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1.
Nat Immunol ; 23(4): 543-555, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35288714

RESUMO

Despite the success of the BNT162b2 mRNA vaccine, the immunological mechanisms that underlie its efficacy are poorly understood. Here we analyzed the innate and adaptive responses to BNT162b2 in mice, and show that immunization stimulated potent antibody and antigen-specific T cell responses, as well as strikingly enhanced innate responses after secondary immunization, which was concurrent with enhanced serum interferon (IFN)-γ levels 1 d following secondary immunization. Notably, we found that natural killer cells and CD8+ T cells in the draining lymph nodes are the major producers of this circulating IFN-γ. Analysis of knockout mice revealed that induction of antibody and T cell responses to BNT162b2 was not dependent on signaling via Toll-like receptors 2, 3, 4, 5 and 7 nor inflammasome activation, nor the necroptosis or pyroptosis cell death pathways. Rather, the CD8+ T cell response induced by BNT162b2 was dependent on type I interferon-dependent MDA5 signaling. These results provide insights into the molecular mechanisms by which the BNT162b2 vaccine stimulates immune responses.


Assuntos
Linfócitos T CD8-Positivos , Vacinas , Imunidade Adaptativa , Animais , Vacina BNT162 , Humanos , Imunidade Inata , Camundongos , Vacinas Sintéticas , Vacinas de mRNA
2.
Nat Chem Biol ; 20(8): 1012-1021, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38225471

RESUMO

A major challenge in creating universal influenza vaccines is to focus immune responses away from the immunodominant, variable head region of hemagglutinin (HA-head) and toward the evolutionarily conserved stem region (HA-stem). Here we introduce an approach to control antigen orientation via site-specific insertion of aspartate residues that facilitates antigen binding to alum. We demonstrate the generalizability of this approach with antigens from Ebola, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and influenza viruses and observe enhanced neutralizing antibody responses in all cases. We then reorient an H2 HA in an 'upside-down' configuration to increase the exposure and immunogenicity of HA-stem. The reoriented H2 HA (reoH2HA) on alum induced stem-directed antibodies that cross-react with both group 1 and group 2 influenza A subtypes. Electron microscopy polyclonal epitope mapping (EMPEM) revealed that reoH2HA (group 1) elicits cross-reactive antibodies targeting group 2 HA-stems. Our results highlight antigen reorientation as a generalizable approach for designing epitope-focused vaccines.


Assuntos
Vacinas contra Influenza , SARS-CoV-2 , Vacinas contra Influenza/imunologia , Vacinas contra Influenza/química , Humanos , SARS-CoV-2/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Antígenos Virais/imunologia , Antígenos Virais/química , Reações Cruzadas/imunologia , Camundongos , Epitopos/imunologia , Epitopos/química , COVID-19/imunologia , COVID-19/prevenção & controle , COVID-19/virologia , Ebolavirus/imunologia , Vírus da Influenza A/imunologia , Compostos de Alúmen/química , Mapeamento de Epitopos , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/química
3.
Nat Chem Biol ; 18(11): 1270-1276, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36076082

RESUMO

Omicron and its subvariants have rendered most authorized monoclonal antibody-based treatments for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ineffective, highlighting the need for biologics capable of overcoming SARS-CoV-2 evolution. These mostly ineffective antibodies target variable epitopes. Here we describe broad-spectrum SARS-CoV-2 inhibitors developed by tethering the SARS-CoV-2 receptor, angiotensin-converting enzyme 2 (ACE2), to known non-neutralizing antibodies that target highly conserved epitopes in the viral spike protein. These inhibitors, called receptor-blocking conserved non-neutralizing antibodies (ReconnAbs), potently neutralize all SARS-CoV-2 variants of concern (VOCs), including Omicron. Neutralization potency is lost when the linker joining the binding and inhibitory ReconnAb components is severed. In addition, a bi-functional ReconnAb, made by linking ACE2 to a bi-specific antibody targeting two non-overlapping conserved epitopes, defined here, shows sub-nanomolar neutralizing activity against all VOCs, including Omicron and BA.2. Given their conserved targets and modular nature, ReconnAbs have the potential to act as broad-spectrum therapeutics against SARS-CoV-2 and other emerging pandemic diseases.


