RESUMEN
Synaptotagmin-1 (Syt1) is a presynaptic calcium sensor with two calcium binding domains, C2A and C2B, that triggers action potential-induced synchronous neurotransmitter release, while suppressing asynchronous and spontaneous release. We identified a de novo missense mutation (P401L) in the C2B domain in a patient with developmental delay and autistic symptoms. Expressing the orthologous mouse mutant (P400L) in cultured Syt1 null mutant neurons revealed a reduction in dendrite outgrowth with a proportional reduction in synapses. This was not observed in single Syt1PL-rescued neurons that received normal synaptic input when cultured in a control network. Patch-clamp recordings showed that spontaneous miniature release events per synapse were increased more than 500% in Syt1PL-rescued neurons, even beyond the increased rates in Syt1 KO neurons. Furthermore, action potential-induced asynchronous release was increased more than 100%, while synchronous release was unaffected. A similar shift to more asynchronous release was observed during train stimulations. These cellular phenotypes were also observed when Syt1PL was overexpressed in wild type neurons. Our findings show that Syt1PL desynchronizes neurotransmission by increasing the readily releasable pool for asynchronous release and reducing the suppression of spontaneous and asynchronous release. Neurons respond to this by shortening their dendrites, possibly to counteract the increased synaptic input. Syt1PL acts in a dominant-negative manner supporting a causative role for the mutation in the heterozygous patient. We propose that the substitution of a rigid proline to a more flexible leucine at the bottom of the C2B domain impairs clamping of release by interfering with Syt1's primary interface with the SNARE complex. This is a novel cellular phenotype, distinct from what was previously found for other SYT1 disease variants, and points to a role for spontaneous and asynchronous release in SYT1-associated neurodevelopmental disorder.
RESUMEN
PURPOSE: Hao-Fountain syndrome (HAFOUS) is a neurodevelopmental disorder caused by pathogenic variants in USP7. HAFOUS is characterized by developmental delay, intellectual disability, speech delay, behavioral abnormalities, autism spectrum disorder, seizures, hypogonadism, and mild dysmorphic features. We investigated the phenotype of 18 participants with HAFOUS and performed DNA methylation (DNAm) analysis, aiming to generate a diagnostic biomarker. Furthermore, we performed comparative analysis with known episignatures to gain more insight into the molecular pathophysiology of HAFOUS. METHODS: We assessed genomic DNAm profiles of 18 individuals with pathogenic variants and variants of uncertain significance (VUS) in USP7 to map and validate a specific episignature. The comparison between the USP7 cohort and 56 rare genetic disorders with earlier reported DNAm episignatures was performed with statistical and functional correlation. RESULTS: We mapped a sensitive and specific DNAm episignature for pathogenic variants in USP7 and utilized this to reclassify the VUS. Comparative epigenomic analysis showed evidence of HAFOUS similarity to a number of other rare genetic episignature disorders. CONCLUSION: We discovered a sensitive and specific DNAm episignature as a robust diagnostic biomarker for HAFOUS that enables VUS reclassification in USP7. We also expand the phenotypic spectrum of 9 new and 5 previously reported individuals with HAFOUS.
Asunto(s)
Anomalías Múltiples , Trastorno del Espectro Autista , Enfermedades del Desarrollo Óseo , Anomalías Craneofaciales , Sordera , Discapacidad Intelectual , Trastornos del Neurodesarrollo , Humanos , Metilación de ADN/genética , Trastorno del Espectro Autista/genética , Peptidasa Específica de Ubiquitina 7/genética , Epigenómica , Discapacidad Intelectual/genética , Discapacidad Intelectual/diagnóstico , Trastornos del Neurodesarrollo/genética , Fenotipo , BiomarcadoresRESUMEN
Heparan sulfate belongs to the group of glycosaminoglycans (GAGs), highly sulfated linear polysaccharides. Heparan sulfate 2-O-sulfotransferase 1 (HS2ST1) is one of several specialized enzymes required for heparan sulfate synthesis and catalyzes the transfer of the sulfate groups to the sugar moiety of heparan sulfate. We report bi-allelic pathogenic variants in HS2ST1 in four individuals from three unrelated families. Affected individuals showed facial dysmorphism with coarse face, upslanted palpebral fissures, broad nasal tip, and wide mouth, developmental delay and/or intellectual disability, corpus callosum agenesis or hypoplasia, flexion contractures, brachydactyly of hands and feet with broad fingertips and toes, and uni- or bilateral renal agenesis in three individuals. HS2ST1 variants cause a reduction in HS2ST1 mRNA and decreased or absent heparan sulfate 2-O-sulfotransferase 1 in two of three fibroblast cell lines derived from affected individuals. The heparan sulfate synthesized by the individual 1 cell line lacks 2-O-sulfated domains but had an increase in N- and 6-O-sulfated domains demonstrating functional impairment of the HS2ST1. As heparan sulfate modulates FGF-mediated signaling, we found a significantly decreased activation of the MAP kinases ERK1/2 in FGF-2-stimulated cell lines of affected individuals that could be restored by addition of heparin, a GAG similar to heparan sulfate. Focal adhesions in FGF-2-stimulated fibroblasts of affected individuals concentrated at the cell periphery. Our data demonstrate that a heparan sulfate synthesis deficit causes a recognizable syndrome and emphasize a role for 2-O-sulfated heparan sulfate in human neuronal, skeletal, and renal development.
