Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 25
Filtrar
1.
N Engl J Med ; 386(24): 2295-2302, 2022 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-35704481

RESUMO

Lifelong immunosuppression is required for allograft survival after kidney transplantation but may not ultimately prevent allograft loss resulting from chronic rejection. We developed an approach that attempts to abrogate immune rejection and the need for post-transplantation immunosuppression in three patients with Schimke immuno-osseous dysplasia who had both T-cell immunodeficiency and renal failure. Each patient received sequential transplants of αß T-cell-depleted and CD19 B-cell-depleted haploidentical hematopoietic stem cells and a kidney from the same donor. Full donor hematopoietic chimerism and functional ex vivo T-cell tolerance was achieved, and the patients continued to have normal renal function without immunosuppression at 22 to 34 months after kidney transplantation. (Funded by the Kruzn for a Kure Foundation.).


Assuntos
Transplante de Células-Tronco Hematopoéticas , Síndromes de Imunodeficiência , Transplante de Rim , Síndrome Nefrótica , Osteocondrodisplasias , Doenças da Imunodeficiência Primária , Arteriosclerose/genética , Arteriosclerose/terapia , Rejeição de Enxerto/prevenção & controle , Humanos , Síndromes de Imunodeficiência/terapia , Rim/fisiologia , Transplante de Rim/efeitos adversos , Síndrome Nefrótica/genética , Síndrome Nefrótica/terapia , Osteocondrodisplasias/genética , Osteocondrodisplasias/terapia , Doenças da Imunodeficiência Primária/genética , Doenças da Imunodeficiência Primária/terapia , Embolia Pulmonar/genética , Embolia Pulmonar/terapia , Condicionamento Pré-Transplante/métodos
2.
J Exp Med ; 218(7)2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-33951726

RESUMO

The pioneer transcription factor (TF) PU.1 controls hematopoietic cell fate by decompacting stem cell heterochromatin and allowing nonpioneer TFs to enter otherwise inaccessible genomic sites. PU.1 deficiency fatally arrests lymphopoiesis and myelopoiesis in mice, but human congenital PU.1 disorders have not previously been described. We studied six unrelated agammaglobulinemic patients, each harboring a heterozygous mutation (four de novo, two unphased) of SPI1, the gene encoding PU.1. Affected patients lacked circulating B cells and possessed few conventional dendritic cells. Introducing disease-similar SPI1 mutations into human hematopoietic stem and progenitor cells impaired early in vitro B cell and myeloid cell differentiation. Patient SPI1 mutations encoded destabilized PU.1 proteins unable to nuclear localize or bind target DNA. In PU.1-haploinsufficient pro-B cell lines, euchromatin was less accessible to nonpioneer TFs critical for B cell development, and gene expression patterns associated with the pro- to pre-B cell transition were undermined. Our findings molecularly describe a novel form of agammaglobulinemia and underscore PU.1's critical, dose-dependent role as a hematopoietic euchromatin gatekeeper.


Assuntos
Agamaglobulinemia/genética , Cromatina/genética , Proteínas Proto-Oncogênicas/genética , Transativadores/genética , Adolescente , Adulto , Linfócitos B/fisiologia , Diferenciação Celular/genética , Linhagem Celular , Criança , Pré-Escolar , Células Dendríticas/fisiologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento/genética , Células HEK293 , Hematopoese/genética , Células-Tronco Hematopoéticas/fisiologia , Humanos , Lactente , Linfopoese/genética , Masculino , Mutação/genética , Células Precursoras de Linfócitos B/fisiologia , Células-Tronco/fisiologia , Adulto Jovem
3.
N Engl J Med ; 384(17): 1613-1622, 2021 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-33838625