Assuntos
Produtos Biológicos , Tratamento Farmacológico da COVID-19 , Humanos , Enzima de Conversão de Angiotensina 2 , SARS-CoV-2 , Anticorpos Neutralizantes , Glicoproteína da Espícula de Coronavírus/metabolismo , Anticorpos Antivirais/metabolismo , Peptidil Dipeptidase A/metabolismo , Epitopos , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico
4.
PLoS Genet ; 17(11): e1009881, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34780472

RESUMO

Many tissue-specific stem cells maintain the ability to produce multiple cell types during long periods of non-division, or quiescence. FOXO transcription factors promote quiescence and stem cell maintenance, but the mechanisms by which FOXO proteins promote multipotency during quiescence are still emerging. The single FOXO ortholog in C. elegans, daf-16, promotes entry into a quiescent and stress-resistant larval stage called dauer in response to adverse environmental cues. During dauer, stem and progenitor cells maintain or re-establish multipotency to allow normal development to resume after dauer. We find that during dauer, daf-16/FOXO prevents epidermal stem cells (seam cells) from prematurely adopting differentiated, adult characteristics. In particular, dauer larvae that lack daf-16 misexpress collagens that are normally adult-enriched. Using col-19p::gfp as an adult cell fate marker, we find that all major daf-16 isoforms contribute to opposing col-19p::gfp expression during dauer. By contrast, daf-16(0) larvae that undergo non-dauer development do not misexpress col-19p::gfp. Adult cell fate and the timing of col-19p::gfp expression are regulated by the heterochronic gene network, including lin-41 and lin-29. lin-41 encodes an RNA-binding protein orthologous to LIN41/TRIM71 in mammals, and lin-29 encodes a conserved zinc finger transcription factor. In non-dauer development, lin-41 opposes adult cell fate by inhibiting the translation of lin-29, which directly activates col-19 transcription and promotes adult cell fate. We find that during dauer, lin-41 blocks col-19p::gfp expression, but surprisingly, lin-29 is not required in this context. Additionally, daf-16 promotes the expression of lin-41 in dauer larvae. The col-19p::gfp misexpression phenotype observed in dauer larvae with reduced daf-16 requires the downregulation of lin-41, but does not require lin-29. Taken together, this work demonstrates a novel role for daf-16/FOXO as a heterochronic gene that promotes expression of lin-41/TRIM71 to contribute to multipotent cell fate in a quiescent stem cell model.


Assuntos
Proteínas de Caenorhabditis elegans/fisiologia , Caenorhabditis elegans/citologia , Linhagem da Célula , Fatores de Transcrição Forkhead/fisiologia , Fatores de Transcrição/fisiologia , Animais , Caenorhabditis elegans/crescimento & desenvolvimento , Proteínas de Caenorhabditis elegans/genética , Colágeno/metabolismo , Fatores de Transcrição Forkhead/genética , Larva/citologia , Larva/metabolismo , Fatores de Transcrição/genética
5.
Artigo em Inglês | MEDLINE | ID: mdl-37917480

RESUMO

OBJECTIVES: The increasing accessibility of DNA ancestry information may influence perceptions of others' and one's own racial identity. The current work tested whether the presence of genetic testing information influenced Black participants' perceptions of individuals who claim a mismatched racial identity (i.e., a racial identity that differs from their parents), and whether these perceptions are moderated by the amount of corroborating DNA evidence and racial claim of the target. METHOD: Black participants (N = 1,041) were randomly assigned to read about an individual claiming a Black or White mismatched racial identity. The target either had a majority amount (71%) of corroborating genetic information, a minimal amount (29%) or made no mention of genetic information. RESULTS: When a majority percentage of corroborating genetic information was provided, participants evaluated Black-identified targets more favorably than White-identified targets. Additionally, Black-identified targets were evaluated most favorably when they had a majority amount of corroborating genetic information. CONCLUSIONS: Among Black perceivers, a majority amount of corroborating genetic information increased positive evaluations of a mismatched, Black-identified racial claim. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

