Myelodysplasia after clonal hematopoiesis with APOBEC3-mediated CYBB inactivation in retroviral gene therapy for X-CGD

Stem cell gene therapy using the MFGS-gp91phox retroviral vector was performed on a 27-year-old patient with X-linked chronic granulomatous disease (X-CGD) in 2014. The patient's refractory infections were resolved, whereas the oxidase-positive neutrophils disappeared within 6 months. Thirty-two months after gene therapy, the patient developed myelodysplastic syndrome (MDS), and vector integration into the MECOM locus was identified in blast cells. The vector integration into MECOM was detectable in most myeloid cells at 12 months after gene therapy. However, the patient exhibited normal hematopoiesis until the onset of MDS, suggesting that MECOM transactivation contributed to clonal hematopoiesis, and the blast transformation likely arose after the acquisition of additional genetic lesions. In whole-genome sequencing, the biallelic loss of the WT1 tumor suppressor gene, which occurred immediately before tumorigenesis, was identified as a potential candidate genetic alteration. The provirus CYBB cDNA in the blasts contained 108 G-to-A mutations exclusively in the coding strand, suggesting the occurrence of APOBEC3-mediated hypermutations during the transduction of CD34-positive cells. A hypermutation-mediated loss of oxidase activity may have facilitated the survival and proliferation of the clone with MECOM transactivation. Our data provide valuable insights into the complex mechanisms underlying the development of leukemia in X-CGD gene therapy.

Recent topics and advanced therapies in chronic granulomatous disease

Chronic granulomatous disease (CGD) is a primary immunodeficiency characterized by the inability of phagocytes to produce reactive oxygen species (ROS) owing to a defect in any of the five components (CYBB/gp91phox, CYBA/p22phox, NCF1/p47phox, NCF2/p67phox, and NCF4/p40phox) and a concomitant regulatory component of Rac1/2 and CYBC1/Eros of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase complex. Patients with CGD are at an increased risk of life-threatening infections caused by catalase-positive bacteria and fungi and of inflammatory complications such as CGD colitis. Antimicrobial and azole antifungal prophylaxes have considerably reduced the incidence and severity of bacterial and improved fungal infections and overall survival. CGD studies have revealed the precise epidemiology and role of NADPH oxidase in innate immunity which has led to a new understanding of the importance of phagocyte oxygen metabolism in various host-defense systems and the fields leading to cell death processes. Moreover, ROS plays central roles in the determination of cell fate as secondary messengers and by modifying of various signaling molecules. According to this increasing knowledge about the effects of ROS on the inflammasomal system, immunomodulatory treatments, such as IFN-γ and anti-IL-1 antibodies, have been established. This review covers the current topics in CGD and the relationship between ROS and ROS-mediated pathophysiological phenomena. In addition to the shirt summary of hematopoietic stem cell transplantation and gene therapy, we introduce a novel ROS-producing enzyme replacement therapy using PEG-fDAO to compensate for NADPH oxidase deficiency.

Recombinant human thrombomodulin for pneumonia-induced severe ARDS complicated by DIC in children: a preliminary study

Purpose

Recombinant human soluble thrombomodulin (rTM) has been used to treat disseminated intravascular coagulation (DIC). Recent studies have shown the efficacy of rTM through its anti-inflammatory effects for treatment of adults with acute respiratory distress syndrome (ARDS). However, the safety and efficacy of rTM in children with severe ARDS complicated by DIC have not been reported. In this preliminary study, we reported the feasibility of using rTM for the treatment of pneumonia-induced severe ARDS complicated by DIC in children.

Methods

Six children (age: median 10 months old) with pneumonia-induced severe ARDS complicated by DIC were enrolled in this preliminary study. rTM (380 U/kg) was administered for a maximum of 6 days, in addition to conventional therapies after diagnosis of severe ARDS complicated by DIC. After administration of rTM, we measured changes in the plasma TM concentration and evaluated the clinical course, status of DIC and ARDS, and other laboratory findings, including levels of cytokines, chemokines, and biomarkers.

Results

In all six children, the plasma concentration of TM increased and DIC scores decreased after administration of rTM. Four of the six children recovered from the severe ARDS complicated by DIC after treatment, and were discharged from the hospital with no complications. In survived children, levels of soluble receptors for advanced glycation end products, interleukin-6, interleukin-8 and monocyte chemotactic protein-1 decreased after administration of rTM compared to those before rTM.

Conclusions

The rTM administration is feasible as an adjunctive therapeutic strategy for children over 2 months with pneumonia-induced severe ARDS complicated by DIC.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00540-021-02971-3.

Hematopoietic Cell Transplantation for Chronic Granulomatous Disease in Japan

Hematopoietic cell transplantation (HCT) is established as a curative treatment for severe chronic granulomatous disease (CGD). However, outcomes of HCT for CGD in Japan had not been precisely reported. We evaluated the outcome of HCT for CGD in Japan by means of a nationwide survey. A total of 91 patients (86 males and 5 females) with CGD who received HCT between 1992 and 2013 was investigated. Their median age at HCT was 11 years (0–39). Sixty-four patients had X-linked CGD caused by CYBB gene mutations, 13 had autosomal recessive CGD (7 CYBA and 6 NCF2), and 14 were genetically undetermined. Seventy patients are still alive at a median follow-up of 38.9 (3.7–230) months. Three-year OS and EFS was 73.7 and 67.6%, respectively. Twenty-one patients died mainly from transplant-related mortality. The cumulative incidence of grade II to IV acute GVHD and extensive chronic GVHD was 27.2 and 17.9%, respectively. Risk factors for EFS after HCT for CGD were age >30 years (P < 0.01), non-CYBB gene mutations (P < 0.01) and CBT (P < 0.01). Regarding the reduced intensity conditioning (RIC) regimen, risk factors for EFS included anti-thymocyte globulin (P = 0.048) and not using low-dose irradiation therapy (P < 0.01), in addition to the preceding risk factors. We report outcomes of HCT for CGD in Japan. Future studies are needed to improve such outcomes, especially for patients harboring non-CYBB gene mutations and suffering from adult CGD. A RIC regimen including low-dose irradiation may be a good option to explore further.

