Intramural Duodenal Hematoma in a Case of Hyper IgM Syndrome.

Three-year-old boy who presented with colicky abdominal pain, diarrhoea and vomiting was investigated with computed tomography which revealed a mass in the peripancreatic region. An imaging possibility of duodenal intramural hematoma was considered after reassessment with ultrasound which was subsequently confirmed by magnetic resonance imaging. The development of a spontaneous duodenal hematoma lead to further evaluation of the patient and revealed X linked hyper IgM syndrome.

Clinical and Immunological Features, Genetic Variants, and Outcomes of Patients with CD40 Deficiency.

PURPOSE: Inherited deficiencies of CD40 and CD40 ligand (CD40L) reflect the crucial immunological functions of CD40-CD40L interaction/signaling. Although numerous studies have provided a detailed description of CD40L deficiency, reports of CD40 deficiency are scarce. Herein, we describe the characteristics of all reported patients with CD40 deficiency. METHODS: The PubMed, Embase and Web of Science databases were searched for relevant literature published till 7th August 2023. Study deduplication and identification of relevant reports was performed using the online PICO Portal. The data were extracted using a pre-designed data extraction form and the SPSS software was used for analysis. RESULTS: Systematic literature review revealed 40 unique patients with CD40 deficiency. Respiratory tract and gastrointestinal infections were the predominant clinical manifestations (observed in 93% and 57% patients, respectively). Sclerosing cholangitis has been reported in nearly one-third of patients. Cryptosporidium sp. (29%) and Pneumocystis jirovecii (21%) were the most common microbes identified. Very low to undetectable IgG levels and severely reduced/absent switch memory B cells were observed in all patients tested/reported. Elevated IgM levels were observed in 69% patients. Overall, splice-site and missense variants were the most common (36% and 32%, respectively) molecular defects identified. All patients were managed with immunoglobulin replacement therapy and antimicrobial prophylaxis was utilized in a subset. Hematopoietic stem cell transplantation (HSCT) has been performed in 45% patients (curative outcome observed in 73% of these patients). Overall, a fatal outcome was reported in 21% patients. CONCLUSIONS: We provide a comprehensive description of all important aspects of CD40 deficiency. HSCT is a promising curative treatment option for CD40 deficiency.

Advanced computational analysis of CD40LG variants in atypical X-linked hyper-IgM syndrome.

X-Linked Hyper-IgM Syndrome is caused by pathogenic variants in CD40LG. Three patients with atypical clinical and immunological features were identified with variants in CD40LG requiring further characterization. Flow cytometry was used to evaluate CD40L protein expression and binding capacity to a surrogate receptor, CD40-muIg. Though functional anomalies were observed, there was still a lack of clarity regarding the underlying mechanism. We developed structural models for wild-type and the three variants of CD40L protein observed in these patients (p. Lys143Asn, Leu225Ser and Met36Arg) to evaluate structural alterations by molecular mechanic calculations, and assess protein movement by molecular dynamic simulations. These studies demonstrate that functional analysis of variants of unknown significance in CD40LG can be supplemented by advanced computational analysis in atypical clinical contexts. These studies in combination identify the deleterious effects of these variants and potential mechanisms for protein dysfunction.

Elevated levels of enteric IgA in an unimmunised mouse model of Hyper IgM syndrome derived from gut-associated secondary lymph organs even in the absence of germinal centres.