Asunto(s)
Huesos/anomalías , Cuerpo Calloso/patología , Discapacidades del Desarrollo/genética , Riñón/anomalías , Sulfotransferasas/genética , Adolescente , Alelos , Biopsia , Niño , Preescolar , Matriz Extracelular/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Salud de la Familia , Femenino , Fibroblastos/metabolismo , Variación Genética , Heparitina Sulfato/metabolismo , Humanos , Ácido Idurónico/farmacología , Recién Nacido , Masculino , Linaje , Fenotipo , Síndrome , Anomalías Urogenitales/genéticaRESUMEN
PURPOSE: In this study we investigate the disease etiology in 12 patients with de novo variants in FAR1 all resulting in an amino acid change at position 480 (p.Arg480Cys/His/Leu). METHODS: Following next-generation sequencing and clinical phenotyping, functional characterization was performed in patients' fibroblasts using FAR1 enzyme analysis, FAR1 immunoblotting/immunofluorescence, and lipidomics. RESULTS: All patients had spastic paraparesis and bilateral congenital/juvenile cataracts, in most combined with speech and gross motor developmental delay and truncal hypotonia. FAR1 deficiency caused by biallelic variants results in defective ether lipid synthesis and plasmalogen deficiency. In contrast, patients' fibroblasts with the de novo FAR1 variants showed elevated plasmalogen levels. Further functional studies in fibroblasts showed that these variants cause a disruption of the plasmalogen-dependent feedback regulation of FAR1 protein levels leading to uncontrolled ether lipid production. CONCLUSION: Heterozygous de novo variants affecting the Arg480 residue of FAR1 lead to an autosomal dominant disorder with a different disease mechanism than that of recessive FAR1 deficiency and a diametrically opposed biochemical phenotype. Our findings show that for patients with spastic paraparesis and bilateral cataracts, FAR1 should be considered as a candidate gene and added to gene panels for hereditary spastic paraplegia, cerebral palsy, and juvenile cataracts.
Asunto(s)
Aldehído Oxidorreductasas/genética , Éteres , Lípidos , Paraplejía Espástica Hereditaria/genética , Humanos , FenotipoRESUMEN
Microdeletions at 5q11.2 are rare. Subjects show a phenotypic spectrum that overlaps CHARGE syndrome and 22q11.2 deletion syndrome. A growing number of subjects present with learning difficulty and/or intellectual disability, immune deficiency, congenital heart malformation, and dysmorphism. DHX29 and IL6ST have been proposed as candidate genes for the development of the major clinical manifestations. We present a new case and narrow down the shortest region of overlap to evaluate possible candidate genes. Our case does not present developmental delay or immune deficiency indicating a reduced penetrance for some of the main clinical manifestations. The shortest region of overlap between subjects with deletions at 5q11.2 is approximately 450 kb (position 54.3-54.7 Mb). The narrowed region comprises 10 protein coding genes, including DHX29. DHX29 is a strong candidate gene for the main features of 5q11.2-microdeletion syndrome; however, our findings suggest a joined impact of several genes as the cause of the syndrome.
