Novel Variants of DOCK8 Deficiency in a Case Series of Iranian Patients.

BACKGROUND: Dedicator of Cytokinesis 8 (DOCK8) deficiency, the most frequent cause of autosomal recessive hyper immunoglobulin (Ig)E syndrome, is a rare combined immunodeficiency. OBJECTIVE: In this study, we report seven patients, with consanguineous parents, with five novel variants within the DOCK8 gene. METHODS: For genetic analysis, we performed Whole Exome Sequencing (WES) or targeted sequencing by means of Next-generation sequencing (NGS) for some of the patients. For others, Sanger sequencing, Fluorescence-activated cell sorting (FACS), or polymerase chain reaction (PCR) were used. RESULTS: We report five novel variants within the DOCK8 gene: three deletions (deletion of exons 4-12, 24-30, and 22-27), one frameshift (LRG_196:g.189315dup;p.(Leu1052Profs*7)), and a splice region variant (LRG_196t1:c.741+5G>T). Patients presented with skin lesions, food allergy, candidiasis, otitis, recurrent respiratory infections, short stature, aortic aneurism, gynecomastia, and coarse facial features. Patients had leukocytosis, eosinophilia, lymphopenia, and monocytosis, elevated IgE, IgG, IgA, reduced IgM and IgA levels. Patients had a low percentage of CD3+ and CD4+ cells and a high percentage of CD19+, CD27+CD19+, and recent thymic emigrants T cells. The percentage of natural killer cells was increased in one of the patients while it was decreased in another patient. One patient died due to disseminated intravascular coagulation after hematopoietic stem cell transplantation. CONCLUSION: We reported novel variants within the DOCK8 gene and highlighted the risk of aneurysms in these patients, which have been rarely reported in these patients.

Stat3 loss in mesenchymal progenitors causes Job syndrome-like skeletal defects by reducing Wnt/ß-catenin signaling.

Job syndrome is a rare genetic disorder caused by STAT3 mutations and primarily characterized by immune dysfunction along with comorbid skeleton developmental abnormalities including osteopenia, recurrent fracture of long bones, and scoliosis. So far, there is no definitive cure for the skeletal defects in Job syndrome, and treatments are limited to management of clinical symptoms only. Here, we have investigated the molecular mechanism whereby Stat3 regulates skeletal development and osteoblast differentiation. We showed that removing Stat3 function in the developing limb mesenchyme or osteoprogenitor cells in mice resulted in shortened and bow limbs with multiple fractures in long bones that resembled the skeleton symptoms in the Job Syndrome. However, Stat3 loss did not alter chondrocyte differentiation and hypertrophy in embryonic development, while osteoblast differentiation was severely reduced. Genome-wide transcriptome analyses as well as biochemical and histological studies showed that Stat3 loss resulted in down-regulation of Wnt/ß-catenin signaling. Restoration of Wnt/ß-catenin signaling by injecting BIO, a small molecule inhibitor of GSK3, or crossing with a Lrp5 gain of function (GOF) allele, rescued the bone reduction phenotypes due to Stat3 loss to a great extent. These studies uncover the essential functions of Stat3 in maintaining Wnt/ß-catenin signaling in early mesenchymal or osteoprogenitor cells and provide evidence that bone defects in the Job Syndrome are likely caused by Wnt/ß-catenin signaling reduction due to reduced STAT3 activities in bone development. Enhancing Wnt/ß-catenin signaling could be a therapeutic approach to reduce bone symptoms of Job syndrome patients.

Impaired angiogenesis and extracellular matrix metabolism in autosomal-dominant hyper-IgE syndrome.