Introduction: Patients with Human Hyper IgM syndromes (HIGM) developed pulmonary and gastrointestinal infections since infancy and most patients have mutations in the CD40 ligand (CD40L) gene. Most HIGM patients compared to healthy subjects have higher/similar IgM and lower IgG, and IgA serum concentrations but gut antibody concentrations are unknown. CD40L on activated T-cells interacts with CD40 on B-cells, essential for the formation of germinal centres (GCs) inside secondary lymphoid organs (SLOs), where high-affinity antibodies, long-lived antibody-secreting plasma cells, and memory B-cells, are produced. C57BL6-CD40 ligand deficient mice (C57BL6-cd40l -/-), are a model of HIGM, because serum immunoglobulin concentrations parallel levels observed in HIGM patients and have higher faecal IgA concentrations. In mice, TGFß and other cytokines induce IgA production. Aims: To compare and evaluate B-cell populations and IgA-producing plasma cells in peritoneal lavage, non-gut-associated SLOs, spleen/inguinal lymph nodes (ILN), and gut-associated SLOs, mesenteric lymph nodes (MLN)/Peyer´s patches (PP) of unimmunised C57BL6-cd40l -/- and C57BL6-wild-type (WT) mice. Material and methods: Peritoneal lavages, spleens, ILN, MLN, and PP from 8-10 weeks old C57BL6-cd40l -/- and WT mice, were obtained. Organ cryosections were analysed by immunofluorescence and B-cell populations and IgA-positive plasma cell suspensions by flow cytometry. Results: In unimmunised WT mice, GCs were only observed in the gut-associated SLOs, but GCs were absent in all C57BL6-cd40l -/- SLOs. PP and MLN of C57BL6-cd40l -/- mice exhibited a significantly higher number of IgA-producing cells than WT mice. In the spleen and ILN of C57BL6-cd40l- /- mice IgA-producing cells significantly decreased, while IgM-positive plasma cells increased. C57BL6-cd40l -/- B-1 cells were more abundant in all analysed SLOs, whereas in WT mice most B-1 cells were contained within the peritoneal cavity. C57BL6-cd40l -/- B-cells in MLN expressed a higher TGFß receptor-1 than WT mice. Mouse strains small intestine microvilli (MV), have a similar frequency of IgA-positive cells. Discussion: Together our results confirm the role of PP and MLN as gut inductive sites, whose characteristic features are to initiate an IgA preferential immune response production in these anatomical sites even in the absence of GCs. IgA antibodies play a pivotal role in neutralising, eliminating, and regulating potential pathogens and microorganisms in the gut.

CD40LG-associated X-linked Hyper-IgM Syndrome (XHIGM) with pulmonary alveolar proteinosis: a case report.

BACKGROUND: D40LG-associated X-linked hyper-IgM syndrome with pulmonary alveolar proteinosis has rarely been reported, and its genotype-phenotypic correlation remains elusive. CASE PRESENTATION: We describe a five-month-old boy with CD40LG mutation (c.516T > A, p.Tyr172Ter) X-linked hyper-IgM syndrome with pulmonary alveolar proteinosis as the first manifestation. The patient completely recovered after immunotherapy and allogeneic hematopoietic stem cell transplantation. In addition, four previously reported patients with CD40LG mutation with pulmonary alveolar proteinosis were also analyzed. All of these patients presented with early onset of pulmonary infections and a good response to immunotherapy. The structural model of CD40LG indicated that all mutations caused the X-linked hyper-IgM syndrome with pulmonary alveolar proteinosis to be located within the tumor necrosis factor homology domain. CONCLUSIONS: A case was presented, and the characteristics of four cases of CD40LG-associated X-linked hyper-IgM syndrome with pulmonary alveolar proteinosis were summarized. The variant locations may explain the phenotypic heterogeneity of patients with the CD40LG mutation.

[Hyper-IgM syndrome with early liver involvement]. / Síndrome de hiper-IgM con afectación hepática temprana.

INTRODUCTION: Hyper-IgM syndrome is an innate error of immunity in which there is a defect in change of isotype of immunoglobulins, with decreased values of IgG, IgA, and IgE, but normal or increased level of IgM. This predisposes to infectious processes at the respiratory and gastrointestinal levels, as well as autoimmune diseases and neoplasm. CASE REPORT: A 5 year 7-month-old boy with a history of 2 pneumonias, one of them severe, and chronic diarrhea since he was 2 years old. Persistent moderate neutropenia decreased IgG and elevated IgM. Cytometry flow confirmed absence of CD40L. Clinical evolution with early hepatic involvement. DISCUSSION: Hyper-IgM syndrome predisposes to liver damage, so a complete evaluation is required as well as early diagnosis. Active anti-infective treatment and control of the inflammatory response are key to the treatment of liver damage.

INTRODUCCIÓN: El síndrome de hiper-IgM es un error innato de la inmunidad, caracterizado por un defecto en el cambio de isotipo de inmunoglobulina, con valores disminuidos de IgG, IgA e IgE, y concentraciones normales o elevadas de IgM. Predispone a procesos infecciosos en el sistema respiratorio y aparato gastrointestinal, además de enfermedades autoinmunes y neoplasias. REPORTE DE CASO: Paciente pediátrico de género masculino, de 5 años y 7 meses de edad, con antecedente de dos cuadros de neumonía (uno de estos grave) y diarrea crónica desde los 2 años. Neutropenia moderada persistente, disminución de la concentración de IgG y elevación de IgM. La citometría de flujo confirmó la ausencia de CD40L. Durante la evolución clínica tuvo afectación hepática temprana. CONCLUSIÓn: El síndrome de hiper-IgM predispone a daño hepático, por lo que se requiere la evaluación completa y el diagnóstico oportuno. El tratamiento antiinfeccioso activo y el control de la respuesta inflamatoria son factores decisivos para establecer el tratamiento del daño hepático.

