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Myeloid/natural killer (NK) cell precursor acute leukemia (MNKPL) has been described based on its clinical phenotype and immunophenotype, and proposed as a unique leukemia entity. However, due to its rarity and lack of defined distinctive molecular characteristics, there is currently no international consensus on this disease concept. We performed multi-omics analysis and revealed that MNKPL is distinct from acute myeloid leukemia, T-cell acute lymphoblastic leukemia, and mixed-phenotype acute leukemia. NOTCH1 and RUNX3 activation and BCL11B downregulation are hallmarks of MNKPL. Although NK cells have been classically considered to be lymphoid lineage-derived, our single-cell analysis using MNKPL cells suggested that NK cells and myeloid cells share common progenitor cells. Our retrospective case study uncovered that outcomes of MNKPL are unsatisfactory, even with hematopoietic cell transplantation. Multi-omics analysis and in vitro drug sensitivity assays revealed increased sensitivity to L-asparaginase and reduced levels of asparagine synthetase, supporting the clinically observed effectiveness of L-asparaginase.
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Células Asesinas Naturales , Humanos , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/metabolismo , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapiaRESUMEN
Organometallic tin-oxo-hydroxo cage compounds offer a promising photoresist platform for extreme ultraviolet photolithography (EUVL). Their reactivity is dominated by the facile breaking of the tin-carbon bonds upon photon or electron irradiation. As the cage is dicationic, it exists as a complex with anions for charge compensation. In the present work, we explore the n-butyltin-oxo cage with two tetrakis(pentafluorophenyl)borate counteranions (TinPFPB). In contrast to the small counterions that are typically used, the bulky PFPB anion absorbs a substantial fraction (â¼30%) of the impinging EUV radiation (13.5 nm, 92 eV), and it has its own reactivity upon photoionization. When thin films of the complex are irradiated with EUV radiation at low doses, a positive-tone development is possible, which is rather unique as all other known tin-oxo cage resists show a negative tone (cross-linking) behavior. We propose that the initial positive tone behavior is a result of the chemical modification of the Sn cluster by fragments of the borate anions. For comparison, we include the tetrakis(p-tolyl)borate anion (TB) in the study, which has similar bulkiness, and its complex with the n-butyltin-oxo cage (TinTB) shows the usual negative tone EUV resist behavior. This negative-tone behavior for our control experiment rules out a hypothesis based purely on the steric hindrance of the anion as the cause of the different EUV reactivity.
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We diagnosed six cases of acute hepatitis C virus (HCV) infection at our hospital between October 2003 and December 2022. During the same period, we diagnosed 402 cases of chronic HCV infection and 636 cases of acute hepatic injury. Acute HCV infection cases accounted for 1.4% of all HCV infections and 0.9% of all acute hepatic injury cases. The acute HCV infection group was younger, had more severe hepatitis, and exhibited higher levels of bilirubinemia compared to the chronic HCV infection group. Two acute HCV infection cases achieved spontaneous viral clearance, while the remaining four cases progressed to chronic infection and were treated with direct-acting antivirals (DAAs). Liver enzyme elevation and liver function deterioration did not differ significantly between the acute HCV and other acute liver injury groups. Notably, DAA treatment was equally effective for acute and chronic HCV cases (75% vs. 90%, p = 0.34). Early DAA treatment in acute cases might contribute to interrupting viral transmission among high-risk populations, such as people who inject drugs or men who have sex with men. While there are currently no specific guidelines for acute HCV infection treatment in Japan, our findings suggest that DAA therapy should be initiated immediately following diagnosis. Further studies with larger patient cohorts are warranted to confirm these observations.
