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1.
J Clin Immunol ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31696364

RESUMO

Autosomal recessive agammaglobulinemia (ARA) is a primary immunodeficiency characterized by absent peripheral B cells, severe hypogammaglobulinemia, and absent BTK gene mutations. In ARA, mutations occur in genes encoding the pre-B cell receptor (pre-BCR) or downstream signaling proteins. In this work, we used candidate gene and whole-exome sequencing to investigate the molecular basis of ARA in 6 patients from 4 consanguineous North-African families. Sanger sequencing of candidate genes encoding the pre-BCR components (ΙGΗΜ, CD79A, CD79B, IGLL1, and VPREB1) was initially performed and determined the genetic defect in five patients. Two novel mutations in IGHM (p.Val378Alafs*1 and p.Ile184Serfs*21) were identified in three patients from two unrelated kindred and a novel nonsense mutation was identified in CD79A (p.Trp66*) in two siblings from a third kindred. Whole-exome sequencing (WES) was performed on the sixth patient who harbored a homozygous stop mutation at position 407 in the RAG2 gene (p.Glu407*). We concluded that conventional gene sequencing, especially when multiple genes are involved in the defect as is the case in ARA, is costly and time-consuming, resulting in delayed diagnosis that contributes to increased morbidity and mortality. In addition, it fails to identify the involvement of novel and unsuspected gene defects when the phenotype of the patients is atypical. WES has the potential to provide a rapid and more accurate genetic diagnosis in ARA, which is crucial for the treatment of the patients.

2.
Hum Vaccin Immunother ; : 1-4, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31596660

RESUMO

School-based vaccination, as a means to mitigate seasonal influenza outbreak, depends on attaining adequate coverage rate. We evaluated the potential of a fully subsidized school outreach vaccination (SOV) program to achieve epidemic prevention potential in Hong Kong. The purpose of this study was to evaluate the impact of SOV program 2018-2019 on influenza vaccination rates and influenza-like illness (ILI) in the primary school students and their household members during the influenza season. The vaccination rate was significantly higher in the schools offering SOV (intervention schools) (69.2% vs. 34.3%) than those not offering SOV (control schools) (p < .0001). The ILI rate was significantly reduced from 14.1% among non-vaccinated to 7.7% among vaccinated students (p < .0001). Influenza vaccine effectiveness against ILI was 45.3%. The vaccination rates of the household members were the same in both intervention and control schools except in the sub-group of preschool household members with the intervention significantly higher than the control group (43.8% vs. 32%, p < .0001). SOV program significantly improved influenza vaccine coverage, and the vaccine reduced ILI incidence. Extension of SOV program to all primary schools as well as kindergartens in Hong Kong could achieve epidemic prevention potential and should be evaluated.

3.
Front Immunol ; 10: 2189, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31572394

RESUMO

Talaromyces (Penicillium) marneffei is an AIDS-defining infection in Southeast Asia and is associated with high mortality. It is rare in non-immunosuppressed individuals, especially children. Little is known about host immune response and genetic susceptibility to this endemic fungus. Genetic defects in the interferon-gamma (IFN-γ)/STAT1 signaling pathway, CD40/CD40 ligand- and IL12/IL12-receptor-mediated crosstalk between phagocytes and T-cells, and STAT3-mediated Th17 differentiation have been reported in HIV-negative children with talaromycosis and other endemic mycoses such as histoplasmosis, coccidioidomycosis, and paracoccidioidomycosis. There is a need to design a diagnostic algorithm to evaluate such patients. In this article, we review a cohort of pediatric patients with disseminated talaromycosis referred to the Asian Primary Immunodeficiency Network for genetic diagnosis of PID. Using these illustrative cases, we propose a diagnostics pipeline that begins with immunoglobulin pattern (IgG, IgA, IgM, and IgE) and enumeration of lymphocyte subpopulations (T-, B-, and NK-cells). The former could provide clues for hyper-IgM syndrome and hyper-IgE syndrome. Flow cytometric evaluation of CD40L expression should be performed for patients suspected to have X-linked hyper-IgM syndrome. Defects in interferon-mediated JAK-STAT signaling are evaluated by STAT1 phosphorylation studies by flow cytometry. STAT1 hyperphosphorylation in response to IFN-α or IFN-γ and delayed dephosphorylation is diagnostic for gain-of-function STAT1 disorder, while absent STAT1 phosphorylation in response to IFN-γ but normal response to IFN-α is suggestive of IFN-γ receptor deficiency. This simple and rapid diagnostic algorithm will be useful in guiding genetic studies for patients with disseminated talaromycosis requiring immunological investigations.