RESUMO

BACKGROUND: Outcomes in children and adolescents with recurrent or progressive high-grade glioma are poor, with a historical median overall survival of 5.6 months. Pediatric high-grade gliomas are largely immunologically silent or "cold," with few tumor-infiltrating lymphocytes. Preclinically, pediatric brain tumors are highly sensitive to oncolytic virotherapy with genetically engineered herpes simplex virus type 1 (HSV-1) G207, which lacks genes essential for replication in normal brain tissue. METHODS: We conducted a phase 1 trial of G207, which used a 3+3 design with four dose cohorts of children and adolescents with biopsy-confirmed recurrent or progressive supratentorial brain tumors. Patients underwent stereotactic placement of up to four intratumoral catheters. The following day, they received G207 (107 or 108 plaque-forming units) by controlled-rate infusion over a period of 6 hours. Cohorts 3 and 4 received radiation (5 Gy) to the gross tumor volume within 24 hours after G207 administration. Viral shedding from saliva, conjunctiva, and blood was assessed by culture and polymerase-chain-reaction assay. Matched pre- and post-treatment tissue samples were examined for tumor-infiltrating lymphocytes by immunohistologic analysis. RESULTS: Twelve patients 7 to 18 years of age with high-grade glioma received G207. No dose-limiting toxic effects or serious adverse events were attributed to G207 by the investigators. Twenty grade 1 adverse events were possibly related to G207. No virus shedding was detected. Radiographic, neuropathological, or clinical responses were seen in 11 patients. The median overall survival was 12.2 months (95% confidence interval, 8.0 to 16.4); as of June 5, 2020, a total of 4 of 11 patients were still alive 18 months after G207 treatment. G207 markedly increased the number of tumor-infiltrating lymphocytes. CONCLUSIONS: Intratumoral G207 alone and with radiation had an acceptable adverse-event profile with evidence of responses in patients with recurrent or progressive pediatric high-grade glioma. G207 converted immunologically "cold" tumors to "hot." (Supported by the Food and Drug Administration and others; ClinicalTrials.gov number, NCT02457845.).


Assuntos
Neoplasias Encefálicas/terapia , Glioma/terapia , Terapia Viral Oncolítica , Adolescente , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/radioterapia , Criança , Pré-Escolar , Terapia Combinada , Feminino , Glioma/diagnóstico por imagem , Glioma/patologia , Glioma/radioterapia , Humanos , Estimativa de Kaplan-Meier , Células Matadoras Naturais , Contagem de Leucócitos , Masculino , Terapia Viral Oncolítica/efeitos adversos , Linfócitos T
4.
Front Immunol ; 12: 796065, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35003119

RESUMO

Rubella virus (RuV) has recently been found in association with granulomatous inflammation of the skin and several internal organs in patients with inborn errors of immunity (IEI). The cellular tropism and molecular mechanisms of RuV persistence and pathogenesis in select immunocompromised hosts are not clear. We provide clinical, immunological, virological, and histological data on a cohort of 28 patients with a broad spectrum of IEI and RuV-associated granulomas in skin and nine extracutaneous tissues to further delineate this relationship. Combined immunodeficiency was the most frequent diagnosis (67.8%) among patients. Patients with previously undocumented conditions, i.e., humoral immunodeficiencies, a secondary immunodeficiency, and a defect of innate immunity were identified as being susceptible to RuV-associated granulomas. Hematopoietic cell transplantation was the most successful treatment in this case series resulting in granuloma resolution; steroids, and TNF-α and IL-1R inhibitors were moderately effective. In addition to M2 macrophages, neutrophils were identified by immunohistochemical analysis as a novel cell type infected with RuV. Four patterns of RuV-associated granulomatous inflammation were classified based on the structural organization of granulomas and identity and location of cell types harboring RuV antigen. Identification of conditions that increase susceptibility to RuV-associated granulomas combined with structural characterization of the granulomas may lead to a better understanding of the pathogenesis of RuV-associated granulomas and discover new targets for therapeutic interventions.


Assuntos
Granuloma/imunologia , Inflamação/imunologia , Macrófagos/imunologia , Neutrófilos/imunologia , Vírus da Rubéola/fisiologia , Rubéola (Sarampo Alemão)/imunologia , Idoso , Antígenos Virais/metabolismo , Estudos de Coortes , Citocinas/metabolismo , Suscetibilidade a Doenças , Feminino , Doenças Genéticas Inatas , Transplante de Células-Tronco Hematopoéticas , Humanos , Imuno-Histoquímica , Síndromes de Imunodeficiência , Masculino , Pessoa de Meia-Idade , Receptores de Interleucina-1/antagonistas & inibidores , Rubéola (Sarampo Alemão)/complicações , Células Th2/imunologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores
5.
Arthritis Rheumatol ; 72(2): 326-334, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31513353

