A Review of Chronic Granulomatous Disease

Advancements in Immunology and Microbiology Research: A Comprehensive Exploration of Key Areas

Immunology and microbiology research has witnessed remarkable growth and innovation globally, playing a pivotal role in advancing our understanding of immune mechanisms, disease pathogenesis, and therapeutic interventions. This manuscript presents a comprehensive exploration of the key areas in immunology research, spanning from the utilisation of bacterial proteins as antibody reagents to the intricate realms of clinical immunology and disease management. The utilisation of bacterial immunoglobulin-binding proteins (IBPs), including protein A (SpA), protein G (SpG), and protein L (SpL), has revolutionised serological diagnostics, showing promise in early disease detection and precision medicine. Microbiological studies have shed light on antimicrobial resistance patterns, particularly the emergence of extended-spectrum beta-lactamases (ESBLs), guiding antimicrobial stewardship programmes and informing therapeutic strategies. Clinical immunology research has elucidated the molecular pathways underlying immune-mediated disorders, resulting in tailored management strategies for conditions such as severe combined immunodeficiency (SCID), neuropsychiatric systemic lupus erythematosus (NPSLE), etc. Additionally, significant efforts in vaccine development against tuberculosis and HIV are highlighted, underscoring the ongoing global pursuit of effective preventive measures against these infectious diseases. In summary, immunology and microbiology research have provided significant contributions to global healthcare, fostering collaboration, innovation, and improved patient outcomes.

Diagnosis of Chronic Granulomatous Disease: Strengths and Challenges in the Genomic Era

Chronic granulomatous disease (CGD) is a group of rare primary inborn errors of immunity characterised by a defect in the phagocyte respiratory burst, which leads to severe and life-threatening infective and inflammatory complications. Despite recent advances in our understanding of the genetic and molecular pathophysiology of X-linked and autosomal recessive CGD, and growth in the availability of functional and genetic testing, there remain significant barriers to early and accurate diagnosis. In the current review, we provide an up-to-date summary of CGD pathophysiology, underpinning current methods of diagnostic testing for CGD and closely related disorders. We present an overview of the benefits of early diagnosis and when to suspect and test for CGD. We discuss current and historical methods for functional testing of NADPH oxidase activity, as well as assays for measuring protein expression of NADPH oxidase subunits. Lastly, we focus on genetic and genomic methods employed to diagnose CGD, including gene-targeted panels, comprehensive genomic testing and ancillary methods. Throughout, we highlight general limitations of testing, and caveats specific to interpretation of results in the context of CGD and related disorders, and provide an outlook for newborn screening and the future.

A unified metric of human immune health

Immunological health has been challenging to characterize but could be defined as the absence of immune pathology. While shared features of some immune diseases and the concept of immunologic resilience based on age-independent adaptation to antigenic stimulation have been developed, general metrics of immune health and its utility for assessing clinically healthy individuals remain ill defined. Here we integrated transcriptomics, serum protein, peripheral immune cell frequency and clinical data from 228 patients with 22 monogenic conditions impacting key immunological pathways together with 42 age- and sex-matched healthy controls. Despite the high penetrance of monogenic lesions, differences between individuals in diverse immune parameters tended to dominate over those attributable to disease conditions or medication use. Unsupervised or supervised machine learning independently identified a score that distinguished healthy participants from patients with monogenic diseases, thus suggesting a quantitative immune health metric (IHM). In ten independent datasets, the IHM discriminated healthy from polygenic autoimmune and inflammatory disease states, marked aging in clinically healthy individuals, tracked disease activities and treatment responses in both immunological and nonimmunological diseases, and predicted age-dependent antibody responses to immunizations with different vaccines. This discriminatory power goes beyond that of the classical inflammatory biomarkers C-reactive protein and interleukin-6. Thus, deviations from health in diverse conditions, including aging, have shared systemic immune consequences, and we provide a web platform for calculating the IHM for other datasets, which could empower precision medicine.

A Case of Chronic Granulomatous Disease Masquerading As Tubercular Lymphadenitis in an Infant

Chronic granulomatous disease (CGD) is a rare inborn error of immunity characterized by recurrent fungal and bacterial infections due to defective nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity. This case report describes an 11-month-old female who was initially diagnosed with tubercular lymphadenitis and presented with fever and bilateral neck swelling. Despite receiving anti-tubercular treatment (ATT) and intravenous antibiotics, the patient experienced recurrent infections and abscesses, prompting further investigation. Laboratory tests revealed normal immunoglobulin levels but abnormal nitroblue tetrazolium (NBT) and dihydrorhodamine (DHR) tests, indicating CGD. Genetic analysis (clinical exome by next-generation sequencing) confirmed a novel NCF2 gene mutation associated with autosomal recessive CGD. This patient was treated with prophylactic antibiotics and antifungals and subsequently underwent successful hematopoietic stem cell transplantation (HSCT). This highlights the diagnostic challenges associated with CGD, particularly in tuberculosis-endemic regions such as India, emphasizing the importance of considering primary immunodeficiency disorders in patients with recurrent infections. Early diagnosis and appropriate treatment, including HSCT, can significantly improve patient outcomes. The patient remained infection-free on prophylactic antimicrobials for 1.5 years post-discharge, demonstrating the potential for a favorable prognosis with timely intervention and comprehensive management.

Phagosomal granulocytic ROS in septic patients induce the bacterial SOS response

Septic patients with worst clinical prognosis have increased circulating immature granulocytes (IG), displaying limited phagocytosis and reactive oxygen species (ROS) production. Here, we developed an ex vivo model of incubation of human granulocytes, from septic patients or healthy donors, with Escherichia coli. We showed that the ROS production in Sepsis-IG is lower due to decreased activation and protein expression of the NADPH oxidase complex. We also demonstrated that the low level of ROS production and lower phagocytosis of IG in sepsis induce the bacterial SOS response, leading to the expression of the SOS-regulated quinolone resistance gene qnrB2. Without antimicrobial pressure, the sepsis immune response alone may promote antibiotic resistance expression.

Chronic granulomatous disease: A single-center experience in Central Anatolia

BACKGROUND

Chronic granulomatous disease (CGD), one of the phagocytic cell defects, is the primary immunodeficiency caused by dysfunction of the NADPH oxidase complex in neutrophils.

METHODS

The clinical, demographic and laboratory findings of 17 CGD patients who were followed-up between 2002 and 2021 were obtained retrospectively from the records of the patients.

RESULTS

The number of male and female patients was 10/7. The median age at diagnosis was 5.3 months (range 4-120) for 3 patients with X-CGD, and 42.4 months (range 8-350) for 14 patients with AR-CGD. We have investigated rare CYBA exon 3-6 deletion in 7 patients and hotspot mutation with delGT at the beginning of exon 2 of NCF1 in 5 patients. The most common clinical findings were pneumonia and lymphadenitis with recurrent fever, respectively (41.2%, 35.3%). A total of 154 microbial infections requiring hospital admission (27 in 3 XL and 127 in 14 AR patients) were detected in the follow-up of the patients and median infection number for a patient was 9 in both groups. Eight of 17 patients had stem cell transplantation and the survival rate was 87.5%.