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Human adenovirus infection (HAdV) may be fatal in patients undergoing allogeneic hematopoietic cell transplantation (HCT). Cidofovir is effective in only a part of the post-HCT HAdV infection. Therefore, posttransplant immune reconstitution is important for HAdV clearance. We describe the detailed immune reconstitution and response of adenovirus-specific T cells in a patient with inborn errors of immunity who had disseminated HAdV infection with hepatitis post-HCT and was treated with cidofovir. Though the patient received cidofovir for only 19 days starting from Day 72 after HCT because of renal dysfunction, we observed T-cell reconstitution, a decrease in HAdV copy number, and amelioration of the symptoms of HAdV infection after Day 90. We initially observed expanded NK and CD8+CD45RO+ memory subsets and later gradual increase of naïve T cells eveloped after cessation of cidofovir treatment. An increase in adenovirus-specific IFN-γ secretion from 2 to 4 months after HCT was confirmed by ELISpot assay. The progression of immune reconstitution and cidofovir treatment are considered to have contributed to survival in this patient. Optimization of transplantation methods, prompt appropriate antiviral medication, and virus-specific T-cell therapy would be necessary as the better strategy for systemic HAdV infection.
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Infecciones por Adenovirus Humanos , Antivirales , Cidofovir , Citosina , Trasplante de Células Madre Hematopoyéticas , Reconstitución Inmune , Organofosfonatos , Humanos , Cidofovir/uso terapéutico , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Organofosfonatos/uso terapéutico , Citosina/análogos & derivados , Citosina/uso terapéutico , Infecciones por Adenovirus Humanos/tratamiento farmacológico , Infecciones por Adenovirus Humanos/inmunología , Infecciones por Adenovirus Humanos/terapia , Antivirales/uso terapéutico , Trasplante Homólogo , Adenovirus Humanos/inmunología , Masculino , Hepatitis Viral Humana/tratamiento farmacológico , Hepatitis Viral Humana/inmunologíaRESUMEN
The arginine transporter Can1 is a multifunctional protein of the conventional yeast Saccharomyces cerevisiae. Apart from facilitating arginine uptake, Can1 plays a pivotal role in regulating proline metabolism and maintaining cellular redox balance. Here, we report a novel function of Can1 in the control of yeast biofilm formation. First, the S. cerevisiae CAN1 gene knockout strain displayed a significant growth delay compared to the wild-type strain. Our genetic screening revealed that the slow growth of the CAN1 knockout strain is rescued by a functional deficiency of the FLO8 gene, which encodes the master transcription factor associated with biofilm formation, indicating that Can1 is involved in biofilm formation. Intriguingly, the CAN1 knockout strain promoted the Flo11-dependent aggregation, leading to higher biofilm formation. Furthermore, the CAN1 knockout strain of the pathogenic yeast Candida glabrata exhibited slower growth and higher biofilm formation, similar to S. cerevisiae. More importantly, the C. glabrata CAN1 gene knockout strain showed severe toxicity to macrophage-like cells and nematodes. The present results could help to elucidate both the molecular mechanism underlying yeast biofilm formation and the role it plays. Future investigations may offer insights that contribute to development of antibiofilm agents.
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Alemtuzumab is used with reduced-toxicity conditioning (RTC) in allogeneic hematopoietic cell transplantation (HCT), demonstrating efficacy and feasibility for patients with inborn errors of immunity (IEI) in Western countries; however, the clinical experience in Asian patients with IEI is limited. We retrospectively analyzed patients with IEI who underwent the first allogeneic HCT with alemtuzumab combined with RTC regimens in Japan. A total of 19 patients were included and followed up for a median of 18 months. The donors were haploidentical parents (n = 10), matched siblings (n = 2), and unrelated bone marrow donors (n = 7). Most patients received RTC regimens containing fludarabine and busulfan and were treated with 0.8 mg/kg alemtuzumab with intermediate timing. Eighteen patients survived and achieved stable engraftment, and no grade 3-4 acute graft-versus-host disease was observed. Viral infections were observed in 11 patients (58%) and 6 of them presented symptomatic. The median CD4+ T cell count was low at 6 months (241/µL) but improved at 1 year (577/µL) after HCT. Whole blood cells continued to exhibit > 80% donor type in most cases; however, 3/10 patients exhibited poor donor chimerism only among T cells and also showed undetectable levels of T-cell receptor recombination excision circles (TRECs) at 1 year post-HCT. This study demonstrated the efficacy and safety of alemtuzumab; however, patients frequently developed viral infections and slow reconstitution or low donor chimerism in T cells, emphasizing the importance of monitoring viral status and T-cell-specific chimerism. (238 < 250 words).
