Successful haploidentical donor hematopoietic stem cell transplant and restoration of STAT3 function in an adolescent with autosomal dominant hyper-IgE syndrome

STAT3 mutation-associated airway epithelial defects in Job syndrome

BACKGROUND

Job syndrome is a disease of autosomal dominant hyper-IgE syndrome (AD-HIES). Patients harboring STAT3 mutation are particularly prone to airway remodeling and airway infections.

OBJECTIVES

Airway epithelial cells play a central role as the first line of defense against pathogenic infection and express high levels of STAT3. This study thus interrogates how AD-HIES STAT3 mutations impact the physiological functions of airway epithelial cells.

METHODS

This study created human airway basal cells expressing 4 common AD-HIES STAT3 mutants (R382W, V463del, V637M, and Y657S). In addition, primary airway epithelial cells were isolated from a patient with Job syndrome who was harboring a STAT3-S560del mutation and from mice harboring a STAT3-V463del mutation. Cell proliferation, differentiation, barrier function, bacterial elimination, and innate immune responses to pathogenic infection were quantitatively analyzed.

RESULTS

STAT3 mutations reduce STAT3 protein phosphorylation, nuclear translocation, transcription activity, and protein stability in airway basal cells. As a consequence, STAT3-mutated airway basal cells give rise to airway epithelial cells with abnormal cellular composition and loss of coordinated mucociliary clearance. Notably, AD-HIES STAT3 airway epithelial cells are defective in bacterial killing and fail to initiate vigorous proinflammatory responses and neutrophil transepithelial migration in response to an experimental model of Pseudomonas aeruginosa infection.

CONCLUSIONS

AD-HIES STAT3 mutations confer numerous abnormalities to airway epithelial cells in cell differentiation and host innate immunity, emphasizing their involvement in the pathogenesis of lung complications in Job syndrome. Therefore, therapies must address the epithelial defects as well as the previously noted immune cell defects to alleviate chronic infections in patients with Job syndrome.

JAKs and STATs from a Clinical Perspective: Loss-of-Function Mutations, Gain-of-Function Mutations, and Their Multidimensional Consequences

The JAK/STAT signaling pathway plays a key role in cytokine signaling and is involved in development, immunity, and tumorigenesis for nearly any cell. At first glance, the JAK/STAT signaling pathway appears to be straightforward. However, on closer examination, the factors influencing the JAK/STAT signaling activity, such as cytokine diversity, receptor profile, overlapping JAK and STAT specificity among non-redundant functions of the JAK/STAT complexes, positive regulators (e.g., cooperating transcription factors), and negative regulators (e.g., SOCS, PIAS, PTP), demonstrate the complexity of the pathway's architecture, which can be quickly disturbed by mutations. The JAK/STAT signaling pathway has been, and still is, subject of basic research and offers an enormous potential for the development of new methods of personalized medicine and thus the translation of basic molecular research into clinical practice beyond the use of JAK inhibitors. Gain-of-function and loss-of-function mutations in the three immunologically particularly relevant signal transducers STAT1, STAT3, and STAT6 as well as JAK1 and JAK3 present themselves through individual phenotypic clinical pictures. The established, traditional paradigm of loss-of-function mutations leading to immunodeficiency and gain-of-function mutation leading to autoimmunity breaks down and a more differentiated picture of disease patterns evolve. This review is intended to provide an overview of these specific syndromes from a clinical perspective and to summarize current findings on pathomechanism, symptoms, immunological features, and therapeutic options of STAT1, STAT3, STAT6, JAK1, and JAK3 loss-of-function and gain-of-function diseases.