CONCLUSIONS

X-CGD patients are more rapidly recognized by family history and severe infections than those with AR-CGD and early prophylaxis may decrease infectious episodes. We have investigated the large deletion suggesting a possible founder effect for CYBA exon 3-6 deletion in Central Anatolia. Additionally, HSCT transplantation leads to a high survival rate for the patients with CGD.

Infectious complications in the paediatric immunocompromised host: a narrative review

BACKGROUND

Infections are a major cause of morbidity in children with primary or secondary immunodeficiency, and have a negative impact on overall outcome.

OBJECTIVES

This narrative review presents select paediatric-specific aspects regarding the clinical impact, diagnosis, management, and follow-up of infectious complications in patients with primary and secondary immunodeficiencies.

SOURCES

PubMed until January 2024 and searched references in identified articles including the search terms: infection, immunodeficiency or cancer, diagnostics, antimicrobial agents, bacteria or fungus or virus, and follow-up.

CONTENT

Major advances have been made in the early detection and management of patients with primary immunodeficiency, and multiple analyses report in children with cancer on risk groups and periods of risk for infectious complications. Although many diagnostic tools are comparable between children and adults, specific considerations have to be applied, such as minimizing the use of radiation. Antimicrobial drug development remains a major challenge in the paediatric setting, which includes the establishment of appropriate dosing and paediatric approval. Last, long-term follow-up and the impact of late effects are extremely important to be considered in the management of immunocompromised paediatric patients.

IMPLICATIONS

Although infectious disease supportive care of immunocompromised children and adolescents has considerably improved over the last three decades, close international collaboration is needed to target the specific challenges in this special population.

Lack of pulmonary involvement leads to a 3 years delay of diagnosis in a childhood sarcoidosis case with arthritis, ocular symptoms, and bilateral parotid swelling

Key Clinical Message

This paper presents a rare sarcoidosis case in a child of 12 years of age presented with arthritis, bilateral parotid enlargement and ocular, but unfortunately the diagnosis has been missed due to lack of pulmonary involvement.

Abstract

Diagnosis of sarcoidosis is by exclusion, and sometimes, it can be challenging. This paper presents a rare sarcoidosis case in a child of 12 years of age presented with bilateral parotid enlargement. The signs of musculoskeletal and ocular involvement were present before the parotid enlargement, and the parotid swelling persisted for 3 years; but unfortunately the definite diagnosis has been missed by the previous healthcare professionals most probably due to the rarity of the situation, especially lack of pulmonary involvement. Therefore, cooperation between different healthcare specialties is important for an effective diagnosis and management. Despite its rarity, sarcoidosis should always be present in the list of differential diagnosis when encountering multisystem entities like arthritis, ocular symptoms and parotid swelling.

Immune Thrombocytopenic Purpura (ITP) and Chorioretinopathy in Chronic Granulomatous Disease: A Case Report

BACKGROUND

Chronic Granulomatous Disease (CGD) is a rare immunodeficiency disorder characterized by impaired phagocytic function, leading to recurrent infections and granuloma formation. Genetic mutations in NADPH oxidase complex components, such as CYBB, NCF1, NCF2, and CYBA genes, contribute to the pathogenesis. This case report explores the possible ocular and hematologic complications associated with CGD.

CASE PRESENTATION

A 6-year-old girl with a history of vitrectomy, membranotomy, and laser therapy due to congenital blindness (diagnosed with chorioretinopathy) was referred to the hospital with generalized ecchymosis and thrombocytopenia. Diagnostic workup initially suggested chronic immune thrombocytopenic purpura (ITP). Subsequent admissions revealed necrotic wounds, urinary tract infections, and recurrent thrombocytopenia. Suspecting immunodeficiency, tests for CGD, Nitroblue tetrazolium (NBT) and dihydrorhodamine (DHR) were performed. She had a low DHR (6.7), and her NBT test was negative (0.0%). Her whole exome sequencing results confirmed autosomal recessive CGD with a homozygous NCF1 mutation.

CONCLUSION

This case underscores the diverse clinical manifestations of CGD, including recurrent thrombocytopenia and possible early-onset ocular involvement. The diagnostic challenges highlight the importance of a multidisciplinary approach involving hematologists, immunologists, and ophthalmologists for accurate diagnosis and management. The rare coexistence of ITP in CGD emphasizes the intricate link between immunodeficiency and autoimmunity, requiring tailored therapeutic strategies.

Functional neutrophil disorders: Chronic granulomatous disease and beyond

Since their description by Metchnikoff in 1905, phagocytes have been increasingly recognized to be the entities that traffic to sites of infection and inflammation, engulf and kill infecting organisms, and clear out apoptotic debris all the while making antigens available and accessible to the lymphoid organs for future use. Therefore, phagocytes provide the gateway and the first check in host protection and immune response. Disorders in killing and chemotaxis lead not only to infection susceptibility, but also to autoimmunity. We aim to describe chronic granulomatous disease and the leukocyte adhesion deficiencies as well as myeloperoxidase deficiency and G6PD deficiency as paradigms of critical pathways.

Preimplantation genetic testing for X-linked chronic granulomatous disease induced by a CYBB gene variant: A case report

INTRODUCTION

X-linked recessive chronic granulomatous disease (XR-CGD) is a severe primary immunodeficiency principally caused by a CYBB (OMIM: 300481) gene variant. Recurrent fatal bacterial or fungal infections are the main clinical manifestations of XR-CGD.

PATIENT CONCERNS

In the current case, in vitro fertilization (IVF) associated with preimplantation genetic testing for monogenic disorder (PGT-M) was applied for a Chinese couple who had given birth to a boy with XR-CGD.

DIAGNOSIS

Next-generation sequencing-based SNP haplotyping and Sanger-sequencing were used to detect the CYBB gene variant (c.804 + 2T>C, splicing) in this family.

INTERVENTIONS

The patient was treated with IVF and PGT-M successively.

OUTCOMES

In this IVF cycle, 7 embryos were obtained, and 2 of them were euploid and lacked the CYBB gene variant (c.804 + 2T>C). The PGT results were verified by prenatal diagnosis after successful pregnancy, and a healthy girl was eventually born.

CONCLUSION

PGT-M is an effective method for helping families with these fatal and rare inherited diseases to have healthy offspring. It can availably block the transmission of disease-causing loci to descendant.

A rare differential diagnosis of inflammatory bowel disease in a young male patient; a challenging case report

Background

Chronic granulomatous disease (CGD) is a rare disorder normally diagnosed in infancy.