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Alemtuzumab , Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Acondicionamiento Pretrasplante , Trasplante Homólogo , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Alemtuzumab/uso terapéutico , Pueblo Asiatico , Enfermedad Injerto contra Huésped/etiología , Trasplante de Células Madre Hematopoyéticas/métodos , Estudios Retrospectivos , Acondicionamiento Pretrasplante/métodos , Resultado del Tratamiento , Japón , Enfermedades del Sistema Inmune/genéticaRESUMEN
Humans and mammals need to ingest essential amino acids (EAAs) for protein synthesis. In addition to their importance as nutrients, EAAs are involved in brain homeostasis. However, elderly people are unable to efficiently consume EAAs from their daily diet due to reduced appetite and variations in the contents of EAAs in foods. On the other hand, strains of the yeast Saccharomyces cerevisiae that accumulate EAAs would enable elderly people to intakegest adequate amounts of EAAs and thus might slow down the neurodegenerative process, contributing to the extension of their healthy lifespan. In this study, we isolated a mutant (strain HNV-5) that accumulates threonine, an EAA, derived from a diploid laboratory yeast by conventional mutagenesis. Strain HNV-5 carries a novel mutation in the HOM3 gene encoding the Ala462Thr variant of aspartate kinase (AK). Enzymatic analysis revealed that the Ala462Thr substitution significantly decreased the sensitivity of AK activity to threonine feedback inhibition even in the presence of 50 mM threonine. Interestingly, Ala462Thr substitution did not affect the catalytic ability of Hom3, in contrast to previously reported amino acid substitutions that resulted in reduced sensitivity to threonine feedback inhibition. Furthermore, yeast cells expressing the Ala462Thr variant showed an approximately threefold increase in intracellular threonine content compared to that of the wild-type Hom3. These findings will be useful for the development of threonine-accumulating yeast strains that may improve the quality of life in elderly people.IMPORTANCEFor humans and mammals, essential amino acids (EAAs) play an important role in maintaining brain function. Therefore, increasing the intake of EAAs by using strains of the yeast Saccharomyces cerevisiae that accumulate EAAs may inhibit neurodegeneration in elderly people and thus contribute to extending healthy lifespan and improving their quality of life. Threonine, an EAA, is synthesized from aspartate. Aspartate kinase (AK) catalyzes the first step in threonine biosynthesis and is subject to allosteric regulation by threonine. Here, we isolated a threonine-accumulating mutant of S. cerevisiae by conventional mutagenesis and identified a mutant gene encoding a novel variant of AK. In contrast to previously isolated variants, the Hom3 variant exhibited AK activity that was insensitive to feedback inhibition by threonine but retained its catalytic ability. This resulted in increased production of threonine in yeast. These findings open up the possibility for the rational design of AK to increase threonine productivity in yeast.
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Aspartato Quinasa , Saccharomyces cerevisiae , Humanos , Animales , Anciano , Saccharomyces cerevisiae/metabolismo , Treonina , Aspartato Quinasa/química , Aspartato Quinasa/genética , Aspartato Quinasa/metabolismo , Retroalimentación , Calidad de Vida , MamíferosRESUMEN
A female patient was referred to our hospital with complaints of liver injury. She had been treated for immunoglobulin (Ig)A nephropathy using prednisolone and other medications. Drug-induced liver injury (DILI) was suspected, as no evidence of viral infection or autoimmune liver disease was apparent. All medications except for prednisolone were discontinued, but liver enzyme levels remained elevated. Percutaneous liver biopsy showed the characteristics of DILI and drug lymphocyte stimulation testing yielded positive results for prednisolone. After stopping administration of prednisolone, liver enzyme levels recovered to near-normal. Prednisolone has immunosuppressive effects and is sometimes used to treat DILI. Some reports have revealed that high-dose corticosteroids can induce liver injury, but liver injuries associated with low-dose corticosteroid therapy have not been described. Prednisolone-induced liver injury is a rare phenomenon. When low-dose corticosteroids are used for treatment, care should be taken regarding the possibility of liver injury.
