RESUMO
The molecular basis of the incomplete penetrance of monogenic disorders is unclear. We describe here eight related individuals with autosomal recessive TIRAP deficiency. Life-threatening staphylococcal disease occurred during childhood in the proband, but not in the other seven homozygotes. Responses to all Toll-like receptor 1/2 (TLR1/2), TLR2/6, and TLR4 agonists were impaired in the fibroblasts and leukocytes of all TIRAP-deficient individuals. However, the whole-blood response to the TLR2/6 agonist staphylococcal lipoteichoic acid (LTA) was abolished only in the index case individual, the only family member lacking LTA-specific antibodies (Abs). This defective response was reversed in the patient, but not in interleukin-1 receptor-associated kinase 4 (IRAK-4)-deficient individuals, by anti-LTA monoclonal antibody (mAb). Anti-LTA mAb also rescued the macrophage response in mice lacking TIRAP, but not TLR2 or MyD88. Thus, acquired anti-LTA Abs rescue TLR2-dependent immunity to staphylococcal LTA in individuals with inherited TIRAP deficiency, accounting for incomplete penetrance. Combined TIRAP and anti-LTA Ab deficiencies underlie staphylococcal disease in this patient.
Assuntos
Anticorpos Monoclonais/administração & dosagem , Lipopolissacarídeos/metabolismo , Glicoproteínas de Membrana/deficiência , Receptores de Interleucina-1/deficiência , Infecções Estafilocócicas/genética , Infecções Estafilocócicas/imunologia , Ácidos Teicoicos/metabolismo , Imunidade Adaptativa , Criança , Feminino , Fibroblastos/metabolismo , Humanos , Imunidade Inata , Lipopolissacarídeos/imunologia , Macrófagos/imunologia , Masculino , Glicoproteínas de Membrana/análise , Glicoproteínas de Membrana/genética , Monócitos/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Linhagem , Fagócitos/metabolismo , Mutação Puntual , Isoformas de Proteínas/análise , Isoformas de Proteínas/genética , Receptores de Interleucina-1/análise , Receptores de Interleucina-1/genética , Infecções Estafilocócicas/tratamento farmacológico , Ácidos Teicoicos/imunologia , Receptor 2 Toll-Like/metabolismo , Receptores Toll-Like/agonistas , Receptores Toll-Like/metabolismoRESUMO
We report the clinical description and molecular dissection of a new fatal human inherited disorder characterized by chronic autoinflammation, invasive bacterial infections and muscular amylopectinosis. Patients from two kindreds carried biallelic loss-of-expression and loss-of-function mutations in HOIL1 (RBCK1), a component of the linear ubiquitination chain assembly complex (LUBAC). These mutations resulted in impairment of LUBAC stability. NF-κB activation in response to interleukin 1ß (IL-1ß) was compromised in the patients' fibroblasts. By contrast, the patients' mononuclear leukocytes, particularly monocytes, were hyper-responsive to IL-1ß. The consequences of human HOIL-1 and LUBAC deficiencies for IL-1ß responses thus differed between cell types, consistent with the unique association of autoinflammation and immunodeficiency in these patients. These data suggest that LUBAC regulates NF-κB-dependent IL-1ß responses differently in different cell types.
