Loss-Prone HLA Class I Alleles Inform Outcomes of Early Hematopoietic Cell Transplantation in Acquired Aplastic Anemia.

HLA class I allele loss in acquired aplastic anemia (AA) represents an immune escape from the T cell-mediated pathogenesis. We investigated the impact of loss-prone HLA alleles on the hematopoietic cell transplantation (HCT) outcomes using registry data of 875 Japanese patients with acquired AA. HLA associations were evident exclusively among 399 patients who received HCT within 1 year of the diagnosis, consistent with the predominance of HLA loss in this group.

Toggling of NKG2A expression drives functional specialization of iPSC-derived CAR NK cells.

Induced pluripotent stem cell (iPSC)-derived natural killer (iNK) cells offer a promising platform for off-the-shelf immunotherapy against hematological malignancies. NK cell function is dynamically regulated through education driven by inhibitory receptors, including CD94/NKG2A and killer cell immunoglobulin-like receptors (KIR). However, the acquisition of inhibitory receptors in iNK cells and their role during differentiation and education remains poorly defined.

[Validation of gradient-boosted models for non-invasive diagnosis of myelodysplastic neoplasms: a single-center analysis].

Bone marrow examination is essential for the definitive diagnosis of myelodysplastic neoplasms (MDS). However, non-invasive diagnostic approaches are needed for patients who cannot tolerate the procedure, especially elderly patients. This study aimed to validate the diagnostic accuracy of non-invasive gradient-boosted models (GBMs) in Japanese patients with MDS.

Esophageal involvement of mantle cell lymphoma presenting with multiple lymphomatous polyposis: A single-center study.

Background: In addition to nodal lesions, over 30% of mantle cell lymphomas (MCLs) also have gastrointestinal involvement, characteristically presenting as multiple lymphomatous polyposis (MLP), which rarely involve the esophagus. Most related papers have been case reports, and no comprehensive studies have been conducted; thus, the actual clinical situation has remained unknown for a long time.

Aim: To elucidate the actual clinical situation of esophageal involvement of MCL presenting with MLP, including its prognosis.

Therapeutic switch from plasma to recombinant ADAMTS13 for patients with congenital TTP from Japanese real-world data.

Congenital thrombotic thrombocytopenic purpura (cTTP) is an ultrarare disorder characterized by thrombocytopenia, microangiopathic hemolytic anemia, and ischemic organ damage caused by pathogenic ADAMTS13 (a disintegrin and metalloproteinase with thrombospondin type 1 motif, member 13) variants. ADAMTS13-containing product, including fresh-frozen plasma (FFP), and plasma-derived factor VIII concentrates are commonly used to supply ADAMTS13; however, frequent hospital visits and allergic reactions are major drawbacks. A recombinant ADAMTS13 (rADAMTS13) was recently developed to address these issues.

Chronic graft-versus-host disease myelitis successfully treated with rituximab.

Chronic graft-versus-host disease (cGVHD) is a major serious complication after allogeneic stem-cell transplantation (allo-HSCT), and often mimics autoimmune diseases. Central nervous system (CNS) symptoms are rare manifestations of cGVHD, and are difficult to diagnose. CNS manifestations of cGVHD were discussed in the 2020 National Institutes of Health cGVHD Consensus Project as one of the "atypical cGVHD manifestations" with involvement of various organ systems other than classical cGVHD organs.

FLT3 inhibitors and hematopoietic cell transplantation prolong survival in patients with FLT3-ITD-positive AML.

Acute myeloid leukemia (AML) is an aggressive hematological malignancy with genetic alterations. The FMS-like tyrosine kinase 3 (FLT3) gene is frequently mutated in adult de novo AML, with two types of mutations: internal tandem duplication (ITD) and point mutations in the tyrosine kinase domain. This study aimed to investigate the impact of FLT3 inhibitors and hematopoietic cell transplantation (HCT) on survival outcomes in patients with FLT3-ITD AML in a real-world setting.

Transformed gastric mucosa-associated lymphoid tissue lymphoma originating in the colon and developing metachronously after eradication: A case report.

Background: () eradication treatment for primary gastric mucosa-associated lymphoid tissue (MALT) lymphoma has already been established. However, t (11;18) (q21;q21)/ translocation-positive lesions are a type of primary gastric MALT lymphoma in which a response to eradication treatment is difficult to achieve. In addition, trisomy 18 may be associated with diffuse large B-cell lymphoma (DLBCL) transformation of gastric MALT lymphoma.

Effect of peptide-binding motif on survival of HLA-haploidentical transplantation with post-transplant cyclophosphamide.