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A 49-year-old man with abdominal pain was referred to our hospital. Abdominal computed tomography showed an extraluminal tumor near the gastric anterior wall and intra-abdominal fluid collection. A ruptured intra-abdominal tumor was suspected, and emergency abdominal angiography was performed. Hemorrhage into the abdominal cavity was seen, and transcatheter arterial embolization (TAE) was performed, which stopped the bleeding. The tumor was surgically resected, and a diagnosis of an extraluminally growing gastric gastrointestinal stromal tumor was made. TAE should be considered for rare cases of extraluminally growing tumors with intra-abdominal hemorrhage.
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Supersulfides, which are defined as sulfur species with catenated sulfur atoms, are increasingly being investigated in biology. We recently identified pyridoxal phosphate (PLP)-dependent biosynthesis of cysteine persulfide (CysSSH) and related supersulfides by cysteinyl-tRNA synthetase (CARS). Here, we investigated the physiological role of CysSSH in budding yeast (Saccharomyces cerevisiae) by generating a PLP-binding site mutation K109A in CRS1 (the yeast ortholog of CARS), which decreased the synthesis of CysSSH and related supersulfides and also led to reduced chronological aging, effects that were associated with an increased endoplasmic reticulum stress response and impaired mitochondrial bioenergetics. Reduced chronological aging in the K109A mutant could be rescued by using exogenous supersulfide donors. Our findings indicate important roles for CARS in the production and metabolism of supersulfides-to mediate mitochondrial function and to regulate longevity.
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Longevidad , Proteínas de Saccharomyces cerevisiae , Mitocondrias/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Azufre/metabolismoRESUMEN
AIM: To determine the apparent diffusion coefficient (ADC) in brain structures during the first 2 weeks of life and its relation with neurological outcome for hypoxic-ischaemic encephalopathy (HIE) in term neonates. METHODS: We retrospectively evaluated 56 term-born neonates. The ADC values were measured for 11 brain regions. The clinical outcomes at least 2 years of age were defined as normal outcome, mild disability and severe disability. The area under curves (AUCs) by ROC analysis were performed to predict the neurodevelopmental outcomes. The clinical outcomes were compared between favourable outcome and adverse outcome and also between normal outcome and unfavourable outcome. RESULTS: Thirty-four patients were judged as normal outcome, 10 as mild disability and 12 as severe disability. When the clinical outcomes were compared between favourable outcome and adverse outcome, the AUC on the 1st week was highest value at the thalamus. When the clinical outcomes were compared between normal outcome and unfavourable outcome, the AUC on the 1st week was highest at the thalamus. CONCLUSION: The ADC values in the thalamus in the 1st week can predict the neurological outcome. The ADC values in centrum semiovale on the 2nd week can be used to predict neurodevelopmental outcomes.
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Hipoxia-Isquemia Encefálica , Recién Nacido , Humanos , Estudios Retrospectivos , Hipoxia-Isquemia Encefálica/diagnóstico por imagen , Imagen de Difusión por Resonancia Magnética , Encéfalo , Curva ROC , Imagen por Resonancia MagnéticaRESUMEN
Arginine is a proteinogenic amino acid that organisms additionally exploit both for nitrogen storage and as a stress protectant. The location of arginine, whether intra- or extracellular, is important in maintaining physiological homeostasis. Here, we identified an arginine transporter ortholog of the emerging fungal pathogenic Candida glabrata. Blast searches revealed that the C. glabrata genome contains two potential orthologs of the Saccharomyces cerevisiae arginine transporter gene CAN1 (CAGL0J08162g and CAGL0J08184g). We then found that CAGL0J08162g is stably located on the plasma membrane and performs cellular uptake of arginine. Moreover, CAGL0J08162-disrupted cells of C. glabrata showed a partial resistance to canavanine, a toxic analog of arginine. Our data suggest that CAGL0J08162g is a key arginine transporter in the pathogenic C. glabrata (CgCan1).
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Candida glabrata , Proteínas Fúngicas , Candida glabrata/genética , Candida glabrata/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Arginina/metabolismo , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Regulación Fúngica de la Expresión GénicaRESUMEN
The quality of alcoholic beverages strongly depends on the metabolic characteristics of the yeast cells being used. To control the aroma and the taste of alcoholic beverages, as well as the production of ethanol in them, it is thus crucial to select yeast cells with the proper characteristics. Grape must contain a high concentration of proline, an amino acid that can potentially be a useful nitrogen source. However, Saccharomyces cerevisiae cannot utilize proline during the wine-making process, resulting in the elevated levels of proline in wine and consequent negative effects on wine quality. In this article, I review and discuss recent discoveries about the inhibitory mechanisms and roles of proline utilization in yeast. The information can help in developing novel yeast strains that can improve fermentation and enhance the quality and production efficiency of wine.
