The hepatic niche leads to aggressive natural killer cell leukemia proliferation through the transferrin-transferrin receptor 1 axis

Aggressive natural killer cell leukemia (ANKL) is a rare lymphoid neoplasm frequently associated with Epstein-Barr virus, with a disastrously poor prognosis. Owing to the lack of samples from patients with ANKL and relevant murine models, comprehensive investigation of its pathogenesis including the tumor microenvironment (TME) has been hindered. Here we established 3 xenograft mice derived from patients with ANKL (PDXs), which enabled extensive analysis of tumor cells and their TME. ANKL cells primarily engrafted and proliferated in the hepatic sinusoid. Hepatic ANKL cells were characterized by an enriched Myc-pathway and proliferated faster than those in other organs. Interactome analyses and in vivo CRISPR-Cas9 analyses revealed transferrin (Tf)-transferrin receptor 1 (TfR1) axis as a potential molecular interaction between the liver and ANKL. ANKL cells were rather vulnerable to iron deprivation. PPMX-T003, a humanized anti-TfR1 monoclonal antibody, showed remarkable therapeutic efficacy in a preclinical setting using ANKL-PDXs. These findings indicate that the liver, a noncanonical hematopoietic organ in adults, serves as a principal niche for ANKL and the inhibition of the Tf-TfR1 axis is a promising therapeutic strategy for ANKL.

Tγδ LGLL identifies a subset with more symptomatic disease: analysis of an international cohort of 137 patients

Tγδ large granular lymphocyte leukemia (LGLL) is a rare variant of T-cell LGLL (T-LGLL) that has been less investigated as compared with the more frequent Tαβ LGLL, particularly in terms of frequency of STAT3 and STAT5b mutations. In this study, we characterized the clinical and biological features of 137 patients affected by Tγδ LGLL; data were retrospectively collected from 1997 to 2020 at 8 referral centers. Neutropenia and anemia were the most relevant clinical features, being present in 54.2% and 49.6% of cases, respectively, including severe neutropenia and anemia in ∼20% of cases each. Among the various treatments, cyclosporine A was shown to provide the best response rates. DNA samples of 97 and 94 cases were available for STAT3 and STAT5b mutation analysis, with 38.1% and 4.2% of cases being mutated, respectively. Clinical and biological features of our series of Tγδ cases were also compared with a recently published Tαβ cohort including 129 cases. Though no differences in STAT3 and STAT5b mutational frequency were found, Tγδ cases more frequently presented with neutropenia (P = .0161), anemia (P < .0001), severe anemia (P = .0065), and thrombocytopenia (P = .0187). Moreover, Vδ2- cases displayed higher frequency of symptomatic disease. Overall, Tγδ cases displayed reduced survival with respect to Tαβ cases (P = .0017). Although there was no difference in STAT3 mutation frequency, our results showed that Tγδ LGLL represents a subset of T-LGLL characterized by more frequent symptoms and reduced survival as compared with Tαβ LGLL.

Immature Platelet Fraction and Its Kinetics in Neonates

Thrombocytopenia is a common abnormality encountered in the neonatal period, and immature platelet fraction (IPF) may be an informative indicator of thrombopoiesis; however, data on IPF in neonates are scarce. To define reference intervals (RIs) and factors affecting IPF in neonates, we measured the IPF of 533 consecutive neonates. With a multiple regression analysis of 330 newborns with normal platelet counts at birth, premature delivery, neonatal asphyxia, intrauterine infection, chromosomal abnormalities, and respiratory disorders were identified as independent factors for IPF%. The RIs of IPF% and absolute IPF value in neonates were determined to be 1.3% to 5.7% and 3.2 to 14.5×10 9 /L, respectively. On day 14 after birth, IPF% increased to twice the value at birth and thereafter returned to the previous value on day 28. Reticulocyte counts, in contrast, were the lowest at day 14. IPF% was increased in 16 thrombocytopenic patients with various clinical conditions, especially those with immune-mediated thrombocytopenia. IPF in neonates may be evaluated essentially based on the same RIs as in adults, although some precautions must be taken when evaluating IPF in neonates in the first 2 weeks of life. IPF may be useful for evaluating thrombopoiesis and thrombocytopenia in neonates.

[Large granular lymphocytic leukemia and its association with immune dysregulation]

Large granular lymphocytic (LGL) leukemia is a chronic lymphoproliferative disease of cytotoxic T cells or NK cells with LGL morphology and frequently complicated cytopenia and/or different autoimmune diseases, which often require medical interventions, although LGL leukemia itself is seldom lethal. Immunologic dysregulations in LGL leukemia contribute to the development of complications, for example, neutropenia with the involvement of Fas ligand system and, in pure red cell aplasia, which is a common complication among the patients of East Asian origin, impairing erythroid developments by cytotoxic T cells. Rheumatoid arthritis (RA) is the most prevalent nonhematological consequence, and Felty syndrome, a rare form of RA, and T-LGL leukemia have a lot in common. When patients have LGL leukemia-associated complications, immunosuppressive medication is a mainstay of treatment. Characteristic mutational features in STAT3, STAT5B, CCL22, and other genes in specific subtypes of LGL leukemia have been detected, that would be associated with immunologically mediated molecular pathogenesis in LGL leukemia, and these new findings may help in creating optimal diagnostic approaches or novel therapies for LGL leukemia.

Comparative analysis of humoral responses to BNT162b2 vaccine among patients with hematologic disorders and organ transplant recipients

Vaccination against SARS-COV-2 is considered the most promising approach to curbing the pandemic. Patients with an immunocompromised state, such as those with hematological malignancies and organ transplantation recipients, are considered more susceptible to infection, but these at-risk patients were underrepresented in early clinical trials for vaccination. Although a growing body of studies suggests that the humoral response to COVID-19 vaccination in each of these at-risk groups of patients may be suboptimal in comparison to healthy controls, a clinical and strategic information for the further comparative analysis among these groups is not fully described. The humoral responses after two doses of BNT162b2 vaccination were evaluated in a total of 187 patients either with allogeneic hematopoietic transplantation, with renal transplantation, with anti-CD20 antibody therapy, or with anti-CD38 antibody therapy, and in 66 healthy controls. The early response at one to three months after vaccination was significantly inferior among patients with renal transplantation, patients with anti-CD20 antibody therapy, and patients with anti-CD38 antibody therapy in comparison to healthy control. But the patients with allogeneic hematopoietic transplantation showed early humoral response comparable to healthy control. The late response at 6 months after vaccination was still suboptimal among patients with renal transplantation and patients with anti-CD20 therapy. Among our patient group, renal transplant recipients had the lowest antibody titers after vaccination regardless of timing of vaccination. Patients who had received allogeneic hematopoietic transplantation attained a comparable serological response to the control group especially if they are vaccinated >300 days after transplantation, but the response was suboptimal if the vaccination was within 300 days after transplantation. Our results may provide policy makers with critical information for the further stratification of at-risk groups, helping contribute to a better allocation of resources, including additional booster vaccination.