Case presentation

A 27-year-old man admitted with non-specific symptoms of CGD first underwent endoscopy, and colonoscopy procedures as primary evaluation of clinical presentation. Eighteen months after the first admission, he was referred to the emergency department for hematemesis, and critical situations, such as a severe anemic with Hgb= 2.6 mg/dl. As a result of this specific clinical presentation, urgent emergency treatment was performed, and endoscopic examination revealed ulcers and abnormalities in the duodenal bulb and jejunum. Other imaging procedures, such as sonography, and abdominal CT scans, showed splenomegaly. He underwent splenectomy, and after that, endoscopic treatment with balloon TTS dilation was scheduled, but this procedure failed. So, we decided to do a gastro-jujenostomy that alleviated the clinical symptoms. After nine months, he was referred to GOO, and endoscopic evaluation showed giant ulceration with severe stricture in the duodenum, and a polyp in the jejunostomy. Finally, Based on clinical presentation and pathologic evidence of biopsies, the patient approached CGD as the final diagnosis.

Conclusion

Step-by-step, rule out of different highly suspicious diseases may result in a definite CGD diagnosis, and rapid management of these patients may increase the chance of survival.

Case Report: The leopard sign as a potential characteristic of chronic granulomatous disease-associated colitis, unrelated to colitis severity

Background

Chronic granulomatous disease (CGD) is an inborn immune disorder in which the phagocytic system cannot eradicate pathogens, and autoinflammation occurs. Approximately half of the patients have associated gastrointestinal symptoms. Although most cases with CGD-associated colitis present nonspecific histology, colonoscopy in some cases shows brownish dots over a yellowish oedematous mucosa, which is termed a "leopard sign". However, the significance of these signs remains unclear.

Methods

We collected data from patients with CGD whose colonoscopic findings showed the leopard sign.

Results

Three patients with CGD and leopard signs were enrolled in this study. One patient underwent colonoscopy for frequent diarrhoea and weight gain failure, and another for anal fistula. The third patient was without gastrointestinal symptoms and underwent colonoscopy as a screening test before allogeneic haematopoietic cell transplantation (HCT). Endoscopic findings showed a mild leopard sign in the first case; however, non-contiguous and diffuse aphthae were observed throughout the colon. The other two cases were unremarkable except for the leopard sign. All the patients achieved remission with oral prednisolone or HCT. One patient underwent colonoscopy after HCT; results revealed improvements in endoscopy (including the leopard sign) and histological findings. However, another patient underwent colonoscopy after prednisolone treatment; this revealed no change in the leopard sign.

Conclusion

The leopard sign in the colon may be a characteristic endoscopic finding of CGD, even in patients who do not develop severe gastrointestinal symptoms; however, it does not reflect the severity of CGD-associated colitis.

A synthetic notch (synNotch) system linking intratumoral immune-cancer cell communication to a synthetic blood biomarker assay

Introduction: Cellular immunotherapy has greatly improved cancer treatment in recent years. For instance, chimeric antigen receptor (CAR) T cell therapy has been proven highly effective in treating hematological malignancies, and many CAR cell designs are being explored for solid tumors. However, many questions remain why responses differ across patients and some tumor types are resistant. Improved and relatively inexpensive ways to monitor these cells could provide some answers. Clinically, blood tests are regularly used to monitor these therapies, but blood signals often do not reflect the activity of immune cells within the tumor(s). Here, using the synthetic Notch (synNotch) receptor that tethers antigen binding to customized transgene expression, we linked intratumoral immune-cancer cell communication to a simple secreted reporter blood test. Specifically, we engineered immune cells with a CD19-targeted synNotch receptor and demonstrated that binding to CD19 on cancer cells in vivo resulted in the production of secreted embryonic alkaline phosphatase (SEAP) at levels that are readily detected in the blood. Methods and Results: Jurkat T cells were engineered via sequential lentiviral transduction of two components: an anti-CD19 synNotch receptor and a synNotch response element encoding SEAP. Co-culture of engineered cells with CD19+, but not CD19-, Nalm6 cells, resulted in significantly elevated SEAP in media. Nod-scid-gamma (NSG) mice were subcutaneously injected with either CD19+ or CD19- Nalm6 cells. Intratumoral injection of engineered T cells (1x107) resulted in significantly elevated blood SEAP activity in mice bearing CD19+ tumors (n = 7), but not CD19- tumors (n = 5). Discussion: Our synNotch reporter system allows for the monitoring of antigen-dependent intratumoral immune-cancer cell interactions through a simple and convenient blood test. Continued development of this system for different target antigens of interest should provide a broadly applicable platform for improved monitoring of many cell-based immunotherapies during their initial development and clinical translation, ultimately improving our understanding of design considerations and patient-specific responses.

Intestinal microbiome and metabolome signatures in patients with chronic granulomatous disease

BACKGROUND

Chronic granulomatous disease (CGD) is caused by defects in any 1 of the 6 subunits forming the nicotinamide adenine dinucleotide phosphate oxidase complex 2 (NOX2), leading to severely reduced or absent phagocyte-derived reactive oxygen species production. Almost 50% of patients with CGD have inflammatory bowel disease (CGD-IBD). While conventional IBD therapies can treat CGD-IBD, their benefits must be weighed against the risk of infection. Understanding the impact of NOX2 defects on the intestinal microbiota may lead to the identification of novel CGD-IBD treatments.

OBJECTIVE

We sought to identify microbiome and metabolome signatures that can distinguish individuals with CGD and CGD-IBD.

METHODS

We conducted a cross-sectional observational study of 79 patients with CGD, 8 pathogenic variant carriers, and 19 healthy controls followed at the National Institutes of Health Clinical Center. We profiled the intestinal microbiome (amplicon sequencing) and stool metabolome, and validated our findings in a second cohort of 36 patients with CGD recruited through the Primary Immune Deficiency Treatment Consortium.

RESULTS

We identified distinct intestinal microbiome and metabolome profiles in patients with CGD compared to healthy individuals. We observed enrichment for Erysipelatoclostridium spp, Sellimonas spp, and Lachnoclostridium spp in CGD stool samples. Despite differences in bacterial alpha and beta diversity between the 2 cohorts, several taxa correlated significantly between both cohorts. We further demonstrated that patients with CGD-IBD have a distinct microbiome and metabolome profile compared to patients without CGD-IBD.

CONCLUSION

Intestinal microbiome and metabolome signatures distinguished patients with CGD and CGD-IBD, and identified potential biomarkers and therapeutic targets.

