Outcomes of transplant-eligible patients with myelodysplastic syndrome with excess blasts registered in an observational study: The JALSG-CS11-MDS-SCT.

Allogeneic hematopoietic stem cell transplantation (allo-SCT) is the sole curative therapy for myelodysplastic syndrome (MDS). However, whether bridging therapy (BRT) including azacitidine (AZA) and combination chemotherapy (CCT) prior to allo-SCT should be performed is unclear. We analyzed BRT and the outcomes of patients with myelodysplastic syndrome with excess blasts (MDS-EB) who were ≤ 70 years old at the time of registration for a prospective observational study to clarify the optimal allo-SCT strategy for high-risk MDS. A total of 371 patients were included in this study. Among 188 patients (50.7%) who were considered for allo-SCT, 141 underwent allo-SCT. Among the patients who underwent allo-SCT, 64 received AZA, 29 received CCT, and 26 underwent allo-SCT without BRT as the initial treatment. Multivariate analysis identified BRT as an independent factor influencing overall survival (AZA vs. without BRT, hazard ratio [HR] 3.33, P = 0.005; CCT vs. without BRT, HR 3.82, P = 0.003). In multivariate analysis, BRT was independently associated with progression-free survival (AZA vs. without BRT: HR, 2.23; P = 0.041; CCT vs. without BRT: HR, 2.94; P = 0.010). Transplant-eligible patients with MDS-EB should undergo allo-SCT when clinically acceptable, and upfront allo-SCT without BRT may be superior to AZA or CCT.

The effectiveness of immunosuppressive therapy in patients with aplastic anaemia secondary to chemoradiotherapy for cancers.

The outcome of immunosuppressive therapy (IST) and prognosis in patients with aplastic anaemia (AA) secondary to chemotherapy or radiotherapy for cancers remains unknown. A total of 43 of 2559 patients with AA referred to our hospital had previously received chemoradiotherapy for various types of solid tumours (n = 25) or haematological malignancies (n = 18). Their cancer status was complete remission (CR) in 27, non-CR in 13, and unknown in three. Small populations of glycosylphosphatidylinositol-anchored protein-deficient [GPI(-)] granulocytes were detected in 16 patients (37·2%). Of 18 patients who were treated with IST, 50% improved regardless of the presence of GPI(-) cells. The overall survival (OS) rate was significantly higher in patients with a history of solid tumours patients than in those of haematological malignancies (median OS, 87 vs. 11 months, P = 0·0003), and in patients treated with IST than in those of untreated patients (median OS, 115 vs. 20 months, P = 0·028). Cancer aggravation occurred in two of four patients who were treated with IST while in non-CR of their original cancers. Progression to myelodysplastic syndromes was observed in two patients not possessing GPI(-) cells. IST should thus be considered for patients with AA secondary to chemoradiotherapy for cancers, particularly when their original solid tumours are in CR.

Identification of an HLA class I allele closely involved in the autoantigen presentation in acquired aplastic anemia.

To identify HLA alleles closely involved in the autoantigen presentation in acquired aplastic anemia (AA), we studied the HLA allelic loss frequencies of 312 AA patients, including 43 patients with loss of heterozygosity of 6p chromosome (6pLOH). An analysis of the HLA alleles contained in the lost haplotype revealed HLA-B*40:02 to be the most frequently lost allele. When we examined 28 AA (12 6pLOH[+] and 16 6pLOH[-]) patients with HLA-B*40:02 for the presence of leukocytes lacking HLA-B4002 (B4002-) using a new monoclonal antibody specific to this allele, B4002- granulocytes were detected not only in all 6pLOH(+) patients but also in 9 (56%) of the 16 6pLOH(-) patients. Furthermore, 10 (83%) of the 12 6pLOH(+) patients possessed 1.0% to 78% B4002- granulocytes that retained the HLA-A allele on the same haplotype (B4002-A+), suggesting the frequent coexistence of granulocytes that underwent mutations restricted to HLA-B*40:02 with 6pLOH(+) (B4002-A-) granulocytes. Deep sequencing of the HLA-B*40:02 of sorted B4002-A+ granulocytes revealed various somatic mutations, such as frameshift, nonsense, and splice site mutations, in all 15 patients studied. Surprisingly, missense mutations in the α-3 domain of HLA-B*40:02 that are not involved in the antigen presentation were detected exclusively in the B4002+ granulocytes of 3 patients possessing B4002- granulocytes. The markedly high prevalence of leukocytes lacking HLA-B4002 as a result of either 6pLOH or structural gene mutations, or both, suggests that antigen presentation by hematopoietic stem/progenitor cells to cytotoxic T cells via the HLA-B allele plays a critical role in the pathogenesis of AA.