Anti-COX-2 autoantibody is a novel biomarker of immune aplastic anemia

In immune aplastic anemia (IAA), severe pancytopenia results from the immune-mediated destruction of hematopoietic stem cells. Several autoantibodies have been reported, but no clinically applicable autoantibody tests are available for IAA. We screened autoantibodies using a microarray containing >9000 proteins and validated the findings in a large international cohort of IAA patients (n = 405) and controls (n = 815). We identified a novel autoantibody that binds to the C-terminal end of cyclooxygenase 2 (COX-2, aCOX-2 Ab). In total, 37% of all adult IAA patients tested positive for aCOX-2 Ab, while only 1.7% of the controls were aCOX-2 Ab positive. Sporadic non-IAA aCOX-2 Ab positive cases were observed among patients with related bone marrow failure diseases, multiple sclerosis, and type I diabetes, whereas no aCOX-2 Ab seropositivity was detected in the healthy controls, in patients with non-autoinflammatory diseases or rheumatoid arthritis. In IAA, anti-COX-2 Ab positivity correlated with age and the HLA-DRB1*15:01 genotype. 83% of the >40 years old IAA patients with HLA-DRB1*15:01 were anti-COX-2 Ab positive, indicating an excellent sensitivity in this group. aCOX-2 Ab positive IAA patients also presented lower platelet counts. Our results suggest that aCOX-2 Ab defines a distinct subgroup of IAA and may serve as a valuable disease biomarker.

T cell clonal expansion and STAT3 mutations: a characteristic feature of acquired chronic T cell-mediated pure red cell aplasia

Acquired chronic pure red cell aplasia (PRCA) develops idiopathically or in association with other medical conditions, including T cell large granular lymphocytic leukemia (T-LGLL) and thymoma. T cell dysregulation is considered a cardinal pathogenesis of PRCA, but genetic-phenotypic associations in T cell abnormalities are largely unclear. We evaluated an extended cohort of 90 patients with acquired PRCA, including 26 with idiopathic, 36 with T-LGLL-associated and 15 with thymoma-associated PRCA, for their T cell immuno-phenotypes, clonalities and STAT3 mutations. TCR repertoire skewing of CD8⁺ T cells was detected in 37.5% of idiopathic, 66.7% of T-LGLL-associated and 25% of thymoma-associated PRCA patients, and restriction to Vβ1 was most prominent (41%). Clonalities of TCRβ or γ chain and STAT3 mutational status were statistically associated (P = 0.0398), and they were detected in all three subtypes. The overall response rate to cyclosporin A was 73.9%, without significant difference by subtypes nor STAT3 mutational status. The T cell dysregulations, such as TCR repertoire skewing with predominant Vβ1 usage, clonality and STAT3 mutations, were frequently found across the subtypes, and the close associations between them suggest that these T cell derangements reflect a common pathophysiological mechanism among these PRCA subtypes.

Identification of novel STAT5B mutations and characterization of TCRβ signatures in CD4+ T-cell large granular lymphocyte leukemia

CD4+ T-cell large granular lymphocyte leukemia (T-LGLL) is a rare subtype of T-LGLL with unknown etiology. In this study, we molecularly characterized a cohort of patients (n = 35) by studying their T-cell receptor (TCR) repertoire and the presence of somatic STAT5B mutations. In addition to the previously described gain-of-function mutations (N642H, Y665F, Q706L, S715F), we discovered six novel STAT5B mutations (Q220H, E433K, T628S, P658R, P702A, and V712E). Multiple STAT5B mutations were present in 22% (5/23) of STAT5B mutated CD4+ T-LGLL cases, either coexisting in one clone or in distinct clones. Patients with STAT5B mutations had increased lymphocyte and LGL counts when compared to STAT5B wild-type patients. TCRβ sequencing showed that, in addition to large LGL expansions, non-leukemic T cell repertoires were more clonal in CD4+ T-LGLL compared to healthy. Interestingly, 25% (15/59) of CD4+ T-LGLL clonotypes were found, albeit in much lower frequencies, in the non-leukemic CD4+ T cell repertoires of the CD4+ T-LGLL patients. Additionally, we further confirmed the previously reported clonal dominance of TRBV6-expressing clones in CD4+ T-LGLL. In conclusion, CD4+ T-LGLL patients have a typical TCR and mutation profile suggestive of aberrant antigen response underlying the disease.

[Clinical and pathophysiological features of acquired pure red cell aplasia: based on the concept of T-cell dysregulations]

Acquired pure red cell aplasia (PRCA) develops in a variety of contexts and thus, should be regarded as a syndrome. The three major subtypes of acquired PRCA are idiopathic PRCA, T cell large granular lymphocytic leukemia (T-LGLL)-associated PRCA, and thymoma-associated PRCA. Although the Japanese National Research Group on Idiopathic Bone Marrow Failure Syndromes of the Ministry of Health, Labor and Welfare of Japan has made significant contributions to our understanding of PRCA, details of its clinical characteristics, and pathophysiological mechanisms remain largely unknown. A recent epidemiological analysis using the JSH Hematologic Disease Registry revealed that approximately 100 new cases with acquired PRCA were diagnosed annually in Japan, which was higher than previously thought to be. The median age of the patients was 73 years. A prospective observational study on chronic PRCA (PRCA2016) is currently ongoing, and it may provide new clinical insights into acquired PRCA. Dysregulation of T cells has been shown to play a central role in PRCA. We studied T cell clonalities and STAT3 mutations in 90 PRCA patients and discovered that clonal T cell expansions were frequently recognized and closely associated with STAT3 mutations in the three major types of PRCA.