Peptide-binding motif (PBM) model, a hierarchical clustering of HLA class I based on their binding specificity, was developed to predict immunopeptidome divergence. The effect of PBM mismatches on outcomes is unknown in HLA-haploidentical haematopoietic cell transplantation with post-transplant cyclophosphamide (PTCy-haplo). We therefore conducted a retrospective study using national registry data in PTCy-haplo.

Significance of absolute neutrophil count before allogeneic hematopoietic stem cell transplantation in adult patients with aplastic anemia.

The impact of absolute neutrophil count (ANC) before allogenic hematopoietic stem cell transplantation (HSCT) on the outcomes for patients with aplastic anemia (AA) remains unclear. We retrospectively evaluated the relationship between ANC before transplantation and patient outcomes, involving 883 adult Japanese patients with AA who underwent allogeneic HSCT as their first transplantation between 2008 and 2020. Patients were divided into three groups based on ANC: 0/µL (n = 116); 1-199 (n = 210); and ≥ 200 (n = 557).

Initial Efficacy of the COVID-19 mRNA Vaccine Booster and Subsequent Breakthrough Omicron Variant Infection in Patients with B-Cell Non-Hodgkin's Lymphoma: A Single-Center Cohort Study.

It has been suggested that the effect of coronavirus disease 2019 (COVID-19) booster vaccination in patients with B-cell non-Hodgkin's lymphoma (B-NHL) is inferior to that in healthy individuals. However, differences according to histological subtype or treatment status are unclear. In addition, there has been less research on patients who subsequently develop breakthrough infections.

A temporal developmental map separates human NK cells from noncytotoxic ILCs through clonal and single-cell analysis.

Natural killer (NK) cells represent the cytotoxic member within the innate lymphoid cell (ILC) family that are important against viral infections and cancer. Although the NK cell emergence from hematopoietic stem and progenitor cells through multiple intermediate stages and the underlying regulatory gene network has been extensively studied in mice, this process is not well characterized in humans. Here, using a temporal in vitro model to reconstruct the developmental trajectory of NK lineage, we identified an ILC-restricted oligopotent stage 3a CD34-CD117+CD161+CD45RA+CD56- progenitor population, that exclusively gave rise to CD56-expressing ILCs in vitro.

Hereditary thrombocythemia due to splicing donor site mutation of THPO in a Japanese family.

Thrombopoietin (THPO) is an essential factor for platelet production. Hereditary thrombocythemia (HT) is caused by a germline mutation of THPO, MPL, or JAK2 and is inherited in an autosomal-dominant manner. We identified a Japanese family with HT due to a point mutation of the splicing donor site of the THPO gene (THPO c.

eradication treatment for primary gastric diffuse large B-cell lymphoma: A single-center analysis.

Background: Unlike the already established effect of () eradication on gastric mucosa-associated lymphoid tissue (MALT) lymphoma, its therapeutic effect on primary gastric diffuse large B-cell lymphoma (DLBCL) is still unclear.

Aim: To clarify the efficacy of eradication treatment for primary gastric DLBCL.

Methods: We reported on 3 new cases, and added them to 3 previously reported cases.

Mapping the chemotactic landscape in NK cells reveals subset-specific synergistic migratory responses to dual chemokine receptor ligation.

Background: Natural killer (NK) cells have a unique capability of spontaneous cytotoxicity against malignant cells and hold promise for off-the-shelf cell therapy against cancer. One of the key challenges in the field is to improve NK cell homing to solid tumors.

Methods: To gain a deeper understanding of the cellular mechanisms regulating trafficking of NK cells into the tumor, we used high-dimensional flow cytometry, mass cytometry, and single-cell RNA-sequencing combined with functional assays, creating a comprehensive map of human NK cell migration phenotypes.

Affibody-based hBCMA x CD16 dual engagers for NK cell-mediated killing of multiple myeloma cells.

We describe the development and characterization of the (to date) smallest Natural Killer (NK) cell re-directing human B Cell Maturation Antigen (hBCMA) x CD16 dual engagers for potential treatment of multiple myeloma, based on combinations of small 58 amino acid, non-immunoglobulin, affibody affinity proteins. Affibody molecules to human CD16a were selected from a combinatorial library by phage display resulting in the identification of three unique binders with affinities (K) for CD16a in the range of 100 nM-3 µM. The affibody exhibiting the highest affinity demonstrated insensitivity towards the CD16a allotype (158F/V) and did not interfere with IgG (Fc) binding to CD16a.

Booster effect of a third mRNA-based COVID-19 vaccine dose in patients with myeloid malignancies.

