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1.
Nat Immunol ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609546

RESUMO

The linear ubiquitin assembly complex (LUBAC) consists of HOIP, HOIL-1 and SHARPIN and is essential for proper immune responses. Individuals with HOIP and HOIL-1 deficiencies present with severe immunodeficiency, autoinflammation and glycogen storage disease. In mice, the loss of Sharpin leads to severe dermatitis due to excessive keratinocyte cell death. Here, we report two individuals with SHARPIN deficiency who manifest autoinflammatory symptoms but unexpectedly no dermatological problems. Fibroblasts and B cells from these individuals showed attenuated canonical NF-κB responses and a propensity for cell death mediated by TNF superfamily members. Both SHARPIN-deficient and HOIP-deficient individuals showed a substantial reduction of secondary lymphoid germinal center B cell development. Treatment of one SHARPIN-deficient individual with anti-TNF therapies led to complete clinical and transcriptomic resolution of autoinflammation. These findings underscore the critical function of the LUBAC as a gatekeeper for cell death-mediated immune dysregulation in humans.

2.
Nature ; 623(7988): 803-813, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37938781

RESUMO

Patients with autoimmune polyendocrinopathy syndrome type 1 (APS-1) caused by autosomal recessive AIRE deficiency produce autoantibodies that neutralize type I interferons (IFNs)1,2, conferring a predisposition to life-threatening COVID-19 pneumonia3. Here we report that patients with autosomal recessive NIK or RELB deficiency, or a specific type of autosomal-dominant NF-κB2 deficiency, also have neutralizing autoantibodies against type I IFNs and are at higher risk of getting life-threatening COVID-19 pneumonia. In patients with autosomal-dominant NF-κB2 deficiency, these autoantibodies are found only in individuals who are heterozygous for variants associated with both transcription (p52 activity) loss of function (LOF) due to impaired p100 processing to generate p52, and regulatory (IκBδ activity) gain of function (GOF) due to the accumulation of unprocessed p100, therefore increasing the inhibitory activity of IκBδ (hereafter, p52LOF/IκBδGOF). By contrast, neutralizing autoantibodies against type I IFNs are not found in individuals who are heterozygous for NFKB2 variants causing haploinsufficiency of p100 and p52 (hereafter, p52LOF/IκBδLOF) or gain-of-function of p52 (hereafter, p52GOF/IκBδLOF). In contrast to patients with APS-1, patients with disorders of NIK, RELB or NF-κB2 have very few tissue-specific autoantibodies. However, their thymuses have an abnormal structure, with few AIRE-expressing medullary thymic epithelial cells. Human inborn errors of the alternative NF-κB pathway impair the development of AIRE-expressing medullary thymic epithelial cells, thereby underlying the production of autoantibodies against type I IFNs and predisposition to viral diseases.


Assuntos
Autoanticorpos , Predisposição Genética para Doença , Interferon Tipo I , NF-kappa B , Humanos , Autoanticorpos/imunologia , COVID-19/genética , COVID-19/imunologia , Mutação com Ganho de Função , Heterozigoto , Proteínas I-kappa B/deficiência , Proteínas I-kappa B/genética , Interferon Tipo I/antagonistas & inibidores , Interferon Tipo I/imunologia , Mutação com Perda de Função , NF-kappa B/deficiência , NF-kappa B/genética , Subunidade p52 de NF-kappa B/deficiência , Subunidade p52 de NF-kappa B/genética , Pneumonia Viral/genética , Pneumonia Viral/imunologia , Timo/anormalidades , Timo/imunologia , Timo/patologia , Células Epiteliais da Tireoide/metabolismo , Células Epiteliais da Tireoide/patologia
3.
Am J Clin Exp Immunol ; 12(5): 98-106, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38022870