4.
Clin Infect Dis ; 2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31086993

RESUMO

Primary B-cell immunodeficiencies are risk factors for the generation of vaccine-derived polioviruses. We report immunodeficiency-associated vaccine-derived poliovirus serotype 3 in an 11-week old boy with X-linked agammaglobulinemia. Unique characteristics of this case include early age of presentation, high viral evolutionary rate and that the child was perinatally exposed to HIV.

5.
Am J Med Genet C Semin Med Genet ; 181(2): 262-268, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30897304

RESUMO

Systemic lupus erythematosus (SLE) is a prototype autoimmune disease with extreme clinical heterogeneity and significant differences between populations. East Asian populations are known to have higher prevalence and more severe clinical manifestations for SLE than Europeans. The difference could be the result of genetic and environmental factors, and the interactions between them. Thus, identifying genetic associations from diverse populations provides an opportunity to better understand the genetic architecture of this heterogeneous disease. It is also necessary to elucidate population differences and to apply the findings in future stratified treatment of the disease, with ethnicity likely a major factor to consider. Indeed, it has shown that there are significant differences between East Asians and European populations in several genetic loci for SLE. Genetic studies on SLE are very active in East Asian countries and there have been close collaborations among scientists in this region. Here, we document some work done in this region on SLE genetic research and discuss the aspect of population differences.

6.
Artigo em Inglês | MEDLINE | ID: mdl-30903997

RESUMO

BACKGROUND: Drug allergy, or drug hypersensitivity, is a potentially fatal disorder, and patients labeled with drug allergies have restricted access to first-line treatments. Full knowledge of the characteristics associated with drug allergies and severe reactions during allergy evaluation is beneficial for appropriate risk stratification. OBJECTIVE: We sought to determine whether certain clinical characteristics are associated with drug allergies in Chinese children. METHODS: Charts were reviewed for ethnic Chinese patients less than 18 years old referred to our tertiary allergy center for suspected drug allergies and completed skin and drug provocative testing between 2005 to 2017. Univariate and multivariate analyses were performed on the age of onset of drug allergies, gender, and other atopy versus drug allergies. RESULTS: Out of 75 children, 18 (24%) had IgE-mediated drug allergies, while 8 (10.7%) had delayed drug hypersensitivities, with a cumulative 26 subjects (34.7%) with any drug hypersensitivity. There were positive independent associations between drug hypersensitivities onset age vs IgE-mediated drug allergies (odds ratio (OR) = 14.9, 95% confidence intervals (CIs) = 1.5-148.3, P = 0.017) and between male gender and IgE-mediated drug allergies (OR = 4.4, CIs = 1.2-16.4, P = 0.019). Age 13 years was the best cut-off for IgE-mediated drug allergies according to the receiver operating characteristic curve (P = 0.026). Older age group (OR = 24.0, CIs = 1.4-417.8, P = 0.024) and atopic dermatitis (OR = 8.2, CIs = 1.4-49.8, P = 0.015) were correlated with delayed drug hypersensitivities. CONCLUSIONS: While several previous studies suggested a higher prevalence of IgE-mediated drug allergies in younger adult females, older boys were more likely to have drug allergies for Chinese children.