Assuntos
Doença de Depósito de Glicogênio Tipo IV/genética , Doenças Hereditárias Autoinflamatórias/genética , Síndromes de Imunodeficiência/genética , NF-kappa B/metabolismo , Ubiquitina-Proteína Ligases/genética , Infecções Bacterianas/genética , Infecções Bacterianas/imunologia , Proteínas de Ciclo Celular/genética , Linhagem Celular , Fibroblastos/imunologia , Fibroblastos/metabolismo , Humanos , Síndromes de Imunodeficiência/metabolismo , Interleucina-1beta/metabolismo , Monócitos/imunologia , Monócitos/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Proteínas Repressoras/genética , Fatores de Transcrição , Ubiquitina-Proteína Ligases/deficiência , Ubiquitina-Proteína Ligases/metabolismo , UbiquitinaçãoRESUMO
Human inborn errors of IFN-γ underlie mycobacterial disease, due to insufficient IFN-γ production by lymphoid cells, impaired myeloid cell responses to this cytokine, or both. We report four patients from two unrelated kindreds with intermittent monocytosis and mycobacterial disease, including bacillus Calmette-Guérin-osis and disseminated tuberculosis, and without any known inborn error of IFN-γ. The patients are homozygous for ZNFX1 variants (p.S959* and p.E1606Rfs*10) predicted to be loss of function (pLOF). There are no subjects homozygous for pLOF variants in public databases. ZNFX1 is a conserved and broadly expressed helicase, but its biology remains largely unknown. It is thought to act as a viral double-stranded RNA sensor in mice, but these patients do not suffer from severe viral illnesses. We analyze its subcellular localization upon overexpression in A549 and HeLa cell lines and upon stimulation of THP1 and fibroblastic cell lines. We find that this cytoplasmic protein can be recruited to or even induce stress granules. The endogenous ZNFX1 protein in cell lines of the patient homozygous for the p.E1606Rfs*10 variant is truncated, whereas ZNFX1 expression is abolished in cell lines from the patients with the p.S959* variant. Lymphocyte subsets are present at normal frequencies in these patients and produce IFN-γ normally. The hematopoietic and nonhematopoietic cells of the patients tested respond normally to IFN-γ. Our results indicate that human ZNFX1 is associated with stress granules and essential for both monocyte homeostasis and protective immunity to mycobacteria.
Assuntos
Antígenos de Neoplasias/genética , Leucocitose/genética , Infecções por Mycobacterium não Tuberculosas/genética , Células A549 , Adolescente , Antígenos de Neoplasias/metabolismo , Células Cultivadas , Criança , Grânulos Citoplasmáticos/metabolismo , Feminino , Células HEK293 , Células HeLa , Homozigoto , Humanos , Lactente , Interferon gama/metabolismo , Leucocitose/patologia , Masculino , Mutação , Infecções por Mycobacterium não Tuberculosas/patologia , Linhagem , Células THP-1 , Adulto JovemRESUMO
Heterozygous in-frame mutations in coding regions of human STAT3 underlie the only known autosomal dominant form of hyper IgE syndrome (AD HIES). About 5% of familial cases remain unexplained. The mutant proteins are loss-of-function and dominant-negative when tested following overproduction in recipient cells. However, the production of mutant proteins has not been detected and quantified in the cells of heterozygous patients. We report a deep intronic heterozygous STAT3 mutation, c.1282-89C>T, in 7 relatives with AD HIES. This mutation creates a new exon in the STAT3 complementary DNA, which, when overexpressed, generates a mutant STAT3 protein (D427ins17) that is loss-of-function and dominant-negative in terms of tyrosine phosphorylation, DNA binding, and transcriptional activity. In immortalized B cells from these patients, the D427ins17 protein was 2 kDa larger and 4-fold less abundant than wild-type STAT3, on mass spectrometry. The patients' primary B and T lymphocytes responded poorly to STAT3-dependent cytokines. These findings are reminiscent of the impaired responses of leukocytes from other patients with AD HIES due to typical STAT3 coding mutations, providing further evidence for the dominance of the mutant intronic allele. These findings highlight the importance of sequencing STAT3 introns in patients with HIES without candidate variants in coding regions and essential splice sites. They also show that AD HIES-causing STAT3 mutant alleles can be dominant-negative even if the encoded protein is produced in significantly smaller amounts than wild-type STAT3.