RESUMO

OBJECTIVE: To assess the benefit of the recombinant human interleukin-1 receptor antagonist anakinra in treating pediatric patients with secondary hemophagocytic lymphohistiocytosis (HLH)/macrophage activation syndrome (MAS) associated with rheumatic and nonrheumatic conditions. METHODS: A retrospective chart review of all anakinra-treated patients with secondary HLH/MAS was performed at Children's of Alabama from January 2008 through December 2016. Demographic, clinical, laboratory, and genetic characteristics, outcomes data, and information on concurrent treatments were collected from the records and analyzed using appropriate univariate statistical approaches to assess changes following treatment and associations between patient variables and outcomes. RESULTS: Forty-four patients with secondary HLH/MAS being treated with anakinra were identified in the electronic medical records. The median duration of hospitalization was 15 days. The mean pretreatment serum ferritin level was 33,316 ng/ml and dropped to 14,435 ng/ml (57% decrease) within 15 days of the start of anakinra treatment. The overall mortality rate in the cohort was 27%. Earlier initiation of anakinra (within 5 days of hospitalization) was associated with reduced mortality (P = 0.046), whereas thrombocytopenia (platelet count <100,000/µl) and STXBP2 mutations were both associated with increased mortality (P = 0.008 and P = 0.012, respectively). In considering patients according to their underlying diagnosis, those with systemic juvenile idiopathic arthritis (JIA) had the lowest mortality rate, with no deaths among the 13 systemic JIA patients included in the study (P = 0.006). In contrast, those with an underlying hematologic malignancy had the highest mortality rate, at 100% (n = 3). CONCLUSION: These findings suggest that anakinra appears to be effective in treating pediatric patients with non-malignancy-associated secondary HLH/MAS, especially when it is given early in the disease course and when administered to patients who have an underlying rheumatic disease.


Assuntos
Proteína Antagonista do Receptor de Interleucina 1/uso terapêutico , Linfo-Histiocitose Hemofagocítica/tratamento farmacológico , Síndrome de Ativação Macrofágica/tratamento farmacológico , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Estudos Retrospectivos , Resultado do Tratamento
6.
Oncoimmunology ; 8(12): e1678921, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31741780

RESUMO

Immunotherapy with oncolytic herpes simplex virus-1 therapy offers an innovative, targeted, less-toxic approach for treating brain tumors. However, a major obstacle in maximizing oncolytic virotherapy is a lack of comprehensive understanding of the underlying mechanisms that unfold in CNS tumors/associated microenvironments after infusion of virus. We demonstrate that our multiplex biomarker screening platform comprehensively informs changes in both topographical location and functional states of resident/infiltrating immune cells that play a role in neuropathology after treatment with HSV G207 in a pediatric Phase 1 patient. Using this approach, we identified robust infiltration of CD8+ T cells suggesting activation of the immune response following virotherapy; however there was a corresponding upregulation of checkpoint proteins PD-1, PD-L1, CTLA-4, and IDO revealing a potential role for checkpoint inhibitors. Such work may ultimately lead to an understanding of the governing pathobiology of tumors, thereby fostering development of novel therapeutics tailored to produce optimal responses.

7.
Pediatr Blood Cancer ; 66(6): e27649, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30802360

RESUMO

Germline or acquired mutations involving the GATA-binding protein gene (GATA2) have been linked to a variety of clinical conditions. In addition, patients harboring GATA2 mutations have a striking predisposition to develop myeloid malignancies, such as myelodysplastic syndrome or acute myeloid leukemia, but not acute lymphoblastic leukemia (ALL). We report here a unique occurrence of early T-cell precursor ALL in a young child with GATA2 haploinsufficiency.


Assuntos
Deficiência de GATA2/complicações , Haploinsuficiência , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Criança , Feminino , Humanos , Fenótipo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/etiologia , Prognóstico
8.
Am J Med Genet A ; 176(12): 2791-2797, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30216695

RESUMO

Phelan-McDermid syndrome (PMS, OMIM 606232) is a heterozygous contiguous gene microdeletion syndrome occurring at the distal region of chromosome 22q13. This deletion encompasses the SHANK3 gene at 22q13.33, which is thought to be the critical gene for the neurodevelopmental features seen in this syndrome. PMS is typically characterized by intellectual disability, autism spectrum disorder, absent to severely delayed speech, neonatal hypotonia, and dysmorphic features. Two patients presenting with classic clinical features of PMS have been reported to have interstitial microdeletions in the 22q13.2 region that map proximal to the SHANK3 gene (0.54 and 0.72 Mb, respectively). Here, we describe a 13-month-old girl with a de novo 1.16 Mb interstitial deletion in the 22q13.2 region who presented with global developmental delay, subtle dysmorphic features, and immunodeficiency. This deletion overlaps with the two previously published cases and five cases from the DECIPHER database. All eight patients share features common to patients with PMS including developmental delay and language delay, which suggests that this represents a previously unrecognized microdeletion syndrome in the 22q13.2 region. Our patient's deletion encompasses the TCF20 and TNFRSF13C genes, which are thought to play causative roles in the patient's neurodevelopmental and immunological features, respectively.