Respiratory infections in X-linked hyper-IgM syndrome with CD40LG mutation: a case series of seven children in China.

BACKGROUND: X-linked hyper-immunoglobulin M (XHIGM), a primary immunodeficiency syndrome caused by mutations in the CD40 ligand gene(CD40LG), presents with recurrent respiratory infections in pediatric patients. We aimed to evaluate the spectrum of clinical features and respiratory pathogens in pediatric patients with XHIGM in China. METHODS: We retrospectively reviewed seven pediatric patients who were diagnosed with XHIGM and received follow-up treatment at the Guangzhou Women and Children's Medical Center between January 2010 and January 2021. We determined their clinical characteristics, causative pathogens, and prognosis by performing peripheral immunological and genetic tests. RESULTS: There were seven boys with age ranging from 4-20 months (median age, 13 months). Four of the seven respiratory infections were caused by Talaromyces marneffei(T. marneffei). Two patients had viral infections caused by cytomegalovirus (CMV) and human adenovirus respectively. One patient had a mixed infection caused by Pneumocystis carinii and CMV. Except for one child who died of respiratory failure, one patient received hematopoietic stem cell transplantation (HSCT) and recovered well, the other five patients survived with regular infusions of intravenous immunoglobulin (IVIg) during the follow-up period. Six patients had reduced antibody levels, especially IgG, IgA, and IgE levels. Increased serum IgM levels were detected in four cases, and three cases presented normal IgM levels at onset. All children were diagnosed with XHIGM with CD40LG variation. Three novel mutations were identified in the present study. CONCLUSIONS: Our study suggests that respiratory infections usually begin within 2 years old, fungi and viruses are important pathogens causing respiratory infections in children with XHIGM. In endemic areas, T. marneffei is the common pathogen of respiratory tract infection in children with the disease.

A Novel De Novo NFKBIA Missense Mutation Associated to Ectodermal Dysplasia with Dysgammaglobulinemia.

Background: Inborn errors of immunity (IEIs) are comprised of heterogeneous groups of genetic disorders affecting immune function. In this report, a 17-month-old Malay patient suspected of having Hyper IgM syndrome, a type of IEIs, was described. However, the diagnosis of Hyper IgM syndrome was excluded by the normal functional studies and the mild features of ectodermal dysplasia observed from a further clinical phenotype inspection. Methods: Whole-exome sequencing (WES) was performed to unravel the causative mutation in this patient. Results: The variant analysis demonstrated a novel missense mutation in NFKBIA (NM_020529:c.94A > T,NP_065390:p.Ser32Cys) and was predicted as damaging by in silico prediction tools. The NFKBIA gene encodes for IκBα, a member of nuclear factor kappa B (NF-κB) inhibitors, playing an important role in regulating NF-κB activity. The mutation occurred at the six degrons (Asp31-Ser36) in IκBα which were evolutionarily conserved across several species. Prediction analysis suggested that the substitution of Ser32Cys may cause a loss of the phosphorylation site at residue 32 and a gain of the sumoylation site at residue 38, resulting in the alteration of post-translational modifications of IκBα required for NF-κB activation. Conclusion: Our analysis hints that the post-translational modification in the NFKBIA Ser32Cys mutant would alter the signaling pathway of NF-κB. Our findings support the usefulness of WES in diagnosing IEIs and suggest the role of post-translational modification of IκBα.

[Clinical effect of allogeneic hematopoietic stem cell transplantation in children with hyper-IgM syndrome]. / å¼‚åŸºå› é€ è¡€å¹²ç»†èƒžç§»æ¤æ²»ç–—å„¿ç«¥é«˜IgM综合征的临床分析.