Assuntos
Proteínas de Ligação a DNA/genética , Síndrome de Job/genética , Sítios de Splice de RNA/genética , Fator de Transcrição STAT3/genética , Adulto , Alelos , Linfócitos B/metabolismo , Linfócitos B/patologia , Pré-Escolar , Éxons/genética , Feminino , Regulação da Expressão Gênica/genética , Heterozigoto , Humanos , Síndrome de Job/patologia , Mutação com Perda de Função/genética , Masculino , Pessoa de Meia-Idade , Linfócitos T/metabolismo , Linfócitos T/patologiaRESUMO
Most members of the Toll-like receptor (TLR) and interleukin-1 receptor (IL-1R) families transduce signals via a canonical pathway involving the MyD88 adapter and the interleukin-1 receptor-associated kinase (IRAK) complex. This complex contains four molecules, including at least two (IRAK-1 and IRAK-4) active kinases. In mice and humans, deficiencies of IRAK-4 or MyD88 abolish most TLR (except for TLR3 and some TLR4) and IL-1R signaling in both leukocytes and fibroblasts. TLR and IL-1R responses are weak but not abolished in mice lacking IRAK-1, whereas the role of IRAK-1 in humans remains unclear. We describe here a boy with X-linked MECP2 deficiency-related syndrome due to a large de novo Xq28 chromosomal deletion encompassing both MECP2 and IRAK1 Like many boys with MECP2 null mutations, this child died very early, at the age of 7 mo. Unlike most IRAK-4- or MyD88-deficient patients, he did not suffer from invasive bacterial diseases during his short life. The IRAK-1 protein was completely absent from the patient's fibroblasts, which responded very poorly to all TLR2/6 (PAM2CSK4, LTA, FSL-1), TLR1/2 (PAM3CSK4), and TLR4 (LPS, MPLA) agonists tested but had almost unimpaired responses to IL-1ß. By contrast, the patient's peripheral blood mononuclear cells responded normally to all TLR1/2, TLR2/6, TLR4, TLR7, and TLR8 (R848) agonists tested, and to IL-1ß. The death of this child precluded long-term evaluations of the clinical consequences of inherited IRAK-1 deficiency. However, these findings suggest that human IRAK-1 is essential downstream from TLRs but not IL-1Rs in fibroblasts, whereas it plays a redundant role downstream from both TLRs and IL-1Rs in leukocytes.
Assuntos
Fibroblastos/metabolismo , Quinases Associadas a Receptores de Interleucina-1/deficiência , Receptores Toll-Like/metabolismo , Deleção Cromossômica , Cromossomos Humanos X/genética , Humanos , Lactente , Quinases Associadas a Receptores de Interleucina-1/genética , Leucócitos/metabolismo , Masculino , Proteína 2 de Ligação a Metil-CpG/genética , Receptores de Interleucina-1/metabolismo , Transdução de Sinais , Receptores Toll-Like/genéticaRESUMO
Cardiospondylocarpofacial (CSCF) syndrome is characterized by growth retardation, dysmorphic facial features, brachydactyly with carpal-tarsal fusion and extensive posterior cervical vertebral synostosis, cardiac septal defects with valve dysplasia, and deafness with inner ear malformations. Whole-exome sequencing identified heterozygous MAP3K7 mutations in six distinct CSCF-affected individuals from four families and ranging in age from 5 to 37 years. MAP3K7 encodes transforming growth factor ß (TGF-ß)-activated kinase 1 (TAK1), which is involved in the mitogen-activated protein kinase (MAPK)-p38 signaling pathway. MAPK-p38 signaling was markedly altered when expression of non-canonical TGF-ß-driven target genes was impaired. These findings support the loss of transcriptional control of the TGF-ß-MAPK-p38 pathway in fibroblasts obtained from affected individuals. Surprisingly, although TAK1 is located at the crossroad of inflammation, immunity, and cancer, this study reports MAP3K7 mutations in a developmental disorder affecting mainly cartilage, bone, and heart.