Omalizumab for STAT3 Hyper-IgE Syndromes in Adulthood: A Case Report and Literature Review

Background

Hyper-immunoglobulin E (IgE) syndromes (HIES) are a group of primary immune deficiencies disorders (PID) characterized by elevated serum IgE, eczema, recurrent skin, or respiratory system infections and may also be accompanied by some connective tissues and skeletal abnormalities. Currently, there is no complete cure or targeted treatment for HIES. Omalizumab is a humanized recombinant monoclonal antibody against IgE, reducing the level of free IgE, inhibiting the binding of IgE to receptors on the surface of effector cells, and reducing the activation of inflammatory cells and the release of multiple inflammatory mediators. However, the effect of omalizumab in treating HIES remains unknown. Herein, we described a case of an AD-HIES patient with chronic airway disease who benefited from omalizumab treatment.

Case Presentation

A 28-year-old Chinese woman was admitted for recurrent cough for 7 years, markedly elevated serum IgE level, and recurrent pneumonia caused by multiple pathogens, such as Pneumocystis jirovecii, Cytomegalovirus, Staphylococcus aureus, Aspergillus, and Mycobacterium tuberculosis. She had eczema-dermatitis, skin abscess, slightly traumatic fracture since childhood, and developed asthma and allergic bronchopulmonary aspergillosis (ABPA) lately. Using whole-exome sequencing, the STAT3 (c.1294G>T, p.Val432Leu) missense mutation for the autosomal dominant hyper-IgE syndrome was identified, and omalizumab was prescribed at 300 mg every 2 weeks. The patient responded well with the improvement of respiratory symptoms and lung function tests. The level of serum IgE remained stable on follow-up.

Conclusion

Omalizumab treatment proved beneficial in the case of HIES, especially with chronic airway disease, for which therapeutic options are limited. However, larger-scale prospective studies and long-term follow-up are required to establish the efficacy and safety of this therapeutic intervention.

STAT3 Hyper-IgE Syndrome-an Update and Unanswered Questions

The hyper-IgE syndromes (HIES) are a heterogeneous group of inborn errors of immunity sharing manifestations including increased infection susceptibility, eczema, and raised serum IgE. Since the prototypical HIES description 55 years ago, areas of significant progress have included description of key disease-causing genes and differentiation into clinically distinct entities. The first two patients reported had what is now understood to be HIES from dominant-negative mutations in signal transduction and activator of transcription 3 (STAT3-HIES), conferring a broad immune defect across both innate and acquired arms, as well as defects in skeletal, connective tissue, and vascular function, causing a clinical phenotype including eczema, staphylococcal and fungal skin and pulmonary infection, scoliosis and minimal trauma fractures, and vascular tortuosity and aneurysm. Due to the constitutionally expressed nature of STAT3, initial reports at treatment with allogeneic stem cell transplantation were not positive and treatment has hinged on aggressive antimicrobial prophylaxis and treatment to prevent the development of end-organ disease such as pneumatocele. Research into the pathophysiology of STAT3-HIES has driven understanding of the interface of several signaling pathways, including the JAK-STAT pathways, interleukins 6 and 17, and the role of Th17 lymphocytes, and has been expanded by identification of phenocopies such as mutations in IL6ST and ZNF341. In this review we summarize the published literature on STAT3-HIES, present the diverse clinical manifestations of this syndrome with current management strategies, and update on the uncertain role of stem cell transplantation for this disease. We outline key unanswered questions for further study.

Hematopoietic Stem Cell Transplantation Resolves the Immune Deficit Associated with STAT3-Dominant-Negative Hyper-IgE Syndrome

Autosomal dominant hyper-IgE syndrome caused by dominant-negative loss-of-function mutations in signal transducer and activator of transcription factor 3 (STAT3) (STAT3-HIES) is a rare primary immunodeficiency with multisystem pathology. The quality of life in patients with STAT3-HIES is determined by not only the progressive, life-limiting pulmonary disease, but also significant skin disease including recurrent infections and abscesses requiring surgery. Our early report indicated that hematopoietic stem cell transplantation might not be effective in patients with STAT3-HIES, although a few subsequent reports have reported successful outcomes. We update on progress of our patient now with over 18 years of follow-up and report on an additional seven cases, all of whom have survived despite demonstrating significant disease-related pathology prior to transplant. We conclude that effective cure of the immunological aspects of the disease and stabilization of even severe lung involvement may be achieved by allogeneic hematopoietic stem cell transplantation. Recurrent skin infections and abscesses may be abolished. Donor T_H17 cells may produce comparable levels of IL17A to healthy controls. The future challenge will be to determine which patients should best be offered this treatment and at what point in their disease history.