Allogeneic HSCT for Symptomatic Female X-linked Chronic Granulomatous Disease Carriers

X-linked chronic granulomatous disease (XL-CGD) is an inherited disorder of superoxide production, causing failure to generate the oxidative burst in phagocytes. It is characterized by invasive bacterial and fungal infections, inflammation, and chronic autoimmune disease. While XL-CGD carriers were previously assumed to be healthy, a range of clinical manifestations with significant morbidity have recently been described in a subgroup of carriers with impaired neutrophil oxidative burst due to skewed lyonization. Allogeneic hematopoietic stem cell transplantation (HSCT) is the standard curative treatment for CGD but has rarely been reported in individual symptomatic carriers to date. We undertook a retrospective international survey of outcome of HSCT for symptomatic XL-CGD carriers. Seven symptomatic female XL-CGD carriers aged 1-56 years underwent HSCT in four centers, indicated for severe and recurrent infection, colitis, and autoimmunity. Two patients died from transplant-related complications, following donor engraftment and restoration of oxidative burst. All surviving patients demonstrated resolution of their neutrophil oxidative burst defect with concordant reduction in infection and inflammatory symptoms and freedom from further immunosuppressive therapy. In conclusion, allogeneic HSCT may cure the phagocyte defect in symptomatic XL-CGD carriers and improve their recurrent and disabling infective and inflammatory symptoms but risks transplant-related complications.

Chronic Granulomatous Disease (CGD): Commonly Associated Pathogens, Diagnosis and Treatment

Chronic granulomatous disease (CGD) is a primary immunodeficiency caused by a defect in the phagocytic function of the innate immune system owing to mutations in genes encoding the five subunits of the nicotinamide adenine dinucleotide phosphatase (NADPH) oxidase enzyme complex. This review aimed to provide a comprehensive approach to the pathogens associated with chronic granulomatous disease (CGD) and its management. Patients with CGD, often children, have recurrent life-threatening infections and may develop infectious or inflammatory complications. The most common microorganisms observed in the patients with CGD are Staphylococcus aureus, Aspergillus spp., Candida spp., Nocardia spp., Burkholderia spp., Serratia spp., and Salmonella spp. Antibacterial prophylaxis with trimethoprim-sulfamethoxazole, antifungal prophylaxis usually with itraconazole, and interferon gamma immunotherapy have been successfully used in reducing infection in CGD. Haematopoietic stem cell transplantation (HCT) have been successfully proven to be the treatment of choice in patients with CGD.

Identifying pathogenic variants related to systemic lupus erythematosus by integrating genomic databases and a bioinformatic approach

Systemic lupus erythematosus (SLE) is an inflammatory-autoimmune disease with a complex multi-organ pathogenesis, and it is known to be associated with significant morbidity and mortality. Various genetic, immunological, endocrine, and environmental factors contribute to SLE. Genomic variants have been identified as potential contributors to SLE susceptibility across multiple continents. However, the specific pathogenic variants that drive SLE remain largely undefined. In this study, we sought to identify these pathogenic variants across various continents using genomic and bioinformatic-based methodologies. We found that the variants rs35677470, rs34536443, rs17849502, and rs13306575 are likely damaging in SLE. Furthermore, these four variants appear to affect the gene expression of NCF2, TYK2, and DNASE1L3 in whole blood tissue. Our findings suggest that these genomic variants warrant further research for validation in functional studies and clinical trials involving SLE patients. We conclude that the integration of genomic and bioinformatic-based databases could enhance our understanding of disease susceptibility, including that of SLE.

The Canadian Society for Immunology's 34th annual meeting 2022: symposia minireview

The Canadian Society for Immunology 2022 Annual Meeting (June 17-20, 2022) brought together immunologists from across the country to discuss current topics and cutting-edge research in immunology. Here we highlight the published work presented during three thematic symposia (1) Immune Development and Layered Immunity; (2) Primary Immune Deficiencies from Thymic Developmental Defects to Dysregulation and Inflammation; and (3) Opposing Inflammatory and Suppressive Regulation of Anti-Tumor Immunity.

A Fatal Case of Chronic Granulomatous Disease in a Young Man

Chronic granulomatous disease (CGD) is a rare X-linked or autosomal recessive disorder of early childhood due to defective nicotinamide adenine dinucleotide phosphate (NADPH) oxidase enzyme in leukocytes. It increases susceptibility to infections by catalase-positive bacteria and fungi. We report a case of an 18-year-old man with CGD who presented to the hospital with septic shock due to bacteremia, pneumonia, and osteomyelitis due to multiple rare microorganisms. Despite aggressive management, he did not survive. Increasing awareness about the common infections in this rare disease, their prevention, and lifelong treatment is warranted.

In Situ Identification of Both IL-4 and IL-10 Cytokine-Receptor Interactions during Tissue Regeneration

Cytokines secreted by individual immune cells regulate tissue regeneration and allow communication between various cell types. Cytokines bind to cognate receptors and trigger the healing process. Determining the orchestration of cytokine interactions with their receptors on their cellular targets is essential to fully understanding the process of inflammation and tissue regeneration. To this end, we have investigated the interactions of Interleukin-4 cytokine (IL-4)/Interleukin-4 cytokine receptor (IL-4R) and Interleukin-10 cytokine (IL-10)/Interleukin-10 cytokine receptor (IL-10R) using in situ Proximity Ligation Assays in a regenerative model of skin, muscle and lung tissues in the mini-pig. The pattern of protein-protein interactions was distinct for the two cytokines. IL-4 bound predominantly to receptors on macrophages and endothelial cells around the blood vessels while the target cells of IL-10 were mainly receptors on muscle cells. Our results show that in situ studies of cytokine-receptor interactions can unravel the fine details of the mechanism of action of cytokines.

Microbiome and Its Dysbiosis in Inborn Errors of Immunity

Inborn errors of immunity (IEI) can present with infections, autoimmunity, lymphoproliferation, granulomas, and malignancy. IEIs are due to genetic abnormalities that disrupt normal host-immune response or immune regulation. The microbiome appears essential for maintaining host immunity, especially in patients with a defective immune system. Altered gut microbiota in patients with IEI can lead to clinical symptoms. Microbial dysbiosis is the consequence of an increase in pro-inflammatory bacteria or a reduction in anti-inflammatory bacteria. However, functional and compositional differences in microbiota are also involved. Dysbiosis and a reduced alpha-diversity are well documented, particularly in conditions like common variable immunodeficiency. Deranged microbiota is also seen in Wiskott–Aldrich syndrome, severe combined immunodeficiency, chronic granulomatous disease, selective immunoglobulin-A deficiency, Hyper IgE syndrome (HIGES), X-linked lymphoproliferative disease-2, immunodysregulation, polyendocrinopathy, enteropathy, x-linked syndrome, and defects of IL10 signalling. Distinct gastrointestinal, respiratory, and cutaneous symptoms linked to dysbiosis are seen in several IEIs, emphasizing the importance of microbiome identification. In this study, we discuss the processes that maintain immunological homeostasis between commensals and the host and the disruptions thereof in patients with IEIs. As the connection between microbiota, host immunity, and infectious illnesses is better understood, microbiota manipulation as a treatment strategy or infection prevention method would be more readily employed. Therefore, optimal prebiotics, probiotics, postbiotics, and fecal microbial transplantation can be promising strategies to restore the microbiota and decrease disease pathology in patients with IEIs.