OBJECTIVES: To evaluate the clinical effect of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in children with hyper-IgM syndrome (HIGM). METHODS: A retrospective analysis was performed on the medical data of 17 children with HIGM who received allo-HSCT. The Kaplan Meier method was used for the survival analysis of the children with HIGM after allo-HSCT. RESULTS: After allo-HSCT, 16 children were diagnosed with sepsis; 14 tested positive for virus within 100 days after allo-HSCT, among whom 11 were positive for Epstein-Barr virus, 7 were positive for cytomegalovirus, and 2 were positive for JC virus; 9 children were found to have invasive fungal disease. There were 6 children with acute graft-versus-host disease and 3 children with chronic graft-versus-host disease. The median follow-up time was about 2 years, and 3 children died in the early stage after allo-HSCT. The children had an overall survival (OS) rate of 82.35%, an event-free survival (EFS) rate of 70.59%, and a disease-free survival (DFS) rate of 76.47%. The univariate analysis showed that the children receiving HLA-matched allo-HSCT had a significantly higher EFS rate than those receiving HLA-mismatched allo-HSCT (P=0.019) and that the children receiving HLA-matched unrelated allo-HSCT had significantly higher OS, EFS, and DFS rates than those receiving HLA-mismatched unrelated allo-HSCT (P<0.05). Compared with the children with fungal infection after allo-HSCT, the children without fungal infection had significantly higher EFS rate (P=0.02) and DFS rate (P=0.04). CONCLUSIONS: Allo-HSCT is an effective treatment method for children with HIGM. HLA-matched allo-HSCT and active prevention and treatment of fungal infection and opportunistic infection may help to improve the prognosis of such children.

Manejo clínico y diagnóstico para pacientes con enfermedades de inmunodeficiencia primaria por déficit de producción de anticuerpos / Clinical management and diagnosis for patients with primary immunodeficiency diseases due to deficiency of antibody production

1. INTRODUCCIÓNLas inmunodeficiencias primarias son un grupo de más de 400 enfermedades, en las cuales el sistema inmune pierde sus funciones de reconocimiento de patógenos o funciona de forma inapropiada. Algunas de ellas son relativamente comunes; mientras otras son raras. Estas enfermedades son en ocasiones de por vida, debilitantes y costosas1,2.Sin embargo, muchos progresos se han hecho desde su des-cripción original en el año de 1952. Se han dado grandes pasos en cuanto a su entendimiento de las Inmunodeficiencias Pri-marias a nivel genético, de sus características, y tratamiento. Algunos tipos afectan un único tipo de célula; otros afectan más de un componente del sistema inmune2,3.Tomando en cuenta que la aproximación es entre 1-2% de la población, a nivel país se puede decir que un aproximado entre 170 000 a 340 000 pacientes en el país no cuentan con un diagnóstico y muchos mueren por falta de este. El número de afiliados al Instituto Ecuatoriano de Seguridad Social hasta julio de 2021 es de 3 672,611 por lo que se considera que un estimado de 36 726 a 73 452 pacientes podrían presentar este tipo de enfermedades y requerir de atención por infecciones a repetición, enfermedad autoinmune y enfermedades linfopro-liferativas, además de que sin un tratamiento específico po-drían fallecer debido a infecciones graves o tener discapacidad permanente, lo que implica mayor carga para el sistema de Seguridad Social en subsidios y menores ingresos. Ecuador, cuenta con 86 pacientes diagnosticados, según la base de datos de la Sociedad Latino-Americana de Inmunodeficiencias4.Algunas terapias, como la de reemplazo para inmunoglobu-linas, a la que es tributaria más del 60% de estas patologías permite que la esperanza de vida y la morbilidad casi alcancen a aquellos que no presentan la enfermedad5­7.

1. INTRODUCTIONPrimary immunodeficiencies are a group of more than 400 diseases, in which the immune system loses its pathogen recog-nition functions or functions inappropriately. Some of them are relatively common, while others are rare. These diseases are sometimes lifelong, debilitating, and costly1,2. However, much progress has been made since its original description in 1952. Great strides have been made in understanding Primary Immunodeficiencies at the genetic level, their characteristics, and treatment. Some types affect only one type of cell; others affect more than one component of the immune system2,3. Considering that the approximation is between 1 to 2% of the population, at the country level we could say that approximately between 170 000 to 340 000 patients in the country do not have a diagnosis and many die due to lack of it. The number of social security affiliates until July 2021 is 3 672,611, so we could consider that approximately 36 726 to 73 452 patients could present this type of disease and require care for recurrent infections, autoimmune disease and lymphoproliferative diseases, in addition to the fact that without specific treatment they could die due to serious infections or have permanent disability, which implies a greater burden for the social security system in subsidies and lower income. Currently the country has 86 diagnosed patients, according to the database of the Latin American Society of Immunodeficiencies4. Many of the therapies, such as immunoglobulin replacement therapy, to which more than 60% of these pathologies are de-pendent, allow life expectancy and morbidity to almost reach those who do not have the disease 5­7.