Assuntos
Receptor do Fator Ativador de Células B/genética , Transtornos Cromossômicos/diagnóstico , Transtornos Cromossômicos/genética , Fenótipo , Fatores de Transcrição/genética , Alelos , Deleção Cromossômica , Cromossomos Humanos Par 22/genética , Hibridização Genômica Comparativa , Análise Citogenética , Feminino , Estudos de Associação Genética , Humanos , Lactente , Mutação
9.
Vib Spectrosc ; 98: 1-7, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30662146

RESUMO

Colloidal silver (Ag) nanoparticles (AgNP) have been widely used for surface-enhanced Raman spectroscopy (SERS) applications. We report a simple, rapid and effective method to prepare AgNP colloids for SERS using the classic organic chemistry Ag mirror reaction with Tollens' reagent. The AgNP colloid prepared with this process was characterized using SEM, and the reaction conditions further optimized using SERS measurements. It was found that Ag mirror reaction conditions that included 20 mM AgNO3, 5 min reaction time, and 0.5 M glucose produced AgNP colloids with an average size of 319.1 nm (s.d ±128.1). These AgNP colloids exhibited a significant SERS response when adenine was used as the reporter molecule. The usefulness of these new AgNP colloids was demonstrated by detecting the nucleotides adenosine 5'-monophosphate (AMP), guanosine 5'-monophosphate (GMP), cytidine 5'-monophosphate (CMP), and uridine 5'-monophosphate (UMP). A detection limit of 500 nM for AMP was achieved with the as-prepared AgNP colloid. The bacterium Mycoplasma pneumoniae was also easily detected in laboratory culture with these SERS substrates. These findings attest to the applicability of this AgNP colloid for the sensitive and specific detection of both small biomolecules and microorganisms.

10.
Curr Rheumatol Rep ; 16(9): 439, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25086802

RESUMO

Macrophage activation syndrome (MAS), typically presenting beyond the first year of life, is an often lethal cousin of familial hemophagocytic lymphohistiocytosis (fHLH). Defects in natural killer (NK) cell and CD8 T cell cytotoxicity result in a pro-inflammatory cytokine storm, cytopenia, coagulopathy, and multi-organ system dysfunction. MAS can occur in association with infections (herpes viruses), cancer (leukemia), immune deficient states (post-transplantation), and in autoimmune (systemic lupus erythematosus) and autoinflammatory conditions (systemic juvenile idiopathic arthritis). The distinction between fHLH, the result of homozygous defects in cytolytic pathway genes, and MAS is becoming blurred with the identification of single or multiple mutations in the same cytolytic pathway genes in patients with later onset MAS. Here, we review the literature and present novel cytolytic pathway gene mutations identified in children with MAS. We study the inhibitory effect of one these novel mutations on NK cell function to suggest a direct link between fHLH and MAS.


Assuntos
Citotoxicidade Imunológica/genética , Síndrome de Ativação Macrofágica/genética , Mutação , Artrite Juvenil/genética , Artrite Juvenil/imunologia , Linfócitos T CD8-Positivos/imunologia , Humanos , Células Matadoras Naturais/imunologia , Linfo-Histiocitose Hemofagocítica/genética , Linfo-Histiocitose Hemofagocítica/imunologia , Síndrome de Ativação Macrofágica/imunologia , Proteínas Munc18/genética
11.
J Allergy Clin Immunol ; 133(6): 1667-75, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24797421

RESUMO

BACKGROUND: Autosomal recessive loss-of-function mutations in dedicator of cytokinesis 8 (DOCK8) cause a combined immunodeficiency characterized by atopy, recurrent infections, and cancer susceptibility. A genotype-phenotype explanation for the variable disease expression is lacking. OBJECTIVE: We investigated whether reversions contributed to the variable disease expression. METHODS: Patients followed at the National Institutes of Health's Clinical Center were studied. We performed detailed genetic analyses and intracellular flow cytometry to detect DOCK8 protein expression within lymphocyte subsets. RESULTS: We identified 17 of 34 DOCK8-deficient patients who had germline mutations with variable degrees of reversion caused by somatic repair. Somatic repair of the DOCK8 mutations resulted from second-site mutation, original-site mutation, gene conversion, and intragenic crossover. Higher degrees of reversion were associated with recombination-mediated repair. DOCK8 expression was restored primarily within antigen-experienced T cells or natural killer cells but less so in naive T or B cells. Several patients exhibited multiple different repair events. Patients who had reversions were older and had less severe allergic disease, although infection susceptibility persisted. No patients were cured without hematopoietic cell transplantation. CONCLUSIONS: In patients with DOCK8 deficiency, only certain combinations of germline mutations supported secondary somatic repair. Those patients had an ameliorated disease course with longer survival but still had fatal complications or required hematopoietic cell transplantation. These observations support the concept that some DOCK8-immunodeficient patients have mutable mosaic genomes that can modulate disease phenotype over time.