6.
Int J Mol Sci ; 24(19)2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37834023

RESUMO

The ACTN2 gene encodes α-actinin 2, located in the Z-disc of the sarcomeres in striated muscle. In this study, we sought to investigate the effects of an ACTN2 missense variant of unknown significance (p.A868T) on cardiac muscle structure and function. Left ventricular free wall samples were obtained at the time of cardiac transplantation from a heart failure patient with the ACTN2 A868T heterozygous variant. This variant is in the EF 3-4 domain known to interact with titin and α-actinin. At the ultrastructural level, ACTN2 A868T cardiac samples presented small structural changes in cardiomyocytes when compared to healthy donor samples. However, contractile mechanics of permeabilized ACTN2 A868T variant cardiac tissue displayed higher myofilament Ca2+ sensitivity of isometric force, reduced sinusoidal stiffness, and faster rates of tension redevelopment at all Ca2+ levels. Small-angle X-ray diffraction indicated increased separation between thick and thin filaments, possibly contributing to changes in muscle kinetics. Molecular dynamics simulations indicated that while the mutation does not significantly impact the structure of α-actinin on its own, it likely alters the conformation associated with titin binding. Our results can be explained by two Z-disc mediated communication pathways: one pathway that involves α-actinin's interaction with actin, affecting thin filament regulation, and the other pathway that involves α-actinin's interaction with titin, affecting thick filament activation. This work establishes the role of α-actinin 2 in modulating cross-bridge kinetics and force development in the human myocardium as well as how it can be involved in the development of cardiac disease.


Assuntos
Actinina , Miofibrilas , Humanos , Actinina/genética , Actinina/metabolismo , Conectina/genética , Conectina/metabolismo , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Miofibrilas/metabolismo , Sarcômeros/metabolismo
7.
Nat Chem Biol ; 16(12): 1376-1384, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32807964

RESUMO

Currently approved immune checkpoint inhibitor therapies targeting the PD-1 and CTLA-4 receptor pathways are powerful treatment options for certain cancers; however, most patients across cancer types still fail to respond. Consequently, there is interest in discovering and blocking alternative pathways that mediate immune suppression. One such mechanism is an upregulation of sialoglycans in malignancy, which has been recently shown to inhibit immune cell activation through multiple mechanisms and therefore represents a targetable glycoimmune checkpoint. Since these glycans are not canonically druggable, we designed an αHER2 antibody-sialidase conjugate that potently and selectively strips diverse sialoglycans from breast cancer cells. In syngeneic breast cancer models, desialylation enhanced immune cell infiltration and activation and prolonged the survival of mice, an effect that was dependent on expression of the Siglec-E checkpoint receptor found on tumor-infiltrating myeloid cells. Thus, antibody-sialidase conjugates represent a promising modality for glycoimmune checkpoint therapy.


Assuntos
Imunoterapia/métodos , Melanoma Experimental/terapia , Neuraminidase/imunologia , Polissacarídeos/química , Receptor ErbB-2/química , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico/imunologia , Aloenxertos , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/metabolismo , Antígeno B7-H1/genética , Antígeno B7-H1/imunologia , Linhagem Celular Tumoral , Humanos , Hidrólise , Imunoconjugados/química , Imunoconjugados/metabolismo , Imunoconjugados/farmacologia , Células Matadoras Naturais/citologia , Células Matadoras Naturais/imunologia , Melanoma Experimental/genética , Melanoma Experimental/imunologia , Melanoma Experimental/mortalidade , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Moleculares , Terapia de Alvo Molecular , Neuraminidase/química , Neuraminidase/genética , Polissacarídeos/imunologia , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/imunologia , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Estrutura Secundária de Proteína , Receptor ErbB-2/genética , Receptor ErbB-2/imunologia , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico/química , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico/genética , Análise de Sobrevida , Linfócitos T/citologia , Linfócitos T/imunologia
8.
Proc Natl Acad Sci U S A ; 116(20): 9947-9952, 2019 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31028143