Variants Disrupting CD40L Transmembrane Domain and Atypical X-Linked Hyper-IgM Syndrome: A Case Report With Leishmaniasis and Review of the Literature.

X-linked hyper-IgM (XHIGM) syndrome is caused by mutations of the CD40LG gene, encoding the CD40L protein. The clinical presentation is characterized by early-onset infections, with profound hypogammaglobulinemia and often elevated IgM, susceptibility to opportunistic infections, such as Pneumocystis jirovecii pneumonia, biliary tract disease due to Cryptosporidium parvum, and malignancy. We report a 41-year-old male presenting with recurrent leishmaniasis, hypogammaglobulinemia, and myopathy. Whole-exome sequencing (WES) identified a missense variant in the CD40LG gene (c.107T>A, p.M36K), involving the transmembrane domain of the protein and a missense variant in the carnitine palmitoyl-transferase II (CPT2; c.593C>G; p.S198C) gene, leading to the diagnosis of hypomorphic XHIGM and CPT2 deficiency stress-induced myopathy. A review of all the previously reported cases of XHIGM with variants in the transmembrane domain showcased that these patients could present with atypical clinical features. Variants in the transmembrane domain of CD40LG act as hypomorphic generating a protein with a lower surface expression. Unlike large deletions or extracellular domain variants, they do not abolish the interaction with CD40, therefore preserving some biological activity.

X-linked hyper IgM syndrome with severe eosinophilia: a case report and review of the literature.

BACKGROUND: Hyper IgM syndromes (HIGMS) are a group of rare primary immunodeficiency disorders. There are limited reports about HIGMS combined with severe eosinophilia. CASE PRESENTATION: In this report, we described a 2-year-old boy with chronic cough and symptoms of hypoxia. Lung computed tomography (CT) scan showed that diffuse ground-glass changes and eosinophils in peripheral blood increased significantly. Subsequent tests revealed a notable decrease in serum IgG and IgA. The lymphocyte subgroup classification was basically normal. Pneumocystis jirovecii were detected from the bronchoalveolar lavage fluid (BALF) of the patient by metagenomic next-generation sequencing (mNGS). After treatments of caspofungin combined with sulfamethoxazole, intravenous immunoglobulin (IVIG) replacement and anti-inflammatory steroid, the clinical symptoms and pulmonary imaging noticeably improved. The absolute eosinophil count (AEC) also returned to normal range. X-linked hyper IgM syndrome was confirmed by gene test. Two months after the diagnosis, the patient underwent allogeneic stem cell transplantation (HSCT) and has recovered well. CONCLUSIONS: Children with HIGMS are prone to opportunistic infections such as Pneumocystis jirovecii pneumonia (PJP). Diffuse interstitial lung disease and hypoglobulinemia in a young child predict the diagnosis of a primary immunodeficiency (PID). mNGS has obvious advantages for obtaining etiological diagnosis of children with PIDs. Severe eosinophilia is rarely reported in this kind of PIDs. Considering literature review and the corresponding reaction to steroid, we proposed that eosinophilia in HIGMS might be related to infections. Steroid therapy can quickly relieve eosinophilia but is easy to rebound if the reduction is too fast. Once the diagnosis of HIGMS is confirmed, the earlier the HSCT, the better the prognosis.

Unusual clinical manifestations and predominant stopgain ATM gene variants in a single centre cohort of ataxia telangiectasia from North India.

Germline ATM gene variations result in phenotypic heterogeneity characterized by a variable degree of disease severity. We retrospectively collected clinical, genetic, and immunological data of 26 cases with A-T. Clinical manifestations included oculocutaneous telangiectasia (100%), ataxia (100%), fever, loose stools or infection (67%), cerebellar atrophy (50%), nystagmus (8%), dysarthria (15.38%), and visual impairment (8%). Genetic analysis confirmed ATM gene variations in 16 unrelated cases. The most common type of variation was stopgain variants (56%). Immunoglobulin profile indicated reduced IgA, IgG, and IgM in 94%, 50%, and 20% cases, respectively. T cell lymphopenia was observed in 80% of cases among those investigated. Unusual presentations included an EBV-associated smooth muscle tumour located in the liver in one case and Hyper IgM syndrome-like presentation in two cases. Increased immunosenescence was observed in T-cell subsets (CD4+CD57+ and CD8+CD57+). T-cell receptor excision circles (TRECs) were reduced in 3/8 (37.50%) cases.