RESUMO

OBJECTIVES: Asthma is the most prevalent respiratory disease, caused by chronic bronchial inflammation. Cytokines are known to play an important role in the pathophysiology of asthma. This study aimed to compare interleukin-4 (IL-4) and interleukin-10 (IL-10) gene polymorphisms between Iranian pediatric asthmatic patients and healthy controls and to investigate IL4 and IL10 gene variations in children with atopic and non-atopic asthma phenotypes. METHODS: In this prospective case-control study, a total of 95 unrelated pediatric asthmatic patients were recruited according to the Global Initiative for Asthma (GINA) criteria. The control group comprised two subgroups of 538 and 491 healthy individuals, undergoing IL4 and IL10 polymorphism assessments, respectively. The IL4 -589C/T (rs2243250) and IL10 -592A/C (rs1800872) gene polymorphisms were evaluated using the tetra-primer amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) assay. RESULTS: The findings indicated a significant difference in IL4 gene polymorphisms at position -589 between the asthmatic and healthy control groups. However, no significant difference was found in terms of IL10 gene polymorphisms, and they were not associated with atopy in the patients. CONCLUSION: The IL4 -589C/T polymorphism (rs2243250) can be a risk factor for asthma susceptibility, whereas the IL10 -592A/C polymorphism (rs1800872) is not a risk factor in the Iranian pediatric population. The results also showed that these polymorphisms are not risk factors for atopy in asthmatic children.

4.
Cell ; 186(23): 5114-5134.e27, 2023 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-37875108

RESUMO

Human inherited disorders of interferon-gamma (IFN-γ) immunity underlie severe mycobacterial diseases. We report X-linked recessive MCTS1 deficiency in men with mycobacterial disease from kindreds of different ancestries (from China, Finland, Iran, and Saudi Arabia). Complete deficiency of this translation re-initiation factor impairs the translation of a subset of proteins, including the kinase JAK2 in all cell types tested, including T lymphocytes and phagocytes. JAK2 expression is sufficiently low to impair cellular responses to interleukin-23 (IL-23) and partially IL-12, but not other JAK2-dependent cytokines. Defective responses to IL-23 preferentially impair the production of IFN-γ by innate-like adaptive mucosal-associated invariant T cells (MAIT) and γδ T lymphocytes upon mycobacterial challenge. Surprisingly, the lack of MCTS1-dependent translation re-initiation and ribosome recycling seems to be otherwise physiologically redundant in these patients. These findings suggest that X-linked recessive human MCTS1 deficiency underlies isolated mycobacterial disease by impairing JAK2 translation in innate-like adaptive T lymphocytes, thereby impairing the IL-23-dependent induction of IFN-γ.


Assuntos
Interferon gama , Janus Quinase 2 , Infecções por Mycobacterium , Humanos , Masculino , Proteínas de Ciclo Celular/metabolismo , Interferon gama/imunologia , Interleucina-12 , Interleucina-23 , Janus Quinase 2/metabolismo , Mycobacterium/fisiologia , Infecções por Mycobacterium/imunologia , Infecções por Mycobacterium/metabolismo , Proteínas Oncogênicas/metabolismo
5.
Iran J Allergy Asthma Immunol ; 22(4): 337-344, 2023 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-37767676

RESUMO

Asthma is one of the most prevalent chronic lung diseases that afflict genetically predisposed individuals. Certain cytokine gene polymorphisms have been associated with asthma. Tumor necrosis factor-alpha (TNF-α) is a potent inflammatory cytokine that can modulate nonspecific inflammation to influence asthma. This study aimed to define the relationship between the TNF gene polymorphism at position -308 and asthma susceptibility, as well as atopic and non-atopic asthma. Using polymerase chain reaction with sequence-specific primers, we investigated genotype frequencies and alleles of a polymorphic gene coding for TNF-α in 86 pediatric patients with asthma and 470 healthy controls of the same race. Seventy-four patients underwent a skin prick test. The homozygous AA variant (-308, rs1800629) was the most common genotype among patients, accounting for 63.3% of all cases. In contrast, homozygous GG (-308) was significantly less prevalent in the patient group compared to the control group. TNF A (-308) allele frequency was 85.5% among asthma patients and 16.6% among healthy controls. The genotype and allele frequencies of TNF (-308 A>G, rs1800629) did not differ between atopic and non-atopic asthma. In conclusion, TNF (-308) AA and AG genotypes are associated with asthma susceptibility in Iranian children, although there was no significant difference in polymorphism between atopic and non-atopic asthma and no difference in asthma severity groups.