TAE226, a dual inhibitor of focal adhesion kinase and insulin-like growth factor-I receptor, is effective for Ewing sarcoma

The outcomes for relapsed and metastatic Ewing sarcoma (EWS) is extremely poor. Therefore, it is important to identify the tumor‐specific targets in these intractable diseases. High focal adhesion kinase (FAK) transcript expression levels in EWS cell lines are known. TAE226 is a dual inhibitor of FAK and insulin‐like growth factor‐I receptor (IGF‐IR), while PF‐562,271 is a dual inhibitor of FAK and proline‐rich tyrosine kinase 2. We compared the cytotoxicity of TAE226 and PF‐562,271 toward three EWS cell lines. TAE226 strongly inhibited proliferation of three cell lines when compared with PF‐562,271. Furthermore, we investigated the efficacy of TAE226 as well as its mechanism of action against EWS. A stable EWS cell line with FAK and IGF‐IR knocked down was established, and microarray analysis revealed dysregulated expression in various pathways. TAE226 treatment of EWS cell lines induced cell cycle arrest, apoptosis, AKT dephosphorylation, and inhibition of invasion. We demonstrated that TAE226 drastically inhibits the local growth of primary tumors and metastasis in EWS using mouse models. Furthermore, the combination of TAE226 and conventional chemotherapy proved to exert synergistic effects. TAE226 may be a candidate single agent or combined therapy drug to be developed for patients who have relapse and metastatic EWS tumors in future.

Robust and highly efficient hiPSC generation from patient non-mobilized peripheral blood-derived CD34+ cells using the auto-erasable Sendai virus vector

BACKGROUND

Disease modeling with patient-derived induced pluripotent stem cells (iPSCs) is a powerful tool for elucidating the mechanisms underlying disease pathogenesis and developing safe and effective treatments. Patient peripheral blood (PB) cells are used for iPSC generation in many cases since they can be collected with minimum invasiveness. To derive iPSCs that lack immunoreceptor gene rearrangements, hematopoietic stem and progenitor cells (HSPCs) are often targeted as the reprogramming source. However, the current protocols generally require HSPC mobilization and/or ex vivo expansion owing to their sparsity at the steady state and low reprogramming efficiencies, making the overall procedure costly, laborious, and time-consuming.

METHODS

We have established a highly efficient method for generating iPSCs from non-mobilized PB-derived CD34+ HSPCs. The source PB mononuclear cells were obtained from 1 healthy donor and 15 patients and were kept frozen until the scheduled iPSC generation. CD34+ HSPC enrichment was done using immunomagnetic beads, with no ex vivo expansion culture. To reprogram the CD34+-rich cells to pluripotency, the Sendai virus vector SeVdp-302L was used to transfer four transcription factors: KLF4, OCT4, SOX2, and c-MYC. In this iPSC generation series, the reprogramming efficiencies, success rates of iPSC line establishment, and progression time were recorded. After generating the iPSC frozen stocks, the cell recovery and their residual transgenes, karyotypes, T cell receptor gene rearrangement, pluripotency markers, and differentiation capability were examined.

RESULTS

We succeeded in establishing 223 iPSC lines with high reprogramming efficiencies from 15 patients with 8 different disease types. Our method allowed the rapid appearance of primary colonies (~ 8 days), all of which were expandable under feeder-free conditions, enabling robust establishment steps with less workload. After thawing, the established iPSC lines were verified to be pluripotency marker-positive and of non-T cell origin. A majority of the iPSC lines were confirmed to be transgene-free, with normal karyotypes. Their trilineage differentiation capability was also verified in a defined in vitro assay.

CONCLUSION

This robust and highly efficient method enables the rapid and cost-effective establishment of transgene-free iPSC lines from a small volume of PB, thus facilitating the biobanking of patient-derived iPSCs and their use for the modeling of various diseases.

Influence of food texture on energy metabolism and adiposity in male rats

NEW FINDINGS

What is the central question of this manuscript? What is the effect of food texture on fat accumulation, lipogenesis and proinflammatory factors in the adipose tissue and on energy balance in male rats? What is the main finding and its importance? Calorie intake and fat accumulation in rats fed soft pellets ad libitum increased, but their body weight did not. The data suggest that, even when BMI is normal, frequent consumption of soft food may contribute to the development of lifestyle-related diseases.

ABSTRACT

Dietary factors such as food texture are known to affect feeding behaviour and energy metabolism. We recently found that rats fed soft pellets (SPs) on a 3 h restricted feeding schedule showed glucose intolerance, insulin resistance with disruption of insulin signalling, and hyperplasia of pancreatic β-cells, even though there were no differences in energy intake and body weight between rats fed control pellets (CPs) and rats fed SPs. We investigated the effect of food texture on fat accumulation, lipogenesis and proinflammatory factors in the mesenteric fat, as well as on energy balance in male rats fed CPs or SPs. We used 7-week-old Wistar rats that were randomly divided into two groups, ad libitum fed either CPs or SPs for 27 weeks. Body weight and calorie intake were monitored once a week throughout the experiment. The calorie intake, lipogenesis and fat accumulation of the rats fed SPs increased, whereas their body weight did not. Additionally, SP rats used their fat mainly as a source of energy and increased their energy expenditure. Our data suggest that the habit of frequently eating soft food causes visceral fat accumulation without an increase in body weight. Further investigations using soft-textured foods could lead to the development of appropriate interventions for non-overweight patients with lifestyle-related diseases.