There are more than 7000 described rare diseases, most lacking specific treatment. Autosomal-dominant hyper-IgE syndrome (AD-HIES, also known as Job's syndrome) is caused by mutations in STAT3. These patients present with immunodeficiency accompanied by severe nonimmunological features, including skeletal, connective tissue, and vascular abnormalities, poor postinfection lung healing, and subsequent pulmonary failure. No specific therapies are available for these abnormalities. Here, we investigated underlying mechanisms in order to identify therapeutic targets. Histological analysis of skin wounds demonstrated delayed granulation tissue formation and vascularization during skin-wound healing in AD-HIES patients. Global gene expression analysis in AD-HIES patient skin fibroblasts identified deficiencies in a STAT3-controlled transcriptional network regulating extracellular matrix (ECM) remodeling and angiogenesis, with hypoxia-inducible factor 1α (HIF-1α) being a major contributor. Consistent with this, histological analysis of skin wounds and coronary arteries from AD-HIES patients showed decreased HIF-1α expression and revealed abnormal organization of the ECM and altered formation of the coronary vasa vasorum. Disease modeling using cell culture and mouse models of angiogenesis and wound healing confirmed these predicted deficiencies and demonstrated therapeutic benefit of HIF-1α-stabilizing drugs. The study provides mechanistic insights into AD-HIES pathophysiology and suggests potential treatment options for this rare disease.

DOCK8 mutation diagnosed using whole-exome sequencing of the dried blood spot-derived DNA: a case report of an Iraqi girl diagnosed in Japan.

BACKGROUND: Dedicator of cytokinesis 8 (DOCK8) deficiency (MIM #243700) is a rare disease, leads to a combined primary immunodeficiency (PID), and accounts for the autosomal recessive-hyper immunoglobulin E syndrome (AR-HIES). DOCK8 deficiency status characterizes by recurrent infections, atopy, and risk of cancer. Lymphoproliferative disease complicating PID, is difficult to diagnose. Our aim is to present a rare case of PID, and to the best of our knowledge, she is the first case of DOCK8 deficiency from Iraq. The genetic diagnosis was carried out in Japan using dried blood spot-based DNA transfer and whole-exome sequencing. CASE PRESENTATION: An 11-year-old Iraqi girl, of double first-cousin-parents, had a history of severe eczema, food allergy, and repeated infections. She presented with a jaw mass, bilateral cervical and axillary lymphadenopathy, and immunoglobulin (Ig) assays of 20, 3.3 and 1.7-fold above maximum normal level for age of IgE, IgA and IgG, respectively, along with a low IgM, eosinophilia and lymphopenia. Based on the jaw mass biopsy, non-Hodgkin lymphoma was suggested in Iraq, whereas histopathological re-evaluation in Japan revealed the diagnosis of a polyclonal reactive proliferation spectrum of lymphoproliferative disorders/plasmacytic hyperplasia, complicating PID. Whole-exome sequencing supported the diagnosis of PID by identifying a homozygous DOCK8 mutation with previously reported pathogenicity (NM_203447:c.3332delT, p.Phe1113Leufs*2), that may be attributed to consanguinity. CONCLUSIONS: International collaboration using an effective DNA transportation technique and next-generation sequencing was the key to pinpoint the diagnosis of DOCK8 deficiency. Our case asserted that careful pathogenetic evaluation, in an advanced setting, was crucial for ruling out the neoplastic process. Pediatricians in areas with a high prevalence of consanguinity marriage should have a high index of suspicion of DOCK8 deficiency in patients with recalcitrant eczema, and frequent respiratory and skin infectious episodes.

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.

Compound heterozygous TYK2 mutations underlie primary immunodeficiency with T-cell lymphopenia.

