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Purpose: Wiskott-Aldrich syndrome (WAS) is an X-linked genetic disorder characterized by distinctive features including microthrombocytopenia, eczema and recurrent infections. In the present study we report clinical, immunological and molecular spectrum of 41 WAS patients diagnosed over last five years. Methods: Clinical and family history was collected from case records. Comprehensive immunological assessments including lymphocyte subset analysis, and flow cytometry based evaluation of WAS protein (WASP) expressions were performed in patients along with evaluation of carrier status in mothers. Genetic analysis was carried out with either Sanger sequencing or targeted exome sequencing. Results: The patients included in this study presented at a median age of 9.5 months, with two adult cases. Clinical manifestations encompassed thrombocytopenia, eczema, bleeding, diarrhea, respiratory tract infections, CMV infection, and malignancy. Immunological phenotype revealed T cell lymphopenia, B cell lymphopenia, and elevated IgE levels. Flow cytometry analysis of WASP was performed in 36 cases out of which 68.42% demonstrated complete absent expression while others showed reduced expression. Genetic analysis highlighted that the majority of mutations affect the WH1 domain of WASP while both adult patients showed intronic mutations. Molecular Dynamics analysis conducted for the novel variants P398R and G33R showed an average RMSD (Å) higher than that of the wild type, indicating greater structural perturbations in WASP. Conclusion: In the present study we have documented 56.09% novel WAS mutations in Indian cohort. Notably, the application of flow cytometry has emerged as a valuable and efficient diagnostic tool for identifying these WAS patients. [ABSTRACT FROM AUTHOR]

Background and aims: Wiskott-Aldrich syndrome (WAS) is an X-linked recessive primary immunodeficiency disorder characterized by severe eczema, recurrent infections, and micro-thrombocytopenia. Allogeneic hematopoietic stem cell transplantation (HSCT) is a potentially curative therapeutic option for patients with classic form. The risk of developing post-transplant tumors appears to be higher in patients with WAS than in other inborn errors of immunity (IEIs), but the actual incidence is not well defined, due to the scarcity of published data. Methods: Herein, we describe a 10-year-old patient diagnosed with WAS, treated with HSCT in the first year of life, who subsequently developed two rare solid tumors, kaposiform hemangioendothelioma and desmoid tumor. A review of the literature on post-HSCT tumors in WAS patients has been performed. Results: The patient received diagnosis of classic WAS at the age of 2 months (Zhu score = 3), confirmed by WAS gene sequencing, which detected the nonsense hemizygous c.37C>T (Arg13X) mutation. At 9 months, patient underwent HSCT from a matched unrelated donor with an adequate immune reconstitution, characterized by normal lymphocyte subpopulations and mitogen proliferation tests. Platelet count significantly increased, even though platelet count never reached reference values. A mixed chimerism was also detected, with a residual WASP-population on monocytes (27.3%). The patient developed a kaposiform hemangioendothelioma at the age of 5. A second abdominal tumor was identified, histologically classified as a desmoid tumor when he reached the age of 10 years. Both hematopoietic and solid tumors were identified in long-term WAS survivors after HSCT. Conclusion: Here, we describe the case of a patient with WAS who developed two rare solid tumors after HSCT. An active surveillance program for the risk of tumors is necessary in the long-term follow-up of post-HSCT WAS patients. [ABSTRACT FROM AUTHOR]

BackgroundWe undertook a study to determine the impact of Wiskott Aldrich Syndrome (WAS) and X-linked thrombocytopenia (XLT) and their therapies upon the health-related quality of life (HRQOL) of patients and their families.Materials and methodsWe undertook a survey of patients and their families, who self-identified as having either WAS or XLT. We assessed the PedsQL™ 4.0, the parent proxy form, and the family impact module. These results were compared with normative data from previously published reports.ResultsSixty-eight patients (29 patients completed both the PedsQL™ 4.0 and the parent proxy form; 21 completed only the PedsQL™ 4.0; and 18 completed only the parent proxy form) were included. In contrast to patient-reported outcomes, parents of patients who had a bone marrow transplant (BMT) reported that their children had better QOL scores compared with those who did not (82.6 vs. 73.3, p = 0.023). The QOL of patients vs. previously published normative data showed decreases in patient scores for psychosocial health (72.62 vs. 86.58, p =