Pathogen screening and prognostic factors in children with severe ARDS of pulmonary origin

BACKGROUND

Acute respiratory distress syndrome (ARDS) is one of the most lethal diseases encountered in the pediatric intensive care unit (PICU). The etiological pathogens and prognostic factors of severe ARDS of pulmonary origin in children with respiratory virus infections were prospectively investigated.

METHODS

Enrolled children fulfilled the following criteria: (1) PICU admission; (2) age of 1 month to 16 years; (3) diagnosis of infectious pneumonia and respiratory virus infection; and (4) development of severe ARDS within 72 h after PICU admission. Pathogens were detected in the blood and tracheal lavage fluid using molecular techniques and a conventional culture system. The serum levels of inflammatory mediators on the day of PICU admission were examined.

RESULTS

Fifty-seven patients (32 boys; median age, 9 months) were enrolled. Multiple virus infections, co-infection with bacteria/fungus, and bacteremia/fungemia were observed in 60%, 49%, and 32% of children, respectively. Adenovirus-B, measles virus, and cytomegalovirus were detected predominantly in tracheal lavage fluid. There were no statistically significant differences between non-survivors and survivors regarding the types of pathogen, incidence of multiple virus infection, gender, age, clinical features, and treatment. The serum levels of interferon (IFN)-γ and the IFN-γ/interleukin (IL)-10 ratio were higher in non-survivors.

CONCLUSIONS

IFN-γ upregulation as detected on the day of PICU admission was found to be one of the possible prognostic factors affecting a fatal outcome. These results suggest that modulation of inflammatory responses is critical for the clinical management of children with ARDS.

Clinical and histological findings of autosomal dominant renal-limited disease with LMX1B mutation

AIM

Mutations of LMX1B cause nail-patella syndrome, a rare autosomal dominant disorder. Recently, LMX1B R246Q heterozygous mutations were recognised in nephropathy without extrarenal manifestation. The aim of this study was to clarify characteristics of nephropathy caused by R246Q mutation.

METHODS

Whole exome sequencing was performed on a large family with nonsyndromic autosomal dominant nephropathy without extrarenal manifestation. Clinical and histological findings of patients with LMX1B mutation were investigated.

RESULTS

LMX1B R246Q heterozygous mutation was identified in five patients over three generations. Proteinuria or haematoproteinuria was recognized by urinary screening from all patients in childhood. Proteinuria gradually increased to nephrotic levels and renal function decreased in adolescence. Two patients progressed to end-stage renal disease in adulthood. Renal histology demonstrated minimal change in childhood and focal segmental glomerulosclerosis in adulthood. Using electron microscopy, focal collagen deposition could be detected in glomeruli even when a "moth-eaten appearance" was not apparent in the glomerular basement membrane. In addition, podocin expression in glomerular podocytes was significantly decreased, even in the early stages of disease progression.

CONCLUSION

Comprehensive genetic analyses and collagen or tannic acid staining may be useful for diagnosis of LMX1B-associated nephropathy. While renal prognosis of R246Q may be worse than that of typical NPS nephropathy, signs of podocytopathy can be detected during the infantile period; thus, childhood urinary screening may facilitate early detection.

Relapsed childhood acute myeloid leukemia patient with inversion of chromosome 16 harboring a low FLT3 internal tandem duplication allelic burden and KIT mutations

Inversion of chromosome 16 [inv(16)] has a good prognosis in acute myeloid leukemia (AML), but additional genetic aberrations influence the outcome. We herein describe the case of a 15-year-old Japanese boy with inv(16) harboring a low-allelic burden internal tandem duplication of FLT3 (FLT3-ITD) and KIT mutations. Conventional chemotherapy eradicated a clone with a low-allelic burden FLT3-ITD mutation, although another clone with a KIT mutation occurred 17 months later. Further investigation is necessary to identify AML with inv(16) conferring poor prognosis, to facilitate appropriate treatment with additional drugs, such as dasatinib or gemtuzumab ozogamicin.

Autoimmunity Including Intestinal Behçet Disease Bearing the KRAS Mutation in Lymphocytes: A Case Report

We experienced the case of a 3-year-old male with a very rare combination of autoimmunity, including immune thrombocytopenia, recurrent Henoch-Schönlein purpura and intestinal Behçet disease. Exome sequencing of the patient's peripheral blood mononuclear cells identified a KRAS G13C mutation. Interestingly, the KRAS G13C mutation was observed in T and B lymphocytes, as well as natural killer cells, but not granulocytes. Our case was completely phenotypically different from RASopathies and did not meet the criteria for Ras-associated lymphoproliferative disease or juvenile myelomonocytic leukemia. This is the first reported case in which the KRAS mutation existed only in the lymphoid lineage. Based on the findings of our case and the current literature, it is clear that the RAS mutation in lymphoid cells is tightly linked with various autoimmune symptoms. The presence of the RAS mutation in lymphocytes should be reconsidered as a pathogenesis in cases of autoimmunity.

Role of the neural pathway from hindbrain to hypothalamus in the regulation of energy homeostasis in rats

Recent evidence suggests that neural pathways from the hindbrain to the hypothalamus are important for informing the hypothalamus of the body's condition with regard to energy metabolism. Here we examined energy metabolism in rats with transections of the midbrain that severed the neural pathway from the hindbrain to the hypothalamus, and then investigated the levels of various molecules associated with control of energy metabolism in these rats. Food intake and body weight were higher in the midbrain-transected rats than in sham-operated rats. In addition, the midbrain-transected rats showed insulin resistance and hyperleptinemia. Furthermore, the hypothalamic mRNA levels of anorectic proopiomelanocortin and cocaine- and amphetamine-related transcript were significantly lower in midbrain-transected rats than in sham-operated rats. Our findings elucidate the mechanisms of food intake and energy balance from the perspective of multifactorial regulatory systems that underlie functions such as neurohormonal integration.