Hematopoietic Stem Cell Transplantation and Vasculopathy Associated With STAT3-Dominant-Negative Hyper-IgE Syndrome

Dominant negative mutations in the transcription-factor STAT3 underlie the rare primary immunodeficiency Job's syndrome. Allogeneic Hematopoietic Stem Cell Transplantation (HSCT) has shown promise in correction of the underlying immunological defect, with one report suggesting HSCT can prevent development of wider connective tissue complications. Here, we report the case of a 26 year old male who developed an acute ST-elevation myocardial infarction due to coronary artery ectasia and thrombosis, occurring despite pediatric allogeneic HSCT for STAT3-HIES and a predicted 10-year conventional cardiovascular risk of 0.1%. Vasculopathy associated with STAT3-HIES may persist or arise following HSCT and can precipitate life-threatening complications. This has implications for counseling and vascular surveillance, and highlights the need for further studies to determine the risk, pathogenesis, and optimal management of the vasculopathy associated with STAT3-HIES.

Autosomal dominant hyper-IgE syndrome: When hematopoietic stem cell transplantation should be considered?

AD-HIES or Job's syndrome is a primary immunodeficiency, caused by dominant negative mutations in signal transducer and activator of transcription (STAT) 3. The syndrome is characterized by infectious, immunologic, and non-immunologic manifestations and is associated with significant morbidity, mortality, and development of lymphomas. What has not yet been elucidated is the role of HSCT in the disease treatment spectrum. We review published cases of patients with AD-HIES that underwent HSCT and attempt to clarify at what stage HSCT should be considered and what are the complications.

Orthognathic Surgical Treatment in a Patient With Hyperimmunoglobulin E Syndrome

Autosomal-dominant hyperimmunoglobulin E syndrome (HIES), or Job syndrome, is a rare, multisystem, primary immunodeficiency disorder. Additionally, patients may also suffer from connective tissue, dental, and bone malformations. While current management of HIES is directed at prophylactic antibiotics to prevent infections, there is limited work describing surgical considerations for these patients, particularly with respect to hardware placement. Here we report a case of a patient with HIES who underwent orthognathic surgery for maxillary advancement and mandibular setback to address his severe class III malocclusion. The patient's postoperative course was complicated by significant infection, requiring multiple operations and ultimately, hardware removal after bone healing. Although this patient ultimately had a good outcome, the role of orthognathic surgery with implant placement in patients with HIES should be approached with caution and careful consideration.

Human diseases caused by impaired signal transducer and activator of transcription and Janus kinase signaling

PURPOSE OF REVIEW

The Janus kinase (JAK) and signal transducer of activation (STAT) pathway plays a key role in the immune system. It is employed by diverse cytokines, interferons, growth factors and related molecules. Mutations in JAK/STAT pathway have been implicated in human disease. Here we review JAK/STAT biology and diseases associated with mutations in this pathway.

RECENT FINDINGS

Over the past 10 years, many mutations in JAK/STAT pathway has been discovered. These disorders have provided insights to human immunology.

SUMMARY

In this review, we summarize the biology of each STAT and JAK as well as discuss the human disease that results from somatic or germline mutations to include typical presentation, immunological parameters and treatment.

Lung disease in STAT3 hyper-IgE syndrome requires intense therapy

BACKGROUND

Pulmonary complications are responsible for high morbidity and mortality rates in patients with the rare immunodeficiency disorder STAT3 hyper-IgE syndrome (STAT3-HIES). The aim of this study was to expand knowledge about lung disease in STAT3-HIES.