A novel germline GATA2 frameshift mutation with a premature stop codon in a family with congenital sensory hearing loss and myelodysplastic syndrome

GATA2 is a zinc-finger transcription factor regulating early hematopoiesis and developmental processes. Heterozygous germline mutations in GATA2 underlie a pleiotropic autosomal dominant disorder, GATA2 deficiency syndrome. The wide spectrum of its clinical features involves familial predisposition to myelodysplastic syndrome (MDS)/acute myeloid leukemia (AML) and multiorgan dysfunction, including congenital sensorineural hearing loss (CSHL). We herein report a pedigree with a novel germline frameshift mutation presenting as CSHL and familial MDS. The proband was a 46-year-old man, and his daughter also presented with an identical set of clinical syndromes. Target DNA sequencing identified a novel eight-nucleotide duplicative insertion at exon 5 (NM_032638.4:c.1126_1133dup:p.Lys378Asnfs*12)　of the GATA2 gene. RT-PCR and subcloning analysis showed that the frameshift might result in a truncated mutation with an early stop codon without interfering with the predicted splice site. The predicted mutant protein had 388 amino acids and in silico analysis showed the variant was considered deleterious. This mutation was not detected in unaffected family members. Its deleterious effect is highly likely to have portended the familial MDS and CSHL in this pedigree. Genetic testing among suspected individuals may be warranted for adequate management, including timely transplantation.

CCR4-positive peripheral T-cell lymphoma presenting as eosinophilic pneumonia and developing from prolonged pustular psoriasis

A 29-year-old woman with chronic, prolonged pustular psoriasis was admitted to our hospital because of high-grade fever and a systemic skin rash. General examination revealed a whole-body skin rash and superficial lymphadenopathy. Peripheral blood examination showed unclassified cells positive for CD3, CD4, and T-cell receptor αβ, and negative for CD20 and CD56. Soon after administration, she developed acute respiratory failure and required artificial ventilation. Bronchoalveolar lavage fluid showed increased numbers of eosinophils and abnormal lymphocytes of the same phenotype in peripheral blood and skin. She was diagnosed with eosinophilic pneumonia, and her respiratory failure was improved by corticosteroid therapy. Based on the histological findings of skin, lymph node, and bone marrow biopsies, a diagnosis of peripheral T-cell lymphoma not otherwise specified (PTCL-NOS), with positivity for CC chemokine receptor 4 was made. She received chemotherapy followed by allogeneic stem cell transplantation, which resulted in complete remission of her PTCL-NOS. She remained alive and disease-free 6 years later. This is the first reported case of PTCL-NOS developing during the clinical course of pustular psoriasis. The clinical manifestations of PTCL-NOS are complex, but an accurate diagnosis and appropriate therapy may produce a good clinical outcome in patients with PTCL-NOS.

Serum sphingomyelin species profile is altered in hematologic malignancies

Sphingomyelin (SM) plays key roles in regulating cell membrane fluidity and in intracellular signal transduction. However, little is known as to whether alterations in SM concentration or SM species distribution are linked pathological conditions. The present study examined SM concentrations and species profiles in serum taken from patients with hematologic malignancies. Serum was collected from normal subjects and from patients with B-cell lymphoma, myelodysplastic syndrome (MDS), acute myeloid leukemia (AML) and acute lymphatic leukemia/ lymphoblastic lymphoma (ALL/LBL). Serum SM species distribution was analyzed using electrospray ionization mass spectrometry/ mass spectrometry (ESI MS/MS). Serum lipids concentration were measured using enzymatic assays. Normal and hematologic malignancy sera were similar in terms of total serum SM and phosphatidylcholine (PC) concentrations and SM/PC ratio. However, all hematologic malignancy sera had lower levels of SM species containing saturated odd chain fatty acids (OCFAs) in the side chain compared to normal serum. In addition, the proportion of SM species with saturated (C20 and C22) and mono unsaturated fatty acids (C18, C20, C22) were lower in MDS patient serum compared to normal serum. The present study revealed that the serum SM species profile in patients with hematologic malignancies differed from that of normal subjects despite total serum SM and PC concentrations and SM/PC ratios being similar between the various cancer groups and the normal group.

[Recent progress in the diagnosis and management of acquired pure red cell aplasia]

Acquired pure red cell aplasia (PRCA) is characterized by normocytic anemia, reticulocytopenia, and a marked decrease in erythroid cell count in the bone marrow. PRCA develops in the context of various backgrounds, including recently recognized immune checkpoint inhibitor-associated PRCA, that need careful differential diagnoses. Besides humoral abnormalities such as major ABO-incompatible allogeneic hematopoietic stem cell transplantation-related PRCA, dysregulations of T cells have been shown. STAT3 gene mutations of cytotoxic T cells were identified in 40% of PRCA patients, which might suggest their use as novel molecular markers for PRCA. As initial management options for PRCA, red blood cell transfusion and immunosuppressive therapy (IST) drugs, such as cyclosporin, are usually selected. Roughly 80% of patients respond to IST; however, some relapse afterward or are refractory to IST. When patients with PRCA become refractory to two or three lines of IST, allogeneic hematopoietic stem cell transplantation (HCT) would become an appropriate choice, although the optimal procedures for allogeneic HCT have not been determined. A prospective study of PRCA in Japan has been ongoing since 2016 to solve the myriad clinical issues of PRCA.

Isolated splenic Mycobacterium tuberculosis complex infection in an immunocompetent individual with FDG-PET positive mass

Tuberculosis, caused by Mycobacterium tuberculosis complex, is a leading cause of mortality in the world, and 15% of the patients may present with extrapulmonary diseases, including splenic lesion. However, isolated splenic infection with M. tuberculosis complex is very rare. A 19-year-old otherwise healthy woman presented with left flank pain, revealing FDG-avid nodules in the spleen. She did not have pulmonary lesions. Histopathology of splenectomized sample showed granuloma, and subsequent PCR revealed amplification of IS6110, a genetic sequence exclusively detected in M. tuberculosis complex. A wide range of differential diagnosis of isolated splenic lesion should include M. tuberculosis infection regardless of pulmonary involvement. An elective splenectomy may be mandatory in timely manner.