Leopard Skin-Like Colonic Mucosa: A Novel Endoscopic Finding of Chronic Granulomatous Disease-Associated Colitis

BACKGROUND

Chronic granulomatous disease (CGD) is a rare inherited disorder in which phagocytes are unable to eradicate pathogens because of a deficit of nicotinamide adenine dinucleotide phosphate oxidase. Among CGD patients, ∼ 30% to 50% develop severe gastrointestinal tract symptoms. Although characteristic histologic findings of CGD-associated colitis have been reported, information on endoscopic features remained vague.

METHODS

A total of 8 male patients with CGD (ages 2-23 years) from 2 Japanese institutions underwent colonoscopy for the evaluation of their fever, diarrhea, bloody stool, and abdominal pain. The endoscopic and histologic findings were retrospectively reviewed.

RESULTS

The endoscopic findings of CGD-associated colitis appeared varied. Notably, brownish dots over a yellowish edematous mucosa were observed in 3 of the 8 patients. Prominent pigment-laden macrophages were noted histologically on the mucosa.

CONCLUSIONS

Although nonspecific endoscopic findings of CGD-associated colitis have been reported before, our observation of brownish dots spread across a yellowish edematous mucosa, termed "leopard sign," could be a unique feature of this condition.

Sporadic paraganglioma caused by de novo SDHB mutations in a 6-year-old girl

Germline mutations in the succinate dehydrogenase complex subunit B (SDHB) gene (SDHB) cause susceptibility to paragangliomas and pheochromocytomas; however, it is exceedingly rare in childhood and especially in sporadic cases. We report the first Japanese pediatric case of paraganglioma with a de novo mutation in the SDHB gene. A 6-year-old girl with convulsions and hypertension was found to have a paravertebral abdominal tumor. Urinary and blood examinations revealed markedly elevated levels of norepinephrine. Following treatment for hypertension, the tumor was removed completely and histological findings were consistent with paraganglioma. Immunohistochemistry studies demonstrated the absence of SDHB protein expression, indicating an underlying SDH mutation with high probability. Germline mutation analysis of the SDHB gene revealed a heterozygous splice site mutation in intron 4 (C.423 + 1G > A). Subsequently, a second somatic genetic change was confirmed by multiplex ligation-dependent probe amplification (MLPA) analysis, showing that deletion of the wild-type allele resulted in loss of function of SDHB. No germline mutations in SDHB were detected in her parents.

CONCLUSION

Genetic testing should be considered for pediatric patients with paragangliomas, even in the absence of familial history, as closer lifelong screening to detect the development of malignancy will be required for patients with SDHB mutations.

WHAT IS KNOWN

Most sporadic cases of paraganglioma with SDHB mutations occur between adolescence and adulthood. Screening methods for carriers of SDHB mutations assessing recurrence and detecting developing metastases are yet to be standardized.

WHAT IS NEW

The current case of an extra-adrenal paraganglioma with a de novo SDHB mutation had an onset at 6 years. We suggest much closer periodical observation for these high-risk children.

Infantile Cases of Sitosterolaemia with Novel Mutations in the ABCG5 Gene: Extreme Hypercholesterolaemia is Exacerbated by Breastfeeding

Few data exists regarding the clinical impact of breastfeeding in infantile sitosterolaemic cases. We report four Japanese infantile cases of sitosterolaemia, an extremely rare inherited disease characterised by increased serum levels of plant sitosterol, presenting with severe hypercholesterolaemia and systemic xanthomas exacerbated by breastfeeding. In these four cases, genetic analyses were performed for low-density lipoprotein (LDL) receptor, proprotein convertase subtilisin/kexin type 9 (PCSK9), LDL receptor adaptor protein 1 and ATP-binding cassette (ABC) subfamily G member 5 and 8 (ABCG5 and ABCG8) genes. We assessed their clinical manifestations, including responsiveness to a variety of treatments, especially to weaning from breastfeeding and use of ezetimibe. Two pairs of mutations in the ABCG5 gene in each case, including two novel mutations (c.130C>T or p.Ser44Ala and c.1813_1817delCTTTT or p.Pro558GlufsX14) and two known mutations (c.1306G>A or p.Arg389His and c.1336C>T or p.Arg446X), were identified. Significant reductions in cholesterol levels were obtained by means of weaning from breastfeeding alone. Substantial reductions in sitosterol levels, without any apparent side effects, were observed with ezetimibe. In conclusion, we have identified infantile Japanese sitosterolaemic subjects with extreme hypercholesterolaemia exacerbated by breastfeeding. Their unique response to weaning from breastfeeding, as well as to use of ezetimibe, could provide insights into the metabolic basis of sterols in humans.

Proposed strategy for the use of high-dose chemotherapy with stem cell rescue and intrathecal topotecan without whole-brain irradiation for infantile classic medulloblastoma

We describe a 6-month-old infant with classic medulloblastoma. Gross total resection of the left cerebellar tumor was performed; however, relapse occurred during the administration of intrathecal and intravenous methotrexate-based chemotherapy. After undergoing resection, high-dose chemotherapy was administered consisting of topotecan, melphalan, and cyclophosphamide with autologous peripheral stem cell rescue followed by local irradiation and intrathecal topotecan, which resulted in a complete response for more than two years. The administration of high-dose chemotherapy followed by intrathecal topotecan as maintenance therapy is an effective strategy, without losses in the cognitive function, for avoiding the use of whole-brain irradiation for infantile classic medulloblastoma.