METHODS

The course of pulmonary disease, radiological and histopathological interrelations, therapeutic management, and the outcome of 14 STAT3-HIES patients were assessed.

RESULTS

The patients' quality of life was compromised most by pulmonary disease. All 14 patients showed first signs of lung disease at a median onset of 1.5 years of age. Lung function revealed a mixed obstructive-restrictive impairment with reduced FEV1 and FVC in 75% of the patients. The severity of lung function impairment was associated with Aspergillus fumigatus infection and prior lung surgery. Severe lung tissue damage, with reduced numbers of ATP-binding cassette sub-family A member 3 (ABCA3) positive type II pneumocytes, was observed in the histological assessment of two deceased patients. Imaging studies of all patients above 6 years of age showed severe airway and parenchyma destruction. Lung surgeries frequently led to complications, including fistula formation. Long-term antifungal and antibacterial treatment proved to be beneficial, as were inhalation therapy, chest physiotherapy, and exercise. Regular immunoglobulin replacement therapy tended to stabilize lung function.

CONCLUSIONS

Due to its severity, pulmonary disease in STAT3-HIES patients requires strict monitoring and intensive therapy.

A deep intronic splice mutation of STAT3 underlies hyper IgE syndrome by negative dominance

Heterozygous in-frame mutations in coding regions of human STAT3 underlie the only known autosomal dominant form of hyper IgE syndrome (AD HIES). About 5% of familial cases remain unexplained. The mutant proteins are loss-of-function and dominant-negative when tested following overproduction in recipient cells. However, the production of mutant proteins has not been detected and quantified in the cells of heterozygous patients. We report a deep intronic heterozygous STAT3 mutation, c.1282-89C>T, in 7 relatives with AD HIES. This mutation creates a new exon in the STAT3 complementary DNA, which, when overexpressed, generates a mutant STAT3 protein (D427ins17) that is loss-of-function and dominant-negative in terms of tyrosine phosphorylation, DNA binding, and transcriptional activity. In immortalized B cells from these patients, the D427ins17 protein was 2 kDa larger and 4-fold less abundant than wild-type STAT3, on mass spectrometry. The patients' primary B and T lymphocytes responded poorly to STAT3-dependent cytokines. These findings are reminiscent of the impaired responses of leukocytes from other patients with AD HIES due to typical STAT3 coding mutations, providing further evidence for the dominance of the mutant intronic allele. These findings highlight the importance of sequencing STAT3 introns in patients with HIES without candidate variants in coding regions and essential splice sites. They also show that AD HIES-causing STAT3 mutant alleles can be dominant-negative even if the encoded protein is produced in significantly smaller amounts than wild-type STAT3.

Hematopoietic Stem Cell Transplantation in Primary Immunodeficiency Diseases: Current Status and Future Perspectives

Primary immunodeficiencies (PID) are disorders that for the most part result from mutations in genes involved in immune host defense and immunoregulation. These conditions are characterized by various combinations of recurrent infections, autoimmunity, lymphoproliferation, inflammatory manifestations, atopy, and malignancy. Most PID are due to genetic defects that are intrinsic to hematopoietic cells. Therefore, replacement of mutant cells by healthy donor hematopoietic stem cells (HSC) represents a rational therapeutic approach. Full or partial ablation of the recipient's marrow with chemotherapy is often used to allow stable engraftment of donor-derived HSCs, and serotherapy may be added to the conditioning regimen to reduce the risks of graft rejection and graft versus host disease (GVHD). Initially, hematopoietic stem cell transplantation (HSCT) was attempted in patients with severe combined immunodeficiency (SCID) as the only available curative treatment. It was a challenging procedure, associated with elevated rates of morbidity and mortality. Overtime, outcome of HSCT for PID has significantly improved due to availability of high-resolution HLA typing, increased use of alternative donors and new stem cell sources, development of less toxic, reduced-intensity conditioning (RIC) regimens, and cellular engineering techniques for graft manipulation. Early identification of infants affected by SCID, prior to infectious complication, through newborn screening (NBS) programs and prompt genetic diagnosis with Next Generation Sequencing (NGS) techniques, have also ameliorated the outcome of HSCT. In addition, HSCT has been applied to treat a broader range of PID, including disorders of immune dysregulation. Yet, the broad spectrum of clinical and immunological phenotypes associated with PID makes it difficult to define a universal transplant regimen. As such, integration of knowledge between immunologists and transplant specialists is necessary for the development of innovative transplant protocols and to monitor their results during follow-up. Despite the improved outcome observed after HSCT, patients with severe forms of PID still face significant challenges of short and long-term transplant-related complications. To address this issue, novel HSCT strategies are being implemented aiming to improve both survival and long-term quality of life. This article will discuss the current status and latest developments in HSCT for PID, and present data regarding approach and outcome of HSCT in recently described PID, including disorders associated with immune dysregulation.