A single-center study points to diverse features and outcome in patients with Hyperimmunoglobulin M Syndrome and Class- Switch Recombination defects.

Isotype class-switch recombination (CSR), somatic hypermutation (SHM), B cell signalling and DNA repair mechanisms defects are responsible for high IgM. The hyperimmunoglobulin M (HIGM) phenotype and CSR-related defects are now classified under primary antibody defects, combined immunodeficiencies or syndromic immunodeficiencies groups. The aim of the study is to evaluate the diverse phenotypic/genotypic/laboratory characteristics and outcome of patients with CSR defects and HIGM-related defects. We enrolled 50 patients. The most common gene defect was Activation-induced cytidine deaminase (AID) deficiency (n = 18), followed by CD40 Ligand (CD40L) (n = 14) and CD40 (n = 3) deficiency. Median ages at first symptom and diagnosis were significantly lower in CD40L deficiency (8.5 and 30 months, respectively) than AID deficiency (30 and 114 months, respectively) (p = .001 and p = .008, respectively). Frequent clinical symptoms were recurrent (66%) and severe (14.9%) infections, and/or autoimmune/non-infectious inflammatory features (48.4%). Eosinophilia and neutropenia were at a higher rate in CD40L deficiency patients (77.8%, p = .002 and 77.8%, p = .002, respectively) when compared to AID deficiency. Median serum IgM level was low in 28.6% of CD40L deficiency patients. It was significantly lower when compared to AID deficiency (p < 0.001). Six patients (CD40L deficiency n = 4, CD40 deficiency n = 2) underwent hematopoietic stem cell transplantation. Five were alive at the last visit. Four patients two patients with CD40L deficiency, one with CD40 deficiency and one with AID deficiency had novel mutations. In conclusion; patients with CSR defects and HIGM phenotype may present with a wide range of clinical manifestations and laboratory findings. Low IgM, neutropenia and eosinophilia were prominent in patients with CD40L deficiency. Characterization of genetic defect-specific clinical and laboratory features may ease the diagnosis, prevent the underdiagnoses of patients and ameliorate the outcome.

Understanding neutropenia secondary to intrinsic or iatrogenic immune dysregulation.

As a key member of the innate and adaptive immune response, neutrophils provide insights into the hematopoietic and inflammatory manifestations of inborn errors of immunity (IEI) and the consequences of immunotherapy. The facile recognition of IEI presenting with neutropenia provides an avenue for hematologists to facilitate early diagnosis and expedite biologically rationale care. Moreover, enhancing the understanding of the molecular mechanisms driving neutropenia in IEI-decreased bone marrow reserves, diminished egress from the bone marrow, and decreased survival-offers an opportunity to further dissect the pathophysiology driving neutropenia secondary to iatrogenic immune dysregulation, eg, immune checkpoint inhibitors and chimeric antigen receptor T-cell therapy.

Pulmonary Radiological Manifestations of Humoral and Combined Immunodeficiencies in a Tertiary Pediatric Center.

Respiratory diseases are considered as significant causes of morbidity and mortality in primary immunodeficiencies. This study aimed to reveal the radiologic patterns of thoracic involvement in these disorders. A total of 58 patients, including 38 cases with combined cellular-humoral and 20 cases with humoral immunodeficiencies, were enrolled in this study. The "combined" group consisted of 12 cases with severe combined immunodeficiency (SCID) and 26 cases with combined immunodeficiency. The "humoral" group included seven patients with Hyper IgM syndrome (HIGMs), seven cases with common variable immunodeficiency (CVID), three patients with X-linked agammaglobulinemia, and three patients with other types of humoral primary immunodeficiencies (PIDs). The mean age of patients at the time of evaluation was 3.3±3.8 and 5.3±3.9 years in combined and humoral groups, respectively. The findings of chest X-rays and CT scans were interpreted and compared. There was a significant difference for alveolar opacification between combined and humoral immunodeficiencies (58% vs. 30%). The bronchopneumonia-like pattern was detected as a significant finding in patients with SCID (42%) and HIGMs (43%). Atrophy of the thymus was detected significantly often in cases of SCID (67%). Two patients with CVID and lipopolysaccharide-responsive and beige-like anchor protein deficiency showed parenchymal changes of granulomatous lymphocytic interstitial lung disease. No significant difference was detected for bronchiectasis, bronchitis/bronchiolitis patterns, pleural effusion, and thoracic lymphadenopathy. Distinct subtypes of primary immunodeficiency may provoke differing and comparable radiological patterns of thoracic involvement; which can clue the clinician and radiologist to the diagnosis of the disease.