Medium-chain triglyceride supplementation under a low-carbohydrate formula is a promising therapy for adult-onset type II citrullinemia

Background

Citrin, encoded by SLC25A13, is a component of the malate-aspartate shuttle, which is the main NADH-transporting system in the liver. Citrin deficiency causes neonatal intrahepatic cholestasis (NICCD), which usually resolves within the first year of life. However, small numbers of adults with citrin deficiency develop hyperammonemic encephalopathy, adult-onset type II citrullinemia (CTLN2), which leads to death due to cerebral edema. Liver transplantation is the only definitive therapy for patients with CTLN2. We previously reported that a lactose (galactose)-restricted and medium-chain triglyceride (MCT)-supplemented formula is notably effective for patients with NICCD. Citrin deficiency may impair the glycolysis in hepatocytes because of an increase in the cytosolic NADH/NAD⁺ ratio, leading to an energy shortage. MCT administration can provide energy to hepatocytes and was expected to have a good effect on CTLN2.

Methods

An MCT supplementation therapy under a low-carbohydrate formula was administered to five patients with CTLN2. Four of the patients had episodes of hyperammonemic encephalopathy, and one patient had postprandial hyperammonemia with no symptoms.

Results

One of the patients displaying hyperammonemic encephalopathy completely recovered with all normal laboratory findings. Others notably improved in terms of clinical and or laboratory findings with no hyperammonemic symptoms; however, the patients displayed persistent mild citrullinemia and occasionally had postprandial mild hyperammonemia most likely due to an irreversible change in the liver.

Conclusions

An MCT supplement can provide energy to hepatocytes and promote hepatic lipogenesis, leading to a reduction in the cytosolic NADH/NAD⁺ ratio. MCT supplementation under a low-carbohydrate formula could be a promising therapy for CTLN2 and should also be used to prevent CTLN2 to avoid irreversible liver damage.

[Refractory acute myeloid leukemia developed malignancy-associated hemophagocytic lymphohistiocytosis during treatment of invasive fungal infection]

We here report a 2-year-old female with relapsed acute myeloid leukemia (AML) with MLL gene rearrangement in the bone marrow and central nervous system. The 3'-RACE (Rapid Amplification of cDNA Ends) method identified the MLLT10 gene as a fusion partner of the MLL gene. The patient was complicated with hemophagocytic lymphohistiocytosis (HLH) and invasive aspergillosis (IPA) after re-induction treatment with FLAG-IDA following etoposide, cytarabine, and mitoxantrone. Although treatment with systemic anti-fungal drugs was effective for IPA, HLH did not improve. We considered tumor-associated HLH to be initiated from leukemic stem cells (LSCs) in the bone marrow niche because reverse transcription-polymerase chain reaction (RT-PCR) analysis of a bone marrow biopsy sample was positive for MLL-MLLT10. Gemtuzumab ozogamicin and sorafenib had no major effect on acquiring complete remission, and the patient died of progressive AML with an exacerbation of HLH and aspergillosis. LSCs are known to be resistant to conventional chemotherapy due to their quiescence in the cell cycle. Novel therapeutic concepts are important to eradicate LSCs in order to cure AML patients.

Cytomegalovirus retinitis as an adverse immunological effect of pulses of vincristine and dexamethasone in maintenance therapy for childhood acute lymphoblastic leukemia

We describe a 5-year-old female with acute lymphoblastic leukemia (ALL) who suffered from cytomegalovirus (CMV) retinitis during maintenance therapy consisting of 6-mercaptopurine (6-MP) and methotrexate (MTX) with pulses of vincristine (VCR) and dexamethasone (DEX). Administration of anticytomegaloviral drugs led to a complete regression of active retinitis. Her low CD4 positive T cells and serum immunoglobulin G (IgG) recovered when maintenance therapy was resumed without VCR and DEX. The patient has been in complete remission (CR) for more than 5 months after completion of maintenance therapy without recurrence of CMV retinitis.

A Dual Reporter Splicing Assay Using HaloTag-containing Proteins

To evaluate the effects of genetic variations on mRNA splicing, we developed a minigene-based splicing assay using reporter genes encoding luciferase and the multifunctional HaloTag protein. In addition to conventional RT-PCR analysis, splicing events can be monitored in this system using two parameters: luciferase activity and signals derived from HaloTag-containing proteins bound to a fluorescent ligand following SDS-PAGE. The luciferase activity reflects the accumulated amounts of successfully spliced HaloTag-luciferase fusion products, whereas the amounts and sizes of HaloTag-containing proteins provide quantitative insights into precursor, correctly spliced, and aberrantly spliced mRNA species. Preliminary experiments confirmed that the dual reporter minigene assay can provide estimates of overall splicing efficiency based on the levels of protein products. We then used the minigene assay to analyze a case of chronic granulomatous disease that was caused by a G>C mutation at position +5 in the 5'-splice donor site of intron 5 of the CYBB gene. We found that the G>C mutation affected CYBB mRNA splicing by changing a delicate balance of splicing efficiencies of introns 4, 5, and 6.

PEGylated D-amino acid oxidase restores bactericidal activity of neutrophils in chronic granulomatous disease via hypochlorite

Chronic granulomatous disease (CGD) causes impaired hydrogen peroxide (H(2)O(2)) generation. Consequently, neutrophils in patients with CGD fail to kill infecting pathogens. We expected that supplementation with H(2)O(2) would effectively restore the bactericidal function of neutrophils in CGD. Here, we used polyethylene glycol-conjugated D-amino acid oxidase (PEG-DAO) as an H(2)O(2) source. The enzyme DAO generates H(2)O(2) by using D-amino acid and oxygen as substrates. PEG-DAO plus D-amino acid indeed exerted bacteriostatic activity against Staphylococcus aureus via H(2)O(2) in vitro. Furthermore, use of PEG-DAO plus D-amino acids, which increased the amount of intracellular H(2)O(2), restored bactericidal activity of neutrophils treated with diphenylene iodonium, in which nicotinamide adenine dinucleotide phosphate (NADPH) oxidase was defective. This restoration of bactericidal activity was mediated by myeloperoxidase, with concomitant production of H(2)O(2) by PEG-DAO plus D-Ala. We also confirmed that PEG-DAO treatment restored bactericidal activity of congenitally defective neutrophils from patients with CGD. These results indicate that PEG-DAO can supply additional H(2)O(2) for defective NADPH oxidase of neutrophils from patients with CGD, and thus neutrophils regain bactericidal activity.