Asunto(s)
Anomalías Múltiples/genética , Anemia Macrocítica/genética , Cardiopatías Congénitas/genética , Discapacidad Intelectual/genética , ARN Helicasas/genética , Anomalías Múltiples/fisiopatología , Anemia Macrocítica/fisiopatología , Preescolar , Deleción Cromosómica , Cromosomas Humanos Par 5/genética , Hibridación Genómica Comparativa , Receptor gp130 de Citocinas/genética , Discapacidades del Desarrollo/genética , Discapacidades del Desarrollo/fisiopatología , Facies , Cardiopatías Congénitas/fisiopatología , Humanos , Lactante , Recién Nacido , Discapacidad Intelectual/fisiopatología , Discapacidades para el Aprendizaje/genética , Discapacidades para el Aprendizaje/fisiopatología , Masculino , FenotipoRESUMEN
Lysine-specific demethylase 6B (KDM6B) demethylates trimethylated lysine-27 on histone H3. The methylation and demethylation of histone proteins affects gene expression during development. Pathogenic alterations in histone lysine methylation and demethylation genes have been associated with multiple neurodevelopmental disorders. We have identified a number of de novo alterations in the KDM6B gene via whole exome sequencing (WES) in a cohort of 12 unrelated patients with developmental delay, intellectual disability, dysmorphic facial features, and other clinical findings. Our findings will allow for further investigation in to the role of the KDM6B gene in human neurodevelopmental disorders.
Asunto(s)
Variación Genética , Histona Demetilasas con Dominio de Jumonji/genética , Trastornos del Neurodesarrollo/genética , Adolescente , Preescolar , Estudios de Cohortes , Femenino , Humanos , MasculinoRESUMEN
Simultaneous analysis of multiple genes using next-generation sequencing (NGS) technology has become widely available. Copy-number variations (CNVs) in disease-associated genes have emerged as a cause for several hereditary disorders. CNVs are, however, not routinely detected using NGS analysis. The aim of this study was to assess the diagnostic yield and the prevalence of CNVs using our panel of Hereditary Thoracic Aortic Disease (H-TAD)-associated genes. Eight hundred ten patients suspected of H-TAD were analyzed by targeted NGS analysis of 21 H-TAD associated genes. In addition, the eXome hidden Markov model (XHMM; an algorithm to identify CNVs in targeted NGS data) was used to detect CNVs in these genes. A pathogenic or likely pathogenic variant was found in 66 of 810 patients (8.1%). Of these 66 pathogenic or likely pathogenic variants, six (9.1%) were CNVs not detectable by routine NGS analysis. These CNVs were four intragenic (multi-)exon deletions in MYLK, TGFB2, SMAD3, and PRKG1, respectively. In addition, a large duplication including NOTCH1 and a large deletion encompassing SCARF2 were detected. As confirmed by additional analyses, both CNVs indicated larger chromosomal abnormalities, which could explain the phenotype in both patients. Given the clinical relevance of the identification of a genetic cause, CNV analysis using a method such as XHMM should be incorporated into the clinical diagnostic care for H-TAD patients.
Asunto(s)
Aorta Torácica/patología , Aneurisma de la Aorta Torácica/genética , Enfermedades de la Aorta/genética , Variaciones en el Número de Copia de ADN/genética , Adulto , Aneurisma de la Aorta Torácica/patología , Enfermedades de la Aorta/patología , Aberraciones Cromosómicas , Proteína Quinasa Dependiente de GMP Cíclico Tipo I/genética , Exoma/genética , Femenino , Predisposición Genética a la Enfermedad , Pruebas Genéticas , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Persona de Mediana Edad , Fenotipo , Receptor Notch1/genética , Receptores Depuradores de Clase F/genéticaRESUMEN
Copy number variations associate with different developmental phenotypes and represent a major cause of congenital anomalies of the kidney and urinary tract (CAKUT). Because rare pathogenic copy number variations are often large and contain multiple genes, identification of the underlying genetic drivers has proven to be difficult. Here we studied the role of rare copy number variations in 80 patients from the KIMONO study cohort for which pathogenic mutations in three genes commonly implicated in CAKUT were excluded. In total, 13 known or novel genomic imbalances in 11 of 80 patients were absent or extremely rare in 23,362 population controls. To identify the most likely genetic drivers for the CAKUT phenotype underlying these rare copy number variations, we used a systematic in silico approach based on frequency in a large data set of controls, annotation with publicly available databases for developmental diseases, tolerance and haploinsufficiency scores, and gene expression profile in the developing kidney and urinary tract. Five novel candidate genes for CAKUT were identified that showed specific expression in the human and mouse developing urinary tract. Among these genes, DLG1 and KIF12 are likely novel susceptibility genes for CAKUT in humans. Thus, there is a significant role of genomic imbalance in the determination of kidney developmental phenotypes. Additionally, we defined a systematic strategy to identify genetic drivers underlying rare copy number variations.