[Unrelated umbilical cord blood stem cell transplantation in the treatment of hyper-IgM syndrome caused by CD40 ligand gene mutation: a report of three cases and literature review].

Objective: To evaluate the efficacy and safety of unrelated umbilical cord blood stem cell transplantation (UCBT) with reduced-intensity conditioning regimens in the treatment of hyper-IgM syndrome (HIGM) caused by CD40 ligand gene (CD40LG) mutation. Methods: Clinical features, laboratory data and treatment prognosis of 3 patients with HIGM caused by CD40LG mutation treated with UCBT in Children's Hospital of Fudan University from May 2018 to August 2019 were analyzed retrospectively. The literature search was conducted with "CD40 ligand deficiency" and "hematopoietic stem cell transplantation" as keywords at China National Knowledge Infrastructure, Wanfang, Weipu and Pubmed databases (up to February 2021) to summarize donor selection, stem cell source, conditioning regimen and prognostic factors of this disease. Results: Three boys with recurrent respiratory tract infection were diagnosed as HIGM with CD40LG mutation. The age of UCBT was 1.0, 1.4 and 0.5 years respectively. Reduced-intensity conditioning regimen including busulifan, fludarabine and cyclophosphamide were used in all patients. Human leucocyte antigen matching of patients and umbilical cord blood was 8/10, 10/10 and 9/10 respectively. All patients achieved complete donor chimerism 14 days after UCBT. All patient suffered grade Ⅰ acute skin graft-versus-host disease without other severe complications. Up to the last follow-up, their disease-free survival time were 33, 18, 18 months after transplantation respectively. No reports were found in Chinese journals, while 24 publications were found in English journals. According to the literature, 258 HIGM patients with CD40LG mutation were treated with hematopoietic stem cell transplantation (HSCT). Matched sibling donors (30.6%(79/258)) and unrelated donors (40.3% (104/258)) were main donor types. Bone marrow (50.8%(131/258)) was the main source of grafts, myeloablative conditioning (66.7% (172/258)) was the main conditioning regimen, and the overall survival rate after transplantation was 70.9% (183/258). Lung injury and liver complications before transplantation were adverse factors affecting prognosis. Among the 14 patients who received UCBT, 2 patients suffered from engraftment failure, 2 patients had mixed chimerism and 3 patients died after transplantation. Conclusions: UCBT is safe and effective in the treatment of HIGM caused by CD40LG mutation. Reduced-intensity conditioning regimen is worthy of further study.

Modeling, optimization, and comparable efficacy of T cell and hematopoietic stem cell gene editing for treating hyper-IgM syndrome.

Precise correction of the CD40LG gene in T cells and hematopoietic stem/progenitor cells (HSPC) holds promise for treating X-linked hyper-IgM Syndrome (HIGM1), but its actual therapeutic potential remains elusive. Here, we developed a one-size-fits-all editing strategy for effective T-cell correction, selection, and depletion and investigated the therapeutic potential of T-cell and HSPC therapies in the HIGM1 mouse model. Edited patients' derived CD4 T cells restored physiologically regulated CD40L expression and contact-dependent B-cell helper function. Adoptive transfer of wild-type T cells into conditioned HIGM1 mice rescued antigen-specific IgG responses and protected mice from a disease-relevant pathogen. We then obtained ~ 25% CD40LG editing in long-term repopulating human HSPC. Transplanting such proportion of wild-type HSPC in HIGM1 mice rescued immune functions similarly to T-cell therapy. Overall, our findings suggest that autologous edited T cells can provide immediate and substantial benefits to HIGM1 patients and position T-cell ahead of HSPC gene therapy because of easier translation, lower safety concerns and potentially comparable clinical benefits.