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1.
J Immunother ; 47(5): 190-194, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38318726

RESUMO

Single nucleotide polymorphisms (SNPs) in the cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) gene, an inhibitor of T-cell priming, are associated with auto and alloimmunity. Studies implied a role for these SNPs as surrogate markers for immunotherapy-outcome in patients with melanoma. However, no predictive SNPs are defined to date. We analyzed different CTLA-4 SNPs in a large multicenter cohort of patients with ipilimumab-treated melanoma and investigated possible correlations with treatment-related outcomes. Archival blood and/or tumor tissue samples were collected from 361 patients with advanced-stage ipilimumab-treated (±nivolumab) in 6 Swiss and Dutch hospitals. Matrix-assisted laser desorption/ionization-time of flight mass spectrometry based DNA genotyping was performed for 10 different CTLA-4 SNPs: 49A>G, CT60G>A, Jo27T>C, Jo30G>A, Jo31G>T, -658C>T, -1722T>C, -1661A>G, 318C>T, and C>T rs1863800. Associations between different allele genotypes and occurrence of grade ≥3 adverse events (AEs) and survival were tested using univariable logistic regressions or Cox proportional hazard models. 262/361 (73%) patients could be analyzed; 65% of those were males, the median age was 58 years, 39% showed a partial or complete response, and 65% had ≥1 AEs. A TT-genotype of -1722T>C SNP was significantly associated with a lower incidence of grade ≥3 AEs ( P = 0.049), whereas the GG-genotype of CT60G>A correlated with a higher incidence of grade ≥3 AEs ( P = 0.026). The TT-genotype of Jo27T>C SNP ( P = 0.056) and GG-genotype of Jo31G>T ( P = 0.046) were associated with overall survival. CTLA-4 SNPs might predict treatment-related outcomes in patients with melanoma receiving ipilimumab. Confirmatory studies are needed to fully exploit those findings as predictive biomarkers for ipilimumab AEs.


Assuntos
Antígeno CTLA-4 , Ipilimumab , Melanoma , Estadiamento de Neoplasias , Polimorfismo de Nucleotídeo Único , Humanos , Ipilimumab/efeitos adversos , Ipilimumab/uso terapêutico , Antígeno CTLA-4/genética , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/mortalidade , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Genótipo , Adulto , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Resultado do Tratamento
2.
Biomedicines ; 12(1)2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38275395

RESUMO

Due to substantial improvements in read accuracy, third-generation long-read sequencing holds great potential in blood group diagnostics, particularly in cases where traditional genotyping or sequencing techniques, primarily targeting exons, fail to explain serological phenotypes. In this study, we employed Oxford Nanopore sequencing to resolve all genotype-phenotype discrepancies in the Kidd blood group system (JK, encoded by SLC14A1) observed over seven years of routine high-throughput donor genotyping using a mass spectrometry-based platform at the Blood Transfusion Service, Zurich. Discrepant results from standard serological typing and donor genotyping were confirmed using commercial PCR-SSP kits. To resolve discrepancies, we amplified the entire coding region of SLC14A1 (~24 kb, exons 3 to 10) in two overlapping long-range PCRs in all samples. Amplicons were barcoded and sequenced on a MinION flow cell. Sanger sequencing and bridge-PCRs were used to confirm findings. Among 11,972 donors with both serological and genotype data available for the Kidd system, we identified 10 cases with unexplained conflicting results. Five were linked to known weak and null alleles caused by variants not included in the routine donor genotyping. In two cases, we identified novel null alleles on the JK*01 (Gly40Asp; c.119G>A) and JK*02 (Gly242Glu; c.725G>A) haplotypes, respectively. Remarkably, the remaining three cases were associated with a yet unknown deletion of ~5 kb spanning exons 9-10 of the JK*01 allele, which other molecular methods had failed to detect. Overall, nanopore sequencing demonstrated reliable and accurate performance for detecting both single-nucleotide and structural variants. It possesses the potential to become a robust tool in the molecular diagnostic portfolio, particularly for addressing challenging structural variants such as hybrid genes, deletions and duplications.