Complete tyrosine kinase 2 (TYK2) deficiency has been previously described in patients with primary immunodeficiency diseases. The patients were infected with various pathogens, including mycobacteria and/or viruses, and one of the patients developed hyper-IgE syndrome. A detailed immunological investigation of these patients revealed impaired responses to type I IFN, IL-10, IL-12 and IL-23, which are associated with increased susceptibility to mycobacterial and/or viral infections. Herein, we report a recessive partial TYK2 deficiency in two siblings who presented with T-cell lymphopenia characterized by low naïve CD4+ T-cell counts and who developed Epstein-Barr virus (EBV)-associated B-cell lymphoma. Targeted exome-sequencing of the siblings' genomes demonstrated that both patients carried novel compound heterozygous mutations (c.209_212delGCTT/c.691C > T, p.Cys70Serfs*21/p.Arg231Trp) in the TYK2. The TYK2 protein levels were reduced by 35% in the T cells of the patient. Unlike the response under complete TYK2 deficiency, the patient's T cells responded normally to type I IFN, IL-6, IL-10 and IL-12, whereas the cells displayed an impaired response to IL-23. Furthermore, the level of STAT1 was low in the cells of the patient. These studies reveal a new clinical entity of a primary immunodeficiency with T-cell lymphopenia that is associated with compound heterozygous TYK2 mutations in the patients.

Squamous Cell Carcinoma With Hyper-IgE Syndrome: A Case Report.

BACKGROUND: Hyper-immunoglobulin E syndrome (HIES) is a rare primary immunodeficiency disease characterized by recurrent infections and elevated levels of serum immunoglobulin E, usually over 2000 IU/mL. Recurrent and chronic infection of the epidermis and squamous epithelium may also be a cause of squamous cell carcinoma (SCC). SCC is rare with HIES. CASE REPORT: A 17-year-old male patient who was diagnosed as HIES was admitted with purulent right ear discharge. The patient had a history of eczema starting from the age of 7 months and a history of recurrent middle ear infection starting from the age of 5. Biopsy specimens were taken from the lesion in the external auditory canal, and the lesion was reported as SCC. CONSLUSION: Patients with autosomal recessive HIES are at an increased risk for infections and malignancies. SCC should be considered in the differential diagnosis of the patients presenting with recurrent middle ear infections and immunodeficiency.

Gastrointestinal Manifestations of STAT3-Deficient Hyper-IgE Syndrome.

OBJECTIVE: STAT 3 deficiency (autosomal dominant hyper immunoglobulin E syndrome (AD-HIES)) is a primary immunodeficiency disorder with multi-organ involvement caused by dominant negative signal transducer and activator of transcription gene 3 (STAT3) mutations. We sought to describe the gastrointestinal (GI) manifestations of this disease. METHODS: Seventy subjects aged five to 60 years with a molecular diagnosis of AD-HIES were evaluated at the National Institutes of Health (NIH). Data collection involved a GI symptom questionnaire and retrospective chart review. RESULTS: In our cohort of 70 subjects, we found that 60% had GI symptoms (42/70). The most common manifestations were gastroesophageal reflux disease (GERD) observed in 41%, dysphagia in 31%, and abdominal pain in 24%. The most serious complications were food impaction in 13% and colonic perforation in 6%. Diffuse esophageal wall thickening in 74%, solid stool in the right colon in 50% (12/24), and hiatal hernia in 26% were the most prevalent radiologic findings. Esophagogastroduodenoscopy (EGD) demonstrated esophageal tortuosity in 35% (8/23), esophageal ulceration in 17% (4/23), esophageal strictures requiring dilation in 9% (2/23), and gastric ulceration in 17% (4/23). Esophageal eosinophilic infiltration was an unexpected histologic finding seen in 65% (11/17). CONCLUSION: The majority of AD-HIES subjects develop GI manifestations as part of their disease. Most notable are the symptoms and radiologic findings of GI dysmotility, as well as significant eosinophilic infiltration, concerning for a secondary eosinophilic esophagitis. These findings suggest that the STAT3 pathway may be implicated in a new mechanism for the pathogenesis of several GI disorders.

Progressive multifocal leukoencephalopathy in a patient with lymphoma and presumptive hyper IgE syndrome.