STAT1 and STAT3 mutations: important lessons for clinical immunologists

INTRODUCTION

The transcription factors signal transducer and activator of transcription (STAT) 1 and STAT3 fulfill fundamental functions in nonimmune and immune cells. The description and follow-up of patients with germline mutations that result in either loss-of-function or gain-of-function have contributed to our understanding of the pathophysiology of these regulators. Depending on the type of mutations, clinical symptoms are complex and can include infection susceptibility, immune dysregulation as well as characteristic nonimmune features. Areas covered: In this review, we provide an overview about mechanistic concepts, clinical manifestations, diagnostic process, and traditional as well as innovative treatment options aiming to help the clinical immunologist to better understand and manage these complex and rare diseases. Clinical and research papers were identified and summarized through PubMed Internet searches, and expert opinions are provided. Expert commentary: The last several years have seen an explosion in the clinical descriptions and pathogenesis knowledge of the diseases caused by GOF and LOF mutations in STAT1 and STAT3. However, harmonization of laboratory testing and follow-up in international cohorts is needed to increase our knowledge about the natural history of these disorders as well as the development of curative or supportive targeted therapies.

TNF overproduction impairs epithelial staphylococcal response in hyper IgE syndrome

Autosomal dominant hyper IgE syndrome (AD-HIES), or Job's syndrome, is a primary immune deficiency caused by dominant-negative mutations in STAT3. Recurrent Staphylococcus aureus skin abscesses are a defining feature of this syndrome. A widely held hypothesis that defects in peripheral Th17 differentiation confer this susceptibility has never been directly evaluated. To assess the cutaneous immune response in AD-HIES, we induced suction blisters in healthy volunteers (HVs) and patients with AD-HIES and then challenged the wound with lethally irradiated bacteria. We show that cutaneous production of IL-17A and IL-17F was normal in patients with AD-HIES. Overproduction of TNF-α differentiated the responses in AD-HIES from HVs. This was associated with reduced IL-10 family signaling in blister-infiltrating cells and defective epithelial cell function. Mouse models of AD-HIES recapitulated these aberrant epithelial responses to S. aureus and involved defective epithelial-to-mesenchymal transition (EMT) rather than a failure of bacterial killing. Defective responses in mouse models of AD-HIES and primary keratinocyte cultures from patients with AD-HIES could be reversed by TNF-α blockade and by drugs with reported modulatory effects on EMT. Our results identify these as potential therapeutic approaches in patients with AD-HIES suffering S. aureus infections.

STAT3-Deficient hyperimmunoglobulin E syndrome: report of a case with orofacial granulomatosis-like disease

Hyperimmunoglobulin E syndrome (HIES) is a rare heterogeneous primary immunodeficiency disorder characterized by infections of the lung and skin, elevated serum immunoglobulin E, and involvement of soft and bony tissues. Autosomal dominant HIES and related disorders are caused by defects in the Janus activated kinase-signal transducer and activator of transcription signaling pathway, leading to reduced numbers of T helper cell type 17 and impaired production of interleukin (IL)-17 A, IL-17 F, and IL-22. In addition, neutrophils have chemotactic defects, resulting in impaired responses at skin and lung sites. We report here a case of orofacial granulomatosis-like disease in a teenage boy ultimately found to have autosomal dominant HIES caused by a heterozygous mutation in the STAT3 gene.