3.
Vox Sang ; 119(4): 377-382, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38226545

RESUMO

BACKGROUND AND OBJECTIVES: Mixed-field agglutination in ABO phenotyping (A3, B3) has been linked to genetically different blood cell populations such as in chimerism, or to rare variants in either ABO exon 7 or regulatory regions. Clarification of such cases is challenging and would greatly benefit from sequencing technologies that allow resolving full-gene haplotypes at high resolution. MATERIALS AND METHODS: We used long-read sequencing by Oxford Nanopore Technologies to sequence the entire ABO gene, amplified in two overlapping long-range PCR fragments, in a blood donor presented with A3B phenotype. Confirmation analyses were carried out by Sanger sequencing and included samples from other family members. RESULTS: Our data revealed a novel heterozygous g.10924C>A variant on the ABO*A allele located in the transcription factor binding site for RUNX1 in intron 1 (+5.8 kb site). Inheritance was shown by the results of the donor's mother, who shared the novel variant and the anti-A specific mixed-field agglutination. CONCLUSION: We discovered a regulatory variant in the 8-bp RUNX1 motif of ABO, which extends current knowledge of three other variants affecting the same motif and also leading to A3 or B3 phenotypes. Overall, long-range PCR combined with nanopore sequencing proved powerful and showed great potential as an emerging strategy for resolving cases with cryptic ABO phenotypes.


Assuntos
Sistema ABO de Grupos Sanguíneos , Subunidade alfa 2 de Fator de Ligação ao Core , Humanos , Íntrons/genética , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Fenótipo , Alelos , Sítios de Ligação , Sistema ABO de Grupos Sanguíneos/genética , Genótipo
4.
Blood Adv ; 7(6): 878-892, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36129841

RESUMO

In the era of blood group genomics, reference collections of complete and fully resolved blood group gene alleles have gained high importance. For most blood groups, however, such collections are currently lacking, as resolving full-length gene sequences as haplotypes (ie, separated maternal/paternal origin) remains exceedingly difficult with both Sanger and short-read next-generation sequencing. Using the latest third-generation long-read sequencing, we generated a collection of fully resolved sequences for all 6 main ABO allele groups: ABO∗A1/A2/B/O.01.01/O.01.02/O.02. We selected 77 samples from an ABO genotype data set (n = 25 200) of serologically typed Swiss blood donors. The entire ABO gene was amplified in 2 overlapping long-range polymerase chain reactions (covering ∼23.6 kb) and sequenced by long-read Oxford Nanopore sequencing. For quality validation, 2 samples per ABO group were resequenced using Illumina and Pacific Biosciences technology. All 154 full-length ABO sequences were resolved as haplotypes. We observed novel, distinct sequence patterns for each ABO group. Most genetic diversity was found between, not within, ABO groups. Phylogenetic tree and haplotype network analyses highlighted distinct clades of each ABO group. Strikingly, our data uncovered 4 genetic variants putatively specific for ABO∗A1, for which direct diagnostic targets are currently lacking. We validated A1-diagnostic potential using whole-genome data (n = 4872) of a multiethnic cohort. Overall, our sequencing strategy proved powerful for producing high-quality ABO haplotypes and holds promise for generating similar collections for other blood groups. The publicly available collection of 154 haplotypes will serve as a valuable resource for molecular analyses of ABO, as well as studies about the function and evolutionary history of ABO.