Copy number variations due to large genomic deletion in X-linked chronic granulomatous disease

Mutations in genes for any of the six subunits of NADPH oxidase cause chronic granulomatous disease (CGD), but almost 2/3 of CGD cases are caused by mutations in the X-linked CYBB gene, also known as NAD (P) H oxidase 2. Approximately 260 patients with CGD have been reported in Japan, of whom 92 were shown to have mutations of the CYBB gene and 16 to have chromosomal deletions. However, there has been very little detailed analysis of the range of the deletion or close understanding of the disease based on this. We therefore analyzed genomic rearrangements in X-linked CGD using array comparative genomic hybridization analysis, revealing the extent and the types of the deletion genes. The subjects were five Japanese X-linked CGD patients estimated to have large base deletions of 1 kb or more in the CYBB gene (four male patients, one female patient) and the mothers of four of those patients. The five Japanese patients were found to range from a patient exhibiting deletions only of the CYBB gene to a female patient exhibiting an extensive DNA deletion and the DMD and CGD phenotype manifested. Of the other three patients, two exhibited CYBB, XK, and DYNLT3 gene deletions. The remaining patient exhibited both a deletion encompassing DNA subsequent to the CYBB region following intron 2 and the DYNLT3 gene and a complex copy number variation involving the insertion of an inverted duplication of a region from the centromere side of DYNLT3 into the deleted region.

Successful treatment with infliximab for inflammatory colitis in a patient with X-linked anhidrotic ectodermal dysplasia with immunodeficiency

X-linked anhidrotic ectodermal dysplasia with immunodeficiency (X-EDA-ID) is caused by hypomorphic mutations in the gene encoding nuclear factor-κB essential modulator protein (NEMO). Patients are susceptibile to diverse pathogens due to insufficient cytokine and frequently show severe chronic colitis. An 11-year-old boy with X-EDA-ID was hospitalized with autoimmune symptoms and severe chronic colitis which had been refractory to immunosuppressive drugs. Since tumor necrosis factor (TNF) α is responsible for the pathogenesis of NEMO colitis according to intestinal NEMO and additional TNFR1 knockout mice studies, and high levels of TNFα-producing mononuclear cells were detected in the patient due to the unexpected gene reversion mosaicism of NEMO, an anti-TNFα monoclonal antibody was administered to ameliorate his abdominal symptoms. Repeated administrations improved his colonoscopic findings as well as his dry skin along with a reduction of TNFα-expressing T cells. These findings suggest TNF blockade therapy is of value for refractory NEMO colitis with gene reversion.

Comparison of the epidemiology of anti-neutrophil cytoplasmic antibody-associated vasculitis between Japan and the U.K

OBJECTIVES

The epidemiological manifestations of ANCA-associated vasculitis (AAV) differ geographically. However, there have been no prospective studies comparing the incidence of AAV between Japan and Europe over the same time period using the same case definitions.

METHODS

The incidence of AAV was determined by a population-based method in Miyazaki prefecture, Japan, and Norfolk, U.K., between 2005 and 2009. Patients with AAV were defined and classified according to the European Medicines Agency (EMEA) algorithm.

RESULTS

The number of incident cases of AAV in Japan and the U.K. were 86 and 50, respectively, and the average annual incidence over the 5-year period was 22.6/million (95% CI 19.1, 26.2) and 21.8/million (95% CI 12.6, 30.9) in Japan and the U.K., respectively. The average age was higher in patients in Japan than in patients in the U.K. [mean (median), 69.7 (72) vs. 60.5 (61) years]. Microscopic polyangiitis (MPA) was the predominant subtype in Japan (83%), while granulomatosis with polyangiitis (Wegener's) was more frequent in the U.K. (66%). As for the pattern of ANCA positivity, >80% of Japanese patients were pANCA/MPO positive, whereas two-thirds of U.K. patients were cANCA/PR3 positive. Renal involvement in MPA was very common in both countries, but was much less common in granulomatosis with polyangiitis in Japan compared with the U.K.

CONCLUSION

There was no major difference in AAV incidence between Japan and the U.K., but this prospective study found MPA and MPO-ANCA to be more common in Japan and granulomatosis with polyangiitis and PR3-ANCA to be more common in the U.K., in line with earlier reports.

Comparison of the epidemiology of anti-neutrophil cytoplasmic antibody-associated vasculitis between Japan and the U.K

OBJECTIVES

The epidemiological manifestations of ANCA-associated vasculitis (AAV) differ geographically. However, there have been no prospective studies comparing the incidence of AAV between Japan and Europe over the same time period using the same case definitions.

METHODS

The incidence of AAV was determined by a population-based method in Miyazaki prefecture, Japan, and Norfolk, U.K., between 2005 and 2009. Patients with AAV were defined and classified according to the European Medicines Agency (EMEA) algorithm.

RESULTS

The number of incident cases of AAV in Japan and the U.K. were 86 and 50, respectively, and the average annual incidence over the 5-year period was 22.6/million (95% CI 19.1, 26.2) and 21.8/million (95% CI 12.6, 30.9) in Japan and the U.K., respectively. The average age was higher in patients in Japan than in patients in the U.K. [mean (median), 69.7 (72) vs. 60.5 (61) years]. Microscopic polyangiitis (MPA) was the predominant subtype in Japan (83%), while granulomatosis with polyangiitis (Wegener's) was more frequent in the U.K. (66%). As for the pattern of ANCA positivity, >80% of Japanese patients were pANCA/MPO positive, whereas two-thirds of U.K. patients were cANCA/PR3 positive. Renal involvement in MPA was very common in both countries, but was much less common in granulomatosis with polyangiitis in Japan compared with the U.K.