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Vitis , Vino , Saccharomyces cerevisiae/metabolismo , Prolina/metabolismo , Vino/análisis , Bebidas Alcohólicas , FermentaciónRESUMEN
Myeloid/natural killer (NK) cell precursor acute leukemia (MNKPL) has been described on the basis of its unique immunophenotype and clinical phenotype. However, there is no consensus on the characteristics for identifying this disease type because of its rarity and lack of defined distinctive molecular characteristics. In this study, multiomics analysis revealed that MNKPL is distinct from acute myeloid leukemia, T cell acute lymphoblastic leukemia, and mixed-phenotype acute leukemia (MPAL), and NOTCH1 and RUNX3 activation and BCL11B down-regulation are hallmarks of MNKPL. Although NK cells have been classically considered to be lymphoid lineage-derived, the results of our single-cell analysis using MNKPL cells suggest that NK cells and myeloid cells share common progenitor cells. Treatment outcomes for MNKPL are unsatisfactory, even when hematopoietic cell transplantation is performed. Multiomics analysis and in vitro drug sensitivity assays revealed increased sensitivity to l-asparaginase and reduced levels of asparagine synthetase (ASNS), supporting the clinically observed effectiveness of l-asparaginase.
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Asparaginasa , Leucemia Mieloide Aguda , Humanos , Leucemia Mieloide Aguda/terapia , Enfermedad Aguda , Células Asesinas Naturales , Resultado del Tratamiento , Proteínas Represoras , Proteínas Supresoras de TumorRESUMEN
Although proline is the most or second most abundant amino acid in wort and grape must, it is not fully consumed by the yeast Saccharomyces cerevisiae during alcoholic fermentation, unlike other amino acids. Our previous studies showed that arginine, the third most abundant amino acid in wort, inhibits the utilization of proline in most strains of S. cerevisiae. Furthermore, we found that some non-Saccharomyces yeasts utilized proline in a specific artificial medium with arginine and proline as the only nitrogen source, but these yeasts were not suitable for beer fermentation due to their low alcohol productivity. For yeasts to be useful for brewing, they need to utilize proline and produce alcohol during fermentation. In this study, 11 S. cerevisiae strains and 10 non-Saccharomyces yeast strains in the Phaff Yeast Culture Collection were identified that utilize proline effectively. Notably, two of these S. cerevisiae strains, UCDFST 40-144 and 68-44, utilize proline and produce sufficient alcohol in the beer fermentation model used. These strains have the potential to create distinctive beer products that are specifically alcoholic but with a reduction in proline in the finished beer.
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Two patients were incidentally diagnosed with intra-abdominal lymphadenopathy on imaging examinations. Although endoscopic ultrasound-guided fine needle aspiration of these areas of lymphadenopathy was performed, their causes remained undetermined. Neither patients had abnormal hepatic enzyme levels at the time lymphadenopathy was detected, but they developed hepatitis 20 months and five months later, respectively. The laboratory data and/or histopathological findings suggested primary biliary cholangitis/cirrhosis (PBC) and autoimmune hepatitis (AIH), respectively. These two patients were each started on appropriate treatment (ursodeoxycholic acid or prednisolone, respectively), their hepatitis ameliorated, and the hepatic enzyme levels recovered to within the normal ranges. These patients' clinical courses suggest that their lymphadenopathy was associated with PBC or AIH and appeared before the causative hepatitis became clinically apparent. We should consider the possibility of latent autoimmune hepatic diseases in cases with cryptogenic intra-abdominal lymphadenopathy even if there is no clinically apparent hepatitis.