Assuntos
Fatores de Troca do Nucleotídeo Guanina/genética , Síndromes de Imunodeficiência/genética , Mutação , Fenótipo , Adolescente , Subpopulações de Linfócitos B/imunologia , Subpopulações de Linfócitos B/metabolismo , Criança , Pré-Escolar , Análise Mutacional de DNA , Reparo do DNA , Genótipo , Mutação em Linhagem Germinativa , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Humanos , Síndromes de Imunodeficiência/diagnóstico , Síndromes de Imunodeficiência/mortalidade , Imunofenotipagem , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo
12.
Infect Immun ; 82(4): 1657-65, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24491573

RESUMO

Ureaplasma species commonly colonize the adult urogenital tract and are implicated in invasive diseases of adults and neonates. Factors that permit the organisms to cause chronic colonization or infection are poorly understood. We sought to investigate whether host innate immune responses, specifically, antimicrobial peptides (AMPs), are involved in determining the outcome of Ureaplasma infections. THP-1 cells, a human monocytoid tumor line, were cocultured with Ureaplasma parvum and U. urealyticum. Gene expression levels of a variety of host defense genes were quantified by real-time PCR. In vitro antimicrobial activities of synthetic AMPs against Ureaplasma spp. were determined using a flow cytometry-based assay. Chromosomal histone modifications in host defense gene promoters were tested by chromatin immunoprecipitation (ChIP). DNA methylation status in the AMP promoter regions was also investigated. After stimulation with U. parvum and U. urealyticum, the expression of cell defense genes, including the AMP genes (DEFB1, DEFA5, DEFA6, and CAMP), was significantly downregulated compared to that of TNFA and IL-8, which were upregulated. In vitro flow cytometry-based antimicrobial assay revealed that synthetic peptides LL-37, hBD-3, and hBD-1 had activity against Ureaplasma spp. Downregulation of the AMP genes was associated with chromatin modification alterations, including the significantly decreased histone H3K9 acetylation with U. parvum infection. No DNA methylation status changes were detected upon Ureaplasma infection. In conclusion, AMPs have in vitro activity against Ureaplasma spp., and suppression of AMP expression might be important for the organisms to avoid this aspect of the host innate immune response and to establish chronic infection and colonization.


Assuntos
Imunidade Inata/fisiologia , Infecções por Ureaplasma/metabolismo , Ureaplasma/fisiologia , alfa-Defensinas/fisiologia , beta-Defensinas/fisiologia , Linhagem Celular Tumoral , Cromatina/genética , Metilação de DNA/fisiologia , Regulação para Baixo , Citometria de Fluxo , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Humanos , Regiões Promotoras Genéticas/fisiologia , Reação em Cadeia da Polimerase em Tempo Real , Infecções por Ureaplasma/genética , alfa-Defensinas/metabolismo , beta-Defensinas/metabolismo
13.
Nat Immunol ; 15(1): 88-97, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24165795

RESUMO

The p110δ subunit of phosphatidylinositol-3-OH kinase (PI(3)K) is selectively expressed in leukocytes and is critical for lymphocyte biology. Here we report fourteen patients from seven families who were heterozygous for three different germline, gain-of-function mutations in PIK3CD (which encodes p110δ). These patients presented with sinopulmonary infections, lymphadenopathy, nodular lymphoid hyperplasia and viremia due to cytomegalovirus (CMV) and/or Epstein-Barr virus (EBV). Strikingly, they had a substantial deficiency in naive T cells but an over-representation of senescent effector T cells. In vitro, T cells from patients exhibited increased phosphorylation of the kinase Akt and hyperactivation of the metabolic checkpoint kinase mTOR, enhanced glucose uptake and terminal effector differentiation. Notably, treatment with rapamycin to inhibit mTOR activity in vivo partially restored the abundance of naive T cells, largely 'rescued' the in vitro T cell defects and improved the clinical course.


Assuntos
Senescência Celular/genética , Mutação em Linhagem Germinativa , Síndromes de Imunodeficiência/genética , Fosfatidilinositol 3-Quinases/genética , Linfócitos T/metabolismo , Antibióticos Antineoplásicos/uso terapêutico , Diferenciação Celular/genética , Células Cultivadas , Classe I de Fosfatidilinositol 3-Quinases , Infecções por Citomegalovirus/sangue , Infecções por Citomegalovirus/genética , Infecções por Citomegalovirus/virologia , Infecções por Vírus Epstein-Barr/sangue , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/virologia , Feminino , Genes Dominantes , Humanos , Immunoblotting , Síndromes de Imunodeficiência/tratamento farmacológico , Masculino , Linhagem , Fosfatidilinositol 3-Quinases/química , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Sirolimo/uso terapêutico , Serina-Treonina Quinases TOR/metabolismo , Viremia/tratamento farmacológico , Viremia/genética , Viremia/virologia
14.
J Thorac Cardiovasc Surg ; 147(5): 1587-1593.e1, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24035378