Computational Fluid Dynamics Using a Porous Media Setting Predicts Outcome after Flow-Diverter Treatment

BACKGROUND AND PURPOSE

Knowledge about predictors of the outcome of flow-diverter treatment is limited. The aim of this study was to predict the angiographic occlusion status after flow-diverter treatment with computational fluid dynamics using porous media modeling for decision-making in the treatment of large wide-neck aneurysms.

MATERIALS AND METHODS

A total of 27 patients treated with flow-diverter stents were retrospectively analyzed through computational fluid dynamics using pretreatment patient-specific 3D rotational angiography. These patients were classified into no-filling and contrast-filling groups based on the O'Kelly-Marotta scale. The patient characteristics, morphologic variables, and hemodynamic parameters were evaluated for understanding the outcomes of the flow-diverter treatment.

RESULTS

The patient characteristics and morphologic variables were similar between the 2 groups. Flow velocity, wall shear stress, shear rate, modified aneurysmal inflow rate coefficient, and residual flow volume were significantly lower in the no-filling group. A novel parameter, called the normalized residual flow volume, was developed and defined as the residual flow volume normalized by the dome volume. The receiver operating characteristic curve analyses demonstrated that the normalized residual flow volume with an average flow velocity of ≥8.0 cm/s in the aneurysmal dome was the most effective in predicting the flow-diverter treatment outcomes.

CONCLUSIONS

It was established in this study that the hemodynamic parameters could predict the angiographic occlusion status after flow-diverter treatment.

T-cell large granular lymphocytic (LGL) leukemia consists of CD4+/CD8dim and CD4-/CD8+ LGL populations in association with immune thrombocytopenia, autoimmune neutropenia, and monoclonal B-cell lymphocytosis

CD3⁺/CD57⁺ T-cell large granular lymphocyte leukemia (T-LGLL) is an indolent neoplasm, exhibiting mostly CD8⁺, less frequently CD4⁺ phenotypes, and T-LGLL consisting of 2 populations with CD8⁺ and CD4⁺ phenotypes is markedly rare. An 87-year-old female was admitted under a diagnosis of immune thrombocytopenia (ITP) with a platelet count of 5.0×10⁹/L and increased number of LGL with unknown etiology. Her neutrophil count also decreased to 0.27×10⁹/L and she was positive for antineutrophil antibody. The WBC count was 2.7×10⁹/L with 34.7% LGL and flow cytometry (FCM) analysis revealed 16% CD3⁺/CD4⁺/CD8^dim/CD57⁺ and 20.9% CD3⁺/CD8⁺/CD57⁺ populations. These populations also expressed granzyme B and perforin. Circulating mononuclear cells were found to be clonal by PCR analysis of T-cell receptor β-chain gene. Serum immunofixation and bone marrow FCM analyses demonstrated 2 clonal B-cells producing IgG-λ and IgA-λ. Deep amplicon sequencing of STAT3 and STAT5B genes revealed a STAT3 R302G mutation with an allele burden of 2.6%. The thrombocytopenia and neutropenia were successfully treated by prednisolone and romiplostim with negative conversion of antineutrophil antibody. This is the first reported case of T-LGLL with dual components of CD4⁺/CD8^dim and CD4^-/CD8⁺ populations in terms of multiple comorbidities related to the respective CD8⁺ and CD4⁺ T-LGLLs.

Magnetic Resonance Imaging-negative, Rituximab-resistant Neurolymphomatosis as a Paradoxical Presentation of Relapsed Primary Adrenal Lymphoma

Primary adrenal lymphoma (PAL) is rare and known to have a predilection for central nervous system (CNS) relapse. A 70-year-old man with a 2-year history of primary aldosteronism presented because of a fever. He was hypotensive, and his adrenal glands were unequivocally enlarged. PAL was diagnosed. Despite showing an initial response to immunochemotherapy, progressive paralysis ensued. Magnetic resonance imaging findings were negative, and rituximab was ineffective. His debilitated condition hindered further chemotherapy. A postmortem examination revealed lymphoma relapse in the systemic peripheral nerves. The sequential presentation of two rare lymphomas implies that PAL might have a predilection for not only the CNS but also peripheral nerves.

Phase II study of FLAGM (fludarabine + high-dose cytarabine + granulocyte colony-stimulating factor + mitoxantrone) for relapsed or refractory acute myeloid leukemia

Given the poor prognosis of patients with relapsed/refractory acute myeloid leukemia (AML), better therapy is needed. Fludarabine enhances the efficacy of Ara-C (cytarabine) by increasing intracellular Ara-C-triphosphate. The FLAG (fludarabine, high-dose Ara-C, supported with granulocyte colony-stimulating factor) regimen has been tested for use in AML patients by other investigators. In the phase II study reported here, we evaluated the efficacy and toxicity of FLAGM therapy (FLAG with mitoxantrone), further intensified by adding mitoxantrone, based on the results of a phase I study by our group. The major endpoints were complete remission (CR) rate and early death. From June 2004 to February 2008, 41 patients (median age 52 years; range 18-64 years) were enrolled. Thirty (73% 95% CI 58-84%) patients achieved CR, which met the primary endpoint; there was a single case of early death from pneumonia. Two-year overall survival was 39.4% (95% CI 25.2-55.6%). Of those who achieved CR, 27 underwent allogeneic stem cell transplantation (SCT), and 12 SCT recipients showed long-term survival. Grade 3/4 non-hematological adverse events included infection (59%), nausea/vomiting (15%), diarrhea (7%), and elevated liver enzymes (7%). In conclusion, FLAGM is an effective and safe salvage therapy for patients with relapsed/refractory AML, and facilitated SCT for a large proportion of patients.

Successful Empiric Therapy for Postsplenectomy Sepsis with Campylobacter fetus in an Abattoir Worker with Follicular Lymphoma

Asplenia may yield an increased risk of fulminant sepsis with various pathogens. Human infection with Campylobacter fetus is rare, but it often presents with non-gastrointestinal tract infection among immunocompromised individuals. A 55-year-old abattoir worker presented with a fever. He had had splenectomy for follicular lymphoma and rituximab maintenance therapy by four months before the presentation. Blood cultures yielded C. fetus, and the administration of meropenem dissolved the bacteremia. Further maintenance therapy was withheld, and no recurrence of infection has been observed for seven years. Asplenia, occupational exposure, and/or rituximab maintenance therapy might have been precipitating factors of this rare infection.