[Mild hemophilia A diagnosed in an adult patient on the occasion of post-operative bleeding following a second knee surgery].

A 48-year-old male underwent an osteosynthesis surgery for right patellar fracture without bleeding episodes around the surgery. After 7 months, he presented with a bleeding episode after a nail extraction surgery from his knee joint. He was diagnosed with mild hemophilia A after his second surgery. The patient's clinical course suggested that he had mild hemophilia A, although he had a past surgical history without any bleeding episodes. Early diagnosis is important in patients with mild hemophilia A because bleeding episodes complicated with surgery can be prevented by the administration of prophylactic replacement therapy.

Immune-Mediated Hematopoietic Failure after Allogeneic Hematopoietic Stem Cell Transplantation: A Common Cause of Late Graft Failure in Patients with Complete Donor Chimerism.

Late graft failure (LGF) without evidence of residual recipient cells is a serious complication after allogeneic hematopoietic stem cell transplantation (allo-SCT) and often requires stem cell infusion from the same donor when the patient fails to respond to conventional therapies. We screened the peripheral blood (PB) of 14 patients who developed donor-type LGF at 2 to 132 months after allo-SCT for the presence of the markers for immune-mediated bone marrow (BM) failure. Increased glycosylphosphatidyl inositol-anchored protein-deficient (GPI-AP-) leukocytes, which accounted for .009% to 0.147% of the total granulocytes, were detected in 5 patients (severe aplastic anemia, n = 2; follicular lymphoma, n = 1; acute lymphoblastic leukemia, n = 1; myelodysplastic syndromes; n = 1) and 4.7% to 81.2% HLA-allele-lacking leukocytes (HLA-LLs) were detected in 2 patients (acute myelogenous leukemia, n = 1; and myelodysplastic syndromes, n = 1). Three of the 5 patients with increased GPI-AP- leukocytes were treated with antithymocyte globulin (ATG), and 2 patients achieved transfusion independence. These results suggest that immune mechanisms that are similar to acquired aplastic anemia underlie condition of approximately one-half of the patients with donor-type LGF, and that in patients with increased GPI-AP- cells, donor-derived hematopoiesis may be restored by ATG therapy alone without donor stem cell infusion.

[Successful treatment with total cranial irradiation for central nervous system involvement of Langerhans cell sarcoma during chemotherapy].

Langerhans cell sarcoma (LCS) is an extremely rare neoplasm of Langerhans cell origin characterized by systemic involvement and a poor prognosis. There are, however, few reports of LCS with central nervous system involvement. We experienced a patient with LCS recurrence in the brain that appeared during systemic chemotherapy. The brains lesions eventually responded to total cranial irradiation. A 60-year-old female presented with systemic lymphadenopathy. LCS was diagnosed based on neck lymph node biopsy findings. Two cycles of ESHAP induced marked regression of her lymphadenopathy, but FDG-PET/CT scan revealed new lesions in the central nervous system and her disorientation gradually worsened. We administered 37.5 Gy of total cranial irradiation which improved her consciousness and shrank the brain tumors as demonstrated by MRI. The patient's clinical course indicates that radiation therapy may be effective for central nervous system involvement of LCS even if the lesion is resistant to systemic chemotherapy.

Cryoglobulinemia vasculitis associated with adult-onset Still's disease.

Key Clinical Message: The present case indicates that cryoglobulinemia vasculitis should be considered in the differential diagnosis of purpura in patients with adult-onset Still's disease (AOSD). Abstract: The presence of purpura is suggested in adult-onset Still's disease (AOSD) hematological complications of hemophagocytic syndrome, disseminated intravascular coagulation, or thrombotic microangiopathy. We herein report a case of AOSD complicated by cryoglobulinemia vasculitis presenting with purpura.

HLA Class I Allele Loss and Bone Marrow Transplantation Outcomes in Immune Aplastic Anemia.