We, herein, report a 23-year-old male with a rare inherited immunodeficiency disease, hyperimmunoglobulin IgE syndrome (HIES), who developed progressive multifocal leukoencephalopathy (PML) and lymphoma simultaneously. Primary immunodeficiency of the patient has remained undiagnosed until adulthood. PML is a severe demyelinating disease of the central nervous system caused by John Cunningham virus. HIES is a rare, inherited immunodeficiency characterized by high serum levels of IgE, recurrent staphylococcal infection, eczema, and hypereosinophilia. PML may accompany primary immunodeficiency syndromes, but the association with HIES is exceedingly rare. We discuss the imaging findings, medical management, and a review of related literature on primary immunodeficiency cases complicating with PML.

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 (t1/2) 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 t1/2 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 t1/2, 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.

Entinostat up-regulates the CAMP gene encoding LL-37 via activation of STAT3 and HIF-1α transcription factors.

Bacterial resistance against classical antibiotics is a growing problem and the development of new antibiotics is limited. Thus, novel alternatives to antibiotics are warranted. Antimicrobial peptides (AMPs) are effector molecules of innate immunity that can be induced by several compounds, including vitamin D and phenyl-butyrate (PBA). Utilizing a luciferase based assay, we recently discovered that the histone deacetylase inhibitor Entinostat is a potent inducer of the CAMP gene encoding the human cathelicidin LL-37. Here we investigate a mechanism for the induction and also find that Entinostat up-regulates human ß-defensin 1. Analysis of the CAMP promoter sequence revealed binding sites for the transcription factors STAT3 and HIF-1α. By using short hairpin RNA and selective inhibitors, we found that both transcription factors are involved in Entinostat-induced expression of LL-37. However, only HIF-1α was found to be recruited to the CAMP promoter, suggesting that Entinostat activates STAT3, which promotes transcription of CAMP by increasing the expression of HIF-1α. Finally, we provide in vivo relevance to our findings by showing that Entinostat-elicited LL-37 expression was impaired in macrophages from a patient with a STAT3-mutation. Combined, our findings support a role for STAT3 and HIF-1α in the regulation of LL-37 expression.

[Severe atopic dermatitis caused by rare immunodeficiency in childhood]. / Sjælden immundefekt bag svær atopisk dermatitis i barnealderen.

Two children are presented with autosomal recessive hyper IgE syndrome caused by a mutation in the dedicator of cytokinesis 8 gene (DOCK8). The manifestations are typically severe atopic dermatitis, food allergies, elevated serum IgE concentration, viral skin infections and risk of malignancies. DOCK8 deficiency was first reported in 2009, following the death of the oldest sibling. The youngest sibling was cured after allogenic stem cell transplantation. This case report illustrates the need of awareness of primary immunodeficiency in children with atypical manifestation of atopic dermatitis in combination with recurrent infections.

Hyper-IgE syndromes: recent advances in pathogenesis, diagnostics and clinical care.

PURPOSE OF REVIEW: This review provides an overview on recent data regarding pathogenesis, diagnostics and clinical care of hyper-IgE syndromes (HIES). HIES are a group of primary immunodeficiencies with overlapping and distinct features, most frequently caused by deficiency in signal transducer and activator of transcription 3 (STAT3) or dedicator of cytokinesis 8 (DOCK8). RECENT FINDINGS: Particular progress has been made in deciphering the relevance of STAT3 and DOCK8 for B-cell, T-cell and natural killer-cell immunity as well as in understanding allergic features. Multisystemic features of STAT3-deficient HIES, for example, recurrent fractures and osteopenia, a high degree of vasculopathy and brain white matter hyperintensities, have been thoroughly characterized. IgG replacement may add to the clinical care in STAT3-deficient HIES. In DOCK8-deficient HIES, the high morbidity and deaths in early age seem to justify allogeneic hematopoietic stem cell transplantation. New HIES entities have also been reported. SUMMARY: The recent advances expand our understanding of HIES, and improve the diagnostics and clinical care. Yet, more research is required to fully elucidate the specific infection susceptibilities and lung complications, particularly in STAT3-deficient HIES. Future studies also need to focus on clinical care and treatment of nonimmunologic features of HIES, as well as on exploring curative treatments.