Assuntos
Ossos do Carpo/anormalidades , Vértebras Cervicais/anormalidades , Perda Auditiva Condutiva/genética , Heterozigoto , MAP Quinase Quinase Quinases/genética , Insuficiência da Valva Mitral/genética , Mutação/genética , Ossos do Tarso/anormalidades , Anormalidades Múltiplas , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Fibroblastos , Regulação da Expressão Gênica , Perda Auditiva Bilateral , Humanos , Interleucina-1beta/metabolismo , Sistema de Sinalização das MAP Quinases , Masculino , Osteosclerose , Síndrome , Fator de Crescimento Transformador beta/metabolismo , Adulto Jovem , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
BACKGROUND: About 10% of pediatric patients with invasive pneumococcal disease (IPD) die from the disease. Some primary immunodeficiencies (PIDs) are known to confer predisposition to IPD. However, a systematic search for these PIDs has never been carried out in children presenting with IPD. METHODS: We prospectively identified pediatric cases of IPD requiring hospitalization between 2005 and 2011 in 28 pediatric wards throughout France. IPD was defined as a positive pneumococcal culture, polymerase chain reaction result, and/or soluble antigen detection at a normally sterile site. The immunological assessment included abdominal ultrasound, whole-blood counts and smears, determinations of plasma immunoglobulin and complement levels, and the evaluation of proinflammatory cytokines. RESULTS: We included 163 children with IPD (male-to-female ratio, 1.3; median age, 13 months). Seventeen children had recurrent IPD. Meningitis was the most frequent type of infection (87%); other infections included pleuropneumonitis, isolated bloodstream infection, osteomyelitis, endocarditis, and mastoiditis. One patient with recurrent meningitis had a congenital cerebrospinal fluid fistula. The results of immunological explorations were abnormal in 26 children (16%), and a PID was identified in 17 patients (10%), including 1 case of MyD88 deficiency, 3 of complement fraction C2 or C3 deficiencies, 1 of isolated congenital asplenia, and 2 of Bruton disease (X-linked agammaglobulinemia). The proportion of PIDs was much higher in children aged >2 years than in younger children (26% vs 3%; P < .001). CONCLUSIONS: Children with IPD should undergo immunological investigations, particularly those aged >2 years, as PIDs may be discovered in up to 26% of cases.
Assuntos
Síndromes de Imunodeficiência/complicações , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/imunologia , Adolescente , Criança , Pré-Escolar , Suscetibilidade a Doenças , Feminino , França , Humanos , Lactente , Masculino , Estudos ProspectivosRESUMO
BACKGROUND: Generalized pustular psoriasis is a life-threatening disease of unknown cause. It is characterized by sudden, repeated episodes of high-grade fever, generalized rash, and disseminated pustules, with hyperleukocytosis and elevated serum levels of C-reactive protein, which may be associated with plaque-type psoriasis. METHODS: We performed homozygosity mapping and direct sequencing in nine Tunisian multiplex families with autosomal recessive generalized pustular psoriasis. We assessed the effect of mutations on protein expression and conformation, stability, and function. RESULTS: We identified significant linkage to an interval of 1.2 megabases on chromosome 2q13-q14.1 and a homozygous missense mutation in IL36RN, encoding an interleukin-36-receptor antagonist (interleukin-36Ra), an antiinflammatory cytokine. This mutation predicts the substitution of a proline residue for leucine at amino acid position 27 (L27P). Homology-based structural modeling of human interleukin-36Ra suggests that the proline at position 27 affects both the stability of interleukin-36Ra and its interaction with its receptor, interleukin-1 receptor-like 2 (interleukin-1 receptor-related protein 2). Biochemical analyses showed that the L27P variant was poorly expressed and less potent than the nonvariant interleukin-36Ra in inhibiting a cytokine-induced response in an interleukin-8 reporter assay, leading to enhanced production of inflammatory cytokines (interleukin-8 in particular) by keratinocytes from the patients. CONCLUSIONS: Aberrant interleukin-36Ra structure and function lead to unregulated secretion of inflammatory cytokines and generalized pustular psoriasis. (Funded by Agence Nationale de la Recherche and Société Française de Dermatologie.).
