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.

Treatment with Polyethylene Glycol-Conjugated Fungal D-Amino Acid Oxidase Reduces Lung Inflammation in a Mouse Model of Chronic Granulomatous Disease.

Chronic granulomatous disease (CGD) is a primary immunodeficiency wherein phagocytes are unable to produce reactive oxygen species (ROS) owing to a defect in the nicotinamide adenine dinucleotide phosphate oxidase (NADPH) complex. Patients with CGD experience bacterial and fungal infections and excessive inflammatory disorders. Bone marrow transplantation and gene therapy are theoretically curative; however, residual pathogenic components cause inflammation and/or organic damage in patients. Moreover, antibiotic treatments may not help in preventing excessive inflammation due to the residual presence of fungal cell wall ß-glucan. Thus, better treatment strategies against CGD are urgently required. Polyethylene glycol-conjugated recombinant porcine D-amino acid oxidase (PEG-pDAO) supplies ROS to defective NADPH oxidase in neutrophils of patients with CGD, following which the neutrophils regain bactericidal activity in vitro. In this study, we employed an in vivo nonviable Candida albicans (nCA)-induced lung inflammation model of gp91-phox knockout CGD mice and supplied novel PEG conjugates of Fusarium spp. D-amino acid oxidase (PEG-fDAO), as it exhibits higher enzyme activity than PEG-pDAO. The body weight, lung weight, and lung pathology were evaluated using three experimental strategies with the in vivo lung inflammation model to test the efficacy of the ROS-generating enzyme replacement therapy with PEG-fDAO. The lung weight and pathological findings suggest the condition was ameliorated by administration PEG-fDAO, followed by intraperitoneal injection of D-phenylalanine or D-proline. Although a more precise protocol is essential, these data reveal the targeted delivery of PEG-fDAO to the nCA-induced inflammation site and show that PEG-fDAO can be used to treat inflammation in CGD in vivo.

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.

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 ß-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.

A hot-spot mutation in CDC42 (p.Tyr64Cys) and novel phenotypes in the third patient with Takenouchi-Kosaki syndrome.

Takenouchi-Kosaki syndrome (TKS) is a congenital malformation syndrome characterized by severe developmental delay, macrothrombocytopenia, camptodactyly, sensorineural hearing loss, and dysmorphic facial features. Recently, a heterozygous de novo mutation (p.Tyr64Cys) in the CDC42 gene, which encodes a key small GTP-binding protein of the Rho-subfamily, was identified in two unrelated patients with TKS. We herein report a third patient with TKS who had the same heterozygous CDC42 mutation. The phenotype of the patient was very similar to those of the two previously reported patients with TKS; however, she also demonstrated novel clinical manifestations, such as congenital hypothyroidism and immunological disturbance. Thus, despite the heterozygous mutation of CDC42 (p.Tyr64Cys) likely being a hot-spot mutation for TKS, its phenotype may be variable. Further studies and the accumulation of patients with CDC42 mutations are needed to clarify the phenotype in patients with TKS and the pathophysiological roles of the CDC42 mutation.

Necrotizing Ulcer After BCG Vaccination in a Girl With Leukocyte-adhesion Deficiency Type 1.

Leukocyte-adhesion deficiency-1 is a recessively inherited disorder associated with recurrent bacterial infections, severe periodontitis, peripheral leukocytosis, and impaired wound healing. We diagnosed moderate-type leukocyte-adhesion deficiency-1 in a 7-year-old girl who developed a necrotizing ulcer after Bacillus Calmette-Guerin vaccination. The patient showed moderate expression of CD18 in neutrophils with a homozygous splice mutation with c.41_c.58+2dup20 of ITGB2 and experienced recurrent severe infections complicated with systemic lupus erythematosus. She received hematopoietic stem cell transplantation from a matched elder brother with heterozygous mutation of ITGB2, and has since remained free of infection and systemic lupus erythematosus symptoms without immunosuppression therapy.

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.

TBCD may be a causal gene in progressive neurodegenerative encephalopathy with atypical infantile spinal muscular atrophy.

Spinal muscular atrophy (SMA) is an autosomal recessive neurodegenerative disorder caused by survival motor neuron gene mutations. Variant forms of SMA accompanied by additional clinical presentations have been classified as atypical SMA and are thought to be caused by variants in as yet unidentified causative genes. Here, we presented the clinical findings of two siblings with an SMA variant followed by progressive cerebral atrophy, and the results of whole-exome sequencing analyses of the family quartet that was performed to identify potential causative variants. We identified two candidate homozygous missense variants, R942Q in the tubulin-folding cofactor D (TBCD) gene and H250Q in the bromo-adjacent homology domain and coiled-coil containing 1 (BAHCC1) gene, located on chromosome 17q25.3 with an interval of 1.4 Mbp. The in silico analysis of both variants suggested that TBCD rather than BAHCC1 was likely the pathogenic gene (TBCD sensitivity, 0.68; specificity, 0.97; BAHCC1 sensitivity, 1.00; specificity, 0.00). Thus, our results show that TBCD is a likely novel candidate gene for atypical SMA with progressive cerebral atrophy. TBCD is predicted to have important functions on tubulin integrity in motor neurons as well as in the central nervous system.

A mouse model reveals that Mfsd2a is critical for unfolded protein response upon exposure to tunicamycin.

Major facilitator superfamily domain containing 2a (Mfsd2a) is a member of the major facilitator superfamily. Mfsd2a functions as a transporter for docosahexaenoic acid and also plays a role in the unfolded protein response (UPR) upon tunicamycin (TM) exposure. UPR is involved in the pathogenesis of various human diseases. TM and thapsigargin are representative experimental reagents that induce UPR. To elucidate the detailed function of Mfsd2a in UPR in vivo, we generated Mfsd2a-deficient mice and investigated the role of Mfsd2a during UPR induced by TM or thapsigargin. Phenotypically, Mfsd2a-deficient mice were small and short-lived. No gross anatomical abnormalities in Mfsd2a-deficient mice compared with the wild-type mice were exhibited. Embryonic fibroblasts derived from Mfsd2a-null mice failed to show induction of GRP78 and DDIT3 expressions upon TM exposure but not upon Tg exposure. This phenomenon could not be overcome despite the exposure under high TM concentration. Reconstitution of Mfsd2a in Mfsd2a-null MEF showed hypersensitivity to TM. Furthermore, we examined the physiological role of Mfsd2a against TM using an in vivo mouse model. DDIT3 induction by TM was drastically attenuated in both the liver and brain of Mfsd2a-deficient mice. These results reveal that Mfsd2a plays a critical role in UPR upon TM exposure.

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.