RESUMEN
Mutations in COL4A1 have been identified in families with hereditary small vessel disease of the brain presumably due to a dominant-negative mechanism. Here, we report on two novel mutations in COL4A1 in two families with porencephaly, intracerebral hemorrhage and severe white matter disease caused by haploinsufficiency. Two families with various clinical presentations of cerebral microangiopathy and autosomal dominant inheritance were examined. Clinical, neuroradiological and genetic investigations were performed. Electron microscopy of the skin was also performed. In one of the families, sequence analysis revealed a one base deletion, c.2085del, leading to a frameshift and a premature stopcodon, p.(Gly696fs). In the other family, a splice site mutation was identified, c.2194-1G>A, which most likely leads to skipping of an exon with a frameshift and premature termination as a result. In fibroblasts of affected individuals from both the families, nonsense-mediated decay (NMD) of the mutant COL4A1 messenger RNAs (mRNAs) and a clear reduction of COL4A1 protein expression were demonstrated, indicating haploinsufficiency of COL4A1. Moreover, thickening of the capillary basement membrane in the skin was documented, similar to reports in patients with COL4A1 missense mutations. These findings suggest haploinsufficiency, a different mechanism from the commonly assumed dominant-negative effect, for COL4A1 mutations as a cause of (antenatal) intracerebral hemorrhage and white matter disease.
Asunto(s)
Enfermedades de los Pequeños Vasos Cerebrales/genética , Colágeno Tipo IV/genética , Haploinsuficiencia , Mutación , Adulto , Anciano , Secuencia de Bases , Membrana Basal/metabolismo , Encéfalo/patología , Enfermedades de los Pequeños Vasos Cerebrales/diagnóstico , Femenino , Fibroblastos/metabolismo , Fibroblastos/patología , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Linaje , Adulto JovenRESUMEN
BACKGROUND: In children with anorectal malformations (ARM), additional anomalies can occur within the VACTERL-association. Routine screening is of great importance for early identification and potential treatment. However, uniformity in screening protocols is lacking and only small cohorts have been described in literature. The aim of this study was to assess and describe a unique large cohort of ARM patients who underwent VACTERL screening in the neonatal period. METHODS: A retrospective mono-center cohort study was performed. Included were all neonates born between January 2000 and December 2020 who were diagnosed with ARM and screened for additional anomalies. Full screening consisted of x-ray and ultrasound of the spine, cardiac and renal ultrasound, and physical examination for limb deformities, esophageal atresia, and ARM. Criteria for VACTERL-classification were predefined according to the EUROCAT-definitions. RESULTS: In total, 216 patients were included, of whom 167 (77.3%) underwent full VACTERL-screening (66% in 2000-2006 vs. 82% in 2007-2013 vs. 86% in 2014-2020). Median age at follow-up was 7.0 years (IQR 3.0-12.8). In 103/167 patients (61.7%), additional anomalies were identified. Some 35/216 patients (16.2%) fulfilled the criteria of a form of VACTERL-association. In 37/216 patients (17.1%), a genetic cause or syndrome was found. CONCLUSIONS: The majority of ARM patients underwent full screening to detect additional anomalies (77%), which improved over time to 86%. Yet, approximately a quarter of patients was not screened, with the potential of missing important additional anomalies that might have severe consequences in the future. Forms of VACTERL-association or genetic causes were found in 16% and 17% respectively. This study emphasizes the importance of routine screening. LEVEL OF EVIDENCE: III.