Background and aimsWiskott–Aldrich syndrome (WAS) is an X-linked recessive primary immunodeficiency disorder characterized by severe eczema, recurrent infections, and micro-thrombocytopenia. Allogeneic hematopoietic stem cell transplantation (HSCT) is a potentially curative therapeutic option for patients with classic form. The risk of developing post-transplant tumors appears to be higher in patients with WAS than in other inborn errors of immunity (IEIs), but the actual incidence is not well defined, due to the scarcity of published data.MethodsHerein, we describe a 10-year-old patient diagnosed with WAS, treated with HSCT in the first year of life, who subsequently developed two rare solid tumors, kaposiform hemangioendothelioma and desmoid tumor. A review of the literature on post-HSCT tumors in WAS patients has been performed.ResultsThe patient received diagnosis of classic WAS at the age of 2 months (Zhu score = 3), confirmed by WAS gene sequencing, which detected the nonsense hemizygous c.37C>T (Arg13X) mutation. At 9 months, patient underwent HSCT from a matched unrelated donor with an adequate immune reconstitution, characterized by normal lymphocyte subpopulations and mitogen proliferation tests. Platelet count significantly increased, even though platelet count never reached reference values. A mixed chimerism was also detected, with a residual WASP− population on monocytes (27.3%). The patient developed a kaposiform hemangioendothelioma at the age of 5. A second abdominal tumor was identified, histologically classified as a desmoid tumor when he reached the age of 10 years. Both hematopoietic and solid tumors were identified in long-term WAS survivors after HSCT.ConclusionHere, we describe the case of a patient with WAS who developed two rare solid tumors after HSCT. An active surveillance program for the risk of tumors is necessary in the long-term follow-up of post-HSCT WAS patients.

The Wiskott--Aldrich syndrome (WAS) is an X-linked primary immune deficiency caused by a mutation in the WAS gene. This leads to altered or absent WAS protein (WASp) expression and function resulting in thrombocytopenia, eczema, recurrent infections, and autoimmunity. In T cells, WASp is required for immune synapse formation. Patients with WAS show reduced numbers of peripheral blood T lymphocytes and an altered T-cell receptor repertoire. In vitro, their peripheral T cells show decreased proliferation and cytokine production upon aCD3/aCD28 stimulation. It is unclear whether these T-cell defects are acquired during peripheral activation or are, in part, generated during thymic development. Here, we assessed the role of WASp during T-cell differentiation using artificial thymic organoid cultures and in the thymus of humanized mice. Although CRISPR/Cas9 WAS knockout hematopoietic stem and progenitor cells (HSPCs) rearranged the T-cell receptor and differentiated to T-cell receptor (TCR)+ CD4+ CD8+ double-positive (DP) cells similar to wild-type HSPCs, a partial defect in the generation of CD8 single-positive (SP) cells was observed, suggesting that WASp is involved in their positive selection. TCR repertoire analysis of the DP and CD8+ SP population, however, showed a polyclonal repertoire with no bias toward autoreactivity. To our knowledge, this is the first study of the role of WASp in human T-cell differentiation and on TCR repertoire generation. [ABSTRACT FROM AUTHOR]

The Wiskott–Aldrich syndrome (WAS) is an X-linked primary immune deficiency caused by a mutation in the WAS gene. This leads to altered or absent WAS protein (WASp) expression and function resulting in thrombocytopenia, eczema, recurrent infections, and autoimmunity. In T cells, WASp is required for immune synapse formation. Patients with WAS show reduced numbers of peripheral blood T lymphocytes and an altered T-cell receptor repertoire. In vitro, their peripheral T cells show decreased proliferation and cytokine production upon aCD3/aCD28 stimulation. It is unclear whether these T-cell defects are acquired during peripheral activation or are, in part, generated during thymic development. Here, we assessed the role of WASp during T-cell differentiation using artificial thymic organoid cultures and in the thymus of humanized mice. Although CRISPR/Cas9 WAS knockout hematopoietic stem and progenitor cells (HSPCs) rearranged the T-cell receptor and differentiated to T-cell receptor (TCR)+ CD4+ CD8+ double-positive (DP) cells similar to wild-type HSPCs, a partial defect in the generation of CD8 single-positive (SP) cells was observed, suggesting that WASp is involved in their positive selection. TCR repertoire analysis of the DP and CD8+ SP population, however, showed a polyclonal repertoire with no bias toward autoreactivity. To our knowledge, this is the first study of the role of WASp in human T-cell differentiation and on TCR repertoire generation.