7.
Epigenetics ; 14(4): 341-351, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30806140

RESUMO

Patients with paediatric-onset systemic lupus erythematosus (SLE) often present with more severe clinical courses than adult-onset patients. Although genome-wide DNA methylation (DNAm) profiling has been performed in adult-onset SLE patients, parallel data on paediatric-onset SLE are not available. Therefore, we undertook a genome-wide DNAm study in paediatric-onset SLE patients across multiple blood cell lineages. The DNAm profiles of four purified immune cell lineages (CD4 + T cells, CD8 + T cells, B cells and neutrophils) and whole blood were compared in 16 Chinese patients with paediatric-onset SLE and 13 healthy controls using the Illumina HumanMethylationEPIC BeadChip. Comparison of DNAm in whole blood and within each independent cell lineage identified a consistent pattern of loss of DNAm at 21 CpG sites overlapping 15 genes, which represented a robust, disease-specific DNAm signature for paediatric-onset SLE in our cohort. In addition, cell lineage-specific changes, involving both loss and gain of DNAm, were observed in both novel genes and genes with well-described roles in SLE pathogenesis. This study also highlights the importance of studying DNAm changes in different immune cell lineages rather than only whole blood, since cell type-specific DNAm changes facilitated the elucidation of the cell type-specific molecular pathophysiology of SLE.

8.
Pediatr Allergy Immunol ; 30(3): 378-386, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30716179

RESUMO

BACKGROUND: Chronic granulomatous disease (CGD) is a rare disease in China, and very little large-scale studies have been conducted to date. We aimed to investigate the clinical and genetic features of CGD in Chinese pediatric patients. METHODS: Pediatric patients with CGD from Beijing Children's Hospital, Capital Medical University, China, were enrolled from January 2006 to December 2016. RESULTS: A total of 159 pediatric patients with CGD were enrolled. The median age of clinical onset was 1.4 months, and 73% (116/159) had clinical onset symptoms before the 1 year of age. The most common site of invasion was the lungs. The lymph nodes, liver, and skin were more frequently invaded in X-linked (XL) CGD patients than in autosomal recessive (AR) CGD patients (P < 0.05). Approximately 64% (92/144) of the pediatric patients suffered from abnormal response to BCG vaccination. The most frequent pathogens were Aspergillus and Mycobacterium tuberculosis. Gene analysis indicated that 132 cases (89%, 132/147) harbored CYBB pathogenic variants, 7 (5%, 7/147) carried CYBA pathogenic variants, 4 (3%, 4/147) had NCF1 pathogenic variants, and 4 (3%, 4/147) had NCF2 pathogenic variants. The overall mortality rate in this study was 43%, particularly the patients were males, with CYBB mutant and did not receive HSCT treatment. CONCLUSIONS: Chronic granulomatous disease is a rare disease affecting Chinese children; however, it is often diagnosed at a later age, and thus, the mortality rate is relatively high. The prevalence and the severity of disease in XL-CGD are higher than AR-CGD.


Assuntos
Doença Granulomatosa Crônica/diagnóstico , NADPH Oxidases/genética , Adolescente , Anti-Infecciosos/uso terapêutico , Grupo com Ancestrais do Continente Asiático/genética , Criança , Pré-Escolar , China , Feminino , Testes Genéticos/métodos , Doença Granulomatosa Crônica/genética , Doença Granulomatosa Crônica/mortalidade , Humanos , Lactente , Recém-Nascido , Masculino , Mutação , Estudos Retrospectivos
9.
Bioinformatics ; 2018 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-30169743

RESUMO

Availability: http://wyanglab.org:3838/RefPanelWebsite/. Supplementary information: Supplementary data are available at Bioinformatics online.