Tumor long-axis diameter and SUVmax predict long-term responders in 90Y-ibritumomab tiuxetan monotherapy

90Y-ibritumomab tiuxetan (90Y-IT) is widely used, but the factors responsible for its optimal treatment effects are unknown. We enrolled 34 patients with relapsed indolent lymphoma treated with 90Y-IT monotherapy at Gunma University Hospital between 2003 and 2014 in the present study. Clinical data including computed tomography and 18-Fluoro-deoxyglucose positron emission tomography were retrospectively analyzed. The overall response rate and complete response rate were 91% and 82%, respectively. The median progression-free survival (PFS) and overall survival were 32 months and not reached, respectively. In univariate analysis, tumor long-axis diameter ≤ 2.5 cm, maximum standardized uptake value (SUVmax) ≤ 6.5, localized disease, normal levels of serum soluble interleukin-2 receptor, and the number of involved nodal sites ≤ 3 immediately prior to 90Y-IT were associated with median PFS greater than 6 years. However, in multivariate analysis, only tumor long-axis diameter ≤ 2.5 cm and SUVmax ≤ 6.5 affected PFS [hazard ratio (HR) 0.130, P = 0.0021 and HR 0.283, P = 0.0311, respectively]. Patients with only one prior regimen needed less granulocyte colony-stimulating factor and platelet transfusion. Thus, 90Y-IT treatment should be considered for patients with indolent lymphoma in first relapse who have tumor long-axis diameter ≤ 2.5 cm and SUVmax ≤ 6.5.

The Largest Isoform of Platelet Membrane Glycoprotein Iba Is Commonly Distributed in Eastern Asian Populations

Platelet membrane glycoprotein Iba has at least two polymorphisms which affect phenotype. One is the dimorphism at codon 145, and the other is a molecular weight polymorphism due to variable numbers of tandem repeats (TR) in the macroglycopeptide region. These two polymorphisms are in linkage disequilibrium. The frequencies of these polymorphisms differ considerably depending on race, and the largest variant with four TR is almost exclusively present in the Japanese population. We examined the genotypes of HPA-2 and TR polymorphism in three different races from Eastern Asia; the Japanese (n = 103), Korean (n = 101) and Chinese population (n = 177). The gene frequency of HPA-2 differed significantly among these three populations. Among HPA-2b-positive individuals, the A isoform with four TR and B with three TR were present in all three populations and A dominated over B. Individuals homozygous for the A isoform were found in both Japanese and Korean populations. These findings indicate that the largest haplotype is common in the Eastern Asian region.

Serum Thrombopoietin (c-MpI Ligand) Levels in Patients with Liver Cirrhosis

To clarify the role of c-Mpl ligand (thrombopoietin: TPO) in liver cirrhosis (LC), we examined serum TPO levels (sTPO) in patients with LG (N = 44), chronic hepatitis (CH; N = 13) and healthy controls (N = 41) by an enzyme-linked immunosorbent assay. Although platelet counts of all LC patients (89 ± 59 × 109/1; mean ± SD) were lower than those of controls and CH patients, sTPO levels in LC patients (1.23 ± 0.51 fmol/ml) were the same as those in controls (1.22 ± 0.37) and CH patients (1.18 ± 0.36). Platelet counts were significantly higher in splenectomized patients than in unsplenectomized patients, but the sTPO level did not differ between these two groups. In LC patients, the sTPO level was not correlated with the platelet count, but was correlated with prothrombin time, activated partial thromboplastin time, and total bilirubin, indicating that production of TPO in the liver decreases slightly with the development of liver dysfunction. Our findings suggest that production of TPO is maintained in LC patients and their thrombocytopenia is not due to a defect in platelet production.

Regulation of Serum Thrombopoietin Levels by Platelets and Megakaryocytes in Patients with Aplastic Anaemia and Idiopathic Thrombocytopenic Purpura

To clarify the regulatory mechanism of thrombopoietin (TPO, c-Mpl ligand) in chronic thrombocytopenic conditions, we determined TPO levels in the sera of patients with aplastic anaemia (AA; n = 26) and idiopathic thrombocytopenic purpura (ITP; n = 32) by an enzyme-linked immunosorbent assay. Despite a similarity in platelet counts, serum TPO levels in the AA group were markedly higher than those in the ITP group: 20.41 ± 9.71 f mol/ml (mean ± SD) and 1.66 ± 0.55 f mol/ml, respectively, both of which were significantly elevated compared to normal subjects (n = 41; 1.22 ± 0.37). In both groups, serum TPO level showed an inverse correlation with the platelet count. We determined the megakaryocyte volume using bone marrow clot section and found that it was markedly small in the AA group; while in the ITP group it was augmented with a correlation to serum TPO level. Our findings suggest that TPO levels may be regulated not only by platelets but also megakaryocytes in AA and ITP.

Breakthrough Candida guilliermondii (Meyerozyma guilliermondii) fungemia after cord blood transplantation for extranodal NK-cell lymphoma with azole prophylaxis

Fluconazole (FLCZ) is an azole antifungal agent and it has shown excellent clinical activities in suppressing fungemia with Candida albicans after hematopoietic stem cell transplantation. Increased administration of prophylactic FLCZ seems to have given rise to the relatively higher incidence of more resistant Candida non-albicans infection. We present a case with a rare breakthrough fungemia with C. guilliermondii after cord blood transplantation for Extranodal NK cell Lymphoma, nasal type (ENKL), during antifungal prophylaxis with FLCZ. High level of caution is needed for the breakthrough, especially after long-term azole administration.