6.
J Clin Immunol ; 43(8): 1941-1952, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37584719

RESUMO

PURPOSE: Major histocompatibility complex class II (MHC-II) deficiency is a rare inborn error of immunity (IEI). Impaired antigen presentation to CD4 + T cells results in combined immunodeficiency (CID). Patients typically present with severe respiratory and gastrointestinal tract infections at early ages. Hematopoietic stem cell transplantation (HSCT) is the only curative therapy. METHODS: We describe the clinical, immunologic, and genetic features of eighteen unrelated Iranian patients with MHC-II deficiency. RESULTS: Consanguinity was present in all affected families. The median age at the initial presentation was 5.5 months (range 7 days to 18 years). The main symptoms included failure to thrive, persistent diarrhea, and pneumonia. Autoimmune and neurologic features were also documented in about one-third of the patients, respectively. Thirteen patients carried RFXANK gene mutations, two carried RFX5 gene mutations, and three carried a RFXAP gene mutation. Six patients shared the same RFXANK founder mutation (c.162delG); limited to the Iranian population and dated to approximately 1296 years ago. Four of the patients underwent HSCT; three of them are alive. On the other hand, nine of the fourteen patients who did not undergo HSCT had a poor prognosis and died. CONCLUSION: MHC-II deficiency is not rare in Iran, with a high rate of consanguinity. It should be considered in the differential diagnosis of CID at any age. With the limited access to HSCT and its variable results in MHC-II deficiency, implementing genetic counseling and family planning for the affected families are mandatory. We are better determined to study the c.162delG RFXANK heterozygous mutation frequency in the Iranian population.


Assuntos
Proteínas de Ligação a DNA , Imunodeficiência Combinada Severa , Fatores de Transcrição , Humanos , Recém-Nascido , Proteínas de Ligação a DNA/genética , Antígenos de Histocompatibilidade Classe II/genética , Irã (Geográfico) , Mutação/genética , Imunodeficiência Combinada Severa/genética , Fatores de Transcrição/genética
7.
Pediatr Allergy Immunol ; 34(7): e13990, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37492921

RESUMO

BACKGROUND: In order to support the comprehensive classification of Leukocyte Adhesion Deficiency-I (LAD-I) severity by simultaneous screening of CD11a/CD18, this study assessed clinical, laboratory, and genetic findings along with outcomes of 69 LAD-I patients during the last 15 years. METHODS: Sixty-nine patients (40 females and 29 males) with a clinical phenotype suspected of LAD-I were referred to Immunology, Asthma, and Allergy research institute, Tehran, Iran between 2007 and 2022 for further advanced immunological screening and genetic evaluations as well as treatment, were enrolled in this study. RESULTS: The diagnosis median age of the patients was 6 months. Delayed umbilical cord separation was found in 25 patients (36.2%). The median diagnostic delay time was 4 months (min-max: 0-82 months). Forty-six patients (66.7%) were categorized as severe (CD18 and/or CD11a: below 2%); while 23 children (33.3%) were in moderate category (CD18 and/or CD11a: 2%-30%). During the follow-ups, 55.1% of children were alive with a mortality rate of 44.9%. Skin ulcers (75.4%), omphalitis (65.2%), and gingivitis (37.7%) were the most frequent complaints. Genetic analysis of the patients revealed 14 previously reported and three novel pathogenic mutations in the ITGB2 gene. The overall survival of patients with and without hematopoietic stem cell transplantation was 79.3% and 55.6%, respectively. CONCLUSION: Physicians' awareness of LAD-I considering delayed separation of umbilical cord marked neutrophilic leukocytosis, and variability in CD11 and CD18 expression levels, and genetic analysis leads to early diagnosis and defining disease severity. Moreover, the prenatal diagnosis would benefit families with a history of LAD-I.