Autosomal Dominant Hyper-IgE Syndrome in the USIDNET Registry

BACKGROUND

Autosomal dominant hyper-IgE syndrome (AD-HIES) is a rare condition.

OBJECTIVE

Data from the USIDNET Registry provide a resource to examine the characteristics of patients with rare immune deficiency diseases.

METHODS

A query was submitted to the USIDNET requesting deidentified data for patients with physician-diagnosed AD-HIES through July 2016.

RESULTS

Data on 85 patients diagnosed with AD-HIES (50 males; 35 females) born between 1950 and 2013, collected by 14 physicians from 25 states and Quebec, were entered into the USIDNET Registry by July 2016. Cumulative follow-up was 2157 years. Of these patients, 45.9% had a family history of HIES. The complications reported included skin abscesses (74.4%), eczema (57.7%), retained primary teeth (41.4%), fractures (39%), scoliosis (34.1%), and cancer (7%). Reported allergic diseases included food (37.8%), environmental (18%), and drugs (42.7%). The mean serum IgE level was 8383.7 kU/mL and was inversely correlated to the patient's age. A total of 49.4% had eosinophilia; 56% were known to be on trimethoprim-sulfamethoxazole, 26.6% on antifungal coverage, and 30.6% on immunoglobulin replacement therapy. Pneumonias were more commonly attributed to Staphylococcus aureus (55.3%) or Aspergillus fumigatus (22.4%); 19.5% had a history of lung abscess; these were most often associated with Pseudomonas aeruginosa (P Fisher's exact test = .029) or A. fumigatus (P Fisher's exact test = .016). Lung abscesses were significantly associated with drug reactions (P χ² = .01; odds ratio: 4.03 [1.2-12.97]), depression (P Fisher's exact test = .036), and lower Karnofsky index scores (P Mann-Whitney = .007).

DISCUSSION

Data from the USIDNET Registry summarize the currently reported clinical characteristics of a large cohort of subjects with AD-HIES.

Loss of stat3 function leads to spine malformation and immune disorder in zebrafish

STAT (Signal Transducers and Activators of Transcription) gene family members have been revealed to be involved in cell growth and differentiation in vertebrates. Despite their physiological importance, their functions are poorly studied at organ and systemic levels. In this study, we performed a genome-wide analysis using data from invertebrates to vertebrates to identify STAT genes and analyze their evolutionary history. Interestingly, the STAT gene family undergoes genome duplications during the evolutionary history with STAT3 homologues firstly appearing in the basal extant vertebrate, sea lamprey, suggesting its possible roles in spine formation. To investigate the functions of stat3 in fish species, TALEN technology was performed to generate mutant zebrafish lines. Stat3 mutant zebrafish showed no obvious defects at early developmental stage but displayed severe lateral and vertical curvature of the spine (scoliosis), spine fracture and the incomplete bone joints with narrower junction between vertebrae at early juvenile stage, as indicated by Alizarin red and Alcian blue staining, radiography and micro-computed tomography (MicroCT) analysis. Transcriptome analysis reveals dramatic alterations in a number of genes involved in immune and infection response, skeletal development and somatic growth, especially downregulated expression of collagen gene family, in the juvenile stat3 mutant zebrafish. Moreover, most of the collagen genes were detected to have abnormal expression pattern during the formation of spine deformities in stat3 mutants. Our data reveal that stat3 is specially expressed in vertebrates and required for normal spine development and immune function in zebrafish.