10.
NPJ Genom Med ; 3: 19, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30109123

RESUMO

Currently, offering whole-exome sequencing (WES) via collaboration with an external laboratory is increasingly common. However, the receipt of a WES report can be merely the beginning of a continuing exploration process rather than the end of the diagnostic odyssey. The laboratory often does not have the information the physician has, and any discrepancies in variant interpretation must be addressed by a medical geneticist. In this study, we performed diagnostic WES of 104 patients with paediatric-onset genetic diseases. The post-exome review of WES reports by the clinical geneticist led to a more comprehensive assessment of variant pathogenicity in 16 cases. The overall diagnostic yield was 41% (n = 43). Among these 43 diagnoses, 51% (22/43) of the pathogenic variants were nucleotide changes that have not been previously reported. The time required for the post-exome review of the WES reports varied, and 26% (n = 27) of the reports required an extensive amount of time (>3 h) for the geneticist to review. In this predominantly Chinese cohort, we highlight the importance of discrepancies between global and ethnic-specific frequencies of a genetic variant that complicate variant interpretation and the significance of post-exome diagnostic modalities in genetic diagnosis using WES. The challenges faced by geneticists in interpreting WES reports are also discussed.

11.
Front Immunol ; 9: 1826, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30147693

RESUMO

Background: X-linked agammaglobulinemia (XLA) is a primary immunodeficiency caused by Bruton's tyrosine kinase (BTK) mutation. Patients are susceptible to severe enterovirus infections. The underlying mechanism remains unknown. BTK is involved in toll-like receptors pathway, which initiates antiviral responses including interferon (IFN) productions. Objective: To demonstrate type I and III IFN productions in dendritic cells of XLA patients is decreased in response to oral poliovirus vaccine (OPV) but not H1N1 virus. Methods: Monocyte-derived dendritic cells (MoDCs) were derived from nine XLA patients aged 22-32 years old and 23 buffy coats from Hong Kong Red Cross blood donors. LFM-A13 was used to inhibit BTK. OPV Sabin type 1 and H1N1 influenza virus were used to stimulate MoDCs with RPMI as mock stimulation. The antiviral cytokine productions and phenotypic maturation of MoDCs were determined 24 h post-stimulation. OPV RNA was determined at 0, 6, 12, and 24 h post-stimulation. Results: Upon OPV stimulation, IFN-α2, IFN-ß, and IFN-λ1 productions in MoDCs from XLA patients and BTK-inhibited MoDCs of healthy controls were significantly lower than that from healthy controls. Whereas upon H1N1 stimulation, the IFN-α2, IFN-ß, and IFN-λ1 productions were similar in MoDCs from XLA patients, BTK-inhibited MoDCs of healthy controls and healthy controls. The mean fluorescent intensities (MFI) of CD83, CD86, and MHC-II in MoDCs from XLA patients in response to OPV was similar to that in response to mock stimulation, while the MFI of CD83, CD86, and MHC-II were significantly higher in response to H1N1 stimulation than that in response to mock stimulation. Whereas, the MFI of CD83, CD86, and MHC-II in MoDCs of healthy controls were significantly higher in response to both OPV and H1N1 stimulation compared to that in response to mock stimulation. Conclusion: Production of type I and III IFN in response to OPV was deficient in MoDCs from XLA patients, but was normal in response to H1N1 due to deficient BTK function. Moreover, phenotypic maturation of MoDCs from XLA patients was impaired in response to OPV but not to H1N1. These selective impairments may account for the unique susceptibility of XLA patients toward severe enterovirus infections.

12.
Clin Immunol ; 195: 59-66, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30053428

RESUMO

X-linked hyper IgM Syndrome (XLHIGM), the most frequent form of the Hyper IgM syndromes is a primary immune deficiency resulting from a mutation in the CD40 ligand gene (CD40LG). We analyzed the clinical and laboratory features of ten patients with XLHIGM, who were diagnosed at a tertiary care hospital in North India. Most common infections were sinopulmonary infections (80%) and diarrhea (50%). Sclerosing cholangitis and necrotising fasciitis were noted in one patient each. Three novel mutations in CD40LG (c.429_429 delA, p. G144DfsX5; c.500 G > A, p.G167E and c.156 G > C, p.K52 N) were detected. In addition, we found one missense mutation, two splice site mutations and two large deletions, which have been previously reported. Four (4) patients had expired at the time of analysis. We report the first series of XLHIGM from North India where we have documented unique features such as pulmonary alveolar proteinosis and infections with Mycobacterium sp.