Assuntos
Antígenos CD18 , Síndrome da Aderência Leucocítica Deficitária , Masculino , Gravidez , Feminino , Humanos , Antígenos CD18/genética , Síndrome da Aderência Leucocítica Deficitária/diagnóstico , Síndrome da Aderência Leucocítica Deficitária/genética , Diagnóstico Tardio , Irã (Geográfico) , Leucócitos/metabolismo
8.
Pediatr Rheumatol Online J ; 21(1): 55, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37312195

RESUMO

BACKGROUND: Deficiency of adenosine deaminase 2 (DADA2) is an autosomal recessive autoinflammatory disease caused by mutations in the ADA2 gene. DADA2 has a broad spectrum of clinical presentations. Apart from systemic manifestations, we can categorize most of the signs and symptoms of DADA2 into the three groups of vasculitis, hematologic abnormalities, and immunologic dysregulations. The most dominant vasculitis features are skin manifestations, mostly in the form of livedo racemosa/reticularis, and early onset ischemic or hemorrhagic strokes. Hypogammaglobulinemia that is found in many cases of DADA2 brings immunodeficiencies into the differential diagnosis. Cytopenia, pure red cell aplasia (PRCA), and bone marrow failure (BMF) are the hematologic abnormalities commonly found in DADA. CASE PRESENTATION: We introduce eleven patients with DADA2 diagnosis, including two brothers and sisters, one set of twin sisters, and one father and his daughter and son. Ten patients (91%) had consanguineous parents. All the patients manifested livedo racemose/reticularis. Ten patients (91%) reported febrile episodes, and seven (64%) had experienced strokes. Only one patient had hypertension. Two of the patients (11%) presented decreased immunoglobulin levels. One of the patients presented with PRCA. Except for the PRCA patient with G321E mutation, all of our patients delivered G47R mutation, the most common mutation in DADA2 patients. Except for one patient who unfortunately passed away before the diagnosis was made and proper treatment was initiated, the other patients' symptoms are currently controlled; two of the patients presented with mild symptoms and are now being treated with colchicine, and the eight others responded well to anti-TNFs. The PRCA patient still suffers from hematologic abnormalities and is a candidate for a bone marrow transplant. CONCLUSIONS: Considering the manifestations and the differential diagnoses, DADA2 is not merely a rheumatologic disease, and introducing this disease to hematologists, neurologists, and immunologists is mandatory to initiate prompt and proper treatment. The efficacy of anti-TNFs in resolving the symptoms of DADA2 patients have been proven, but not for those with hematologic manifestations. Similarly, they were effective in controlling the symptoms of our cohort of patients, except for the one patient with cytopenia.


Assuntos
Adenosina Desaminase , Peptídeos e Proteínas de Sinalização Intercelular , Masculino , Humanos , Adenosina Desaminase/genética , Irã (Geográfico) , Pesquisa
9.
Front Immunol ; 14: 1151166, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37388727

RESUMO

Introduction: Inborn errors of immunity (IEI) are characterized by a dysfunction of the immune system leading to increased susceptibility to infections, impaired immune regulation and cancer. We present a unique consanguineous family with a history of Hodgkin lymphoma, impaired EBV control and a late onset hemophagocytic lymphohistiocytosis (HLH). Methods and results: Overall, family members presented with variable impairment of NK cell and cytotoxic T cell degranulation and cytotoxicity. Exome sequencing identified homozygous variants in RAB27A, FBP1 (Fructose-1,6-bisphosphatase 1) and ACAD9 (Acyl-CoA dehydrogenase family member 9). Variants in RAB27A lead to Griscelli syndrome type 2, hypopigmentation and HLH predisposition. Discussion: Lymphoma is frequently seen in patients with hypomorphic mutations of genes predisposing to HLH. We hypothesize that the variants in FBP1 and ACAD9 might aggravate the clinical and immune phenotype, influence serial killing and lytic granule polarization by CD8 T cells. Understanding of the interplay between the multiple variants identified by whole exome sequencing (WES) is essential for correct interpretation of the immune phenotype and important for critical treatment decisions.


Assuntos
Acil-CoA Desidrogenases , Síndromes de Imunodeficiência , Linfoma , Doenças da Imunodeficiência Primária , Humanos , Vesícula , Metabolismo Energético , Genótipo , Síndromes de Imunodeficiência/genética , Doenças da Imunodeficiência Primária/genética , Proteínas rab27 de Ligação ao GTP/genética
10.
Nat Commun ; 14(1): 3708, 2023 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-37349293

RESUMO

We describe the first cases of germline biallelic null mutations in ARPC5, part of the Arp2/3 actin nucleator complex, in two unrelated patients presenting with recurrent and severe infections, early-onset autoimmunity, inflammation, and dysmorphisms. This defect compromises multiple cell lineages and functions, and when protein expression is reestablished in-vitro, the Arp2/3 complex conformation and functions are rescued. As part of the pathophysiological evaluation, we also show that interleukin (IL)-6 signaling is distinctively impacted in this syndrome. Disruption of IL-6 classical but not trans-signaling highlights their differential roles in the disease and offers perspectives for therapeutic molecular targets.


Assuntos
Complexo 2-3 de Proteínas Relacionadas à Actina , Actinas , Humanos , Complexo 2-3 de Proteínas Relacionadas à Actina/genética , Complexo 2-3 de Proteínas Relacionadas à Actina/metabolismo , Actinas/genética , Actinas/metabolismo , Movimento Celular , Mutação em Linhagem Germinativa , Citocinas/genética
11.
Allergy Asthma Clin Immunol ; 19(1): 13, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36810129

RESUMO

BACKGROUND: DCLRE1C gene mutation leads to Artemis deficiency, a severe form of combined immunodeficiency (SCID). Impaired DNA repair and block in early adaptive immunity maturation results in T-B-NK+ immunodeficiency associated with radiosensitivity. Recurrent infections early in life are the main characteristic of Artemis patients. METHOD: Among 5373 registered patients, 9 Iranian patients (33.3% female) with confirmed DCLRE1C mutation were identified since 1999-2022. The demographic, clinical, immunological and genetic features were collected through retrospective investigation of medical records and using next generation sequencing. RESULTS: Seven patients were born in a consanguineous family (77.8%). The median age of onset was 6.0 (5.0-17.0) months. Severe combined immunodeficiency (SCID) was clinically detected at a median (IQR) age of 7.0 (6.0-20.5) months, following a median diagnostic delay of 2.0 (1.0-3.5) months The most typical first presentation was pneumonia (44.4%) and otitis media (3.33%), followed by BCG lymphadenitis (22.2%) and gastroenteritis (11.1%). The most prevalent manifestations were respiratory tract infections (including otitis media) (66.6%) and chronic diarrhea (66.6%). In addition, juvenile idiopathic arthritis (P5) and celiac disease and idiopathic thrombocytopenic purpura (P9) as autoimmune disorders were reported in 2 patients. All patients had reduced B CD19+ and CD4+ cell counts. IgA deficiency occurred in 77.8% of individuals. CONCLUSION: Recurrent infections particulary respiratory tract infection and chronic diarrhea during the first months of life in patients born to consanguineous parents should raise the suspicion for inborn errors of immunity, even in the presence of normal growth and development.

12.
Sci Immunol ; 8(80): eabq5204, 2023 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-36763636

RESUMO

Patients with autosomal recessive (AR) IL-12p40 or IL-12Rß1 deficiency display Mendelian susceptibility to mycobacterial disease (MSMD) due to impaired IFN-γ production and, less commonly, chronic mucocutaneous candidiasis (CMC) due to impaired IL-17A/F production. We report six patients from four kindreds with AR IL-23R deficiency. These patients are homozygous for one of four different loss-of-function IL23R variants. All six patients have a history of MSMD, but only two suffered from CMC. We show that IL-23 induces IL-17A only in MAIT cells, possibly contributing to the incomplete penetrance of CMC in patients unresponsive to IL-23. By contrast, IL-23 is required for both baseline and Mycobacterium-inducible IFN-γ immunity in both Vδ2+ γδ T and MAIT cells, probably contributing to the higher penetrance of MSMD in these patients. Human IL-23 appears to contribute to IL-17A/F-dependent immunity to Candida in a single lymphocyte subset but is required for IFN-γ-dependent immunity to Mycobacterium in at least two lymphocyte subsets.