RESUMO

In creating vaccines against infectious agents, there is often a desire to direct an immune response toward a particular conformational epitope on an antigen. We present a method, called protect, modify, deprotect (PMD), to generate immunogenic proteins aimed to direct a vaccine-induced antibody (Ab) response toward an epitope defined by a specific monoclonal Ab (mAb). The mAb is used to protect the target epitope on the protein. Then the remaining exposed surfaces of the protein are modified to render them nonimmunogenic. Finally, the epitope is deprotected by removal of the mAb. The resultant protein is modified at surfaces other than the target epitope. We validate PMD using a well-characterized antigen, hen egg white lysozyme, then demonstrate the utility of PMD using influenza virus hemagglutinin (HA). We use an mAb to protect a highly conserved epitope on the stem domain of HA. Exposed surface amines are then modified with short polyethylene glycol chains. The resultant antigen shows markedly reduced binding to mAbs that target the head region of HA, while maintaining binding to mAbs at the epitope of interest. This antigenic preference is also observed with yeast cells displaying Ab fragments. Antisera from guinea pigs immunized with the PMD-modified HA show increased cross-reactivity with HAs from other influenza strains, compared with antisera obtained with unmodified HA trimers. PMD has the potential to direct an Ab response at high resolution and could be used in combination with other such strategies. There are many attractive targets for the application of PMD.


Assuntos
Epitopos/imunologia , Imunogenicidade da Vacina , Vacinas/imunologia , Animais , Anticorpos Monoclonais , Cobaias , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Muramidase/imunologia
9.
J Nutr ; 151(5): 1139-1149, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33693900

RESUMO

BACKGROUND: Fructose consumption has been linked to nonalcoholic fatty liver disease (NAFLD) in children. However, the effect of high-fructose corn syrup (HFCS) compared with sucrose in pediatric NAFLD has not been investigated. OBJECTIVES: We tested whether the isocaloric substitution of dietary sucrose by HFCS would increase the severity of NAFLD in juvenile pigs, and whether this effect would be associated with changes in gut histology, SCFA production, and microbial diversity. METHODS: Iberian pigs, 53-d-old and pair-housed in pens balanced for weight and sex, were randomly assigned to receive a mash diet top-dressed with increasing amounts of sucrose (SUC; n = 3 pens; 281.6-486.8 g/kg diet) or HFCS (n = 4; 444.3-724.8 g/kg diet) during 16 wk. Diets exceeded the animal's energy requirements by providing sugars in excess, but met the requirements for all other nutrients. Animals were killed at 165 d of age after blood sampling, and liver, muscle, and gut were collected for histology, metabolome, and microbiome analyses. Data were analyzed by multivariate and univariate statistics. RESULTS: Compared with SUC, HFCS increased subcutaneous fat, triacylglycerides in plasma, and butyrate in colon (P ≤ 0.05). In addition, HFCS decreased UMP and short-chain acyl carnitines in liver, and urea nitrogen and creatinine in serum (P ≤ 0.05). Microbiome analysis showed a 24.8% average dissimilarity between HFCS and SUC associated with changes in SCFA-producing bacteria. Body weight gain, intramuscular fat, histological and serum markers of liver injury, and circulating hormones, glucose, and proinflammatory cytokines did not differ between diets. CONCLUSIONS: Fructose consumption derived from HFCS promoted butyrate synthesis, triglyceridemia, and subcutaneous lipid deposition in juvenile Iberian pigs, but did not increase serum and histological markers of NAFLD compared with a sucrose-enriched diet. Longer studies could be needed to observe differences in liver injury among sugar types.