Assuntos
Sistema ABO de Grupos Sanguíneos , Humanos , Alelos , Haplótipos , Sistema ABO de Grupos Sanguíneos/genética , Filogenia , Genótipo
5.
Eur Arch Psychiatry Clin Neurosci ; 272(1): 107-118, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33725165

RESUMO

Internet-delivered interventions can be effective in treating mental disorders. However, their rate of use in German psychiatric inpatient routine care is low. The current study aimed to investigate the attitude of mental health care professionals working in inpatient care regarding internet-delivered interventions, including presumed benefits, barriers and facilitators. In total, 176 health professionals from ten inpatient psychiatric hospitals throughout Germany were surveyed on site. The professionals' attitude towards internet-delivered interventions in inpatient care was assessed by an adapted version of the 'Attitude toward Telemedicine in Psychiatry and Psychotherapy' (ATTiP) questionnaire. To identify benefits, barriers and facilitators, we developed open-response questions that were based on the 'Unified Theory of Acceptance and Use of Technology' (UTAUT) and analyzed by a qualitative content analysis. Professionals reported little experience or knowledge about internet-delivered interventions. Their attitude towards internet-delivered interventions in psychiatric inpatient care was rather indifferent. The most frequently mentioned potential benefits were an optimised treatment structure and patient empowerment; the most frequently anticipated barriers were too severe symptoms of patients, the feared neglect of face-to-face contacts and insufficient technical equipment; and the most frequently mentioned facilitators were high usability of the internet-based intervention, a sufficient functional level of the patient and further education of staff. For successful implementation in the inpatient sector, internet-delivered interventions must be adapted to the special needs of severely mentally ill patients and to the hospital management systems and workflow. In addition, technical preconditions (internet access, devices) must be met. Last, further education of mental health care professionals is needed.


Assuntos
Atitude do Pessoal de Saúde , Intervenção Baseada em Internet , Transtornos Mentais , Alemanha , Hospitalização , Humanos , Transtornos Mentais/terapia , Serviços de Saúde Mental
6.
Transfus Med Hemother ; 47(4): 326-336, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32884505

RESUMO

The U antigen (MNS5) is one of 49 antigens belonging to the MNS blood group system (ISBT002) carried on glycophorins A (GPA) and B (GPB). U is present on the red blood cells in almost all Europeans and Asians but absent in approximately 1.0% of Black Africans. U negativity coincides with negativity for S (MNS3) and s (MNS4) on GPB, thus be called S-s-U-, and is thought to arise from homozygous deletion of GYPB. Little is known about the molecular background of these deletions. Bioinformatic analysis of the 1000 Genomes Project data revealed several candidate regions with apparent deletions in GYPB. Highly specific Gap-PCRs, only resulting in positive amplification from DNAs with deletions present, allowed for the exact genetic localization of 3 different breakpoints; 110.24- and 103.26-kb deletions were proven to be the most frequent in Black Americans and Africans. Among 157 CEPH DNAs, deletions in 6 out of 8 African ethnicities were present. Allele frequencies of the deletions within African ethnicities varied greatly and reached a cumulative 23.3% among the Mbuti Pygmy people from the Congo. Similar observations were made for U+var alleles, known to cause strongly reduced GPB expression. The 110- and 103-kb deletional GYPB haplotypes were found to represent the most prevalent hereditary factors causative of the MNS blood group phenotype S-s-U-. Respective GYPB deletions are now accessible by molecular detection of homo- and hemizygous transmission.

7.
Transfus Med Hemother ; 45(4): 239-250, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30283273

RESUMO

BACKGROUND: High-frequency blood group antigens (HFA) are present in >90% of the human population, according to some reports even in >99% of individuals. Therefore, patients lacking HFA may become challenging for transfusion support because compatible blood is hardly found, and if the patient carries alloantibodies, the cross-match will be positive with virtual every red cell unit tested. METHODS: In this study, we applied high-throughput blood group SNP genotyping on >37,000 Swiss blood donors, intending to identify homozygous carriers of low-frequency blood group antigens (LFA). RESULTS: 326 such individuals were identified and made available to transfusion specialists for future support of patients in need of rare blood products. CONCLUSION: Thorough comparison of minor allele frequencies using population genetics revealed heterogeneity of allele distributions among Swiss blood donors which may be explained by the topographical and cultural peculiarities of Switzerland. Moreover, geographically localized donor subpopulations are described which contain above-average numbers of individuals carrying rare blood group genotypes.