RESUMO

BACKGROUND: Hypogammaglobulinemia has been reported after cardiac surgery and may be associated with adverse outcomes. We sought to define baseline immunoglobulin (Ig) concentration in neonates and infants with congenital heart disease, determine their course after cardiopulmonary bypass (CPB), and determine if post-CPB hypogammaglobulinemia was associated with increased morbidity. METHODS: This was a single-center, retrospective analysis of infants who underwent cardiac surgery with CPB between June 2010 and December 2011. The Ig concentration was obtained from banked plasma of 47 patients from a prior study (pre-CPB, immediately post-CPB, and 24 and 48 hours post-CPB). In addition, any Ig levels drawn for clinical purposes after CPB were included. Ig levels were excluded if drawn after chylothorax diagnosis or intravenous IgG administration. RESULTS: The median age was 7 days. Preoperative Ig concentration was similar to that described in healthy children. IgG level decreased to less than 50% of preoperative concentration by 24-hour post-CPB and failed to recover by 7 days. Of 47 patients, 25 (53%) had low IgG (<248 mg/dL) after CPB. Despite no difference in demographics or risk factors between patients with low and normal IgG, low IgG patients had more positive fluid balance at 24 hours and increased proinflammatory plasma cytokine levels, duration of mechanical ventilation, and cardiac intensive care unit length of stay. In addition, low IgG patients had an increased incidence of postoperative infections (40% vs 14%; P = .056). CONCLUSIONS: Hypogammaglobulinemia occurs in half of infants after CPB. Its association with fluid overload and increased inflammatory cytokines suggests it may result from capillary leak. Postoperative hypogammaglobulinemia is associated with increased morbidity, including more secondary infections.


Assuntos
Agamaglobulinemia/imunologia , Ponte Cardiopulmonar/efeitos adversos , Cardiopatias Congênitas/cirurgia , Injúria Renal Aguda/epidemiologia , Agamaglobulinemia/sangue , Agamaglobulinemia/diagnóstico , Agamaglobulinemia/epidemiologia , Alabama/epidemiologia , Biomarcadores/sangue , Permeabilidade Capilar , Infecção Hospitalar/epidemiologia , Citocinas/sangue , Feminino , Humanos , Imunoglobulinas/sangue , Incidência , Recém-Nascido , Mediadores da Inflamação/sangue , Unidades de Terapia Intensiva Neonatal , Tempo de Internação , Masculino , Respiração Artificial , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Equilíbrio Hidroeletrolítico
15.
Hum Mutat ; 34(4): 587-94, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23316014

RESUMO

Missense mutations affecting membrane-bound transcription factor protease site 2 (MBTPS2) have been associated with Ichthyosis Follicularis with Atrichia and Photophobia (IFAP) syndrome with or without BRESHECK syndrome, with keratosis follicularis spinulosa decalvans, and Olmsted syndrome. This metalloprotease activates, by intramembranous trimming in conjunction with the protease MBTPS1, regulatory factors involved in sterol control of transcription and in cellular stress response. In this study, 11 different MBTPS2 missense mutations detected in patients from 13 unrelated families were correlated with the clinical phenotype, with their effect on cellular growth in media without lipids, and their potential role for sterol control of transcription. Seven variants were novel [c.774C>G (p.I258M); c.758G>C (p.G253A); c.686T>C (p.F229S); c.1427T>C (p.L476S); c.1430A>T (p.D477V); c.1499G>A (p.G500D); c.1538T>C (p.L513P)], four had previously been reported in unrelated sibships [c.261G>A (p.M87I); c.1286G>A (p.R429H); c.1424T>C (p.F475S); c.1523A>G (p.N508S)]. In the enzyme, the mutations cluster in transmembrane domains. Amino-acid exchanges near the active site are more detrimental to functionality of the enzyme and, clinically, associated with more severe phenotypes. In male patients, a genotype-phenotype correlation begins to emerge, linking the site of the mutation in MBTPS2 with the clinical outcome described as IFAP syndrome with or without BRESHECK syndrome, keratosis follicularis spinulosa decalvans, X-linked, Olmsted syndrome, or possibly further X-linked traits with an oculocutaneous component.