13.
Artigo em Inglês | MEDLINE | ID: mdl-29981563

RESUMO

A seven-year-old girl developed angioedema and a generalized, erythematous rash several hours after receiving lignocaine with adrenaline reproducible on provocative challenge, confirming the first known case of generalized delayed-type hypersensitivity to local anaesthetics with cross-reactivity to bupivacaine but not chloroprocaine.

14.
Methods Mol Biol ; 1833: 107-114, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30039367

RESUMO

Rapid development of next generation sequencing (NGS) technology has substantially improved our ability to detect genomic variations. However, unlike other variations, such as point mutations, insertions, and deletions, which can be identified in high sensitivities and specificities based on NGS reads, most of inversions, especially those shorter than 1 kb, remain difficult to detect. Here we introduce a new framework, SRinversion, which was developed specifically for detection of inversions shorter than 1 kb by splitting and realigning poorly mapped or unmapped reads of the NGS data.

16.
Arthritis Res Ther ; 20(1): 92, 2018 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-29724251

RESUMO

BACKGROUND: Systemic lupus erythematous (SLE) is a complex autoimmune disease with female predominance, particularly affecting those of childbearing age. We performed analysis of three genome-wide genotyping datasets of populations of both Chinese and European origin. METHODS: This study involved 5695 cases and 10,357 controls in the discovery stage. The lead signal on chromosome X was followed by replication in three additional Asian cohorts, with 2300 cases and 4244 controls in total. Conditional analysis of the known associated loci on chromosome X was also performed to further explore independent signals. RESULTS: Single-nucleotide polymorphism rs13440883 in GPR173 was found to be significantly associated with SLE (Pmeta = 7.53 × 10- 9, ORmeta= 1.16), whereas conditional analysis provided evidence of a potential independent signal in the L1CAM-IRAK1-MECP2 region in Asian populations (rs5987175 [LCA10]). CONCLUSIONS: We identified a novel SLE susceptibility locus on the X chromosome. This finding emphasizes the importance of the X chromosome in disease pathogenesis and highlights the role of sex chromosomes in the female bias of SLE.

17.
Ann Rheum Dis ; 77(7): 1078-1084, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29625966

RESUMO

OBJECTIVES: Systemic lupus erythematosus (SLE) is a prototype autoimmune disease with a strong genetic component in its pathogenesis. Through genome-wide association studies (GWAS), we recently identified 10 novel loci associated with SLE and uncovered a number of suggestive loci requiring further validation. This study aimed to validate those loci in independent cohorts and evaluate the role of SLE genetics in drug repositioning. METHODS: We conducted GWAS and replication studies involving 12 280 SLE cases and 18 828 controls, and performed fine-mapping analyses to identify likely causal variants within the newly identified loci. We further scanned drug target databases to evaluate the role of SLE genetics in drug repositioning. RESULTS: We identified three novel loci that surpassed genome-wide significance, including ST3AGL4 (rs13238909, pmeta=4.40E-08), MFHAS1 (rs2428, pmeta=1.17E-08) and CSNK2A2 (rs2731783, pmeta=1.08E-09). We also confirmed the association of CD226 locus with SLE (rs763361, pmeta=2.45E-08). Fine-mapping and functional analyses indicated that the putative causal variants in CSNK2A2 locus reside in an enhancer and are associated with expression of CSNK2A2 in B-lymphocytes, suggesting a potential mechanism of association. In addition, we demonstrated that SLE risk genes were more likely to be interacting proteins with targets of approved SLE drugs (OR=2.41, p=1.50E-03) which supports the role of genetic studies to repurpose drugs approved for other diseases for the treatment of SLE. CONCLUSION: This study identified three novel loci associated with SLE and demonstrated the role of SLE GWAS findings in drug repositioning.