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Proline, which is a predominant amino acid in grape musts, is involved in the taste and flavor of foods and beverages. The yeast Saccharomyces cerevisiae poorly utilizes proline in wine-making processes, leading to a nitrogen deficiency during fermentation and proline accumulation in wine. Previous studies have shown that the protein kinase A (PKA) pathway is involved in inhibitory mechanisms of proline utilization. In this study, we screened the PKA pathway-related genes that regulate proline utilization. Using a yeast culture collection of disrupted strains associated with the downstream of the PKA cascade, we revealed that the stress-responsive transcription factor genes MSN2/4 regulate proline utilization. Moreover, we found that Msn2/4 up-regulate the SHY1 gene during the cell growth of the wine fermentation model, which may cause the inhibition of proline utilization. The SHY1-deleted strain of the commercial wine yeast clearly showed proline consumption and average ethanol production under the wine fermentation model. The present data indicate that the PKA-Msn2/4-Shy1 cascade controls the inhibition of proline utilization under wine-making processes. Our study could hold promise for the development of wine yeast strains that can efficiently reduce proline during wine fermentation.
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Proteínas de Saccharomyces cerevisiae , Vino , Fermentación , Saccharomyces cerevisiae/metabolismo , Vino/análisis , Prolina/metabolismo , Aminoácidos/metabolismo , Proteínas de Unión al ADN/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismoRESUMEN
Abundant formation of endogenous supersulfides, which include reactive persulfide species and sulfur catenated residues in thiols and proteins (supersulfidation), has been observed. We found here that supersulfides catalyze S-nitrosoglutathione (GSNO) metabolism via glutathione-dependent electron transfer from aldehydes by exploiting alcohol dehydrogenase 5 (ADH5). ADH5 is a highly conserved bifunctional enzyme serving as GSNO reductase (GSNOR) that down-regulates NO signaling and formaldehyde dehydrogenase (FDH) that detoxifies formaldehyde in the form of glutathione hemithioacetal. C174S mutation significantly reduced the supersulfidation of ADH5 and almost abolished GSNOR activity but spared FDH activity. Notably, Adh5C174S/C174S mice manifested improved cardiac functions possibly because of GSNOR elimination and consequent increased NO bioavailability. Therefore, we successfully separated dual functions (GSNOR and FDH) of ADH5 (mediated by the supersulfide catalysis) through the biochemical analysis for supersulfides in vitro and characterizing in vivo phenotypes of the GSNOR-deficient organisms that we established herein. Supersulfides in ADH5 thus constitute a substantial catalytic center for GSNO metabolism mediating electron transfer from aldehydes.
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Aldehídos , Óxido Nítrico , Animales , Ratones , Transporte de Electrón , Catálisis , GlutatiónRESUMEN
PURPOSE: X-linked agammaglobulinemia (XLA) is an inborn error of immunity caused by variants in Bruton's tyrosine kinase (BTK). XLA patients require lifelong immunoglobulin replacement therapy (IgRT). Only few XLA patients are indicated for allogeneic hematopoietic cell transplantation (HCT) because of severe complications. Accordingly, the published transplantation experience in XLA is minimal. We aimed to collect clinical data of XLA patients who received HCT in an international framework and to establish appropriate transplantation criteria and methods for XLA patients. METHODS: XLA patients were recruited through a questionnaire and a literature review. The data are on patient characteristics and transplantation methods and outcomes. RESULTS: In this study, twenty-two XLA patients who underwent HCT were recruited. The indication for HCT was recurrent or life-threatening infection in sixteen patients, malignancy in three, and other factors in three. A myeloablative conditioning, reduced toxicity myeloablative conditioning (RT-MAC), and reduced intensity conditioning (RIC) were selected in four, ten, and eight patients, respectively. Engraftment was achieved in 21 patients (95%). In all patients, 2-year overall survival (OS) and event-free survival (EFS) were 86% and 77%, respectively. In patients who received RT-MAC or RIC using treosulfan, busulfan, or melphalan, 2-year OS and EFS were 82% and 71%, respectively. Finally, twenty-one patients (95%) obtained complete or stable high-level mixed chimerism (50-95%), and the 1-year discontinuation rate of IgRT was 89%. CONCLUSION: Based on the concept in which IgRT is the standard treatment for XLA, HCT may be an effective and safe alternative treatment option for XLA patients, and IgRT can be discontinued following transplantation. It is ideal to perform HCT in XLA patients for whom transplantation is indicated before they develop organ damage.