Assuntos
Alopecia/genética , Estudos de Associação Genética , Ictiose/genética , Metaloendopeptidases/genética , Mutação de Sentido Incorreto , Fotofobia/genética , Adolescente , Alelos , Alopecia/diagnóstico , Animais , Linhagem Celular , Criança , Pré-Escolar , Feminino , Teste de Complementação Genética , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico , Doenças Genéticas Ligadas ao Cromossomo X/genética , Humanos , Ictiose/diagnóstico , Masculino , Metaloendopeptidases/química , Metaloendopeptidases/metabolismo , Repetições de Microssatélites , Fenótipo , Fotofobia/diagnóstico , Polimorfismo de Nucleotídeo Único , Transporte Proteico , Dermatopatias Genéticas/diagnóstico , Dermatopatias Genéticas/genética , Adulto Jovem
16.
J Clin Invest ; 122(10): 3769-80, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23006327

RESUMO

The Fc receptor on NK cells, FcγRIIIA (CD16), has been extensively studied for its role in mediating antibody-dependent cellular cytotoxicity (ADCC). A homozygous missense mutation in CD16 (encoding a L66H substitution) is associated with severe herpesvirus infections in rare patients. Here, we identified a new patient with this CD16 mutation and compared the patient's NK cells to those of the originally reported patient. Patients with the L66H mutation had intact ADCC, but deficient spontaneous NK cell cytotoxicity and decreased surface expression of CD2, a coactivation receptor. Mechanistic studies in a human NK cell line, NK-92, demonstrated that CD16 expression correlated with CD2 surface levels and enabled killing of a melanoma cell line typically resistant to CD16-deficient NK-92 cells. An association between CD16 and CD2 was identified biochemically and at the immunological synapse, which elicited CD16 signaling after CD2 engagement. Stable expression of CD16 L66H in NK-92 cells recapitulated the patient phenotype, abrogating association of CD16 with CD2 as well as CD16 signaling after CD2 ligation. Thus, CD16 serves a role in NK cell-mediated spontaneous cytotoxicity through a specific association with CD2 and represents a potential mechanism underlying a human congenital immunodeficiency.


Assuntos
Síndromes de Imunodeficiência/genética , Células Matadoras Naturais/imunologia , Mutação de Sentido Incorreto , Receptores de IgG/genética , Adolescente , Citotoxicidade Celular Dependente de Anticorpos , Antígenos CD2/biossíntese , Antígenos CD2/imunologia , Hiperplasia do Linfonodo Gigante/etiologia , Hiperplasia do Linfonodo Gigante/virologia , Linhagem Celular/imunologia , Linhagem Celular Tumoral , Pré-Escolar , Citotoxicidade Imunológica , Suscetibilidade a Doenças , Infecções por Vírus Epstein-Barr/etiologia , Feminino , Proteínas Ligadas por GPI/química , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/imunologia , Genótipo , Infecções por Herpesviridae/etiologia , Humanos , Síndromes de Imunodeficiência/imunologia , Sinapses Imunológicas , Masculino , Melanoma/imunologia , Modelos Moleculares , Infecções por Papillomavirus/etiologia , Conformação Proteica , Receptores de IgG/química , Receptores de IgG/imunologia , Adulto Jovem
17.
PLoS One ; 5(12): e14417, 2010 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-21203444

RESUMO

Mycoplasma pneumoniae (Mp), a common cause of pneumonia, is associated with asthma; however, the mechanisms underlying this association remain unclear. We investigated the cellular immune response to Mp in mice. Intranasal inoculation with Mp elicited infiltration of the lungs with neutrophils, monocytes and macrophages. Systemic depletion of macrophages, but not neutrophils, resulted in impaired clearance of Mp from the lungs. Accumulation and activation of macrophages were decreased in the lungs of MyD88(-/-) mice and clearance of Mp was impaired, indicating that MyD88 is a key signaling protein in the anti-Mp response. MyD88-dependent signaling was also required for the Mp-induced activation of NFκB, which was essential for macrophages to eliminate the microbe in vitro. Thus, MyD88-NFκB signaling in macrophages is essential for clearance of Mp from the lungs.