18.
Am J Respir Cell Mol Biol ; 58(6): 684-695, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29220578

RESUMO

Pulmonary fibrosis is a chronic progressive lung disease with few treatments. Human mesenchymal stem cells (MSCs) have been shown to be beneficial in pulmonary fibrosis because they have immunomodulatory capacity. However, there is no reliable model to test the therapeutic effect of human MSCs in vivo. To mimic pulmonary fibrosis in humans, we established a novel bleomycin-induced pulmonary fibrosis model in humanized mice. With this model, the benefit of human MSCs in pulmonary fibrosis and the underlying mechanisms were investigated. In addition, the relevant parameters in patients with pulmonary fibrosis were examined. We demonstrate that human CD8+ T cells were critical for the induction of pulmonary fibrosis in humanized mice. Human MSCs could alleviate pulmonary fibrosis and improve lung function by suppressing bleomycin-induced human T-cell infiltration and proinflammatory cytokine production in the lungs of humanized mice. Importantly, alleviation of pulmonary fibrosis by human MSCs was mediated by the PD-1/programmed death-ligand 1 pathway. Moreover, abnormal PD-1 expression was found in circulating T cells and lung tissues of patients with pulmonary fibrosis. Our study supports the potential benefit of targeting the PD-1/programmed death-ligand 1 pathway in the treatment of pulmonary fibrosis.

19.
J Allergy Clin Immunol ; 142(2): 595-604.e16, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29155103

RESUMO

BACKGROUND: Autoimmune lymphoproliferative syndrome (ALPS) is a genetic disorder of lymphocyte homeostasis due to impaired apoptosis. It was initially regarded as a very rare disease, but recent studies show that it may be more common than previously thought. Defects in a couple of genes have been identified in a proportion of patients with ALPS, but around one-third of such patients remain undefined genetically. OBJECTIVE: We describe 2 siblings presenting with ALPS-like disease. This study aimed to identify the genetic cause responsible for this phenotype. METHODS: Whole-exome sequencing and molecular and functional analyses were used to identify and characterize the genetic defect. Clinical and immunological analysis was also performed and reported. RESULTS: The 2 patients presented with chronic lymphadenopathy, hepatosplenomegaly, autoimmune hemolytic anemia, immune thrombocytopenia, and the presence of antinuclear autoantibody and other autoantibodies, but normal double-negative T cells. They also suffered from recurrent infections. Novel compound heterozygous mutations of RASGRP1 encoding Ras guanyl nucleotide releasing protein 1 were identified in the 2 siblings. The mutations impaired T-cell receptor signaling, leading to defective T-cell activation and proliferation, as well as impaired activation-induced cell death of T cells. CONCLUSIONS: This study shows for the first time that RASGRP1 mutation should be considered in patients with ALPS-like disease. We also propose to investigate the intracellular proteins involved in the T-cell receptor signaling pathway in similar patients but with unknown genetic cause.

20.
Cell Mol Immunol ; 15(9): 827-837, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28413216

RESUMO

Natural killer (NK) cells are indispensable components of both the innate and adaptive immune response. However, their precise roles in the cross-talk between innate and adaptive immunity during influenza virus infection remain controversial. By comparing NK cell dynamics and activity under a sub-lethal dose and high dose of influenza virus infection, we showed that influenza virus PR8 directly infected NK cells during natural infection, which was consistent with our previous findings obtained from an in vitro investigation of human NK cells. The impairments in cytotoxicity and IFN-γ production by spleen NK cells following high-dose infection were accompanied by decreased virus-specific killing mediated by cytotoxic T lymphocytes (CTLs). Importantly, the weakened CTL activity could be reversed by adoptive transfer of spleen NK cells harvested from low-dose-infected mice but not healthy donors. Taken together, our data provide direct evidence supporting the contribution of NK cells to antiviral T-cell responses. This study also indicates that a novel NK-targeted immune evasion strategy is used by influenza virus to shrink both innate and adaptive immune responses.

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