Graves’ Disease in a Young Patient With Turner’s Syndrome: The Genetic Association

INTRODUCTION

Autoimmune diseases occur more often in females, suggesting a key role for the X chromosome. Curiously, individuals with Turner syndrome (TS), with fewer copies of X-linked genes, are prone to develop autoimmune conditions. Hashimoto's thyroiditis (HT) is described with a relatively high frequency in patients with TS while the association with Graves' disease (GD) is rare. Here we report a rare case of TS with GD in a young patient.

METHOD

A 14-year-old girl presented with hyperthyroid symptoms and eye signs that developed over the past six months. She had somatic stigmata of TS. TS was diagnosed by karyotyping (45,XO/46,XX del Xq22) and GD was diagnosed by a thyroid function test and the presence of autoantibodies. She was treated effectively with carbimazole for GD. Estrogen replacement therapy was also initiated to induce the development of secondary sex characteristics.

CONCLUSION

X chromosome inactivation, an epigenetic process that establishes and maintains dosage compensation of X-linked genes, is especially vulnerable to disruption and may contribute to an autoimmune disease process. The occurrence of autoimmune diseases in patients with TS is discussed with regard to possible abnormalities in X-linked dosage compensation.

Gene Editing in Human Haematopoietic Stem Cells for the Treatment of Primary Immunodeficiencies

In recent years, gene-editing technologies have revolutionised precision medicine, and human trials of this technology have been reported in cell-based cancer therapies and other genetic disorders. The same techniques have the potential to reverse mutations in monogenic primary immunodeficiencies (PIDs), and transplantation of edited haematopoietic stem cells may provide a functional cure for these diseases. In this review, we discuss the methods of gene editing being explored and describe progress made so far with several PIDs. We also detail the remaining challenges, how to confidently detect off-target effects and chromosomal abnormalities in a timely manner, how to obtain long-term benefits, and how to achieve physiological levels of expression of the therapeutic gene. With advances in gene editing, we envisage a robust clinical translation of this technology in the coming decade.

The first successful bone marrow transplantation in Vietnam for a young Vietnamese boy with chronic granulomatous disease: a case report

Background

Chronic granulomatous disease (CGD) is an inborn error of immunity (IEI) disorder that results from defects in the respiratory burst activity in phagocytes, leading to the inability to kill bacterial and fungal microorganisms. CGD patients usually have a high incidence of morbidity such as infections and autoinflammatory diseases and a high mortality rate. Allogeneic bone marrow transplantation (BMT) is the only definitive cure for patients who suffer from CGD.

Case presentation

We report the first transplant case of chronic granulomatous disease in Vietnam. A 25-month-old boy with X-linked CGD underwent bone marrow transplantation from his 5-year-old, full-matched human leukocyte antigen (HLA)-carrier sibling after myeloablative conditioning regimen with busulfan 5.1 mg/kg/day for 4 days, fludarabine 30 mg/m²/day for 5 days, and rATG (Grafalon-Fresenius) 10 mg/kg/day for 4 days. Neutrophil was engrafted on day 13 posttransplant, donor chimerism was 100% on day 30 with the dihydrorhodamine-1,2,3 (DHR 123) flow cytometric assay test that reached 38% of the normal 45 days posttransplant. Five months after transplant, the patient was free of infection with stable DHR 123 assay at 37%, and donor chimerism remained 100%. No sign of a graft-versus-host disease had been observed posttransplant.

Conclusion

We suggest that bone marrow transplantation is a safe and effectual cure for CGD patients, especially for patients with HLA-identical siblings.

Immunosuppression in Patients With Primary Immunodeficiency-Walking the Line

Individuals with primary immunodeficiency (PIDD) experience not only infectious complications but also immune dysregulation leading to autoimmunity, inflammation, and lymphoproliferative manifestations. Management of these complications often requires treatment with additional immunosuppressive medications, which pose an additional risk of infectious complications. Immunosuppression in individuals with PIDD therefore requires careful assessment and consideration of risks and benefits. Medications should be closely monitored, and strategies for risk mitigation of adverse events considered, such as exposure reduction, appropriate vaccination, use of antibiotics/antivirals, and optimization of immunoglobulin replacement therapy. In a subset of individuals who are not tolerating immune modulation or experiencing disease progression despite appropriate interventions, hematopoietic stem-cell transplantation is a management option.

Adult case of chronic granulomatous disease mimicking granulomatosis with polyangiitis

BACKGROUND

This article presents a patient who was initially diagnosed as having granulomatosis with polyangiitis (GPA), and was later diagnosed as having chronic granulomatous disease (CGD) in adulthood. We aimed to raise awareness of CGD, which can be confused with rheumatic diseases.

CASE REPORT

We present a 33-year-old male patient with CGD with recurrent opportunistic bacterial and fungal infections who was diagnosed as having GPA, and had a history of recurrent lung infections and brain abscesses since childhood. The patient, who had cavitary lesions in the lung and mucosal lesions in the nose, was diagnosed as having GPA based on antineutrophil cytoplasmic antibody positivity. CGD was suspected in his last hospitalization after the patient underwent a nitro blue tetrazolium test. Accordingly, neutrophil oxidative function was tested using a dihydrorhodamine assay, which confirmed CGD. Molecular analysis of the patient revealed that the NCF1 gene had a GT deletion at the beginning of exon 2. Our patient was diagnosed as having late-onset CGD; he is currently well and taking antibiotic prophylaxis.

CONCLUSION

As a result of the altered humoral immune response in CGD, there is unregulated inflammation and sustained antigen stimulation. This excessive inflammatory response can be confused with autoimmune diseases and cause delays in diagnosis. This case is important in the differential diagnosis of CGD in adult patients with recurrent opportunistic infections.

Chronic granulomatous disease and McLeod syndrome: Stem cell transplant and transfusion support in a 2-year-old patient—a case report

Chronic granulomatous disease (CGD) with McLeod neuroacanthocytosis syndrome (MLS) is a contiguous gene deletion disorder characterized by defective phagocytic function and decreased Kell antigen expression. CGD cure is achieved through hematopoietic stem cell transplant (HSCT) usually in the peri-pubescent years. The presence of MLS makes peri-transfusion support complex, however. Herein, we present the youngest known case of HSCT for CGD in the setting of MLS. A 2-year-old male patient was diagnosed with CGD plus MLS. Due to the severity of the child’s systemic fungal infection at diagnosis, HSCT was deemed the best treatment option despite his small size and age. A related, matched donor was available, and a unique red blood cell support plan had been implemented. Reduced-intensity conditioning was used to reduce the transplant-related mortality risk associated with myeloablative protocols. The transplant course was uneventful; autologous red blood cell (RBC) transfusion support was successful and allowed for the avoidance of possible antibody formation if allogeneic units had been used. The patient achieved 1-year relapse-free survival. The developed protocols provide a viable path to transplant in the very young, and early transplant to cure could reduce disease-related morbidity.

Hormesis and Oxidative Distress: Pathophysiology of Reactive Oxygen Species and the Open Question of Antioxidant Modulation and Supplementation

Alterations of redox homeostasis leads to a condition of resilience known as hormesis that is due to the activation of redox-sensitive pathways stimulating cell proliferation, growth, differentiation, and angiogenesis. Instead, supraphysiological production of reactive oxygen species (ROS) exceeds antioxidant defence and leads to oxidative distress. This condition induces damage to biomolecules and is responsible or co-responsible for the onset of several chronic pathologies. Thus, a dietary antioxidant supplementation has been proposed in order to prevent aging, cardiovascular and degenerative diseases as well as carcinogenesis. However, this approach has failed to demonstrate efficacy, often leading to harmful side effects, in particular in patients affected by cancer. In this latter case, an approach based on endogenous antioxidant depletion, leading to ROS overproduction, has shown an interesting potential for enhancing susceptibility of patients to anticancer therapies. Therefore, a deep investigation of molecular pathways involved in redox balance is crucial in order to identify new molecular targets useful for the development of more effective therapeutic approaches. The review herein provides an overview of the pathophysiological role of ROS and focuses the attention on positive and negative aspects of antioxidant modulation with the intent to find new insights for a successful clinical application.

Chronic Granulomatous Disease-Like Presentation of a Child with Autosomal Recessive PKCδ Deficiency

BACKGROUND

Autosomal recessive (AR) PKCδ deficiency is a rare inborn error of immunity (IEI) characterized by autoimmunity and susceptibility to bacterial, fungal, and viral infections. PKCδ is involved in the intracellular production of reactive oxidative species (ROS).

MATERIAL AND METHODS

We studied a 5-year old girl presenting with a history of Burkholderia cepacia infection. She had no history of autoimmunity, lymphocyte counts were normal, and no auto-antibodies were detected in her plasma. We performed a targeted panel analysis of 407 immunity-related genes and immunological investigations of the underlying genetic condition in this patient.

RESULTS

Consistent with a history suggestive of chronic granulomatous disease (CGD), oxidative burst impairment was observed in the patient's circulating phagocytes in a dihydrorhodamine 123 (DHR) assay. However, targeted genetic panel analysis identified no candidate variants of known CGD-causing genes. Two heterozygous candidate variants were detected in PRKCD: c.285C > A (p.C95*) and c.376G > T (p.D126Y). The missense variant was also predicted to cause abnormal splicing, as it is located at the splice donor site of exon 5. TOPO-TA cloning confirmed that exon 5 was completely skipped, resulting in a truncated protein. No PKCδ protein was detected in the patient's neutrophils and monocyte-derived macrophages. The monocyte-derived macrophages of the patient produced abnormally low levels of ROS, as shown in an Amplex Red assay.

CONCLUSION

PKCδ deficiency should be considered in young patients with CGD-like clinical manifestations and abnormal DHR assay results, even in the absence of clinical and biological manifestations of autoimmunity.

Comparative Investigation of the Chemiluminescent Properties of a Dibrominated Coelenterazine Analog

Chemi- and bioluminescence are remarkable light-emitting phenomena, in which thermal energy is converted into excitation energy due to a (bio)chemical reaction. Among a wide variety of chemi-/bioluminescent systems, one of the most well-known and studied systems is that of marine imidazopyrazinones, such as Coelenterazine and Cypridina luciferin. Due to the increasing usefulness of their chemi-/bioluminescent reactions in terms of imaging and sensing applications, among others, significant effort has been made over the years by researchers to develop new derivatives with enhanced properties. Herein, we report the synthesis and chemiluminescent characterization of a novel dibrominated Coelenterazine analog. This novel compound consistently showed superior luminescence, in terms of total light output and emission lifetime, to natural imidazopyrazinones and commercially available analogs in aprotic media, while being capable of yellow light emission. Finally, this new compound showed enhanced chemiluminescence in an aqueous solution when triggered by superoxide anion, showing potential to be used as a basis for optimized probes for reactive oxygen species. In conclusion, bromination of the imidazopyrazinone scaffold appears to be a suitable strategy for obtaining Coelenterazines with enhanced properties.

Novel mutations in unrelated Vietnamese patients with chronic granulomatous disease

BACKGROUND

Chronic granulomatous disease (CGD) is a rare primary immunodeficiency disorder (PID) due to genetic defects in the NADPH oxidase of phagocytes. Affected patients become susceptible to infections such as pneumonia, diarrhea, and skin ulcer types. The patients require life-long treatment with prophylactic antibiotics, antifungals, or hematopoietic stem cell transplantation (HSCT) therapy. Early, accurate diagnosis will contribute to the life-prolonging of patients with CGD. This study's aim is to identify the mutation related to the disease. Case presentation Six patients from different Vietnamese families were collected for genetic analysis at Allergy, Immunology, and Rheumatology Department, Vietnam National Hospital Pediatrics. They were diagnosed with CGD by flow cytometry test with the conversion of dihydrorhodamine (DHR) 123 to rhodamine 123.

METHODS

We performed whole exome sequencing (WES) as a tool for detecting novel mutations. The mutations were confirmed by the Sanger sequencing method in patients and their families. The influence of the mutations was predicted with the in silico analysis tools: PROVEAN, SIFT, PolyPhen 2, Mutation Taster, and MaxEntScan.

RESULTS

In this study, five mutations were found in six unrelated patients with CGD from different Vietnamese families. Three novel pathogenic mutations were detected including one mutation (c.45+2T>G) in the CYBB gene and two mutations (c.187_188insA and c.289G>C) in the NCF2 gene.

CONCLUSIONS

Our results of CGD-related mutations contribute to the general understanding of the etiology of the disease and emphasize that WES sequencing can be used as a tool to help to diagnose carriers as well as assist in genetic counseling and prenatal screening.

Development of a Coelenterazine Derivative with Enhanced Superoxide Anion-Triggered Chemiluminescence in Aqueous Solution

Superoxide anion is a reactive oxygen species (ROS) of biological interest. More specifically, it plays a role in intra- and intercellular signaling, besides being associated with conditions such as inflammation and cancer. Given this, efforts have been made by the research community to devise new sensing strategies for this ROS species. Among them, the chemiluminescent reaction of marine Coelenterazine has been employed as a sensitive and dynamic probing approach. Nevertheless, chemiluminescent reactions are typically associated with lower emissions in aqueous solutions. Herein, here we report the synthesis of a new Coelenterazine derivative with the potential for superoxide anion sensing. Namely, this novel compound is capable of chemiluminescence in a dose-dependent manner when triggered by this ROS species. More importantly, the light-emission intensities provided by this derivative were relevantly enhanced (intensities 2.13 × 101 to 1.11 × 104 times higher) in aqueous solutions at different pH conditions when compared to native Coelenterazine. The half-life of the chemiluminescent signal is also greatly increased for the derivative. Thus, a new chemiluminescence molecule with significant potential for superoxide anion sensing was discovered and reported for the first time.