CONCLUSION

There was no major difference in AAV incidence between Japan and the U.K., but this prospective study found MPA and MPO-ANCA to be more common in Japan and granulomatosis with polyangiitis and PR3-ANCA to be more common in the U.K., in line with earlier reports.

C-MYC rearrangement may induce an aggressive phenotype in anaplastic lymphoma kinase positive anaplastic large cell lymphoma: Identification of a novel fusion gene ALO17/C-MYC

Anaplastic lymphoma kinase (ALK) positive anaplastic large cell lymphoma (ALCL) is usually associated with a favorable prognosis. We describe an 11-year-old girl patient with ALK positive ALCL bearing t(2;5)(p23;q35) and t(8;17)(q24;q25) translocations who had an aggressive clinical course despite various combinations of intensive chemotherapy. Southern blot analysis identified C-MYC rearrangement. Immunohistochemistry and Northern and Western blot analyses revealed cmyc overexpression. A new fusion between ALO17 (ALK lymphoma oligomerization partner on chromosome 17) and C-MYC was identified by the 50-rapid amplification of cDNA ends. This new fusion may have possibly provoked the poor prognosis in this patient with ALK positive ALCL, and C-MYC rearrangement may indicate poor prognosis in ALCL.

Hematologically important mutations: X-linked chronic granulomatous disease (third update)

Chronic granulomatous disease (CGD) is an immunodeficiency disorder affecting about 1 in 250,000 individuals. The disease is caused by a lack of superoxide production by the leukocyte enzyme NADPH oxidase. Superoxide is used to kill phagocytosed micro-organisms in neutrophils, eosinophils, monocytes and macrophages. The leukocyte NADPH oxidase is composed of five subunits, of which the enzymatic component is gp91-phox, also called Nox2. This protein is encoded by the CYBB gene on the X chromosome. Mutations in this gene are found in about 70% of all CGD patients. This article lists all mutations identified in CYBB in the X-linked form of CGD. Moreover, apparently benign polymorphisms in CYBB are also given, which should facilitate the recognition of future disease-causing mutations.

Successful treatment of refractory donor lymphocyte infusion-induced immune-mediated pancytopenia with rituximab

A 6-year-old male with chronic granulomatous disease, who was transplanted with bone marrow and exhibited increasing mixed chimerism, subsequently received two donor lymphocyte infusions (DLI). Two weeks after the second DLI, the patient developed acute graft-versus-host disease (GVHD) and progressive pancytopenia that was associated with autoantibody production. Conventional treatment did not improve the pancytopenia. However, administration of Rituximab (RTX) (375 mg/m(2)/week for four consecutive weeks) resulted in a rapid resolution of the pancytopenia. The patient achieved full donor chimerism without GVHD symptoms. RTX can be valuable for managing immune-mediated cytopenias that arise after DLI and are refractory to conventional therapies.

Cytomegalovirus infection mimicking juvenile myelomonocytic leukemia showing hypersensitivity to granulocyte-macrophage colony stimulating factor

We describe an infant with cytomegalovirus (CMV) infection presenting as transient myeloproliferation resembling juvenile myelomonocytic leukemia (JMML). The patient fulfilled the international diagnostic criteria of JMML, including hypersensitivity to granulocyte-macrophage colony-stimulating factor (GM-CSF). Viral studies using serologic assays and polymerase chain reaction (PCR) were positive for CMV. Clinical symptoms disappeared and laboratory values returned to normal without specific treatment within 1 year. Follow-up showing a decrease in viral titers suggested CMV infection as an etiologic factor for the development of myeloproliferative features. We conclude that the CMV infection transiently induced abnormal myelopoiesis in this infant.

Risk parameters of fulminant acute respiratory distress syndrome and avian influenza (H5N1) infection in Vietnamese children

A clinical picture of patients with acute respiratory distress syndrome (ARDS) induced by highly pathogenic avian influenza A (H5N1) has been reported. We reviewed 37 sets of clinical data for pediatric patients with ARDS at the National Hospital of Pediatrics (Hanoi, Vietnam); 12 patients with H5N1-positive and 25 with H5N1-negative ARDS were enrolled. The H5N1-negative patients had a clinical picture and mortality rate similar to that for the pediatric ARDS patients. However, the H5N1-positive patients had ARDS with normal ventilation capacity at the time of hospital admission, then rapidly proceeded to severe respiratory failure. The survival probability and days until final outcome in groups of H5N1-positive (n=12) vs. H5N1-negative (n=25) patients were 17% versus 52% and 12.3+/-5.7 days (median, 11 days) versus 21.5+/-13.8 days (median, 22 days), respectively. Our observations clarified the clinical picture of H5N1-induced fulminant ARDS and also confirmed that relatively older age (approximately 6 years of age), high fever at onset, and leukopenia and/or thrombocytopenia at the time of hospital admission are risk parameters for H5N1-induced fulminant ARDS.

Segawa disease with a novel heterozygous mutation in exon 5 of the GCH-1 gene (E183K)

We report a novel missense mutation in the GCH-1 gene resulting in Segawa disease. The patient, a 6-year-old girl, presented with dystonia. Her CSF biopterin and neopterin levels were reduced, suggesting Segawa disease. L-dopa administration led to clinical improvement. Genetic analysis revealed a missense mutation in exon 5 of the GCH-1 gene (E183K). Although dystonia or other movement disorders were not identified in her family, this may be explained by the low penetrance of Segawa disease.

Adult onset X-linked chronic granulomatous disease in a woman patient caused by a de novo mutation in paternal-origin CYBB gene and skewed inactivation of normal maternal X chromosome

We report a 28-year-old woman patient suffering from refractory subcutaneous abscess. Stimuli-induced microbicidal reactive oxygen metabolites formation test of the patient's neutrophils revealed that only 9.6% of the neutrophils produced H2O2. DNA analysis of the CYBB that encodes gp91(phox) demonstrated that she was heterozygous for a nonsense mutation, 206Trp(TGG)/stop(TGA) and therefore, a diagnosis of adult onset X-linked chronic granulomatous disease was made. Our molecular biological study revealed that her disease was caused by a de novo mutation in the CYBB gene on the paternal-origin X-chromosome and a skewed inactivation of the normal maternal X-chromosome.