Assuntos
Interleucina-1/metabolismo , Psoríase/genética , Receptores de Interleucina/antagonistas & inibidores , Feminino , Genes Recessivos , Ligação Genética , Humanos , Interleucina-1/genética , Masculino , Mutação , Linhagem , Transdução de Sinais , Dermatopatias Vesiculobolhosas , TunísiaRESUMO
We studied the distribution of peripheral B-cell subsets in patients deficient for key factors of the TLR-signaling pathways (MyD88, TIRAP/MAL, IL-1 receptor-associated kinase 4 [IRAK-4], TLR3, UNC-93B, TRIF). All TLRs, except TLR3, which signals through the TRIF adaptor, require MyD88 and IRAK-4 to mediate their function. TLR4 and the TLR2 heterodimers (with TLR1, TLR6, and possibly TLR10) require in addition the adaptor TIRAP, whereas UNC-93B is needed for the proper localization of intracellular TLR3, TLR7, TLR8, and TLR9. We found that IgM(+)IgD(+)CD27(+) but not switched B cells were strongly reduced in MyD88-, IRAK-4-, and TIRAP-deficient patients. This defect did not appear to be compensated with age. However, somatic hypermutation of Ig genes and heavy-chain CDR3 size distribution of IgM(+)IgD(+)CD27(+) B cells were not affected in these patients. In contrast, the numbers of IgM(+)IgD(+)CD27(+) B cells were normal in the absence of TLR3, TRIF, and UNC-93B, suggesting that UNC-93B-dependent TLRs, and notably TLR9, are dispensable for the presence of this subset in peripheral blood. Interestingly, TLR10 was found to be expressed at greater levels in IgM(+)IgD(+)CD27(+) compared with switched B cells in healthy patients. Hence, we propose a role for TIRAP-dependent TLRs, possibly TLR10 in particular, in the development and/or maintenance of IgM(+)IgD(+)CD27(+) B cells in humans.
Assuntos
Linfócitos B/imunologia , Imunoglobulina D/imunologia , Imunoglobulina M/imunologia , Quinases Associadas a Receptores de Interleucina-1/genética , Glicoproteínas de Membrana/genética , Proteínas de Membrana Transportadoras/genética , Fator 88 de Diferenciação Mieloide/genética , Receptores de Interleucina-1/genética , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia , Adolescente , Adulto , Linfócitos B/patologia , Criança , Pré-Escolar , Citocinas/imunologia , Humanos , Imunoglobulina D/análise , Imunoglobulina M/análise , Mutação , Receptor 10 Toll-Like/genética , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/análise , Adulto JovemRESUMO
Human interleukin (IL) 1 receptor-associated kinase 4 (IRAK-4) deficiency is a recently discovered primary immunodeficiency that impairs Toll/IL-1R immunity, except for the Toll-like receptor (TLR) 3- and TLR4-interferon (IFN)-alpha/beta pathways. The clinical and immunological phenotype remains largely unknown. We diagnosed up to 28 patients with IRAK-4 deficiency, tested blood TLR responses for individual leukocyte subsets, and TLR responses for multiple cytokines. The patients' peripheral blood mononuclear cells (PBMCs) did not induce the 11 non-IFN cytokines tested upon activation with TLR agonists other than the nonspecific TLR3 agonist poly(I:C). The patients' individual cell subsets from both myeloid (granulocytes, monocytes, monocyte-derived dendritic cells [MDDCs], myeloid DCs [MDCs], and plasmacytoid DCs) and lymphoid (B, T, and NK cells) lineages did not respond to the TLR agonists that stimulated control cells, with the exception of residual responses to poly(I:C) and lipopolysaccharide in MDCs and MDDCs. Most patients (22 out of 28; 79%) suffered from invasive pneumococcal disease, which was often recurrent (13 out of 22; 59%). Other infections were rare, with the exception of severe staphylococcal disease (9 out of 28; 32%). Almost half of the patients died (12 out of 28; 43%). No death and no invasive infection occurred in patients older than 8 and 14 yr, respectively. The IRAK-4-dependent TLRs and IL-1Rs are therefore vital for childhood immunity to pyogenic bacteria, particularly Streptococcus pneumoniae. Conversely, IRAK-4-dependent human TLRs appear to play a redundant role in protective immunity to most infections, at most limited to childhood immunity to some pyogenic bacteria.