Assuntos
Interferon gama , Interleucina-23 , Infecções por Mycobacterium , Mycobacterium , Humanos , Predisposição Genética para Doença , Interleucina-17/genética , Interleucina-23/genética , Infecções por Mycobacterium/imunologia
13.
Blood Cells Mol Dis ; 99: 102726, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36696755

RESUMO

Leukocyte adhesion deficiency (LAD) is an immunodeficiency caused by defects in the adhesion of leukocytes (especially neutrophils) to the blood vessel wall. As a result, patients with LAD suffer from severe bacterial infections and impaired wound healing, accompanied by neutrophilia. In LAD-I, characterized directly after birth by delayed separation of the umbilical cord, mutations are found in ITGB2, the gene that encodes the ß subunit (CD18) of the ß2 integrins. In the rare LAD-II disease, the fucosylation of selectin ligands is disturbed, caused by mutations in SLC35C1, the gene that encodes a GDP-fucose transporter of the Golgi system. LAD-II patients lack the H and Lewis Lea and Leb blood group antigens. Finally, in LAD-III, the conformational activation of the hematopoietically expressed ß integrins is disturbed, leading to leukocyte and platelet dysfunction. This last syndrome is caused by mutations in FERMT3, encoding the kindlin-3 protein in all blood cells, involved in the regulation of ß integrin conformation. This article contains an update of the mutations that we consider to be relevant for the various forms of LAD.


Assuntos
Síndrome da Aderência Leucocítica Deficitária , Humanos , Adesão Celular/genética , Síndrome da Aderência Leucocítica Deficitária/genética , Antígenos CD18/genética , Antígenos CD18/metabolismo , Leucócitos , Mutação
14.
Fetal Pediatr Pathol ; 42(2): 259-262, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35608383

RESUMO

INTRODUCTION: Chediak-Higashi syndrome (CHS) is caused by dysfunction of lysosomal trafficking and presents with hypopigmentation, bleeding tendencies, neurological symptoms, and NK cell dysfunction. Hemophagocytic lymphohistiocytosis (HLH) can complicate CHS due to the abnormal function of NK cells. CASE PRESENTATION: This 1.5-year-old light-skinned gray-haired girl microscopically had abnormal hair pigment clumps and lilac inclusions in the myeloid series, characteristic of CHS. She presented with HLH, requiring treatment with etoposide and dexamethasone followed by cyclosporine and dexamethasone. CONCLUSION: CHS is one of the underlying primary causes of HLH.


Assuntos
Síndrome de Chediak-Higashi , Linfo-Histiocitose Hemofagocítica , Feminino , Humanos , Lactente , Síndrome de Chediak-Higashi/complicações , Síndrome de Chediak-Higashi/diagnóstico , Linfo-Histiocitose Hemofagocítica/complicações , Linfo-Histiocitose Hemofagocítica/diagnóstico , Pele , Proteínas de Transporte Vesicular , Dexametasona/uso terapêutico
15.
J Exp Med ; 220(1)2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36326697

RESUMO

Inborn errors of IFN-γ immunity can underlie tuberculosis (TB). We report three patients from two kindreds without EBV viremia or disease but with severe TB and inherited complete ITK deficiency, a condition associated with severe EBV disease that renders immunological studies challenging. They have CD4+ αß T lymphocytopenia with a concomitant expansion of CD4-CD8- double-negative (DN) αß and Vδ2- γδ T lymphocytes, both displaying a unique CD38+CD45RA+T-bet+EOMES- phenotype. Itk-deficient mice recapitulated an expansion of the γδ T and DN αß T lymphocyte populations in the thymus and spleen, respectively. Moreover, the patients' T lymphocytes secrete small amounts of IFN-γ in response to TCR crosslinking, mitogens, or forced synapse formation with autologous B lymphocytes. Finally, the patients' total lymphocytes secrete small amounts of IFN-γ, and CD4+, CD8+, DN αß T, Vδ2+ γδ T, and MAIT cells display impaired IFN-γ production in response to BCG. Inherited ITK deficiency undermines the development and function of various IFN-γ-producing T cell subsets, thereby underlying TB.