Assuntos
Adiposidade/efeitos dos fármacos , Sacarose Alimentar/efeitos adversos , Xarope de Milho Rico em Frutose/efeitos adversos , Hepatopatia Gordurosa não Alcoólica/etiologia , Triglicerídeos/sangue , Animais , Sacarose Alimentar/administração & dosagem , Ácidos Graxos Voláteis/metabolismo , Feminino , Microbioma Gastrointestinal , Trato Gastrointestinal/anatomia & histologia , Trato Gastrointestinal/efeitos dos fármacos , Xarope de Milho Rico em Frutose/administração & dosagem , Masculino , Distribuição Aleatória , Suínos
11.
Mol Psychiatry ; 22(3): 336-345, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28093568

RESUMO

The complex nature of human cognition has resulted in cognitive genomics lagging behind many other fields in terms of gene discovery using genome-wide association study (GWAS) methods. In an attempt to overcome these barriers, the current study utilized GWAS meta-analysis to examine the association of common genetic variation (~8M single-nucleotide polymorphisms (SNP) with minor allele frequency ⩾1%) to general cognitive function in a sample of 35 298 healthy individuals of European ancestry across 24 cohorts in the Cognitive Genomics Consortium (COGENT). In addition, we utilized individual SNP lookups and polygenic score analyses to identify genetic overlap with other relevant neurobehavioral phenotypes. Our primary GWAS meta-analysis identified two novel SNP loci (top SNPs: rs76114856 in the CENPO gene on chromosome 2 and rs6669072 near LOC105378853 on chromosome 1) associated with cognitive performance at the genome-wide significance level (P<5 × 10-8). Gene-based analysis identified an additional three Bonferroni-corrected significant loci at chromosomes 17q21.31, 17p13.1 and 1p13.3. Altogether, common variation across the genome resulted in a conservatively estimated SNP heritability of 21.5% (s.e.=0.01%) for general cognitive function. Integration with prior GWAS of cognitive performance and educational attainment yielded several additional significant loci. Finally, we found robust polygenic correlations between cognitive performance and educational attainment, several psychiatric disorders, birth length/weight and smoking behavior, as well as a novel genetic association to the personality trait of openness. These data provide new insight into the genetics of neurocognitive function with relevance to understanding the pathophysiology of neuropsychiatric illness.


Assuntos
Cognição/fisiologia , Transtornos Neurocognitivos/genética , Adulto , Alelos , Feminino , Frequência do Gene/genética , Estudos de Associação Genética/métodos , Loci Gênicos/genética , Predisposição Genética para Doença/genética , Variação Genética/genética , Estudo de Associação Genômica Ampla/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Herança Multifatorial/genética , Polimorfismo de Nucleotídeo Único/genética , População Branca/genética
12.
Mol Psychiatry ; 21(6): 837-43, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26390830

RESUMO

Inbreeding depression refers to lower fitness among offspring of genetic relatives. This reduced fitness is caused by the inheritance of two identical chromosomal segments (autozygosity) across the genome, which may expose the effects of (partially) recessive deleterious mutations. Even among outbred populations, autozygosity can occur to varying degrees due to cryptic relatedness between parents. Using dense genome-wide single-nucleotide polymorphism (SNP) data, we examined the degree to which autozygosity associated with measured cognitive ability in an unselected sample of 4854 participants of European ancestry. We used runs of homozygosity-multiple homozygous SNPs in a row-to estimate autozygous tracts across the genome. We found that increased levels of autozygosity predicted lower general cognitive ability, and estimate a drop of 0.6 s.d. among the offspring of first cousins (P=0.003-0.02 depending on the model). This effect came predominantly from long and rare autozygous tracts, which theory predicts as more likely to be deleterious than short and common tracts. Association mapping of autozygous tracts did not reveal any specific regions that were predictive beyond chance after correcting for multiple testing genome wide. The observed effect size is consistent with studies of cognitive decline among offspring of known consanguineous relationships. These findings suggest a role for multiple recessive or partially recessive alleles in general cognitive ability, and that alleles decreasing general cognitive ability have been selected against over evolutionary time.