Assuntos
Infecções Bacterianas/imunologia , Infecções Bacterianas/metabolismo , Quinases Associadas a Receptores de Interleucina-1/deficiência , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Receptores Toll-Like/metabolismo , Adolescente , Adulto , Infecções Bacterianas/patologia , Diferenciação Celular/imunologia , Células Cultivadas , Criança , Pré-Escolar , Citocinas/biossíntese , Citocinas/metabolismo , Feminino , Regulação da Expressão Gênica , Humanos , Lactente , Quinases Associadas a Receptores de Interleucina-1/genética , Leucócitos/citologia , Leucócitos/imunologia , Leucócitos/metabolismo , Masculino , Mutação/genética , Células Mieloides/imunologia , Células Mieloides/metabolismo , Linhagem , Receptores Toll-Like/agonistasRESUMO
Nuclear factor-κB essential modulator (NEMO), the regulatory subunit of the IκB kinase complex, is a critical component of the NF-κB pathway. Hypomorphic mutations in the X-linked human NEMO gene cause various forms of anhidrotic ectodermal dysplasia with immunodeficiency (EDA-ID). All known X-linked EDA-ID-causing mutations impair NEMO protein expression, folding, or both. We describe here 2 EDA-ID-causing missense mutations that affect the same residue in the CC2-LZ domain (D311N and D311G) that do not impair NEMO production or folding. Structural studies based on pull-down experiments showed a defect in noncovalent interaction with K63-linked and linear polyubiquitin chains for these mutant proteins. Functional studies on the patients' cells showed an impairment of the classic NF-κB signaling pathways after activation of 2 NEMO ubiquitin-binding-dependent receptors, the TNF and IL-1ß receptors, and in the CD40-dependent NF-κB pathway. We report the first human NEMO mutations responsible for X-linked EDA-ID found to affect the polyubiquitin binding of NEMO rather than its expression and folding. These experiments demonstrate that the binding of human NEMO to polyubiquitin is essential for NF-κB activation. They also demonstrate that the normal expression and folding of NEMO do not exclude a pathogenic role for NEMO mutations in patients with EDA-ID.
Assuntos
Displasia Ectodérmica Anidrótica Tipo 1/genética , Quinase I-kappa B/genética , Síndromes de Imunodeficiência/genética , Ubiquitina/metabolismo , Western Blotting , Displasia Ectodérmica Anidrótica Tipo 1/metabolismo , Ativação Enzimática/genética , Feminino , Humanos , Quinase I-kappa B/metabolismo , Síndromes de Imunodeficiência/metabolismo , Masculino , Mutação de Sentido Incorreto , NF-kappa B/metabolismo , Linhagem , Ligação Proteica , Dobramento de Proteína , Transdução de Sinais/genética , Adulto JovemRESUMO
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 , TimoAssuntos
Bactérias/imunologia , Citocinas/imunologia , Fungos/imunologia , Doença Granulomatosa Crônica/imunologia , Inflamação/imunologia , Linhagem Celular , Doença Granulomatosa Crônica/genética , Humanos , Inflamação/genética , Monócitos/imunologia , Mutação/genética , NADPH Oxidases/genética , Neutrófilos/imunologiaRESUMO
The molecular basis of interindividual clinical variability upon infection with Staphylococcus aureus is unclear. We describe patients with haploinsufficiency for the linear deubiquitinase OTULIN, encoded by a gene on chromosome 5p. Patients suffer from episodes of life-threatening necrosis, typically triggered by S. aureus infection. The disorder is phenocopied in patients with the 5p- (Cri-du-Chat) chromosomal deletion syndrome. OTULIN haploinsufficiency causes an accumulation of linear ubiquitin in dermal fibroblasts, but tumor necrosis factor receptor-mediated nuclear factor κB signaling remains intact. Blood leukocyte subsets are unaffected. The OTULIN-dependent accumulation of caveolin-1 in dermal fibroblasts, but not leukocytes, facilitates the cytotoxic damage inflicted by the staphylococcal virulence factor α-toxin. Naturally elicited antibodies against α-toxin contribute to incomplete clinical penetrance. Human OTULIN haploinsufficiency underlies life-threatening staphylococcal disease by disrupting cell-intrinsic immunity to α-toxin in nonleukocytic cells.