Background: We have reported that seroconversion rates after the second dose of mRNA-based COVID-19 vaccines for myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML) were 100% and 95% respectively, with no significant difference from healthy controls (HCs).However, there are very limited data for the response to a third vaccine dose in those patients.

Aims: In this complementary study, we investigated the booster effect of a third mRNA-based COVID-19 vaccine dose in patients with myeloid malignancies.

Allelic variation of KIR and HLA tunes the cytolytic payload and determines functional hierarchy of NK cell repertoires.

The functionality of natural killer (NK) cells is tuned during education and is associated with remodeling of the lysosomal compartment. We hypothesized that genetic variation in killer cell immunoglobulin-like receptor (KIR) and HLA, which is known to influence the functional strength of NK cells, fine-tunes the payload of effector molecules stored in secretory lysosomes. To address this possibility, we performed a high-resolution analysis of KIR and HLA class I genes in 365 blood donors and linked genotypes to granzyme B loading and functional phenotypes.

New onset of hypomegakaryocytic thrombocytopenia with the potential for progression to aplastic anemia after BNT162b2 mRNA COVID-19 vaccination.

Vaccination with a coronavirus disease-2019 (COVID-19) vaccine is an effective public health measure for reducing the risk of infection and severe complications from COVID-19. However, serious hematological complications after COVID-19 vaccination have been reported. Here, we report a case of new-onset hypomegakaryocytic thrombocytopenia (HMT) with the potential for progression to aplastic anemia (AA) that developed in a 46-year-old man 4 days after the fourth mRNA COVID-19 vaccination.

Humoral response to mRNA-based COVID-19 vaccine and booster effect of a third dose in patients with mature T cell and NK-cell neoplasms.

Patients with lymphoid malignancies have impaired humoral immunity caused by the disease itself and its treatment, placing them at risk for severe coronavirus disease-19 (COVID-19) and reduced response to vaccination. However, data for COVID-19 vaccine responses in patients with mature T cell and NK-cell neoplasms are very limited. In this study of 19 patients with mature T/NK-cell neoplasms, anti-severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) spike antibodies were measured at 3 months, 6 months, and 9 months after the second mRNA-based vaccination.

Fludarabine plus reduced-intensity busulfan versus fludarabine plus myeloablative busulfan in patients with non-Hodgkin lymphoma undergoing allogeneic hematopoietic cell transplantation.

Allogeneic hematopoietic cell transplantation (HCT) offers a possible cure for patients with relapsed and refractory non-Hodgkin lymphoma (NHL) through potentially beneficial graft versus lymphoma effects. However, allogeneic HCT is associated with high nonrelapse mortality (NRM). Fludarabine with reduced-intensity busulfan (Flu/Bu2) and myeloablative busulfan (Flu/Bu4) are commonly used in conditioning regimens for allogeneic HCT; however, data on their use in patients with NHL is limited.

Adaptive single-KIRNKG2C NK cells expanded from select superdonors show potent missing-self reactivity and efficiently control HLA-mismatched acute myeloid leukemia.

Background: Natural killer (NK) cells hold great promise as a source for allogeneic cell therapy against hematological malignancies, including acute myeloid leukemia (AML). Current treatments are hampered by variability in NK cell subset responses, a limitation which could be circumvented by specific expansion of highly potent single killer immunoglobulin-like receptor (KIR)NKG2C adaptive NK cells to maximize missing-self reactivity.

Methods: We developed a GMP-compliant protocol to expand adaptive NK cells from cryopreserved cells derived from select third-party superdonors, that is, donors harboring large adaptive NK cell subsets with desired KIR specificities at baseline.

Improved survival after single-unit cord blood transplantation using fludarabine and melphalan-based reduced-intensity conditioning for malignant lymphoma: impact of melphalan dose and graft-versus-host disease prophylaxis with mycophenolate mofetil.

We evaluated 413 adult patients with lymphoma who underwent unrelated cord blood transplantation (UCBT) with fludarabine and melphalan (FM)-based reduced-intensity conditioning between 2002 and 2017 to investigate longitudinal changes in outcomes and the optimal melphalan dose and graft-versus-host disease (GVHD) prophylaxis regimen. Outcomes were compared between FM80/100 (melphalan dose: 80 or 100 mg/m) and FM140 (melphalan dose: 140 mg/m), as well as between calcineurin inhibitor (CNI) plus methotrexate (MTX), CNI plus mycophenolate mofetil (MMF), and CNI alone. The 3-year overall survival (OS) and non-relapse mortality (NRM) rates improved over time (OS: 27% in 2000s vs.