Assuntos
Pulmão/imunologia , Pulmão/microbiologia , Macrófagos/imunologia , Mycoplasma pneumoniae/imunologia , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Animais , Adesão Celular , Sistema Imunitário , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Monócitos/imunologia , Monócitos/microbiologia , Neutrófilos/imunologia , Neutrófilos/microbiologia , Fagocitose , Transdução de Sinais
18.
Microb Pathog ; 44(4): 286-92, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18042342

RESUMO

We have previously described the activation of RBL-2H3 mast cells for IL-4 production by Mycoplasma pneumoniae but the mechanism remains unclear. M. pneumoniae binds eukaryotic cells primarily through sialoglycoproteins on the target cell surface. This study was undertaken to determine whether the sialated FcepsilonRI alpha chain on RBL cells is important for M. pneumoniae-induced IL-4 production. We found that IgE-mediated IL-4 release by a series of RBL sublines correlated with the release induced by M. pneumoniae. Further, aggregation of FcgammaRII (CD32) in RBL cells using a monoclonal antibody inhibited both IgE-mediated and mycoplasma-induced IL-4 production, providing further evidence for an Fc receptor-mediated mechanism of activation. To examine the role of FcepsilonRI in mycoplasma-induced IL-4 release, we created stably transfected RBL sublines using a vector expressing a short hairpin sequence designed to inhibit message for the FcepsilonRI alpha chain. IgE-induced IL-4 production by the transfected sublines was reduced in similar proportion to the degree of message suppression. M. pneumoniae-induced IL-4 production in the four transfected sublines was completely blocked in contrast to results with the controls or parent RBL cells. We conclude that the heavily glycosylated FcepsilonRI alpha chain is required for activation of mast cells for IL-4 production by M. pneumoniae.


Assuntos
Interleucina-4/metabolismo , Mastócitos/imunologia , Mastócitos/microbiologia , Mycoplasma pneumoniae/imunologia , Receptores de IgE/genética , Animais , Anticorpos Monoclonais/imunologia , Linhagem Celular Tumoral , Técnicas de Cocultura , Humanos , Imunoglobulina E/imunologia , Imunoglobulina E/metabolismo , Mastócitos/metabolismo , Interferência de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , Ratos , Receptores de IgE/imunologia , Receptores de IgE/metabolismo
19.
BMC Med Genet ; 8: 41, 2007 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-17605793

RESUMO

BACKGROUND: Autoimmune lymphoproliferative syndrome (ALPS) is a disorder of lymphocyte homeostasis and immunological tolerance due primarily to genetic defects in Fas (CD95/APO-1; TNFRSF6), a cell surface receptor that regulates apoptosis and its signaling apparatus. METHODS: Fas ligand gene mutations from ALPS patients were identified through cDNA and genomic DNA sequencing. Molecular and biochemical assessment of these mutant Fas ligand proteins were carried out by expressing the mutant FasL cDNA in mammalian cells and analysis its effects on Fas-mediated programmed cell death. RESULTS: We found an ALPS patient that harbored a heterozygous A530G mutation in the FasL gene that replaced Arg with Gly at position 156 in the protein's extracellular Fas-binding region. This produced a dominant-interfering FasL protein that bound to the wild-type FasL protein and prevented it from effectively inducing apoptosis. CONCLUSION: Our data explain how a naturally occurring heterozygous human FasL mutation can dominantly interfere with normal FasL apoptotic function and lead to an ALPS phenotype, designated Type Ib.


Assuntos
Apoptose/genética , Doenças Autoimunes/genética , Proteína Ligante Fas/genética , Transtornos Linfoproliferativos/genética , Adolescente , Adulto , Apoptose/imunologia , Doenças Autoimunes/imunologia , Citotoxicidade Imunológica , Proteína Ligante Fas/imunologia , Feminino , Heterozigoto , Humanos , Células Jurkat , Transtornos Linfoproliferativos/imunologia , Masculino , Modelos Moleculares , Mutação , Subpopulações de Linfócitos T/imunologia , Transfecção
20.
Clin Rheumatol ; 26(9): 1537-9, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17047893

RESUMO

Behçet's disease (BD) is a systemic vasculitis that may involve a variety of organs. We describe a girl with oculocutaneous albinism (OCA) who, on initial evaluation for popliteal artery occlusion, was noted to have multiple cardiac thrombi. She later developed hemoptysis, which was the result of bilateral pulmonary artery aneurysms. Her clinical picture was consistent with BD. She was initially treated with prednisone and cyclophosphamide, followed by maintenance therapy with infliximab. This case describes a unique patient with OCA who developed BD with large pulmonary aneurysms and has remained stable for over 1 year while receiving infliximab.


Assuntos
Albinismo Oculocutâneo/complicações , Aneurisma/etiologia , Síndrome de Behçet/complicações , Cardiopatias/etiologia , Trombose/etiologia , Adolescente , Negro ou Afro-Americano , Anticorpos Monoclonais/uso terapêutico , Síndrome de Behçet/diagnóstico , Síndrome de Behçet/tratamento farmacológico , Feminino , Humanos , Infliximab , Artéria Pulmonar/fisiopatologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Vasculite/tratamento farmacológico , Vasculite/etiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA