Mika Matsuhashi

The frequencies of human neutrophil alloantigens among the Japanese population

Human neutrophil antigens (HNAs) play an important role in a variety of clinical conditions including immune-mediated neutropenia, non-hemolytic transfusion reactions, and transfusion-related acute lung injury. The aim of this study was to investigate the frequency distribution of HNAs-1 to -5 among the Japanese population. We analyzed samples from 570 healthy Japanese by molecular and serologic techniques to estimate the gene frequencies of HNAs-1 to -5. DNA samples were obtained and typed for the HNA-1 (n = 523), -3 (n = 570), -4 (n = 570), and -5 (n = 508), by molecular techniques. The HNA-1 genotype was determined by using a commercial polymerase chain reaction-reverse sequence-specific oligonucleotide probes (PCR-rSSOP) kit. The HNA-3 to -5 genotypes were determined by the PCR-sequence specific primer (PCR-SSP), previously described, with a small modification. The HNA-2a phenotype was determined in 301 donors by granulocyte immunofluorescence test. In Japanese, the gene frequencies of HNA-1a, -1b, and -1c were 0.623, 0.377, and 0.000, respectively. The frequency of HNA-2a phenotype was 0.987, and the gene frequencies of HNA-3a and -3b were 0.654 and 0.346, respectively. HNA-4a and -4b were found at 1.000 and 0.000, respectively, and HNA-5a and -5b at 0.840 and 0.160, respectively. We describe, for the first time, the frequencies of all HNAs (HNA-1 to -5) among the Japanese population. This study will be helpful for the prediction of the risk of alloimmunization to HNA, especially to determine the risk of HNA alloantibody production by transfusion of HNA incompatible blood and feto-maternal incompatibility.

Effects of universal vs bedside leukoreductions on the alloimmunization to platelets and the platelet transfusion refractoriness

BACKGROUND Multiple platelet exposure induces anti-HLA and/or anti-HPA antibody production, which may cause platelet transfusion refractoriness (PTR). In Japan, the universal pre-storage leukocyte reduction (ULR) was fully implemented since 2006, but prior to ULR, in our institution, leukocyte reduction filters were routinely used at the bedside (bedside leukoreduction, BSLR) for all onco-hematological patients receiving multiple platelet transfusions. OBJECTIVE We retrospectively compared patients receiving platelet transfusions in the era of ULR with those of BSLR era. MATERIALS AND METHODS Patients of the BSLR group (409 cases) and the ULR group (586 cases) were compared in terms of alloimmunization and immunological PTR. The clinico-pathological features, including gender, history of pregnancy, number of exposed transfusion donors, periods of transfusion, and prior stem cell transplantation were compared, and the risk factors of alloimmunization were determined. RESULTS The antibody detection rate was significantly higher in the ULR compared to BSLR group (8.7% vs. 5.4%), as well as the immunological PTR rate (7.3% vs. 3.2%). By the multivariate analysis, female gender and the number of platelet donor exposure, but not universal leukoreduction or transfusion period, were found to be the risk factors strongly associated with alloantibody formation. CONCLUSION Although ULR may be superior to BSLR in terms of preventing non-hemolytic transfusion reactions, BSLR was found to be as effective as ULR in terms of preventing platelet alloimmunization and refractoriness. Thus, BSLR should be actively indicated as a realistic alternative in developing countries, before the universal leukoreduction is fully implemented.

The current status of autologous blood transfusion in Japan--the importance of pre-deposit autologous blood donation program and the needs to achieve patient blood management.

BACKGROUND Autologous blood transfusion (ABT) is currently considered the safest transfusion, since the risks of allogeneic immunological reaction and viral transmission are theoretically null. Although its use has declined in Western countries in the recent decade, it has been progressively expanded in Japan. With the widening of the concept of patient blood management (PBM), which aims to prevent the harmful adverse effects of the exposure to allogeneic blood, the importance of the ABT has once again gained interest. STUDY DESIGN AND METHODS Here, we retrospectively analyzed the cases pre-depositing autologous blood for an elective surgery in the period of January 2000 to December 2010 in our hospital, where a pre-deposit autologous blood donation (PAD) program has been established in 2006, in an attempt to analyze the improvements achieved, and the problems remaining to achieve patient blood management. RESULTS The PAD program contributed for the further improvement of ABT, and the number of participating patients increased, especially in the period 2002-2003, when the idea of PAD program implementation came out. By simple extrapolation of the ABT data to allogeneic blood, ABT was found to be superior in terms of cost-effectiveness. However, problems such as the high wastage rate, and the inappropriate transfusion triggers remain to be solved. CONCLUSION ABT plays the central role in PBM, but to achieve the real PBM, there is need to indicate ABT appropriately, according to the individual needs, and use it adequately, without discarding. Our present data reflect the present status of the ABT performance in Japan, and will serve as the basis for the development of strategies to achieve safe and appropriate performance of ABT, and consequently, achieve PBM.

The first case of alloantibody against human platelet antigen-15b in Japan: possible alloimmunization by a hydatidiform mole

BACKGROUND: The involvement of the human platelet antigen (HPA)‐15 system in neonatal alloimmune thrombocytopenia (NAIT) has been reported in various populations, but not in the Japanese population. In Japan, the mixed passive hemagglutination assay (MPHA) is used for detection of HPA alloantibodies. However, most of the reported cases of HPA‐15 incompatibility are based on the monoclonal antibody immobilization of platelet antigen (MAIPA) assay or immunoprecipitation; thus there is a possibility that HPA‐15 alloantibodies are not efficiently detected by the MPHA, and currently, the causative antibody is not detectable in approximately half of the suspected NAIT cases in Japan.