Síndrome de hiperinmunoglobulinemia E: revisión de la casuística con énfasis en las manifestaciones orofaciales / Hyperimmunoglobulinemia E syndrome: a review of the literature with emphasis on orofacial manifestations

El síndrome de Hiper EgE (SHIE) es una rara inmunodeficiencia caracterizada por abscesos cutáneos, neumonías recurrentes, conformación de neumatoceles y elevados niveles de IgE en suero. Se ha reconocido la asociación de rasgos faciales, esqueléticos y dentales, pero su frecuencia es poco conocida. Objetivo: describir la epidemiología, presentación clínica, hallazgos de laboratorio y tratamiento de este síndrome desde el punto de vista médico y odontológico, con énfasis en las manifestaciones estomatológicas y dentales. Métodos. Métodos: realizamos una revisión científica sistemática de todos los reporte y series de casos de SHIE en las bases de datos Lilacs, Medline, SciELO y Biblioteca Cochrane, utilizando como descriptores DeCS/MeSH las palabras claves: hyper IgE AND immunodeficiency, hypereosinophilia, Job´s syndrome, hiperinmunoglobulinemia E. Resultados: revisamos 31 publicaciones con 328 pacientes. Los abscesos cutáneos se encontraron en 89 pior ciento de los casos, la neumonía en el 87 por ciento y la IgE sérica dio una mediana de 3.417 Ul/mL. Los rasgos faciales característicos estuvieron en el 69 por ciento, las alteraciones dentarias en 58 por ciento y la candidiasis oral fue reportada en 53 por ciento de los pacientes. Conclusión: el síndrome de IgE es un desorden multisistémico que afecta a la dentición, el esqueleto, el tejido conectivo y el sistema inmune. Por esto, el odontopediatra debe ser capaz de reconocer el fenotipo orofacial para mejorar la calidad del diagnóstico y brindar el abordaje terapéutico apropiado...

Novel STAT3 mutation causing hyper-IgE syndrome: studies of the clinical course and immunopathology.

PURPOSE: Reporting a clinical case with a novel mutation in the signal transducer and activator of transcription 3 (STAT3) gene resulting in autosomal dominant hyper-immunoglobulin E syndrome (AD-HIES). Here we also had the opportunity to perform in-depth immunologic investigations to further understand the immunopathology of this primary immunodeficiency. METHODS: The patient, a baby boy, was clinically assessed according to the scoring system developed by Grimbacher et al. and STAT3 was investigated by DNA sequencing. Immunologic work-up consisted of lymphocyte phenotyping and proliferation assays, measurement of soluble mediators and routine investigations. RESULTS: According to the Grimbacher score the patient was likely to have AD-HIES and a novel heterozygous STAT3 mutation (c.1110-3C>A), causing a splice error, was identified. Lymphocyte phenotyping revealed decreased numbers of interleukin (IL)-17 producing T-helper lymphocytes and aberrant B-lymphocyte subsets. Proliferative in vitro lymphocyte responses against C. albicans, staphylococcal enterotoxins and pokeweed mitogen were supernormal at presentation, whereas only the elevated response to pokeweed mitogen persisted. The soluble mediators IL-5, -10, -12, -13, -15 and granulocyte colony stimulatory factor were elevated in serum. CONCLUSION: A novel heterozygous STAT3 mutation causing defective splicing of exon 12 was identified. Lymphocyte phenotyping revealed deranged subpopulations. Despite the clinical picture with severe C. albicans and staphylococcal infections, the patient's lymphocytes mounted responses to these pathogens. The hypereosinophilia and high immunoglobulin E levels might partly be explained by elevated IL-5 and -13 as a result of lack of negative feedback from defective STAT3 signaling.