Asunto(s)
Malformaciones Anorrectales , Cardiopatías Congénitas , Deformidades Congénitas de las Extremidades , Recién Nacido , Niño , Humanos , Preescolar , Malformaciones Anorrectales/diagnóstico , Malformaciones Anorrectales/epidemiología , Estudios Retrospectivos , Estudios de Cohortes , Esófago/diagnóstico por imagen , Esófago/anomalías , Tráquea/anomalías , Deformidades Congénitas de las Extremidades/diagnóstico por imagen , Deformidades Congénitas de las Extremidades/epidemiología , Cardiopatías Congénitas/diagnóstico , Cardiopatías Congénitas/epidemiología , Riñón/anomalías , Canal Anal/diagnóstico por imagen , Canal Anal/anomalías , Columna Vertebral/diagnóstico por imagen , Columna Vertebral/anomalíasRESUMEN
Pachydermoperiostosis, or primary hypertrophic osteoarthropathy (PHO), is an inherited multisystem disorder, whose features closely mimic the reactive osteoarthropathy that commonly accompanies neoplastic and inflammatory pathologies. We previously described deficiency of the prostaglandin-degrading enzyme 15-hydroxyprostaglandin dehydrogenase (HPGD) as a cause of this condition, implicating elevated circulating prostaglandin E(2) (PGE(2)) as causative of PHO, and perhaps also as the principal mediator of secondary HO. However, PHO is genetically heterogeneous. Here, we use whole-exome sequencing to identify recessive mutations of the prostaglandin transporter SLCO2A1, in individuals lacking HPGD mutations. We performed exome sequencing of four probands with severe PHO, followed by conventional mutation analysis of SLCO2A1 in nine others. Biallelic SLCO2A1 mutations were identified in 12 of the 13 families. Affected individuals had elevated urinary PGE(2), but unlike HPGD-deficient patients, also excreted considerable quantities of the PGE(2) metabolite, PGE-M. Clinical differences between the two groups were also identified, notably that SLCO2A1-deficient individuals have a high frequency of severe anemia due to myelofibrosis. These findings reinforce the key role of systemic or local prostaglandin excess as the stimulus to HO. They also suggest that the induction or maintenance of hematopoietic stem cells by prostaglandin may depend upon transporter activity.
Asunto(s)
Transportadores de Anión Orgánico/genética , Osteoartropatía Hipertrófica Primaria/etiología , Osteoartropatía Hipertrófica Primaria/genética , Mielofibrosis Primaria/genética , Adolescente , Adulto , Niño , Femenino , Predisposición Genética a la Enfermedad , Humanos , Masculino , Mutación , Osteoartropatía Hipertrófica Primaria/metabolismo , Prostaglandinas/metabolismo , Adulto JovenRESUMEN
BACKGROUND: Duodenal obstruction (DO) is a congenital anomaly that is highly associated with other anomalies, such as cardiac anomalies and trisomy 21. However, an overview of additional anomalies and patient-specific risk factors for cardiac anomalies is lacking. Potential association with the vertebral, anorectal, cardiac, trachea-esophageal, renal and limb anomalies (VACTERL) spectrum remains unknown. Therefore, we aim to examine the incidence of associated anomalies, a VACTERL-spectrum association and patient-specific risk factors for cardiac anomalies in patients with DO. METHODS: A retrospective cohort study was performed between 1996 and 2021. Outcomes were the presence of any additional anomalies. Risk factors for cardiac anomalies were analyzed using multivariate logistic regression. RESULTS: Of 112 neonates with DO, 47% (N = 53/112) had one associated anomaly and 38% (N = 20/53) had multiple anomalies. Cardiac anomalies (N = 35/112) and trisomy 21 (N = 35/112) were present in 31%. In four patients, VACTERL-spectrum was discovered, all with cardiac anomalies. Trisomy 21 was found to be a risk factor for cardiac anomalies (OR:6.5; CI-95%2.6-16.1). CONCLUSION: Associated anomalies were present in half of patients with DO, of which cardiac anomalies and trisomy 21 occurred most often, and the VACTERL-spectrum was present in four patients. Trisomy 21 was a significant risk factor for cardiac anomalies. Therefore, we recommend a preoperative echocardiogram in patients with DO. In case a cardiac anomaly is found without trisomy 21, VACTERL-screening should be performed.
RESUMEN
Monozygotic (MZ) twins show remarkable resemblance in many aspects of behavior, health, and disease. Until recently, MZ twins were usually called "genetically identical"; however, evidence for genetic and epigenetic differences within rare MZ twin pairs has accumulated. Here, we summarize the literature on MZ twins discordant for Mendelian inherited disorders and chromosomal abnormalities. A systematic literature search for English articles on discordant MZ twin pairs was performed in Web of Science and PubMed. A total number of 2,016 publications were retrieved and reviewed and 439 reports were retained. Discordant MZ twin pairs are informative in respect to variability of phenotypic expression, pathogenetic mechanisms, epigenetics, and post-zygotic mutagenesis and may serve as a model for research on genetic defects. The analysis of single discordant MZ twin pairs may represent an elegant approach to identify genes in inherited disorders.