In patients with immune-mediated acquired aplastic anemia (AA), HLA class I alleles often disappear from the surface of hematopoietic progenitor cells, potentially enabling evasion from cytotoxic T lymphocyte-mediated pathogenesis. Although HLA class I allele loss has been studied in AA patients treated with immunosuppressive therapy (IST), its impact on allogeneic bone marrow transplantation (BMT) has not been thoroughly investigated. The purpose of this study was to evaluate the clinical implications of HLA class I allele loss in patients with acquired AA undergoing allogeneic BMT. The study enrolled acquired AA patients who underwent initial BMT from unrelated donors through the Japan Marrow Donor Program between 1993 and 2011. The presence of HLA class I allele loss due to loss of heterozygosity (HLA-LOH) was assessed using pretransplantation blood DNA and correlated with clinical data obtained from the Japanese Transplant Registry Unified Management Program. A total of 432 patients with acquired AA were included in the study, and HLA-LOH was detected in 20 of the 178 patients (11%) available for analysis. Patients with HLA-LOH typically presented with more severe AA at diagnosis (P = .017) and underwent BMT earlier (P < .0001) compared to those without HLA-LOH. They also showed a slight but significant recovery in platelet count from the time of diagnosis to BMT (P = .00085). However, HLA-LOH status had no significant effect on survival, engraftment, graft failure, chimerism status, graft-versus-host disease, or other complications following BMT, even when the 20 HLA-LOH+ patients were compared with the 40 propensity score-matched HLA-LOH- patients. Nevertheless, patients lacking HLA-A*02:06 or HLA-B*40:02, the alleles most frequently lost and associated with a better IST response, showed higher survival rates compared to those lacking other alleles, with estimated 5-year overall survival (OS) rates of 100% and 44%, respectively (P = .0042). In addition, in a specific subset of HLA-LOH- patients showing clinical features similar to HLA-LOH+ patients, the HLA-A*02:06 and HLA-B*40:02 allele genotypes correlated with better survival rates compared with other allele genotypes, with estimated 5-year OS rates of 100% and 43%, respectively (P = .0096). However, this genotype correlation did not extend to all patients, suggesting that immunopathogenic mechanisms linked to the loss of certain HLA alleles, rather than the HLA genotypes themselves, influence survival outcomes. The survival benefit associated with the loss of these two alleles was confirmed in a multivariable Cox regression model. The observed correlations between HLA loss and the pretransplantation clinical manifestations and between loss of specific HLA class I alleles and survival outcomes in AA patients may improve patient selection for unrelated BMT and facilitate further investigations into the immune pathophysiology of the disease.

Leukemic phase as the initial presentation of ALK-positive anaplastic large-cell lymphoma complicated by lactic acidosis.

The leukemic phase of ALK-positive anaplastic large cell lymphoma (ALCL) is reported to have a poor prognosis. We, herein, report a rare case of the common type of ALK-positive ALCL complicated by lactic acidosis.

Successful bridging therapy with tirabrutinib before ASCT for relapsed primary DLBCL of the CNS complicated with PBC, cirrhosis, and pancytopenia.

The optimal therapy for relapsed primary diffuse large B-cell lymphoma (DLBCL) of the central nervous system (CNS) remains unclear. We herein report a case of relapsed primary DLBCL of the CNS complicated with primary biliary cholangitis, cirrhosis, and pancytopenia that was successfully treated with bridging therapy with tirabrutinib before autologous hematopoietic stem cell transplantation (ASCT). Tirabrutinib is well tolerated and effective for relapsed primary DLBCL of the CNS with comorbidities, including cirrhosis and pancytopenia. Tirabrutinib is a promising option as bridging therapy before ASCT.

The GPI-anchored protein CD109 protects hematopoietic progenitor cells from undergoing erythroid differentiation induced by TGF-ß.

Although a glycosylphosphatidylinositol-anchored protein (GPI-AP) CD109 serves as a TGF-ß co-receptor and inhibits TGF-ß signaling in keratinocytes, the role of CD109 on hematopoietic stem progenitor cells (HSPCs) remains unknown. We studied the effect of CD109 knockout (KO) or knockdown (KD) on TF-1, a myeloid leukemia cell line that expresses CD109, and primary human HSPCs. CD109-KO or KD TF-1 cells underwent erythroid differentiation in the presence of TGF-ß. CD109 was more abundantly expressed in hematopoietic stem cells (HSCs) than in multipotent progenitors and HSPCs of human bone marrow (BM) and cord blood but was not detected in mouse HSCs. Erythroid differentiation was induced by TGF-ß to a greater extent in CD109-KD cord blood or iPS cell-derived megakaryocyte-erythrocyte progenitor cells (MEPs) than in wild-type MEPs. When we analyzed the phenotype of peripheral blood MEPs of patients with paroxysmal nocturnal hemoglobinuria who had both GPI(+) and GPI(-) CD34+ cells, the CD36 expression was more evident in CD109- MEPs than CD109+ MEPs. In summary, CD109 suppresses TGF-ß signaling in HSPCs, and the lack of CD109 may increase the sensitivity of PIGA-mutated HSPCs to TGF-ß, thus leading to the preferential commitment of erythroid progenitor cells to mature red blood cells in immune-mediated BM failure.