Assuntos
Cognição/fisiologia , Depressão por Endogamia/genética , Adulto , Alelos , Mapeamento Cromossômico/métodos , Feminino , Genoma Humano/genética , Estudo de Associação Genômica Ampla , Homozigoto , Humanos , Depressão por Endogamia/fisiologia , Masculino , Polimorfismo de Nucleotídeo Único/genética , População Branca/genética
13.
Intelligence ; 54: 80-89, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26912939

RESUMO

Two themes are emerging regarding the molecular genetic aetiology of intelligence. The first is that intelligence is influenced by many variants and those that are tagged by common single nucleotide polymorphisms account for around 30% of the phenotypic variation. The second, in line with other polygenic traits such as height and schizophrenia, is that these variants are not randomly distributed across the genome but cluster in genes that work together. Less clear is whether the very low range of cognitive ability (intellectual disability) is simply one end of the normal distribution describing individual differences in cognitive ability across a population. Here, we examined 40 genes with a known association with non-syndromic autosomal recessive intellectual disability (NS-ARID) to determine if they are enriched for common variants associated with the normal range of intelligence differences. The current study used the 3511 individuals of the Cognitive Ageing Genetics in England and Scotland (CAGES) consortium. In addition, a text mining analysis was used to identify gene sets biologically related to the NS-ARID set. Gene-based tests indicated that genes implicated in NS-ARID were not significantly enriched for quantitative trait loci (QTL) associated with intelligence. These findings suggest that genes in which mutations can have a large and deleterious effect on intelligence are not associated with variation across the range of intelligence differences.

14.
Mol Psychiatry ; 19(1): 76-87, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23207651

RESUMO

Cognitive decline is a feared aspect of growing old. It is a major contributor to lower quality of life and loss of independence in old age. We investigated the genetic contribution to individual differences in nonpathological cognitive ageing in five cohorts of older adults. We undertook a genome-wide association analysis using 549 692 single-nucleotide polymorphisms (SNPs) in 3511 unrelated adults in the Cognitive Ageing Genetics in England and Scotland (CAGES) project. These individuals have detailed longitudinal cognitive data from which phenotypes measuring each individual's cognitive changes were constructed. One SNP--rs2075650, located in TOMM40 (translocase of the outer mitochondrial membrane 40 homolog)--had a genome-wide significant association with cognitive ageing (P=2.5 × 10(-8)). This result was replicated in a meta-analysis of three independent Swedish cohorts (P=2.41 × 10(-6)). An Apolipoprotein E (APOE) haplotype (adjacent to TOMM40), previously associated with cognitive ageing, had a significant effect on cognitive ageing in the CAGES sample (P=2.18 × 10(-8); females, P=1.66 × 10(-11); males, P=0.01). Fine SNP mapping of the TOMM40/APOE region identified both APOE (rs429358; P=3.66 × 10(-11)) and TOMM40 (rs11556505; P=2.45 × 10(-8)) as loci that were associated with cognitive ageing. Imputation and conditional analyses in the discovery and replication cohorts strongly suggest that this effect is due to APOE (rs429358). Functional genomic analysis indicated that SNPs in the TOMM40/APOE region have a functional, regulatory non-protein-coding effect. The APOE region is significantly associated with nonpathological cognitive ageing. The identity and mechanism of one or multiple causal variants remain unclear.


Assuntos
Envelhecimento/genética , Apolipoproteínas E/genética , Cognição/fisiologia , Polimorfismo de Nucleotídeo Único/genética , Estudos de Coortes , Inglaterra , Feminino , Frequência do Gene , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Desequilíbrio de Ligação , Masculino , Proteínas de Membrana Transportadoras/genética , Proteínas do Complexo de Importação de Proteína Precursora Mitocondrial , Escócia
15.
Mol Psychiatry ; 19(2): 168-74, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24342994