[Two breakthroughs in CGD studies]

Studies in Chronic Granulomatous Disease showed two breakthroughs during this past decade. First, the discovery of 7 Nox/Duox family proteins, Noxo1 and Noxa1 (homologues of gp91(phox), p47(phox) and p67(phox)) may clarify novel physiological mechanisms for superoxide regulation in various organs, such as the regulation of blood pressure, mucosal defense system in respiratory/digestive tract and nephron. Secondly, the success in bone marrow transplantation and gene therapy for CGD should facilitate treatment for other genetic diseases as well.

Outcome of ANCA-associated primary renal vasculitis in Miyazaki Prefecture

OBJECT

We examined the prognosis of patients with onset of new primary renal vasculitis (PRV) in Miyazaki Prefecture.

PATIENTS AND METHODS

We enrolled and followed-up 56 patients (age, 70.4 +/- 10.9 years, mean +/- SD) with onset of new PRV between January 2000 and December 2004, for a median of 24 months. Patients with PRV were defined according to the EUVAS (European Systemic Vasculitis Study Group) criteria. Outcome and factors predicting unfavorable outcome of death were examined.

RESULTS

Among the patients, 25% (n=14) required dialysis therapy immediately at the start of immunosuppressive therapy and of these, renal function recovered in only 3 and 6 died during the first admission. On the other hand, 75% (n=42) did not require immediate dialysis, but 8 patients were introduced to dialysis therapy thereafter. At the end of follow-up, 26 (46%) had survived without dialysis, 10 (18%) were dependent on dialysis and 20 (36%) had died. Infection was the major cause of death (n=11) . The Cox proportional hazards model showed that the presence of lung lesions and immediate dialysis therapy conferred poorer survival rates (HR, 3.32, 95% CI, 1.14 to 9.71; HR 2.73, 95% CI, 1.03 to 7.23, respectively).

CONCLUSION

A poor survival rate is independently associated with the presence of lung lesions and advanced renal failure at the start of immunosuppressive therapy in patients with PRV. Half of the deaths were due to infection. Thus, PRV should be identified at an early stage and the treatment protocol should prevent infectious complications. These measures should improve the prognosis of patients with PRV.

Incidence of ANCA-Associated Primary Renal Vasculitis in the Miyazaki Prefecture: The First Population-Based, Retrospective, Epidemiologic Survey in Japan

Clinicoepidemiological manifestations of the vasculitides differ geographically. According to a nationwide, hospital-based survey in Japan, the prevalence of microscopic polyangiitis (MPA) and/or renal-limited vasculitis (RLV) is much higher than that of Wegener's granulomatosis (WG). However, little is known about the incidence of antineutrophil cytoplasmic autoantibodies (ANCA)-associated primary renal vasculitis (PRV) in Japan. The incidence of PRV was retrospectively determined by a population-based method in Miyazaki Prefecture in Japan between 2000 and 2004. PRV was defined according to the following criteria from the European Systemic Vasculitis Study Group: (1) new patients with WG, MPA, Churg-Strauss syndrome (CSS), or RLV, (2) renal involvement attributable to active vasculitis, and (3) ANCA considered positive if the disease was not histologically confirmed. The numbers of patients with PRV in the years 2000, 2001, 2002, 2003, and 2004 were 9, 9, 9, 16, and 13, respectively. The male to female ratio was 24:32 and the average age was 70.4 +/- 10.9 (mean +/- SD) yr. The estimated annual incidence of PRV was 14.8 (95% confidence interval [CI] 10.8 to 18.9) and 44.8 (95% CI 33.2 to 56.3) per million adults (>15 yr old) and seniors (>65 yr old), respectively. Ninety-one percent of the patients were myeloperoxidase (MPO)-ANCA positive, but none were positive for proteinase 3 (PR3)-ANCA. There were no WG or CSS patients. The incidence of PRV did not differ between Japan and Europe, but WG was not widespread in Japan. Furthermore, the ratio of serum MPO to PR3-ANCA among Japanese with PRV was much higher than that found among European and US patients.

Prognostic predictive values of serum cytochrome c, cytokines, and other laboratory measurements in acute encephalopathy with multiple organ failure

AIMS

To evaluate the prognostic predictive values of cytochrome c, cytokines, and other laboratory measurements in serum collected during neurological onset in acute encephalopathy with multiple organ failure.

METHODS

In addition to general laboratory examinations, the concentrations of cytochrome c (apoptosis marker) and cytokines (inflammatory markers) were measured in serum samples collected at the initial phase in 29 patients with acute encephalopathy. The obtained values were evaluated as predictors for the development of severe encephalopathy.

RESULTS

Cytochrome c, tumour necrosis factor alpha (TNF-alpha), interleukin 6 (IL-6), soluble TNF-receptor 1 (sTNF-R1), and aspartate aminotransferase (AST) concentrations at the initial phase were high and correlated well with patient outcome. High concentrations of serum cytochrome c (>45 ng/ml), sTNF-R1 (>2000 pg/ml), AST (>58 IU/dl), IL-6 (>60 pg/ml), and TNF-alpha (>15 pg/ml) predicted an unfavourable prognosis (sequelae and death) at 93%, 79%, 82%, 77%, and 60%, respectively. The specificity of those markers was 100%, 89%, 83%, 100%, and 100%, respectively.

CONCLUSIONS

Serum cytochrome c is the most sensitive and specific predictor for the development of severe encephalopathy at the initial phase. Results suggest that this marker might be used to guide decisions regarding the start of the initial treatment and further intensive care.