Imaging findings of a case of intravascular large B-cell lymphoma with cardiac involvement.

Intravascular large B-cell lymphoma (IVLBCL) is a very rare subtype of malignant lymphoma that is difficult to diagnose. Cases of myocardial infarction caused by IVLBCL are even rarer. Herein, we report a case presenting with heart failure and delayed enhancement in the hypokinetic cardiac septum on contrast-enhanced cardiac magnetic resonance imaging. Myocardial biopsy showed large B-cell lymphoma cells in the microvessels within the myocardium. To the best of our knowledge, this is the first report of imaging findings of cardiac involvement in IVLBCL.

Effectiveness of hyperbaric oxygen therapy for virus-associated hemorrhagic cystitis after allogeneic hematopoietic stem cell transplantation.

Although some studies have suggested the effectiveness of hyperbaric oxygen (HBO) therapy for hemorrhagic cystitis (HC) after allogeneic hematopoietic stem cell transplantation (HSCT), the role of HBO has not been established. We compared the treatment outcomes of 8 patients with viral HC (adenovirus [ADV], n = 2; BK virus [BKV], n = 6) treated with HBO (HBO[+]) and 8 patients (ADV, n = 2; BKV, n = 6) treated with conventional therapy (HBO[-]), such as urinary catheterization and intravenous cidofovir. HBO therapy was performed at 2.1 atmospheres for 90 min/day until clinical improvement was achieved. The median number of HBO treatments was 10 (range 8-12). The median duration of HBO treatment was 19.5 days (range 10-23 days). All 8 HBO(+) patients achieved complete remission (CR) at a median of 14.5 days (range 5-25 days). Of the 8 HBO(-) patients, 5 (62.5%) obtained CR and 3 remained symptomatic for 2-6 months. The cumulative incidence of transplant-related mortality at day 100 after allogeneic HSCT was significantly higher in the HBO(-) patients than in the HBO(+) patients (14.2 vs. 0%, P < 0.05). No severe HBO-related adverse effects were observed. In conclusion, HBO is a feasible option for treating viral HC after allogeneic HSCT.

Detection of Antibodies Against Human Leukocyte Antigen Class II in the Sera of Patients Receiving Intravenous Immunoglobulin.

IVIG is occasionally used for preventing and treating severe infections of patients who are to undergo transplantation. Administration of IVIG, which includes high-titer antibodies (Abs) against HLA class I and II, might have a substantial influence on the HLA Ab test results of these patients. However, this issue has remained unreported. METHODS: Anti-HLA Ab titers were determined in 4 types of IVIG preparations, fresh frozen plasma, and the sera of 11 patients with hematological diseases before and after IVIG administration. RESULTS: Although anti-HLA Abs were not detected in any of the fresh frozen plasma products, various anti-HLA class I and II Abs were detected in all 4 IVIG preparations. Six out of 11 patients who had received IVIG showed a low titer of anti-HLA class II Abs, which were not detected before IVIG administration. Conversely, no anti-HLA class I Abs were detected in any of the 11 patients. Furthermore, all 4 (100%) patients who were positive for anti-HLA class II Abs initially and were assessable became negative for anti-HLA Abs after the discontinuation of IVIG treatment (median, d 79; range, d 22-192). CONCLUSIONS: IVIG preparations consist of high-titer anti-HLA class I and II Abs, but the latter can be transiently detected in the sera of patients who had received IVIG. When these patients are screened for the presence of donor-specific Abs, some may be incorrectly deemed positive for HLA class II Abs. Thus, caution is necessary when only donor-specific Abs specific to class II HLAs are detected in patients.

Resistance of KIR Ligand-Missing Leukocytes to NK Cells In Vivo in Patients with Acquired Aplastic Anemia.