[Successful treatment of X-linked sideroblastic anemia with ALAS2 R452H mutation using vitamin B6]

A 45-year-old man presented with fatigue and pain in the finger joints. Despite having a history of suspected sideroblastic anemia since the age of 18 years, he had not been followed up for years. Upon presentation, laboratory data revealed microcytic anemia and elevated serum ferritin levels. In addition, ringed sideroblasts were increased in the bone marrow. A liver biopsy revealed hemochromatosis and cirrhosis. Furthermore, genetic analysis revealed that he harbored the ALAS2 R452H mutation, leading to the diagnosis of X-linked sideroblastic anemia (XLSA). Accordingly, oral folate or vitamin (Vit) B₁₂ was administered, but his anemia did not respond. However, his hemoglobin level increased from 7 to 11 g/dl with an additional prescription of oral VitB₆, which facilitated the patient to undergo phlebotomy to ameliorate organ dysfunctions caused by iron overload. Previous research has revealed that ALAS2 R452 mutations confer poor responses to VitB₆ therapy. Hence, accrual of patients with an unexpectedly better response, which was observed in our case, may help elucidate the pathogenesis of and therapies for XLSA.

Aggressive natural killer-cell leukemia mutational landscape and drug profiling highlight JAK-STAT signaling as therapeutic target

Aggressive natural killer-cell (NK-cell) leukemia (ANKL) is an extremely aggressive malignancy with dismal prognosis and lack of targeted therapies. Here, we elucidate the molecular pathogenesis of ANKL using a combination of genomic and drug sensitivity profiling. We study 14 ANKL patients using whole-exome sequencing (WES) and identify mutations in STAT3 (21%) and RAS-MAPK pathway genes (21%) as well as in DDX3X (29%) and epigenetic modifiers (50%). Additional alterations include JAK-STAT copy gains and tyrosine phosphatase mutations, which we show recurrent also in extranodal NK/T-cell lymphoma, nasal type (NKTCL) through integration of public genomic data. Drug sensitivity profiling further demonstrates the role of the JAK-STAT pathway in the pathogenesis of NK-cell malignancies, identifying NK cells to be highly sensitive to JAK and BCL2 inhibition compared to other hematopoietic cell lineages. Our results provide insight into ANKL genetics and a framework for application of targeted therapies in NK-cell malignancies.

Aggressive natural killer-cell leukemia (ANKL) has few targeted therapies. Here ANKL patients are reported to harbor STAT3, RAS-MAPK pathway, DDX3X and epigenetic modifier mutations; and drug sensitivity profiling uncovers the importance of the JAK-STAT pathway, revealing potential ANKL therapeutic targets.

Severe Infection of Pseudomonas aeruginosa during Eculizumab Therapy for Paroxysmal Nocturnal Hemoglobinuria

Eculizumab is the complement inhibitor administered to ameliorate intravascular hemolysis in paroxysmal nocturnal hemoglobinuria. Whether or not the inhibitory mechanism may also increase the susceptibility to non-Neisserial infection is unclear. A 73-year old woman presented with bacteremia, cholecystitis and liver abscess with Pseudomonas aeruginosa. Although she had been neutropenic for 21 years, she had no history of severe infection before eculizumab had been administered. The infection with P. aeruginosa was successfully controlled with antibiotics, granulocyte colony-stimulating factor and cholecystectomy. The present case might be representative of less common bacterial infections than Neisseria spp. among patients treated with eculizumab.

Aggressive NK-Cell Leukemia

Aggressive NK cell leukemia (ANKL) is a rare malignant lymphoproliferative disorder of mature NK cells closely associated with Epstein-Barr virus (EBV) and more common in East Asia than in other areas. Significant variations exist in the morphology of ANKL tumor cells, from typical large granular lymphocyte morphology to highly atypical features with basophilic cytoplasm containing azurophilc granules. The main involved sites are hepatosplenic lesions, bone marrow and peripheral blood, and nasal or skin lesions are infrequent. A fever and liver dysfunction with an often rapidly progressive course are the main clinical symptoms, including hemophagocytic syndrome and disseminated intravascular coagulation. Although the outcome had been dismal for decades, with a median survival of less than three months, the introduction of combined chemotherapy including L-asparaginase and allogeneic hematopoietic cell transplantation has helped achieve a complete response and potential cure for some patients. With the advent of next-generation sequencing technologies, molecular alterations of ANKL have been elucidated, and dysfunctions in several signaling pathways, including the JAK/STAT pathway, have been identified. Novel target approaches to managing these abnormalities might help improve the prognosis of patients with ANKL.

A Missense Mutation (Tyr88 to Cys) in the Platelet Membrane Glycoprotein Ibβ Gene Affects GPIb/IX Complex Expression

This study examined the molecular basis of a missense mutation of the platelet glycoprotein (GP) Ibβ gene in two families. In the propositus with a novel form of Bernard-Soulier syndrome (BSS) from Family I, only GPIbα was detectable in reduced amounts on platelet surfaces by flow cytometry. There were no GPIX or GPIbβ found by immunoblotting. DNA sequencing analysis showed a homozygous mutation in the GPIbβ gene which changed Tyr (TAC) to Cys (TGC) at residue 88. Her parents were heterozygous for Tyr88Cys in the GPIbβ gene. In transient transfection studies on 293T cells, both Tyr88Cys and Tyr88Ala mutations suppressed the expression of GPIb/IX complexes. In addition, Tyr88Cys GPIbβ mutation was found to exert a dominant negative effect on the GPIb expression.

Five individuals from Family II, four of whom reported elsewhere as having giant platelet disorders with normal aggregation (BLOOD, 1997; 89: 2404) and one newly analyzed in this study, were heterozygous for Tyr88Cys in the GPIb gene. Microsatellite analysis of chromosome 22 showed a common haplotype in 8 of the individuals with Tyr88Cys mutations in Families I and II. Tyr88 in the GPIbβ gene plays a significant role in the GPIb/IX expression; the defect causes BSS in a homozygous form and possibly giant platelets in a heterozygous form.