Wiskott Aldrich Syndrome is an X-linked primary immunodeficiency disorder characterized by microthrombocytopenia, severe immunodeficiency, and eczema. To define clinical-laboratory features, genetic defects (known/novel) of 23 patients of Wiskott Aldrich Syndrome/X-linked Thrombocytopenia (WAS/XLT) cohort, establish relationships between molecular defects and clinical features if present, evaluate patients who underwent hematopoietic stem cell transplantation (HSCT) and did not. Qualitative analysis from patients' hospital files and Sanger sequencing for molecular diagnosis was performed. Twenty-two WAS patients and one XLT patient were included in the study. The median age of diagnosis was 15 months (2.5–172 months). The most common symptom was otitis media and all patients had microthrombocytopenia. Autoimmune findings were detected in 34.7% (8 patients) of the patients; three patients (13%) had positive anti-nuclear antibody (ANA), three patients (13%) hemolytic anemia, one patient autoimmune neutropenia, two patients vasculitis, and one patient demyelinating polyneuropathy. Nine of the 23 (39,1%) patients had HSCT with nearly 90% success. We identified 13 different mutations in our cohort; seven were novel. HSCT is the only curative treatment for WAS. The study confirms that early diagnosis is very important for the success of therapy, so we must increase awareness in society and physicians to keep an eye out for clues. Our study cohort and follow-up period are not sufficient to establish phenotype-genotype correlation, so a larger cohort from various centers with longer follow-up will be more decisive. [ABSTRACT FROM AUTHOR]

Introduction. Wiskott-Aldrich syndrome is a rare X-linked disorder characterized by microthrombocytopenia, eczema, and recurrent infections. It is caused by mutations of the WAS gene which encodes the WAS protein (WASp) – a key regulator of actin polymerization in hematopoietic cells. Mutations within the WASp gene result in a wide heterogeneity of clinical disease, ranging from ‘classical WAS’ to mild asymptomatic thrombocytopenia (X-linked thrombocytopenia [XLT]), or congenital neutropenia (X-lined neutropenia [XLN]). Case presentation. This present paper reports a phenotypical and laboratory description of two children diagnosed with WAS and one child diagnosed with XLT. The first case was a six months old male with septicemia, thrombocytopenia, eczema and petechial rash. The second case was a 2 years old boy presenting with complaints of recurrent infections, eczema and thrombocytopenia with small platelet size. The third case was a 16 years old boy who presented with thrombocytopenia and recurrent sinopulmonary infections. Conclusions. Due to a wide spectrum of clinical findings, the diagnosis of WAS/XLT should be considered in any male patient presenting with petechiae, bruises, and congenital or early-onset thrombocytopenia associated with small platelet size.

The actin cytoskeletal regulator Wiskott Aldrich syndrome protein (WASp) has been implicated in maintenance of the autophagy-inflammasome axis in innate murine immune cells. Here, we show that WASp deficiency is associated with impaired rapamycin-induced autophagosome formation and trafficking to lysosomes in primary human monocyte-derived macrophages (MDMs). WASp reconstitution in vitro and in WAS patients following clinical gene therapy restores autophagic flux and is dependent on the actin-related protein complex ARP2/3. Induction of mitochondrial damage with CCCP, as a model of selective autophagy, also reveals a novel ARP2/3-dependent role for WASp in formation of sequestrating actin cages and maintenance of mitochondrial network integrity. Furthermore, mitochondrial respiration is suppressed in WAS patient MDMs and unable to achieve normal maximal activity when stressed, indicating profound intrinsic metabolic dysfunction. Taken together, we provide evidence of new and important roles of human WASp in autophagic processes and immunometabolic regulation, which may mechanistically contribute to the complex WAS immunophenotype.

BACKGROUND: Wiskott Aldrich syndrome is a primary immunodeficiency notable for eczema, recurrent infections, bleeding diathesis and microcytic thrombocytopenia. CASE: A 4½ year old boy presented with recurrent sinopulmonary infections, repeated treatment for severe eczema since infancy, thrombocytopenia with low platelet volume. His brother and uncles died during childhood due to repeated illnesses. We outline ways to diagnose and manage children in resource limited settings. CONCLUSION: Wiskott Aldrich syndrome can be diagnosed by its clinical triad of syndromes. Mutation of the WASP gene confirms diagnosis. Increasing reports of primary immune deficiencies in Ethiopia call for improved education and care for clinical immunology. [ABSTRACT FROM AUTHOR]