8.
Appetite ; 116: 147-156, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28461198

RESUMO

Excess consumption of added dietary sugars is related to multiple metabolic problems and adverse health conditions. Identifying the modifiable social cognitive and motivational constructs that predict sugar consumption is important to inform behavioral interventions aimed at reducing sugar intake. We tested the efficacy of an integrated dual-process, dual-phase model derived from multiple theories to predict sugar consumption. Using a prospective design, university students (N = 90) completed initial measures of the reflective (autonomous and controlled motivation, intentions, attitudes, subjective norm, perceived behavioral control), impulsive (implicit attitudes), volitional (action and coping planning), and behavioral (past sugar consumption) components of the proposed model. Self-reported sugar consumption was measured two weeks later. A structural equation model revealed that intentions, implicit attitudes, and, indirectly, autonomous motivation to reduce sugar consumption had small, significant effects on sugar consumption. Attitudes, subjective norm, and, indirectly, autonomous motivation to reduce sugar consumption predicted intentions. There were no effects of the planning constructs. Model effects were independent of the effects of past sugar consumption. The model identified the relative contribution of reflective and impulsive components in predicting sugar consumption. Given the prominent role of the impulsive component, interventions that assist individuals in managing cues-to-action and behavioral monitoring are likely to be effective in regulating sugar consumption.


Assuntos
Regulação do Apetite , Dieta Saudável , Açúcares da Dieta/administração & dosagem , Preferências Alimentares , Modelos Biológicos , Modelos Psicológicos , Cooperação do Paciente , Adaptação Psicológica , Adulto , Austrália , Dieta Saudável/psicologia , Açúcares da Dieta/efeitos adversos , Feminino , Preferências Alimentares/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Comportamento Impulsivo , Intenção , Masculino , Cooperação do Paciente/psicologia , Pacientes Desistentes do Tratamento , Autorrelato , Autocontrole/psicologia , Estudantes , Universidades , Adulto Jovem
9.
Br J Haematol ; 174(4): 624-36, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27072601

RESUMO

Results of genotyping with true high-throughput capability for MNSs antigens are underrepresented, probably because of technical issues, due to the high level of nucleotide sequence homology of the paralogous genes GYPA, GYPB and GYPE. Eight MNSs-specific single nucleotide polymorphisms (SNP) were detected using matrix-assisted laser desorption/ionization, time-of-flight mass spectrometry (MALDI-TOF MS) in 5800 serologically M/N and S/s pre-typed Swiss blood donors and 50 individuals of known or presumptive black African ethnicity. Comparison of serotype with genotype delivered concordance rates of 99·70% and 99·90% and accuracy of genotyping alone of 99·88% and 99·95%, for M/N and S/s, respectively. The area under the curve of peak signals was measured in intron 1 of the two highly homologous genes GYPB and GYPE and allowed for gene copy number variation estimates in all individuals investigated. Elevated GYPB:GYPE ratios accumulated in several carriers of two newly observed GYP*401 variants, termed type G and H, both encoding for the low incidence antigen St(a). In black Africans, reduced GYPB gene contents were proven in pre-typed S-s-U- phenotypes and could be reproduced in unknown specimens. Quantitative gene copy number estimates represented a highly attractive supplement to conventional genotyping, solely based on MNSs SNPs.


