graft survival and a higher incidence of vascular rejection. However, long-term allograft survival was similar to that of the other groups. CONCLUSION: These data suggest that in 77% of the patients, BCM positivity was not related with anti-HLA antibodies, and, in this case, graft survival was similar to that of the -BCM controls. In a minority of patients, anti-HLA class II antibodies were responsible for the +BCM, and their presence was associated with lower early, but not long-term, graft survival. Consequently, a +BCM should not systematically contraindicate kidney transplantation.

Relevance of KIR gene polymorphisms in bone marrow transplantation outcome.

Natural Killer (NK) cells may be involved both in allogeneic bone marrow transplantation (BMT) rejection and graft-versus-host disease (GVHD). The physiologic functions of NK cells appear to be regulated by diverse non-inhibitory and inhibitory receptors including the killer cell immunoglobulin-like receptors (KIR). Although human leukocyte antigen (HLA) epitope mismatches are well-known causes of NK alloreactivity, the role of KIR genes in transplantation remains to be further investigated. In this study, we have evaluated whether KIR genotype differences between donors and recipients of HLA identical (related and unrelated) compared with HLA non-identical unrelated BMT, had an impact on transplantation outcome. Our results show that 5 of 15 KIR genes were always identical in donors and recipients and most variations were observed in the number and specificity of noninhibitory KIR genes. Based on the presence or absence of particular KIR genes, 70 different genotypes were obtained from all individuals. According to the donor or recipient KIR genotype, different combination patterns were described. Interestingly, when the recipient KIR genotype was "included" in the donor KIR genotype, 100% (11/11 pairs) of unrelated BMT developed GVHD compared with 60% (18/30) in all other combinations (p = 0.012). In contrast, no GVHD was observed in related BMT when the recipient KIR genotype was "included" in the donor KIR genotype (p = 0.0001). In conclusion, our results reveal a great diversity for KIR genotypes in donors and recipients of BMT and that the risk of GVHD was maximum in unrelated BMT when the recipient KIR genotype was "included" in the donor KIR genotype.

Investigation of the impact of HLA-DPB1 matching status in 10/10 HLA matched unrelated hematopoietic stem cell transplantation: results of a French single center study.

The impact of HLA-DPB1 mismatches after unrelated hematopoietic stem cell transplantation (HSCT) remains controversial. We retrospectively analyzed the impact of permissive/non-permissive HLA-DPB1 mismatches on the outcome of 141 patients who underwent 10/10 HLA allelic-matched unrelated HSCT. Each pair was classified according to the 3 (TCE3) and 4-group (TCE4) algorithm based on DPB1 alleles immunogenicity. Outcome analysis revealed that TCE3 and TCE4 non-permissive HLA-DPB1 disparities were not associated with worsened overall survival, relapse risk neither risk of acute GvHD. Overall, this single center retrospective study does not confirm the adverse prognostic of non-permissive HLA-DPB1 mismatches.