Protein stabilization improves STAT3 function in autosomal dominant hyper-IgE syndrome

Autosomal dominant hyper-IgE syndrome (AD-HIES) is caused by dominant-negative mutations in STAT3; however, the molecular basis for mutant STAT3 allele dysfunction is unclear and treatment remains supportive. We hypothesized that AD-HIES mutations decrease STAT3 protein stability and that mutant STAT3 activity can be improved by agents that increase chaperone protein activity. We used computer modeling to characterize the effect of STAT3 mutations on protein stability. We measured STAT3 protein half-life (t_1/2) and determined levels of STAT3 phosphorylated on tyrosine (Y) 705 (pY-STAT3) and mRNA levels of STAT3 gene targets in Epstein-Barr virus-transformed B (EBV) cells, human peripheral blood mononuclear cells (PBMCs), and mouse splenocytes incubated without or with chaperone protein modulators-HSF1A, a small-molecule TRiC modulator, or geranylgeranylacetone (GGA), a drug that upregulates heat shock protein (HSP) 70 and HSP90. Computer modeling predicted that 81% of AD-HIES mutations are destabilizing. STAT3 protein t_1/2 in EBV cells from AD-HIES patients with destabilizing STAT3 mutations was markedly reduced. Treatment of EBV cells containing destabilizing STAT3 mutations with either HSF1A or GGA normalized STAT3 t_1/2, increased pY-STAT3 levels, and increased mRNA levels of STAT3 target genes up to 79% of control. In addition, treatment of human PBMCs or mouse splenocytes containing destabilizing STAT3 mutations with either HSF1A or GGA increased levels of cytokine-activated pY-STAT3 within human CD4⁺ and CD8⁺ T cells and numbers of IL-17-producing CD4⁺ mouse splenocytes, respectively. Thus, most AD-HIES STAT3 mutations are destabilizing; agents that modulate chaperone protein function improve STAT3 stability and activity in T cells and may provide a specific treatment.

Hemoptysis in a Patient with Elevated Immunoglobulin E

Recurrent pneumonia with cavitation leading to pneumatoceles, secondary fungal infections, and hemoptysis are major causes of mortality and morbidity in patients with hyper-IgE syndrome. Prevention and aggressive treatment of pneumonia in these patients are essential to prevent further lung damage, but treatment may be delayed because the classic signs/symptoms of infection such as fever, chills, or rigors may be lacking. Early imaging to identify infection is essential for diagnosis and treatment. The mainstay of therapy is continuous, full-dose daily trimethoprim-sulfamethoxazole and commonly fungal coverage. Because hyper-IgE syndrome is a progressive disease, patients' condition may worsen despite compliance with prophylactic therapy.

Hyper-IgE Syndromes and the Lung

Elevated serum IgE has many etiologies including parasitic infection, allergy and asthma, malignancy, and immune dysregulation. The hyper-IgE syndromes caused by mutations in STAT3, DOCK8, and PGM3 are monogenic primary immunodeficiencies associated with high IgE, eczema, and recurrent infections. These primary immunodeficiencies are associated with recurrent pneumonias leading to bronchiectasis; however, each has unique features and genetic diagnosis is essential in guiding therapy, discussing family planning, and defining prognosis. This article discusses the clinical features of these primary immunodeficiencies with a particular focus on the pulmonary manifestations and discussion of the genetics, pathogenesis, and approaches to therapy.

The Ying and Yang of STAT3 in Human Disease

The transcription factor signal transducer and activator of transcription 3 (STAT3) is a critical regulator of multiple, diverse cellular processes. Heterozgyous, germline, loss-of-function mutations in STAT3 lead to the primary immune deficiency Hyper-IgE syndrome. Heterozygous, somatic, gain-of-function mutations in STAT3 have been reported in malignancy. Recently, germline, heterozygous mutations in STAT3 that confer a gain-of-function have been discovered and result in early-onset, multi-organ autoimmunity. This review summarizes what is known about the role of STAT3 in human disease.