The field of primary immunodeficiencies has pioneered many of the advances in haematopoietic stem cell transplantation and cellular therapies over the last 50 years. The first patients to demonstrate sustained benefit and prolonged cure from the primary genetic defect following allogeneic haematopoietic stem cell transplantation were patients with primary immunodeficiencies. Although primary immunodeficiency patients began the modern era of haematopoietic stem cell transplantation, the history is nevertheless short-in answer to the question “what is the long term outcome of patients transplanted for primary immunodeficiencies?” we often have to say that we do not know. We believe that most patients who undergo haematopoietic stem cell transplantation for primary immunodeficiencies should live a normal lifespan with a fully corrected immune system. We are now beginning to understanding long term outcomes, the relationship to the underlying genetic defect, age, and pre-morbid condition of the patient at time of transplantation, stem cell source and donor, and effect of pre-transplant cytoreductive chemotherapy conditioning. The long term consequences of post-transplant complications such as graft vs. host disease, veno-occlusive disease, or immune dysregulation are also being recognized. Additionally, some genetic defects have a systemic distribution, and we are learning the natural history of these defects once the immunodeficiency has been removed.

Summary: Wiskott Aldrich syndrome (WAS) is a primary immunodeficiency disease resulting in recurrent infections, eczema and microthrombocytopaenia. In its classical form, significant combined immune deficiency, autoimmune complications and risk of haematological malignancy necessitate early correction with stem cell transplantation or gene therapy. A milder form, X‐linked thrombocytopaenia (XLT), shares similar bleeding risk from thrombocytopaenia but is not associated with other significant clinical features and is generally managed conservatively. Here, we detail our approach to the diagnosis and treatment of classical WAS and XLT. [ABSTRACT FROM AUTHOR]

The Wiskott-Aldrich syndrome protein (WASP) participates in innate and adaptive immunity through regulation of actin cytoskeleton-dependent cellular processes, including immune synapse formation, cell signaling, migration and cytokine release. There is also emerging evidence for a direct role in nuclear transcription programmes uncoupled from actin polymerization. A deeper understanding of some of the more complex features of Wiskott Aldrich syndrome (WAS) itself, such as the associated autoimmunity and inflammation, has come from identification of defects in the number and function of anti-inflammatory myeloid cells and regulatory T and B cells, as well as defects in positive and negative B-cell selection. In this review we outline the cellular defects that have been characterized in both human WAS patients and murine models of the disease. We will emphasize in particular recent discoveries that provide a mechanistic insight into disease pathology, including lymphoid and myeloid cell homeostasis, immune synapse assembly and immune cell signaling. [ABSTRACT FROM AUTHOR]

The Wiskott Aldrich Syndrome (WAS) is a well defined X-linked recessive disorder associated with microplatelet thrombocytopeniae, eczema, secondary pyogenic infections, and an increased risk of autoimmunity and lymphoreticular neoplasia. The responsible mutations that are associated with WAS and X-linked thrombocytopeniae are mutations in the WAS protein. Severity of the disease varies with types of WASP mutations. Hematopoietic stem cell transplantations or gene therapy is the only curative therapy for WAS patients. Improved profilactic antimicrobial therapy againts secondary infections and prophylactic use of IVIG have markedly prolonged the life expectancy of WAS patients. (Journal of Current Pediatrics 2008; 6: 119-23)

Wiskott–Aldrich syndrome is a life-threatening primary immunodeficiency associated with a bleeding tendency, eczema and a high incidence of autoimmunity and malignancy. Stem cell transplantation offers the opportunity of cure for all these complications, and over the past 35 years there has been a remarkable improvement in survival following this treatment. Here, we review advances in management of clinical complications pre- and post-transplant, as well as discuss the morbidity Wiskott–Aldrich syndrome patients experience following treatment. For patients with a poorly matched stem cell donor, recent gene therapy trials demonstrate encouraging results and the potential of low-toxicity therapy for all patients. [ABSTRACT FROM AUTHOR]