Assuntos
Antígenos de Grupos Sanguíneos/genética , Dosagem de Genes , Genótipo , Sistema do Grupo Sanguíneo MNSs/genética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Alelos , População Negra , Etnicidade , Glicoforinas/genética , Humanos , Polimorfismo de Nucleotídeo Único
10.
Methods Mol Biol ; 1310: 51-70, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26024625

RESUMO

Most blood group antigens are defined by single nucleotide polymorphisms (SNPs). Highly accurate MALDI-TOF MS has proven its potential in SNP genotyping and was therefore chosen for blood donor oriented genotyping with high-throughput capability, e.g., 380 samples per day. The Select Module covers a total of 36 SNPs in two single-tube reactions, representative of 46 blood group and 4 human platelet antigens. Using this tool, confirmatory blood group typing for RhD, RhCE, Kell, Kidd, Duffy, MN, Ss, and selected rare antigens is performed on a routine basis.


Assuntos
Antígenos de Plaquetas Humanas/genética , Antígenos de Grupos Sanguíneos/genética , Técnicas de Genotipagem/métodos , Polimorfismo de Nucleotídeo Único , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Antígenos de Plaquetas Humanas/análise , Sequência de Bases , Antígenos de Grupos Sanguíneos/análise , DNA/análise , DNA/genética , Genótipo , Técnicas de Genotipagem/economia , Sequenciamento de Nucleotídeos em Larga Escala/economia , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Dados de Sequência Molecular , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/economia
11.
Transfusion ; 54(12): 3198-207, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24845979

RESUMO

BACKGROUND: After the ABO (ABO) and Rh (RHD and RHCE) blood group systems, Kell (KEL), Kidd (SLC14A1), and Duffy (DARC) represent the second most important clinically relevant antigens. STUDY DESIGN AND METHODS: Samples from 4000 Swiss blood donors, with serologic prevalues for K/k, Kp(a/b), Jk(a/b), and Fy(a/b), and 48 additional samples of presumptive black African origin were genotyped using high-throughput matrix-assisted laser desorption/ionization, time-of-flight mass spectrometry, applying one single-multiplex polymerase chain reaction/primer-extension reaction simultaneously detecting 15 single-nucleotide polymorphisms. RESULTS: Genotype/phenotype concordance for K/k, Kp(a/b), Jk(a/b), and all Fy(a/b) specificities were 100, 99.98, 99.93, and 99.20%, respectively. Discrepancies were caused by erroneous serologic profiles (n = 33), mainly attributed to weakly expressed Fy(x) (n = 28). Only three discrepancies had a genetic basis. They could all be explained by newly observed silenced alleles: one KEL*02N.34 and one FY*02N.03 with predicted R700Q and G261R amino acid exchanges, respectively, and one JK*B, with an as-yet-unidentified silencing cause. According to NCBI SNP database entry for rs8176034, another new allele, KEL*02.38, had been expected, and we formally demonstrated its presence. We furthermore identified individuals with rare phenotypes, such as Js(a/b) heterozygotes among Caucasians, rare alleles, the "Swiss" JK*01N.03, and rare genotypes, such as one Fy(x) homozygote. CONCLUSION: Genotyping proved its practicability in the daily routine setting and qualitatively outperformed serology. Technology is ideal for time-insensitive donor genotyping and allows for a broad range of throughput needs. Consequently, from a technologic point of view, serotyping should be replaced by genotyping for donors' blood groups encoded by KEL, SLC14A1, and DARC.


Assuntos
Alelos , Sistema do Grupo Sanguíneo Duffy/genética , Técnicas de Genotipagem/métodos , Sistema do Grupo Sanguíneo Kidd/genética , Glicoproteínas de Membrana/genética , Metaloendopeptidases/genética , Receptores de Superfície Celular/genética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Adulto , Bases de Dados de Ácidos Nucleicos , Sistema do Grupo Sanguíneo Duffy/química , Feminino , Técnicas de Genotipagem/instrumentação , Humanos , Sistema do Grupo Sanguíneo Kidd/química , Masculino , Glicoproteínas de Membrana/química , Metaloendopeptidases/química , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Receptores de Superfície Celular/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/instrumentação , Suíça
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