The role of alloantibodies against human platelet antigen-15 in multiply platelet transfused patients

Several studies have documented the role of antibodies against human platelet (PLT) antigen (HPA)‐15 in alloimmune‐mediated thrombocytopenia including neonatal alloimmune thrombocytopenia, PLT transfusion refractoriness (PTR), and posttransfusion purpura in Caucasian persons. However, the relevance of anti‐HPA‐15 in PTR among the Japanese population is still unclear.

The effect of pre-storage whole-blood leukocyte reduction on cytokines/chemokines levels in autologous CPDA-1 whole blood

BACKGROUND In this study, we aimed to investigate the effectiveness of pre-storage leukocyte filtration of autologous blood (AB), especially focusing on the cytokines/chemokines accumulation on blood products. MATERIALS AND METHODS After approval of the ethics committee of the University of Tokyo, a total of 26 orthopedic patients, who donated AB prior to surgery after informed consent, were enrolled. The effects of filtration on blood cell counts were analyzed, and the accumulation of cytokines and chemokines were measured on pre- and post-leukoreduced (LR) samples, using the Luminex system. The time-dependent changes of the cytokines/chemokines and the effect of the filtration on their concentration were analyzed, and compared with the normal plasma levels reported in the literature. RESULTS LR effectively reduced the number of leukocytes and platelets, without affecting that of red cells. The concentration of most of the cytokines/chemokines analyzed, except the EGF, sCD40-L and sFas-L, decreased time-dependently of storage or did not change in pre-LR samples. However, EGF, sCD40L and sFas-L were significantly reduced by LR. Some, such as IL-8 and RANTES, were also importantly decreased by LR, and others, such as IL-1β and TNF-α, were not significantly affected by LR. CONCLUSIONS Leukocyte filtration effectively removes platelets and leukocytes from AB, thus preventing the accumulation of cytokines/chemokines. Since adverse effects due to AB transfusion, although rare, are observed, there is need to consider the implementation of pre-storage leukocyte reduction (PSLR) for AB.

The importance of platelet antigens and antibodies in immune-mediated thrombocytopenia

Platelet antigens/antibodies play an important role in immune mediated‐thrombocytopenia. Here, we review the clinical conditions associated with anti‐platelet alloantibodies, giving special emphasis to the differences in human platelet antigen (HPA) frequency distribution between Caucasian and Asian populations. Also, we describe the presently available methods for the detection of anti‐platelet alloantibodies, and the activities of the International Society of Blood Transfusion (ISBT) Platelet Immunology Working Parties, which play an active role in the exchange of information and materials among the labs involved in platelet immunobiology research worldwide, and have significantly contributed for the development of this field.

Advances in granulocyte test methodologies

Alloantibodies to human neutrophil antigens (HNA) are involved in clinical conditions such as neonatal alloimmune neutropenia (NAN), autoimmune neutropenia (AIN) and transfusion‐related acute lung injury (TRALI). For the diagnosis of these conditions, the detection of the causative antibody is essential. Presently, the use of a combination of granulocyte agglutination assay (GAT) and granulocyte immunofluorescence test (GIFT) for the screening of granulocyte antibodies, followed by the determination of antibody specificity by the monoclonal antibody‐specific immobilization of granulocyte antigens (MAIGA) is recommended by the ISBT Working Party on Granulocyte Immunobiology. In Japan, the mixed‐passive hemagglutination (MPHA) assay, a method originally developed for the detection of anti‐platelet antibodies, was adapted for the testing of anti‐granulocyte antibodies. Although various technologies are available, presently, no one of the methods alone is able to detect all clinically relevant antibodies, thus their combination is important, and the development of new methodologies is desired. In this review, we describe the presently available classical methods for anti‐granulocyte antibody detection, including GIFT, GAT, MAIGA and MPHA, and also the new technologies, especially focusing on the advantages and problems of the different methods.

Inhibition of lysophosphatidic acid increase by prestorage whole blood leukoreduction in autologous CPDA-1 whole blood

Lysophosphatidylcholine (LPC) has been implicated in the onset of transfusion‐related acute lung injury (TRALI). In plasma, LPC is converted to lysophosphatidic acid (LPA) by autotaxin (ATX). The effect of leukoreduction in the accumulation of these bioactive lipids and ATX in human autologous blood has not been fully investigated.

Granulocyte antibody detection – the role of MPHA

Human neutrophil antigens (HNA) are involved in the pathogenesis of a variety of clinical conditions, such as neonatal immune neutropenia (NIN), refractoriness to granulocyte transfusions, alloimune neutropenia after bone marrow transplantation, febrile transfusion reactions, and transfusion‐related acute lung injury (TRALI). The accurate detection of granulocyte antibodies is essential for the diagnosis and prevention of the clinical conditions in which these antibodies are involved, especially TRALI. The international granulocyte immunology workshop recommends the use of granulocyte agglutination test (GAT) and granulocyte immunofluorescence test (GIFT) for the screening of granulocyte antibody, and the use of monoclonal antibody‐specific immobilization of granulocyte antigen (MAIGA) assay for the determination of the antibody specificity. Presently, however, no single technique available is enough to detect all clinically relevant granulocyte antibodies. Here, we describe the advantages and disadvantages of the mixed‐passive hemagglutination (MPHA) assay in the general context of granulocyte serology.