Assuntos
Toxinas Bacterianas , Síndrome de Cri-du-Chat , Endopeptidases , Haploinsuficiência , Proteínas Hemolisinas , Infecções Estafilocócicas , Staphylococcus aureus , Toxinas Bacterianas/imunologia , Síndrome de Cri-du-Chat/genética , Síndrome de Cri-du-Chat/imunologia , Endopeptidases/genética , Haploinsuficiência/genética , Haploinsuficiência/imunologia , Proteínas Hemolisinas/imunologia , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunidade Celular/genética , Necrose , Infecções Estafilocócicas/genética , Infecções Estafilocócicas/imunologia , Infecções Estafilocócicas/patologiaRESUMO
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/metabolismoRESUMO
Most patients with autosomal dominant hyper-IgE syndrome (AD-HIES) carry rare heterozygous STAT3 variants. Only six of the 135 in-frame variants reported have been experimentally shown to be dominant negative (DN), and it has been recently suggested that eight out-of-frame variants operate by haploinsufficiency. We experimentally tested these 143 variants, 7 novel out-of-frame variants found in HIES patients, and other STAT3 variants from the general population. Strikingly, all 15 out-of-frame variants were DN via their encoded (1) truncated proteins, (2) neoproteins generated from a translation reinitiation codon, and (3) isoforms from alternative transcripts or a combination thereof. Moreover, 128 of the 135 in-frame variants (95%) were also DN. The patients carrying the seven non-DN STAT3 in-frame variants have not been studied for other genetic etiologies. Finally, none of the variants from the general population tested, including an out-of-frame variant, were DN. Overall, our findings show that heterozygous STAT3 variants, whether in or out of frame, underlie AD-HIES through negative dominance rather than haploinsufficiency.
Assuntos
Genes Dominantes , Síndrome de Job/genética , Mutação/genética , Fator de Transcrição STAT3/genética , Adolescente , Adulto , Alelos , Processamento Alternativo/genética , Criança , Pré-Escolar , Códon sem Sentido/genética , Evolução Molecular , Família , Feminino , Mutação da Fase de Leitura/genética , Genética Populacional , Células HEK293 , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Linhagem , Biossíntese de Proteínas , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
Autosomal dominant (AD) NFKB1 deficiency is thought to be the most common genetic etiology of common variable immunodeficiency (CVID). However, the causal link between NFKB1 variants and CVID has not been demonstrated experimentally and genetically, and there has been insufficient biochemical characterization and enrichment analysis. We show that the cotransfection of NFKB1-deficient HEK293T cells (lacking both p105 and its cleaved form p50) with a κB reporter, NFKB1/p105, and a homodimerization-defective RELA/p65 mutant results in p50:p65 heterodimer-dependent and p65:p65 homodimer-independent transcriptional activation. We found that 59 of the 90 variants in patients with CVID or related conditions were loss of function or hypomorphic. By contrast, 258 of 260 variants in the general population or patients with unrelated conditions were neutral. None of the deleterious variants displayed negative dominance. The enrichment in deleterious NFKB1 variants of patients with CVID was selective and highly significant (P = 2.78 × 10-15). NFKB1 variants disrupting NFKB1/p50 transcriptional activity thus underlie AD CVID by haploinsufficiency, whereas neutral variants in this assay should not be considered causal.
Assuntos
Imunodeficiência de Variável Comum/genética , Subunidade p50 de NF-kappa B/genética , Animais , Células COS , Linhagem Celular , Chlorocebus aethiops , Células HEK293 , Haploinsuficiência/genética , Humanos , NF-kappa B/genética , Fenótipo , Ativação Transcricional/genéticaRESUMO
The pathophysiology of adverse events following programmed cell death protein 1 (PD-1) blockade, including tuberculosis (TB) and autoimmunity, remains poorly characterized. We studied a patient with inherited PD-1 deficiency and TB who died of pulmonary autoimmunity. The patient's leukocytes did not express PD-1 or respond to PD-1-mediated suppression. The patient's lymphocytes produced only small amounts of interferon (IFN)-γ upon mycobacterial stimuli, similarly to patients with inborn errors of IFN-γ production who are vulnerable to TB. This phenotype resulted from a combined depletion of Vδ2+ γδ T, mucosal-associated invariant T and CD56bright natural killer lymphocytes and dysfunction of other T lymphocyte subsets. Moreover, the patient displayed hepatosplenomegaly and an expansion of total, activated and RORγT+ CD4-CD8- double-negative αß T cells, similar to patients with STAT3 gain-of-function mutations who display lymphoproliferative autoimmunity. This phenotype resulted from excessive amounts of STAT3-activating cytokines interleukin (IL)-6 and IL-23 produced by activated T lymphocytes and monocytes, and the STAT3-dependent expression of RORγT by activated T lymphocytes. Our work highlights the indispensable role of human PD-1 in governing both antimycobacterial immunity and self-tolerance, while identifying potentially actionable molecular targets for the diagnostic and therapeutic management of TB and autoimmunity in patients on PD-1 blockade.