Interpretation of Dihydrorhodamine-1,2,3 Flow Cytometry in Chronic Granulomatous Disease: an Atypical Exemplar

PURPOSE

This is a functional characterization of a novel CYBA variant associated with normal DHR flow cytometry. Chronic granulomatous disease (CGD) is an inborn error of immunity characterized by recurrent bacterial and fungal infections and dysregulated inflammatory responses due to defective phagocytic cell function leading to the formation of granulomas. CGD patients have pathogenic variants in any of the five components of the phagocytic NADPH oxidase, which transfers electrons through the phagosomal membrane and produces superoxide upon bacterial uptake. Here, we report a pediatric female patient with a novel homozygous missense variant (c.293C > T, p.(Ser98Leu)) in CYBA, encoding the p22^phox protein, associated with autosomal recessive CGD.

METHODS AND RESULTS

The patient presented with severe recurrent pneumonia. Specific pathogens identified included Burkholderia and Serratia species suggesting neutrophil functional abnormalities; however, the dihydrorhodamine-1,2,3 (DHR) flow cytometric and cytochrome c reduction assays for neutrophil respiratory burst fell within the low side of the normal range. Western blot and flow cytometric analysis of individual NADPH oxidase components revealed reduced levels of p22^phox and gp91^phoxphox proteins. The pathological consequence of the p.Ser98Leu variant was further evaluated in heterologous expression systems, which confirmed reduced p22^phox protein stability and oxidase activity.

CONCLUSIONS

Although this patient did not exhibit all the classic features of CGD, such as granulomas and skin infections, she had recurrent pneumonias with oxidant-sensitive pathognomonic organisms, resulting in appropriate targeted CGD testing. This case emphasizes the need to contextually interpret laboratory data, especially using clinical findings to direct additional assessments including genetic analysis.

Inborn Errors of Immunity Associated With Type 2 Inflammation in the USIDNET Registry

Background

Monogenic conditions that disrupt proper development and/or function of the immune system are termed inborn errors of immunity (IEIs), also known as primary immunodeficiencies. Patients with IEIs often suffer from other manifestations in addition to infection, and allergic inflammation is an increasingly recognized feature of these conditions.

Methods

We performed a retrospective analysis of IEIs presenting with allergic inflammation as reported in the USIDNET registry. Our inclusion criteria comprised of patients with a reported monogenic cause for IEI where reported lab eosinophil and/or IgE values were available for the patient prior to them receiving potentially curative therapy. Patients were excluded if we were unable to determine the defective gene underlying their IEI. Patients were classified as having eosinophilia or elevated IgE when their record included at least 1 eosinophil count or IgE value that was greater than the age stratified upper limit of normal. We compared the proportion of patients with eosinophilia or elevated IgE with the proportion of samples in a reference population that fall above the upper limit of normal (2.5%).

Results

The query submitted to the USIDNET registry identified 1409 patients meeting inclusion criteria with a monogenic cause for their IEI diagnosis, of which 975 had eosinophil counts and 645 had IgE levels obtained prior to transplantation or gene therapy that were available for analysis. Overall, 18.8% (183/975) of the patients evaluated from the USIDNET registry had eosinophilia and 20.9% (135/645) had an elevated IgE. IEIs caused by defects in 32 genes were found to be significantly associated with eosinophilia and/or an elevated IgE level, spanning 7 of the 10 IEI categories according to the International Union of Immunological Societies classification.

Conclusion

Type 2 inflammation manifesting as eosinophilia or elevated IgE is found in a broad range of IEIs in the USIDNET registry. Our findings suggest that allergic immune dysregulation may be more widespread in IEIs than previously reported.

Neutrophils-From Bone Marrow to First-Line Defense of the Innate Immune System

Neutrophils (polymorphonuclear cells; PMNs) form a first line of defense against pathogens and are therefore an important component of the innate immune response. As a result of poorly controlled activation, however, PMNs can also mediate tissue damage in numerous diseases, often by increasing tissue inflammation and injury. According to current knowledge, PMNs are not only part of the pathogenesis of infectious and autoimmune diseases but also of conditions with disturbed tissue homeostasis such as trauma and shock. Scientific advances in the past two decades have changed the role of neutrophils from that of solely immune defense cells to cells that are responsible for the general integrity of the body, even in the absence of pathogens. To better understand PMN function in the human organism, our review outlines the role of PMNs within the innate immune system. This review provides an overview of the migration of PMNs from the vascular compartment to the target tissue as well as their chemotactic processes and illuminates crucial neutrophil immune properties at the site of the lesion. The review is focused on the formation of chemotactic gradients in interaction with the extracellular matrix (ECM) and the influence of the ECM on PMN function. In addition, our review summarizes current knowledge about the phenomenon of bidirectional and reverse PMN migration, neutrophil microtubules, and the microtubule organizing center in PMN migration. As a conclusive feature, we review and discuss new findings about neutrophil behavior in cancer environment and tumor tissue.

Neutrophil cytosolic factor 2 (NCF2) gene polymorphism is associated with juvenile-onset systemic lupus erythematosus, but probably not with other autoimmune rheumatic diseases in children

BACKGROUND

Genetic variations of neutrophil cytosolic factor 2 (NCF2), a subunit of NADPH oxidase, are usually associated with chronic granulomatous disease, and their relationship with autoimmune disorders through the defective NADPH oxidase function during phagocytosis is suggested. Our study aimed to explore whether there is an association between the non-synonymous single nucleotide polymorphism in the NCF2 gene (rs17849502, NC_000001.11:g.183563445G>T) and the development of juvenile autoimmune rheumatic diseases.

METHODS

In order to test this hypothesis, we conducted a pilot case-control study. In total, 709 children and adolescents, all Belarusians, were involved in the study including patients with juvenile-onset systemic lupus erythematosus (JSLE), juvenile idiopathic arthritis (JIA), Kawasaki disease (KD), and subjects without autoimmune and inflammatory diseases as the clinical control, as well as health newborns as the population control. Real-time polymerase chain reaction was used for genotyping.

RESULTS

The minor T allele of NCF2 occurred most frequently in patients with JSLE (OR = 2.60, 95% CI = 1.18-5.73, p = 0.023 as compared to the clinical control). In groups with JIA and KD, its frequency did not differ from the control. The TT genotype was only observed in 5.7% of patients with JSLE (p = 0.007), but not in other groups.

CONCLUSION

Therefore, our study suggested that NCF2 rs17849502 polymorphism is a potential genetic risk factor for JSLE, while it is probably not for such autoimmune rheumatic diseases as JIA or KD.

The role of neutrophil extracellular traps in acute lung injury

Acute lung injury (ALI) is a heterogeneous inflammatory condition associated with high morbidity and mortality. Neutrophils play a key role in the development of different forms of ALI, and the release of neutrophil extracellular traps (NETs) is emerging as a common pathogenic mechanism. NETs are essential in controlling pathogens, and their defective release or increased degradation leads to a higher risk of infection. However, NETs also contain several pro-inflammatory and cytotoxic molecules than can exacerbate thromboinflammation and lung tissue injury. To reduce NET-mediated lung damage and inflammation, DNase is frequently used in preclinical models of ALI due to its capability of digesting NET DNA scaffold. Moreover, recent advances in neutrophil biology led to the development of selective NET inhibitors, which also appear to reduce ALI in experimental models. Here we provide an overview of the role of NETs in different forms of ALI discussing existing gaps in our knowledge and novel therapeutic approaches to modulate their impact on lung injury.

Hemophagocytic lymphohistiocytosis in a child with chronic granulomatous disease: A rare complication of a rare disorder

Chronic Granulomatous Disease (CGD) is a primary immunodeficiency disorder (PID) of phagocytic cells resulting in failure to eradicate catalase positive microorganisms like Staphylococci and fungal infections; due to deficiency or malfunction of nicotinamide adenine dinucleotide phosphate (NADPH)-oxidase subunits in phagocytic leucocytes. We illustrate here one such case; a six year old girl who was admitted in our hospital with history of prolonged fever, non resolving bilateral otitis media and recurrent pneumonia. She was evaluated for an underlying PID and was found to have CGD based on Nitro blue Tetrazolium (NBT) Slide Test and flow cytometric Dihydrorhodamine (DHR) assay. The child was symptomatic despite initial treatment with first-line followed by second-line antibiotics. During the course of current systemic infection, she also developed infection-associated secondary Hemophagocytic Lympho Histiocytosis (HLH) as suggested by her clinical and laboratory parameters. Despite a thorough search, no microorganism could be isolated and so she was treated with empircal antibiotic therapy comprising of meropenem, linezolid and an antifungal. Fever resolved with gradual improvement of laboratory parameters and finally spontaneous resolution of HLH. We conclude that a high index of suspicion for PID is required in a child with recurrent infections. Identification of underlying infectious agent should be attempted to start targeted antimicrobial therapy; both to prevent as well as cure infection associated secondary HLH.

Stem Cell-Based Disease Models for Inborn Errors of Immunity

The intrinsic capacity of human hematopoietic stem cells (hHSCs) to reconstitute myeloid and lymphoid lineages combined with their self-renewal capacity hold enormous promises for gene therapy as a viable treatment option for a number of immune-mediated diseases, most prominently for inborn errors of immunity (IEI). The current development of such therapies relies on disease models, both in vitro and in vivo, which allow the study of human pathophysiology in great detail. Here, we discuss the current challenges with regards to developmental origin, heterogeneity and the subsequent implications for disease modeling. We review models based on induced pluripotent stem cell technology and those relaying on use of adult hHSCs. We critically review the advantages and limitations of current models for IEI both in vitro and in vivo. We conclude that existing and future stem cell-based models are necessary tools for developing next generation therapies for IEI.

A 31-Year-Old Man With Seizures, Brain Lesion, and Lung Nodules

CASE PRESENTATION

A 31-year-old man was admitted to our hospital with a recent history of generalized seizures. Three months earlier, he started with intermittent hemoptysis. CT scan showed a cavitary lung lesion in the upper segment of the right inferior lobe (RIL). Because of his job as a social worker in a high-risk population, he started treatment for Mycobacterium TB; however, the BAL culture result was negative. At the time of his current admission, he has continued taking rifampicin, isoniazid, pyrazinamide, and levofloxacin. He denied the use of any illicit drugs or alcohol. He had no history of smoking. One year earlier, he visited Southeast Asia, Oceania, and South Africa for several months. He reported a weight loss of 7 kg since then. Except for a recurrent oral candidiasis, he did not have a relevant medical history. His family history was notable for mother with lupus, and brother with sarcoidosis.

Bacillus Calmette-Guérin (BCG) Infections at High Frequency in Both AR-CGD and X-CGD Patients Following BCG Vaccination

BACKGROUND

Patients with chronic granulomatous disease (CGD) develop severe infections, including Bacillus Calmette-Guérin (BCG). Although the autosomal recessive CGD (AR-CGD) patients should hypothetically develop relatively fewer infections compared to the X-linked CGD (X-CGD) patients due to more residual reactive oxygen intermediates, the impacts of BCG vaccination on AR-CGD and X-CGD patients are unclear. Herein, we demonstrated the clinical features of BCG infections, treatments, and genetic factors in CGD patients after BCG vaccination under the Japanese immunization program.

METHODS

We collected data retrospectively from 43 patients with CGD and assessed their history of initial infection, age at diagnosis of CGD, BCG vaccination history, clinical course, treatment for BCG infections, and genetic mutations associated with CGD.

RESULTS

Fourteen CGD patients avoided BCG vaccination because of other preceding infections and family history. Of 29 patients with CGD who received BCG vaccination, 20 patients developed BCG infections. Although the age at onset of initial infection in X-CGD patients was significantly younger than that in AR-CGD patients (P < .01), the onset and frequency of BCG infections were similar in X-CGD and AR-CGD patients. In X-CGD patients, BCG infections equally developed in the patients carrying missense, insertion, deletion, nonsense, and splice mutations of CYBB. All CGD patients with BCG infections were successfully treated with anti-tuberculous drugs.

CONCLUSIONS

Although X-CGD patients develop severe infections at a younger age than AR-CGD patients, our data suggested that BCG infections develop at high frequency in both AR-CGD and X-CGD patients, regardless of genotype and mutant forms.

Recent advances in lentiviral vectors for gene therapy

Lentiviral vectors (LVs), derived from human immunodeficiency virus, are powerful tools for modifying the genes of eukaryotic cells such as hematopoietic stem cells and neural cells. With the extensive and in-depth studies on this gene therapy vehicle over the past two decades, LVs have been widely used in both research and clinical trials. For instance, third-generation and self-inactive LVs have been used to introduce a gene with therapeutic potential into the host genome and achieve targeted delivery into specific tissue. When LVs are employed in leukemia, the transduced T cells recognize and kill the tumor B cells; in β-thalassemia, the transduced CD34⁺ cells express normal β-globin; in adenosine deaminase-deficient severe combined immunodeficiency, the autologous CD34⁺ cells express adenosine deaminase and realize immune reconstitution. Overall, LVs can perform significant roles in the treatment of primary immunodeficiency diseases, hemoglobinopathies, B cell leukemia, and neurodegenerative diseases. In this review, we discuss the recent developments and therapeutic applications of LVs. The safe and efficient LVs show great promise as a tool for human gene therapy.