Aldrich syndrome (WAS) is an X-linked primary immunodeficiency, associated with WASP gene mutation that causes severe immunological abnormalities and alterations in platelet function. A seven year old male patient with WASP, began with acute abdominal pain, fever and knee swelling. The diagnosis of septic arthritis was made, and he was treated with broad-spectrum antibiotics and human gammaglobulin. During treatment he presented digestive tract bleeding with hypovolemic shock; after 72 hours palpable purpura in upper and lower extremities appeared. Then Henoch-Schönlein purpura with abdominal vasculitis was suspected, and later confirmed by histopathology. Methylprednisolone pulses were initiated, showing improvement within 24 hours. The patient had a severe inflammatory reaction, caused by a serious infectious disease, but the clinical evolution suggested an autoimmune disease such as Henoch-Schönlein purpura. Up to 20% of patients with WAS have autoimmune manifestations of vasculitis. An early diagnosis of autoimmunity in WAS is important for a favorable clinical outcome. [ABSTRACT FROM AUTHOR]

Wiskott Aldrich syndrome is an X-linked recessive disorder characterized by thrombocytopenia with microplatelets, eczema, recurrent infections, and predisposition to autoimmune disease and malignancy. It is a rare syndrome, and the incidence rate is approximately 4 in every 1 million live male births with no clear ethnic or racial predilection. The purpose of this paper was to report a case of Wiskott Aldrich syndrome with oral involvement demonstrated by 2 male siblings. [ABSTRACT FROM AUTHOR]

The author discusses how can the Pimary Immune Deficiency Treatment Consortium (PIDTC), a National Institutes of Health (NIH)-sponsored rare disease consortium, improved the Pimary Immune Deficiency (PID) therapy. The topics he discussed includes PIDTC protocols, the issue for rare PID disorders, and severe combined immunodeficiency (SCID).

The Wiskott Aldrich Syndrome (WAS) is a well defined X-linked recessive disorder associated with microplatelet thrombocytopeniae, eczema, secondary pyogenic infections, and an increased risk of autoimmunity and lymphoreticular neoplasia. The responsible mutations that are associated with WAS and X-linked thrombocytopeniae are mutations in the WAS protein. Severity of the disease varies with types of WASP mutations. Hematopoietic stem cell transplantations or gene therapy is the only curative therapy for WAS patients. Improved profilactic antimicrobial therapy againts secondary infections and prophylactic use of IVIG have markedly prolonged the life expectancy of WAS patients. [ABSTRACT FROM AUTHOR]

A 15 years old male with a primary diagnosis of Wiskott Aldrich syndrome presented a laryngeal B cell lymphoma associated with Epstein–Barr virus. A chemotherapy and a radiotherapy were started in association with an endoscopic debulking of the tumor. The child died of respiratory failure secondary to a lung infection. The incidence of NHL (non-Hodgkin''s lymphoma) of laryngeal origin in infants is extremely low and to our knowledge it has never been found in Wiskott Aldrich syndrome. [Copyright &y& Elsevier]

Focuses on the Immunoglobulin E (IgE) abnormalities in primary immunodeficiency disorders (PID) in which either deficiency or excess of IgE production is associated with increased susceptibility to infection. Factors for the IgE levels in childhood; Disorders characterized by defective and excessive IgE production; Recurrence of hyperimmunoglobulin E infection syndrome.

We report a one and half year old male child diagnosed with Wiskott - Aldrich syndrome (WAS). He had persistent thrombocytopenia which on bone marrow biopsy was found to be macrothrombocytopenia. He did not exhibit any characteristic clinical and laboratory findings indicating the syndrome. A test for WASp gene was done which showed reduced expression. Thus it is essential to test for mutations of the WAS gene in all unexplained cases of infantile thrombocytopenia even in the absence of characteristic feature of microthrombocytopenia. [ABSTRACT FROM AUTHOR]

Wiskott-Aldrich Syndrome (WAS) family proteins are Arp2/3 activators that mediate the branched-actin network formation required for cytoskeletal remodeling, intracellular transport and cell locomotion. Wasp and Scar/WAVE, the two founding members of the family, are regulated by the GTPases Cdc42 and Rac, respectively. By contrast, linear actin nucleators, such as Spire and formins, are regulated by the GTPase Rho. We recently identified a third WAS family member, called Wash, with Arp2/3-mediated actin nucleation activity. We show that Drosophila Wash interacts genetically with Arp2/3, and also functions downstream of Rho1 with Spire and the formin Cappuccino to control actin and microtubule dynamics during Drosophila oogenesis. Wash bundles and crosslinks F-actin and microtubules, is regulated by Rho1, Spire and Arp2/3, and is essential for actin cytoskeleton organization in the egg chamber. Our results establish Wash and Rho as regulators of both linear- and branched-actin networks, and suggest an Arp2/3-mediated mechanism for how cells might coordinately regulate these structures. [ABSTRACT FROM AUTHOR]