Assuntos
Receptores de Antígenos de Linfócitos T gama-delta , Tuberculose , Animais , Humanos , Camundongos , Interferon gama , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Antígenos de Linfócitos T gama-delta/genética , Subpopulações de Linfócitos T , Timo
16.
J Exp Med ; 219(10)2022 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-36094518

RESUMO

Human cells homozygous for rare loss-of-expression (LOE) TYK2 alleles have impaired, but not abolished, cellular responses to IFN-α/ß (underlying viral diseases in the patients) and to IL-12 and IL-23 (underlying mycobacterial diseases). Cells homozygous for the common P1104A TYK2 allele have selectively impaired responses to IL-23 (underlying isolated mycobacterial disease). We report three new forms of TYK2 deficiency in six patients from five families homozygous for rare TYK2 alleles (R864C, G996R, G634E, or G1010D) or compound heterozygous for P1104A and a rare allele (A928V). All these missense alleles encode detectable proteins. The R864C and G1010D alleles are hypomorphic and loss-of-function (LOF), respectively, across signaling pathways. By contrast, hypomorphic G996R, G634E, and A928V mutations selectively impair responses to IL-23, like P1104A. Impairment of the IL-23-dependent induction of IFN-γ is the only mechanism of mycobacterial disease common to patients with complete TYK2 deficiency with or without TYK2 expression, partial TYK2 deficiency across signaling pathways, or rare or common partial TYK2 deficiency specific for IL-23 signaling.


Assuntos
Síndrome de Job , TYK2 Quinase , Humanos , Interferon gama/metabolismo , Interleucina-23 , Síndrome de Job/genética , TYK2 Quinase/deficiência , TYK2 Quinase/genética , TYK2 Quinase/metabolismo
17.
Pediatr Rheumatol Online J ; 20(1): 78, 2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36064566

RESUMO

BACKGROUND: A20 haploinsufficiency (HA20) is a newly introduced autosomal dominant autoinflammatory disorder, also known as Behcet's-like disease. Some of the most common symptoms of the disease are recurrent oral, genital, and/or gastrointestinal (GI) ulcers, episodic fever, musculoskeletal symptoms, cutaneous lesions, and recurrent infections. Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening condition of multi-organ failure due to excessive immune activation. HLH has been reported in a few HA20 patients. Herein, we report two children with the primary presentation of HLH, with a mutation in TNFAIP3, in favor of HA20. CASE PRESENTATIONS: Our first patient was a 4-month-old boy who presented with fever, irritability, pallor, and hepatosplenomegaly. Pancytopenia, elevated ferritin, and decreased fibrinogen levels were found in laboratory evaluation. He was diagnosed with HLH and was treated with methylprednisolone and cyclosporine. Two years later, whole exome sequencing (WES) indicated a mutation in TNFAIP3 at NM_001270507: exon3: c.C386T, p.T129M, consistent with A20 haploinsufficiency. Etanercept, a TNF inhibitor, was prescribed, but the parents were reluctant to initiate the therapy. The patient passed away with the clinical picture of cerebral hemorrhage. The second patient was a 3-month-old boy who presented with a fever and hepatosplenomegaly. Laboratory evaluation found pancytopenia, hyperferritinemia, hypoalbuminemia, hypertriglyceridemia, and hypofibrinogenemia. With the establishment of the HLH diagnosis, he was treated with etoposide, dexamethasone, and cyclosporine, and recovered. WES results revealed a heterozygous de novo variant of TNFAIP3 (c. T824C in exon 6, 6q23.3) that leads to a proline to leucine amino acid change (p. L275P). He was treated with etanercept and has been symptom-free afterward. CONCLUSIONS: This report is a hypothesis for developing of the HLH phenotype in the presence of TNFAIP3 mutation. Our results provide a new perspective on the role of TNFAIP3 mutation in HLH phenotypes, but more extensive studies are required to confirm these preliminary results.