RESUMO

It has long been recognized that generalized deficits in cognitive ability represent a core component of schizophrenia (SCZ), evident before full illness onset and independent of medication. The possibility of genetic overlap between risk for SCZ and cognitive phenotypes has been suggested by the presence of cognitive deficits in first-degree relatives of patients with SCZ; however, until recently, molecular genetic approaches to test this overlap have been lacking. Within the last few years, large-scale genome-wide association studies (GWAS) of SCZ have demonstrated that a substantial proportion of the heritability of the disorder is explained by a polygenic component consisting of many common single-nucleotide polymorphisms (SNPs) of extremely small effect. Similar results have been reported in GWAS of general cognitive ability. The primary aim of the present study is to provide the first molecular genetic test of the classic endophenotype hypothesis, which states that alleles associated with reduced cognitive ability should also serve to increase risk for SCZ. We tested the endophenotype hypothesis by applying polygenic SNP scores derived from a large-scale cognitive GWAS meta-analysis (~5000 individuals from nine nonclinical cohorts comprising the Cognitive Genomics consorTium (COGENT)) to four SCZ case-control cohorts. As predicted, cases had significantly lower cognitive polygenic scores compared to controls. In parallel, polygenic risk scores for SCZ were associated with lower general cognitive ability. In addition, using our large cognitive meta-analytic data set, we identified nominally significant cognitive associations for several SNPs that have previously been robustly associated with SCZ susceptibility. Results provide molecular confirmation of the genetic overlap between SCZ and general cognitive ability, and may provide additional insight into pathophysiology of the disorder.


Assuntos
Cognição , Esquizofrenia/genética , Adolescente , Adulto , Idoso , Alelos , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Técnicas de Genotipagem , Humanos , Masculino , Pessoa de Meia-Idade , Herança Multifatorial , Testes Neuropsicológicos , Polimorfismo de Nucleotídeo Único , Risco , Esquizofrenia/epidemiologia , Adulto Jovem
16.
Dis Esophagus ; 28(1): 97-103, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24261350

RESUMO

Apolipoprotein E (ApoE) is the most well-described genetic risk factor for Alzheimer's disease and nonpathological cognitive decline. While possession of the E2 allele may have protective properties, substantial research evidence suggests the E4 allele increases the risk of cognitive degeneration. As neurodegenerative processes are implicated in swallowing dysfunction, we hypothesized that the presence of ApoE 4 would be predictive of dysphagia symptoms in older adults. Eight hundred members of a genetically well characterized community dwelling elderly cohort received the Sydney oropharyngeal dysphagia questionnaire via mail. Cognitive function was also measured using the modified Telephone Interview of Cognitive Status (TiCS-m) and depression with the Geriatric Depression Score (GDS). ApoE allele was genotyped on blood samples from all subjects and data analyzed using standard statistical software (SPSS version 16). Completed questionnaire response rate was 79% (23.5% men, 76.5% women; mean age 81 ± 5 years; range 69-98 years). Possession of one or more of the ApoE 4 and 2 alleles was found in 23.5% and 16%, respectively. Swallowing score was significantly related to GDS (rho 0.133, P < 0.001**) and age (rho 0.107, P < 0.007**) but not general cognitive function as measured by TICS-m. Self-reported swallowing function was not significantly associated with heterozygosity of any allele or homozygosity for E2 or E3 alleles. Although infrequent (1.1% of all subjects) ApoE E4 homozygosity was significantly associated with higher swallowing scores compared to all other allele combinations (P = 0.033) and while attenuated, was still predicted in multivariate regression modeling (B = 0.812; SE = 0.323; P = 0.012). We report the association between ApoE 4 homozygous genotype and self-reported oropharyngeal dysphagia symptoms in community-dwelling older adults. As this association is weakened by the multivariate analysis and the population frequency of ApoE 4 allele homozygosity is low, this finding while intriguing requires replication in larger independent cohorts.


Assuntos
Apolipoproteína E4/genética , Transtornos de Deglutição/genética , Polimorfismo Genético , Idoso , Idoso de 80 Anos ou mais , Alelos , Apolipoproteína E4/sangue , Cognição , Transtornos de Deglutição/sangue , Depressão/genética , Feminino , Frequência do Gene , Homozigoto , Humanos , Masculino , Fatores de Risco , Autorrelato
17.
Diabet Med ; 31(6): 714-20, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24344862