Fibrinogen Matsumoto III: a Variant with γ275 Arg→Cys (CGC→TGC) – Comparison of Fibrin Polymerization Properties with those of Matsumoto I (γ364 Asp→His) and Matsumoto II (γ308 Asn→Lys)

Fibrinogen Matsumoto III (M-III) is a dysfibrinogen identified in a 66-year-old woman with rectal cancer. The fibrinogen level determined by the thrombin-time method was markedly decreased in preoperative coagulation tests of her plasma. Three fibrinogen polypeptide-chain gene fragments from the proposita were amplified by the polymerase chain reaction method, then sequenced. The triplet CGC encoding the amino acid residue γ275 was replaced by TGC, resulting in the substitution of Arg→Cys. There have been previous reports of nine families with the same alteration, nine families with an Arg→His variant and one family with an Arg→Ser variant in this residue, which has been shown to be one of the most important amino acids in the ’D:D’ interaction site. In addition, there are three silent mutations in the Aα-chain gene and two mutations in the intron of the Bβ-chain and the γ-chain gene. However, none of these mutations is thought to be the cause of the dysfunctional fibrinogen. The thrombin-catalyzed fibrin polymerization in the presence of 1 mM Ca ions was markedly delayed in purified M-III. Its lag period was longer than those of Matsumoto II (M-II; γ308Asn→Lys) and Matsumoto I (M-I; γ364Asp→His). γ364Asp is one of the most important residues in the polymerization pocket of the ’D:E’ interaction site and γ308Asn is located in the vicinity of a high affinity Ca2+ binding site in the D-domain, γ311-336. The maximum slope of the polymerization curve for M-III was about 4-fold steeper than that for M-I but less steep than that for M-II. These results may suggest that the tertiary structure of the polymerization pocket plays a more important role in the lateral aggregation of protofibrils than that of the ’D:D’ interaction site.

Exogenous Magnesium Chloride Reduces the Activated Partial Thromboplastin Times of Lupus Anticoagulant-Positive Patients

The activated partial thromboplastin time (APTT) assay is a basic hemostatic assay based on the time it takes for clots to form in plasma samples after the addition of calcium chloride. It is used to screen for various coagulation disorders. Several previous reports have suggested that magnesium (Mg) might contribute to coagulation reactions by binding to specific coagulation proteins. We investigated the effects of Mg on the APTT. In healthy controls, the APTT was significantly prolonged in proportion to the increase in the concentration of magnesium chloride in the range from 2.1 to 16.7 mmol/L. Among eight samples from patients with various disorders that exhibited prolonged APTT, two samples demonstrated shorter APTT when Mg was added, both of which were from patients that were positive for lupus anticoagulant. When we examined 206 clinical APTT samples, we found that Mg shortened the APTT of two samples. These two samples were also from lupus anticoagulant-positive patients (p-value: <0.003). Our findings regarding the unique effects of exogenous Mg on the APTT of lupus anticoagulant-positive patients might shed light on the role of Mg in APTT assays and lead to the development of a novel screening method for lupus anticoagulant.

Donor Left-Sided Heptectomy by Use of the Real-Time Moving Windows Method With 8-Centimeter Transverse Skin Incision

BACKGROUND

In this study, we demonstrated our new device for open donor liver surgery with left-sided heptectomy by use of the real-time moving windows (RTMW) method with 8-cm transverse skin incision for living donors from the viewpoints of cosmetic, economic, and safety procedures.

METHODS

After the upper abdominal 8-cm transverse skin incision was made, the subcutaneous area was exfoliated and the reverse T-shaped-abdominal incision was made, as in open surgery. After that, the 2 Kent hooks for the upper region and the 2 surgical arms for the lower region were placed. The operative fields of hepatic vein, hepatic hilus, and common hepatic artery were explored, respectively, by use of the RTMW method with the use of the 4 surgical hooks. Hepatic parenchymal dissection was carried out with the use of CUSA and laparosonic coagulating shears. Manipulations of 3 hepatic vessels and the hepatic duct were done by the usual procedure of open surgery.

RESULTS

This operative procedure could be performed without laparoscopic techniques. The operative time was 7 hours, without blood transfusion. The operative course was uneventful, and the patient was discharged on postoperative day 11.

CONCLUSIONS

Our RTMW method for donor left-sided hepatectomy is considered to be a useful operative procedure from the viewpoints of donor safety, cosmetic advantage, and cost performance.

Palate and alveolar ridge development in predental infants: a longitudinal study

AIM

To investigate the developmental process of palate morphology, including the alveolar ridge, in healthy infants for the predental period of 7 months from immediately after birth.

METHODS

The subjects were 32 healthy infants. Four or more dental casts were taken of each subject from immediately after birth until 7 months, for a total of 144 dental casts. Twelve characteristics were then measured in order to morphologically study the subjects' palate development. Principal component analysis (PCA) was performed to investigate morphological changes in the palatal vault.

RESULTS

The 12 characteristics were classified into either the alveolar ridge characteristics group, which determined the size of the alveolar ridge, or the palate characteristics group, which determined palate morphology, with each group showing different growth patterns. The characteristics of width and length increased with age in the alveolar ridge characteristics group; this correlation was maintained throughout the predental period. Meanwhile, in the palate characteristics group, the characteristics showed major developmental changes in the first 2 to 3 months after birth, but the changes were subsequently fewer from 3 to 7 months. The PCA of the palatal vault showed that the first principal component increased until 3 months but subsequently ceased to change.

CONCLUSIONS

In predental infants, growth patterns of palate morphology differed according to their characteristics. There were major developmental changes in the palate during the first 3 months after birth. The study findings suggest that palate growth in the first half of the predental period may affect subsequent palate growth.

[Recent progress of diagnosis and treatment in NK cell neoplasms]

Aggressive natural killer cell leukemia (ANKL) is a malignant disorder of mature NK cells that is relatively common in East Asia. It is associated with Epstein-Barr virus in more than 80% of patients. The median survival is not more than three months after diagnosis. In a recent survey of 34 cases with ANKL, the median patient age was 40 years and the age distribution followed a bimodal pattern. Morphologically, the ANKL cells varied from large granular lymphocytes to atypical cells with pleomorphic-like appearances. Clinical characteristics include fever, liver dysfunction, hemophagocytic syndrome, and a rapidly progressive course. In one third of patients, tumor cells in peripheral blood or the bone marrow are below 20% at initial presentation, which might lead to diagnostic delay. L-asparaginase-based chemotherapy plus allogeneic hematopoietic stem cell transplantation (HSCT) is a potential therapeutic option with curative intent.  As for extranodal NK/T cell lymphoma, nasal type, HSCT could be anticipated to provide survival benefit or a chance of cure for patients in clinical stage II to IV with complete remission at transplantation. However, the optimal stem cell source, timing of transplantation, and preconditioning regimen require further elucidation.