Asunto(s)
Trastornos de los Cromosomas/genética , Enfermedades en Gemelos/genética , Investigación Genética , Estudios en Gemelos como Asunto , Gemelos Monocigóticos/genética , Epigenómica , Femenino , Humanos , Masculino , FenotipoRESUMEN
PURPOSE: Current clinical classifications do not distinguish between the severity of the MICrophthalmia/Anophthalmia (MICA) spectrum with regard to treatment urgency. We aim to provide parameters for distinguishing mild, moderate and severe MICA using clinical and biometrical characteristics. METHODS: We performed a single-centre, cross-sectional analysis of prospective cohort of 58 MICA children from September 2013 to February 2018 seen at the Amsterdam University Medical Center, The Netherlands. All patients with a visible underdeveloped globe were included. We performed full ophthalmic evaluation including horizontal palpebral fissure length, axial length by ultrasound and/or MRI measurements, paediatric and genetic evaluation. Cases were subdivided based on clinical characteristics. Biometrical data were used to calculate the relative axial length (rAL) and the relative horizontal palpebral fissure length (rHPF) compared with the healthy contralateral eye for unilateral cases. RESULTS: In previously untreated patients, a strong correlation exists between rAL and rHPF, distinguishing between severe, moderate and mild subjects using rAL of 0-45%, 45-75% and 75%-100%, respectively. Clinical subgroups were randomly dispersed throughout the scatterplot. CONCLUSION: Current classifications lack clinical implications for MICA patients. We suggest measuring eyelid length and axial length to classify the severity and determine treatment strategy. The 'severe' group has obvious asymmetry and abnormal socket configuration for which therapy should quickly be initiated; the 'moderately' affected group has normal socket anatomy with a microphthalmic eye with disturbing asymmetry for which treatment should be initiated within months of development; the 'mild' group has a slightly smaller axial length or less obvious eyelid asymmetry for which reconstructive correction is possible, but expansive conformer treatment is unnecessary.
RESUMEN
KIF21B is a kinesin protein that promotes intracellular transport and controls microtubule dynamics. We report three missense variants and one duplication in KIF21B in individuals with neurodevelopmental disorders associated with brain malformations, including corpus callosum agenesis (ACC) and microcephaly. We demonstrate, in vivo, that the expression of KIF21B missense variants specifically recapitulates patients' neurodevelopmental abnormalities, including microcephaly and reduced intra- and inter-hemispheric connectivity. We establish that missense KIF21B variants impede neuronal migration through attenuation of kinesin autoinhibition leading to aberrant KIF21B motility activity. We also show that the ACC-related KIF21B variant independently perturbs axonal growth and ipsilateral axon branching through two distinct mechanisms, both leading to deregulation of canonical kinesin motor activity. The duplication introduces a premature termination codon leading to nonsense-mediated mRNA decay. Although we demonstrate that Kif21b haploinsufficiency leads to an impaired neuronal positioning, the duplication variant might not be pathogenic. Altogether, our data indicate that impaired KIF21B autoregulation and function play a critical role in the pathogenicity of human neurodevelopmental disorder.
Asunto(s)
Cinesinas/genética , Actividad Motora , Mutación/genética , Trastornos del Neurodesarrollo/genética , Trastornos del Neurodesarrollo/fisiopatología , Animales , Axones/metabolismo , Movimiento Celular , Proliferación Celular , Corteza Cerebral/embriología , Corteza Cerebral/patología , Corteza Cerebral/fisiopatología , Femenino , Regulación del Desarrollo de la Expresión Génica , Células HEK293 , Humanos , Masculino , Ratones , Mutación Missense/genética , Red Nerviosa/patología , Red Nerviosa/fisiopatología , Neuronas/metabolismo , Tamaño de los Órganos , Organogénesis/genética , Linaje , ARN Mensajero/genética , ARN Mensajero/metabolismo , Pez Cebra/anatomía & histología , Pez Cebra/genéticaRESUMEN
CXCL5 (epithelial-cell-derived neutrophil-activating protein (ENA-)78) is a CXC-chemokine that specifically acts on neutrophils. To obtain insight into the extent of local presence and action of CXCL5 during bacterial meningitis, we measured its concentrations in cerebrospinal fluid (CSF) of patients with culture-proven bacterial meningitis (n=14), aseptic meningitis (n=6), and controls (n=32) and compared these results with levels of other CXC-chemokines, CXCL8- (interleukin-8) and CXCL1-related oncogene (growth-related oncogene (GRO)-alpha). Patients with bacterial meningitis had profoundly elevated CSF concentrations of all three chemokines. CXCL5 was not detectable in patients with aseptic meningitis or control subjects. CSF from patients with bacterial meningitis exerted chemotactic activity towards neutrophils, which was partially inhibited by neutralizing antibodies against CXCL5 and CXCL8, but not CXCL1. CSF from controls exerted minor chemotactic activity, which could be strongly enhanced by the addition of recombinant CXCL5, CXCL8 or CXCL1. During bacterial meningitis, CXCL5 is elevated in CSF, where it is involved in the recruitment of neutrophils to the central nervous system.