The loss of killer cell Ig-like receptor ligands (KIR-Ls) due to the copy number-neutral loss of heterozygosity of chromosome 6p (6pLOH) in leukocytes of patients with acquired aplastic anemia (AA) may alter the susceptibility of the affected leukocytes to NK cell killing in vivo. We studied 408 AA patients, including 261 who were heterozygous for KIR-Ls, namely C1/C2 or Bw6/Bw4, for the presence of KIR-L-missing [KIR-L(-)] leukocytes. KIR-L(-) leukocytes were found in 14 (5.4%, C1 [n = 4], C2 [n = 3], and Bw4 [n = 7]) of the 261 patients, in whom corresponding KIR(+) licensed NK cells were detected. The incidence of 6pLOH in the 261 patients (18.0%) was comparable to that in 147 patients (13.6%) who were homozygous for KIR-L genes. The percentages of HLA-lacking granulocytes (0.8-50.3%, median 15.2%) in the total granulocytes of the patients with KIR-L(-) cells were significantly lower than those (1.2-99.4%, median 55.4%) in patients without KIR-L(-) cells. KIR2DS1 and KIR3DS1 were only possessed by three of the 14 patients, two of whom had C2/C2 leukocytes after losing C1 alleles. The expression of the KIR3DS1 ligand HLA-F was selectively lost on KIR-L(-) primitive hematopoietic stem cells derived from 6pLOH(+) induced pluripotent stem cells in one of the KIR3DS1(+) patients. These findings suggest that human NK cells are able to suppress the expansion of KIR-L(-) leukocytes but are unable to eliminate them partly due to the lack of activating KIRs on NK cells and the low HLA-F expression level on hematopoietic stem cells in AA patients.

Sustained clonal hematopoiesis by HLA-lacking hematopoietic stem cells without driver mutations in aplastic anemia.

Clonal hematopoiesis by hematopoietic stem progenitor cells (HSPCs) that lack an HLA class I allele (HLA- HSPCs) is common in patients with acquired aplastic anemia (AA); however, it remains unknown whether the cytotoxic T lymphocyte (CTL) attack that allows for survival of HLA- HSPCs is directed at nonmutated HSPCs or HSPCs with somatic mutations or how escaped HLA- HSPC clones support sustained hematopoiesis. We investigated the presence of somatic mutations in HLA- granulocytes obtained from 15 AA patients in long-term remission (median, 13 years; range, 2-30 years). Targeted sequencing of HLA- granulocytes revealed somatic mutations (DNMT3A, n = 2; TET2, ZRSR2, and CBL, n = 1) in 3 elderly patients between 79 and 92 years of age, but not in 12 other patients aged 27 to 74 years (median, 51.5 years). The chronological and clonogenic analyses of the 3 cases revealed that ZRSR2 mutation in 1 case, which occurred in an HLA- HSPC with a DNMT3A mutation, was the only mutation associated with expansion of the HSPC clone. Whole-exome sequencing of the sorted HLA- granulocytes confirmed the absence of any driver mutations in 5 patients who had a particularly large loss of heterozygosity in chromosome 6p (6pLOH) clone size. Flow-fluorescence in situ hybridization analyses of sorted HLA+ and HLA- granulocytes showed no telomere attrition in HLA- granulocytes. The findings suggest that HLA- HSPC clones that escape CTL attack are essentially free from somatic mutations related to myeloid malignancies and are able to support long-term clonal hematopoiesis without developing driver mutations in AA patients unless HLA loss occurs in HSPCs with somatic mutations.

Hematopoiesis by iPSC-derived hematopoietic stem cells of aplastic anemia that escape cytotoxic T-cell attack.

Hematopoietic stem cells (HSCs) that lack HLA-class I alleles as a result of copy-number neutral loss of heterozygosity of the short arm of chromosome 6 (6pLOH) or HLA allelic mutations often constitute hematopoiesis in patients with acquired aplastic anemia (AA), but the precise mechanisms underlying clonal hematopoiesis induced by these HLA-lacking (HLA-) HSCs remain unknown. To address this issue, we generated induced pluripotent stem cells (iPSCs) from an AA patient who possessed HLA-B4002-lacking (B4002-) leukocytes. Three different iPSC clones (wild-type [WT], 6pLOH+, and B*40:02-mutant) were established from the patient's monocytes. Three-week cultures of the iPSCs in the presence of various growth factors produced hematopoietic cells that make up 50% to 70% of the CD34+ cells of each phenotype. When 106 iPSC-derived CD34+ (iCD34+) cells with the 3 different genotypes were injected into the femoral bone of C57BL/6.Rag2 mice, 2.1% to 7.3% human multilineage CD45+ cells of each HLA phenotype were detected in the bone marrow, spleen, and peripheral blood of the mice at 9 to 12 weeks after the injection, with no significant difference in the human:mouse chimerism ratio among the 3 groups. Stimulation of the patient's CD8+ T cells with the WT iCD34+ cells generated a cytotoxic T lymphocyte (CTL) line capable of killing WT iCD34+ cells but not B4002- iCD34+ cells. These data suggest that B4002- iCD34+ cells show a repopulating ability similar to that of WT iCD34+ cells when autologous T cells are absent and CTL precursors capable of selectively killing WT HSCs are present in the patient's peripheral blood.