Assuntos
Autoimunidade/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Receptor de Morte Celular Programada 1/genética , Fator de Transcrição STAT3/genética , Tuberculose/imunologia , Autoimunidade/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Antígeno CD56/genética , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Criança , Humanos , Inibidores de Checkpoint Imunológico/efeitos adversos , Inibidores de Checkpoint Imunológico/uso terapêutico , Imunoterapia/efeitos adversos , Interleucina-23/genética , Interleucina-6/genética , Linfócitos Intraepiteliais/imunologia , Linfócitos Intraepiteliais/patologia , Masculino , Mycobacterium tuberculosis/patogenicidade , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Neoplasias/mortalidade , Receptor de Morte Celular Programada 1/deficiência , Tuberculose/genética , Tuberculose/mortalidadeRESUMO
Yellow fever virus (YFV) live attenuated vaccine can, in rare cases, cause life-threatening disease, typically in patients with no previous history of severe viral illness. Autosomal recessive (AR) complete IFNAR1 deficiency was reported in one 12-yr-old patient. Here, we studied seven other previously healthy patients aged 13 to 80 yr with unexplained life-threatening YFV vaccine-associated disease. One 13-yr-old patient had AR complete IFNAR2 deficiency. Three other patients vaccinated at the ages of 47, 57, and 64 yr had high titers of circulating auto-Abs against at least 14 of the 17 individual type I IFNs. These antibodies were recently shown to underlie at least 10% of cases of life-threatening COVID-19 pneumonia. The auto-Abs were neutralizing in vitro, blocking the protective effect of IFN-α2 against YFV vaccine strains. AR IFNAR1 or IFNAR2 deficiency and neutralizing auto-Abs against type I IFNs thus accounted for more than half the cases of life-threatening YFV vaccine-associated disease studied here. Previously healthy subjects could be tested for both predispositions before anti-YFV vaccination.
Assuntos
Anticorpos Neutralizantes/imunologia , Autoanticorpos/imunologia , Doenças Autoimunes , COVID-19 , Doenças Genéticas Inatas , Interferon-alfa , Receptor de Interferon alfa e beta , SARS-CoV-2 , Vacina contra Febre Amarela , Vírus da Febre Amarela , Adolescente , Adulto , Idoso , Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , COVID-19/genética , COVID-19/imunologia , Feminino , Doenças Genéticas Inatas/genética , Doenças Genéticas Inatas/imunologia , Células HEK293 , Humanos , Interferon-alfa/genética , Interferon-alfa/imunologia , Masculino , Pessoa de Meia-Idade , Receptor de Interferon alfa e beta/deficiência , Receptor de Interferon alfa e beta/imunologia , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologia , Vacina contra Febre Amarela/efeitos adversos , Vacina contra Febre Amarela/genética , Vacina contra Febre Amarela/imunologia , Vírus da Febre Amarela/genética , Vírus da Febre Amarela/imunologiaRESUMO
Buruli ulcer, caused by Mycobacterium ulcerans and characterized by devastating necrotizing skin lesions, is the third mycobacterial disease worldwide. The role of host genetics in susceptibility to Buruli ulcer has long been suggested. We conduct the first genome-wide association study of Buruli ulcer on a sample of 1524 well characterized patients and controls from rural Benin. Two-stage analyses identify two variants located within LncRNA genes: rs9814705 in ENSG00000240095.1 (P = 2.85 × 10-7; odds ratio = 1.80 [1.43-2.27]), and rs76647377 in LINC01622 (P = 9.85 × 10-8; hazard ratio = 0.41 [0.28-0.60]). Furthermore, we replicate the protective effect of allele G of a missense variant located in ATG16L1, previously shown to decrease bacterial autophagy (rs2241880, P = 0.003; odds ratio = 0.31 [0.14-0.68]). Our results suggest LncRNAs and the autophagy pathway as critical factors in the development of Buruli ulcer.