Asunto(s)
Interleucina-8/líquido cefalorraquídeo , Interleucina-8/fisiología , Meningitis Bacterianas/líquido cefalorraquídeo , Adolescente , Quimiocina CXCL1 , Quimiocina CXCL5 , Quimiocinas CXC/líquido cefalorraquídeo , Quimiocinas CXC/fisiología , Quimiotaxis de Leucocito/inmunología , Niño , Humanos , Péptidos y Proteínas de Señalización Intercelular/líquido cefalorraquídeo , Péptidos y Proteínas de Señalización Intercelular/fisiología , Interleucina-8/análogos & derivados , Infecciones por Klebsiella/líquido cefalorraquídeo , Infecciones por Klebsiella/inmunología , Meningitis Aséptica/líquido cefalorraquídeo , Meningitis Aséptica/inmunología , Meningitis Bacterianas/inmunología , Meningitis Meningocócica/líquido cefalorraquídeo , Meningitis Meningocócica/inmunología , Meningitis Neumocócica/líquido cefalorraquídeo , Meningitis Neumocócica/inmunología , Activación Neutrófila/inmunologíaRESUMEN
To determine the role of endogenous interleukin-18 (IL-18) in pneumococcal meningitis, meningitis was induced in IL-18 gene-deficient (IL-18(-/-)) and wild-type (WT) mice by intranasal inoculation of Streptococcus pneumoniae with hyaluronidase. Induction of meningitis resulted in an upregulation of both pro- and mature IL-18 in brain tissue in WT mice. IL-18(-/-) and WT mice were equally susceptible to develop meningitis after intranasal infection, yet IL-18(-/-) mice showed a prolonged survival and a suppressed inflammatory response, as reflected by a less profound inflammatory infiltrate around the meninges and lower concentrations of cytokines and chemokines in brain tissue. These findings suggest that endogenous IL-18 contributes to a detrimental inflammatory response during pneumococcal meningitis and that elimination of IL-18 may improve the outcome of this disease.
Asunto(s)
Adyuvantes Inmunológicos/deficiencia , Adyuvantes Inmunológicos/genética , Regulación hacia Abajo/inmunología , Interleucina-18/deficiencia , Interleucina-18/genética , Meningitis Neumocócica/genética , Meningitis Neumocócica/inmunología , Regulación hacia Arriba/inmunología , Adyuvantes Inmunológicos/biosíntesis , Adyuvantes Inmunológicos/fisiología , Animales , Encéfalo/patología , Movimiento Celular/genética , Movimiento Celular/inmunología , Líquido Cefalorraquídeo/citología , Quimiocinas/metabolismo , Recuento de Colonia Microbiana , Citocinas/metabolismo , Regulación hacia Abajo/genética , Inmunidad Innata/genética , Interleucina-18/biosíntesis , Interleucina-18/fisiología , Leucocitos/patología , Meningitis Neumocócica/microbiología , Meningitis Neumocócica/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Streptococcus pneumoniae/crecimiento & desarrollo , Streptococcus pneumoniae/inmunología , Tasa de Supervivencia , Regulación hacia Arriba/genéticaRESUMEN
Intracisternal injection of the CXC-chemokines KC or macrophage inflammatory protein (MIP)-2 induced a pleocytosis in the cerebrospinal fluid (CSF) of rats in a dose dependent way. MIP-2 was much more potent than KC. The concurrent injection of both chemokines revealed a profound synergistic effect on leukocyte recruitment into CSF.