RESUMO

AIMS: To investigate whether there is overlap in the genetic determinants of Type 2 diabetes and cognitive ageing by testing whether a genetic risk score for Type 2 diabetes can predict variation in cognitive function in older people without dementia. METHODS: Type 2 diabetes genetic risk scores were estimated using various single nucleotide polymorphism significance inclusion criteria from an initial genome-wide association study, the largest in Type 2 diabetes to date. Scores were available for 2775-3057 individuals, depending on the cognitive trait. RESULTS: Type 2 diabetes genetic risk was associated with self-reported diabetes mellitus. Across varying single nucleotide polymorphism-inclusion levels, a significant association between Type 2 diabetes genetic risk and change in general cognitive function was found (median r = 0.04); however, this was such that higher Type 2 diabetes genetic risk related to higher cognitive scores. CONCLUSIONS: To investigate more fully the source of the often observed comorbidity between Type 2 diabetes and cognitive impairment, one direction for future research will be to use cognitive ability polygenic risk scores to predict Type 2 diabetes in line with the reverse causation hypothesis that people with lower pre-morbid cognitive ability are more likely to develop Type 2 diabetes.


Assuntos
Transtornos Cognitivos/genética , Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Idoso , Estudos de Coortes , Diabetes Mellitus Tipo 2/psicologia , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
18.
NPJ Vaccines ; 9(1): 11, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38195562

RESUMO

Immunofocusing is a strategy to create immunogens that redirect humoral immune responses towards a targeted epitope and away from non-desirable epitopes. Immunofocusing methods often aim to develop "universal" vaccines that provide broad protection against highly variant viruses such as influenza virus, human immunodeficiency virus (HIV-1), and most recently, severe acute respiratory syndrome coronavirus (SARS-CoV-2). We use existing examples to illustrate five main immunofocusing strategies-cross-strain boosting, mosaic display, protein dissection, epitope scaffolding, and epitope masking. We also discuss obstacles for immunofocusing like immune imprinting. A thorough understanding, advancement, and application of the methods we outline here will enable the design of high-resolution vaccines that protect against future viral outbreaks.

19.
bioRxiv ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38895327

RESUMO

The receptor-binding domain (RBD) of the SARS-CoV-2 spike protein is the main target of neutralizing antibodies. Although they are infrequently elicited during infection or vaccination, antibodies that bind to the conformation-specific cryptic face of the RBD display remarkable breadth of binding and neutralization across Sarbecoviruses. Here, we employed the immunofocusing technique PMD (protect, modify, deprotect) to create RBD immunogens (PMD-RBD) specifically designed to focus the antibody response towards the cryptic-face epitope recognized by the broadly neutralizing antibody S2X259. Immunization with PMD-RBD antigens induced robust binding titers and broad neutralizing activity against homologous and heterologous Sarbecovirus strains. A serum-depletion assay provided direct evidence that PMD successfully skewed the polyclonal antibody response towards the cryptic face of the RBD. Our work demonstrates the ability of PMD to overcome immunodominance and refocus humoral immunity, with implications for the development of broader and more resilient vaccines against current and emerging viruses with pandemic potential.

20.
Nat Biotechnol ; 42(2): 275-283, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37095349

RESUMO

Natural evolution must explore a vast landscape of possible sequences for desirable yet rare mutations, suggesting that learning from natural evolutionary strategies could guide artificial evolution. Here we report that general protein language models can efficiently evolve human antibodies by suggesting mutations that are evolutionarily plausible, despite providing the model with no information about the target antigen, binding specificity or protein structure. We performed language-model-guided affinity maturation of seven antibodies, screening 20 or fewer variants of each antibody across only two rounds of laboratory evolution, and improved the binding affinities of four clinically relevant, highly mature antibodies up to sevenfold and three unmatured antibodies up to 160-fold, with many designs also demonstrating favorable thermostability and viral neutralization activity against Ebola and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pseudoviruses. The same models that improve antibody binding also guide efficient evolution across diverse protein families and selection pressures, including antibiotic resistance and enzyme activity, suggesting that these results generalize to many settings.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Humanos , Testes de Neutralização , Anticorpos Antivirais/genética , Anticorpos Neutralizantes/química , SARS-CoV-2/genética , Mutação
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