Prognostic significance of pleural or pericardial effusion and the implication of optimal treatment in primary mediastinal large B-cell lymphoma: a multicenter retrospective study in Japan

The prognosis of patients with primary mediastinal large B-cell lymphoma has improved over recent years. However, the optimal treatment strategy including the role of radiotherapy remains unknown. We retrospectively analyzed the clinical outcomes of 345 patients with newly diagnosed primary mediastinal large B-cell lymphoma in Japan. With a median follow up of 48 months, the overall survival at four years for patients treated with R-CHOP (n=187), CHOP (n=44), DA-EPOCH-R (n=9), 2(nd)- or 3(rd)-generation regimens, and chemotherapy followed by autologous stem cell transplantation were 90%, 67%, 100%, 91% and 92%, respectively. Focusing on patients treated with R-CHOP, a higher International Prognostic Index score and the presence of pleural or pericardial effusion were identified as adverse prognostic factors for overall survival in patients treated with R-CHOP without consolidative radiotherapy (IPI: hazard ratio 4.23, 95% confidence interval 1.48-12.13, P=0.007; effusion: hazard ratio 4.93, 95% confidence interval 1.37-17.69, P=0.015). Combined with the International Prognostic Index score and the presence of pleural or pericardial effusion for the stratification of patients treated with R-CHOP without radiotherapy, patients with lower International Prognostic Index score and the absence of effusion comprised approximately one-half of these patients and could be identified as curable patients (95% overall survival at 4 years). The DA-EPOCH-R regimen might overcome the effect of these adverse prognostic factors. Our simple indicators of International Prognostic Index score and the presence of pleural or pericardial effusion could stratify patients with primary mediastinal large B-cell lymphoma and help guide selection of treatment.

STAT3 gene mutations and their association with pure red cell aplasia in large granular lymphocyte leukemia

Large granular lymphocyte leukemia (LGL L) has been morphologically characterized as a group of lymphoproliferative diseases that include T-cell large granular lymphocytic leukemia (T-LGL L) and chronic lymphoproliferative disorders of natural killer cells (CLPD-NK). We investigated mutations in the Src homology 2 (SH2) domain of the signal transducer and activator of transcription 3 (STAT3) gene in Asian cohorts of T-LGL L and CLPD-NK (n = 42 and 11, respectively). Two mutations, Y640F and D661Y, were identified using direct sequencing or allele-specific (AS) PCR. Y640F and D661Y mutations were found in seven and 18 patients, respectively. Two patients were positive for both mutations. Frequencies of STAT3 mutations in T-LGL L and CLPD-NK were 47.6% and 27.2%, respectively. Pure red cell aplasia (PRCA) was associated with the mutations (P = 0.005). The mutations were persistently found at stable levels in some patients after more than 5 years using AS-quantitative PCR. The results of the present study indicate that the SH2 domain of the STAT3 gene is frequently mutated in Asian T-LGL L and CLPD-NK, and that PRCA is closely correlated with the mutations.

Candidate gene analysis using genomic quantitative PCR: identification of ADAMTS13 large deletions in two patients with Upshaw-Schulman syndrome

Direct sequencing is a popular method to discover mutations in candidate genes responsible for hereditary diseases. A certain type of mutation, however, can be missed by the method. Here, we report a comprehensive genomic quantitative polymerase chain reaction (qPCR) to complement the weakness of direct sequencing. Upshaw-Schulman syndrome (USS) is a recessively inherited disease associated with severe deficiency of plasma ADAMTS13 activity. We previously analyzed ADAMTS13 in 47 USS patients using direct sequencing, and 44 of them had either homozygous or compound heterozygous mutations. Then, we sought to reveal more extensive defects of ADAMTS13 in the remaining three patients. We quantified copy numbers of each ADAMTS13 exon in the patients by using genomic qPCR. Each primer pair was designed to contain at least one of the two primers used in direct sequencing, to avoid missing any exonic deletions. The qPCR demonstrated heterozygous loss of exons 7 and 8 in one patient and exon 27 in the other, and further analysis revealed c.746_987+373del1782 and c.3751_3892+587del729, respectively. Genomic qPCR provides an effective method for identifying extensive defects of the target genes.

Screening tests using serum tissue transglutaminase IgA may facilitate the identification of undiagnosed celiac disease among Japanese population

The prevalence of celiac disease (CD) among Japanese population has been unknown, whereas it has been increasingly recognized in the US and in the European countries. The aim of the present study is to identify possible cases with CD among Japanese population and clarify the relevance of screening for the disease. We conducted a serologic screening for the disease among 710 Japanese patients and 239 healthy volunteers at a local tertiary teaching hospital, using an anti-tissue transglutaminase IgA (TTG-IgA) test, and histological examination of the small intestines from the TTG-IgA positive subjects. There were no TTG-IgA positive sera among the healthy volunteers. Twenty of the patients (2.8%), including eight with malignant lymphoma, were tested positive for TTG-IgA. The histological examination of the eleven patients among those with positive TTG-IgA, seven showed villous atrophy and partial lymphocytes infiltration in the mucosa, which could be compatible to mucosal changes observed in CD. Five of them had non-Hodgkin lymphoma in the gastrointestinal tracts. Serologic tests using TTG-IgA might be relevant to screen for those with undiagnosed CD among Japanese population.

Richter transformation in the brain from chronic lymphocytic leukemia

Richter syndrome (RS) involves the development of an aggressive lymphoma in patients with chronic lymphocytic leukemia (CLL). Diffuse large B-cell lymphoma (DLBCL) is the most common type of RS. Extranodal RS occasionally occurs; however, isolated lesions in the central nervous system (CNS) of RS are rarely seen and the features have not been well described. We describe a Japanese patient who developed isolated involvements of the parenchyma of the CNS as a manifestation of RS two years after the initial diagnosis of CLL. DLBCL in the cerebrum was confirmed to be clonally related to the CLL cells by immunoglobulin heavy chain (IGH) gene analysis, utilizing the identical VH-D-J regions with additional mutations in the IGH variable region.