Assuntos
Ciclosporinas , Linfo-Histiocitose Hemofagocítica , Pancitopenia , Ciclosporinas/genética , Etanercepte , Haploinsuficiência/genética , Humanos , Linfo-Histiocitose Hemofagocítica/diagnóstico , Linfo-Histiocitose Hemofagocítica/genética , Masculino , Mutação , Fenótipo , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/genética
18.
Iran J Allergy Asthma Immunol ; 21(3): 232-240, 2022 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-35822674

RESUMO

Oral immunotherapy (OIT) is a novel approach to desensitization and tolerance induction in food allergy patients. This study aimed to design and implement a new wheat OIT protocol, evaluate its efficacy in tolerance induction, and assess specific immunoglobulin-E (IgE) and regulatory T cell changes. From 2015 to 2017, 26 patients with confirmed IgE-mediated hypersensitivity to wheat were treated via oral immunotherapy (OIT). Patients with prior anaphylactic episodes underwent OIT using the rush method. Specific IgE concentrations and the number of regulatory T cells (CD4+ CD25+ FOXP3+ T cells) were measured using Allergy Screen immunoblot assay and flow cytometry, respectively. This study was registered in the Iranian Registry of Clinical Trials (IRCT20181220042066N1). The results revealed success rates of 100% and 93.3% for desensitization and tolerance. Specific IgE was significantly reduced after 12 months of OIT. No significant change in regulatory T cell numbers was observed. In view of the promising findings of this study, the proposed OIT protocol could be viewed as an effective and valuable method to induce tolerance and desensitization in wheat allergic patients.


Assuntos
Dessensibilização Imunológica , Hipersensibilidade Alimentar , Administração Oral , Alérgenos/uso terapêutico , Dessensibilização Imunológica/métodos , Hipersensibilidade Alimentar/terapia , Humanos , Tolerância Imunológica , Imunoglobulina E , Fatores Imunológicos , Irã (Geográfico) , Triticum
20.
J Wound Care ; 31(5): 427-431, 2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35579316

RESUMO

Patients with chronic granulomatous disease, a primary immunodeficiency, experience granulomatous complications and recurrent life-threatening opportunistic bacterial and fungal infections. In this article, we report on a case of invasive aspergillosis in an eight-year-old boy with chronic granulomatous disease, who presented with pleural effusion and pneumonia, cerebral venous sinus thrombosis, and unusual skin lesions caused by Aspergillus fumigatus. Antifungal treatment with itraconazole and other antifungal agents, along with interferon-γ, was ineffective and the patient eventually died from cerebral venous sinus thrombosis, and intracerebral haemorrhage following increased intracranial pressure after one month. The diagnosis of invasive aspergillosis should be considered early in children presenting with invasive fungal infections, particularly those involving the central nervous system.


Assuntos
Aspergilose , Doença Granulomatosa Crônica , Infecções Fúngicas Invasivas , Trombose dos Seios Intracranianos , Antifúngicos/uso terapêutico , Aspergilose/complicações , Aspergilose/diagnóstico , Aspergilose/tratamento farmacológico , Criança , Doença Granulomatosa Crônica/complicações , Doença Granulomatosa Crônica/diagnóstico , Doença Granulomatosa Crônica/microbiologia , Humanos , Infecções Fúngicas Invasivas/complicações , Infecções Fúngicas Invasivas/tratamento farmacológico , Itraconazol/uso terapêutico , Masculino , Trombose dos Seios Intracranianos/complicações , Trombose dos Seios Intracranianos/tratamento farmacológico
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