20 research outputs found

    Clinical T Cell Receptor Repertoire Deep Sequencing and Analysis: An Application to Monitor Immune Reconstitution Following Cord Blood Transplantation

    Get PDF
    Spectratyping assays are well recognized as the clinical gold standard for assessing the T cell receptor (TCR) repertoire in haematopoietic stem cell transplant (HSCT) recipients. These assays use length distributions of the hyper variable complementarity-determining region 3 (CDR3) to characterize a patient's T cell immune reconstitution post-transplant. However, whilst useful, TCR spectratyping is notably limited by its resolution, with the technique unable to provide data on the individual clonotypes present in a sample. High-resolution clonotype data are necessary to provide quantitative clinical TCR assessments and to better understand clonotype dynamics during clinically relevant events such as viral infections or GvHD. In this study we developed and applied a CDR3 Next Generation Sequencing (NGS) methodology to assess the TCR repertoire in cord blood transplant (CBT) recipients. Using this, we obtained comprehensive TCR data from 16 CBT patients and 5 control cord samples at Great Ormond Street Hospital (GOSH). These were analyzed to provide a quantitative measurement of the TCR repertoire and its constituents in patients post-CBT. We were able to both recreate and quantify inferences typically drawn from spectratyping data. Additionally, we demonstrate that an NGS approach to TCR assessment can provide novel insights into the recovery of the immune system in these patients. We show that NGS can be used to accurately quantify TCR repertoire diversity and to provide valuable inference on clonotypes detected in a sample. We serially assessed the progress of T cell immune reconstitution demonstrating that there is dramatic variation in TCR diversity immediately following transplantation and that the dynamics of T cell immune reconstitution is perturbed by the presence of GvHD. These findings provide a proof of concept for the adoption of NGS TCR sequencing in clinical practice

    Time course survival of <i>Busseola fusca</i> larvae.

    No full text
    <p>Larval survival on <i>Bt</i> and non-<i>Bt</i> (<i>NBt</i>) corn as a function of time, for the crosses S × S, R × R and R × S. Points correspond to the average observed survival. Shaded areas correspond to the respective minimum and maximum observed survival.</p

    Data from: Genetic hitchhiking and resistance evolution to transgenic Bt toxins: insights from the African stalk borer Busseola fusca (Noctuidae)

    No full text
    Since transgenic crops expressing Bacillus thuringiensis (Bt) toxins were first released, resistance evolution leading to failure in control of pests populations has been observed in a number of species. Field resistance of the moth Busseola fusca was acknowledged 8 years after Bt maize was introduced in South Africa. Since then, field resistance of this corn borer has been observed at several locations, raising questions about the nature, distribution and dynamics of the resistance trait. Using genetic markers, our study identified four outlier loci clearly associated with resistance. In addition, genetic structure at neutral loci reflected extensive gene flow among populations. A realistically parameterised model suggests that resistance could travel in space at speed of several kilometres a year. Markers at outlier loci delineated a geographic region associated with resistance spread. This was an area of approximately 100 km radius, including the location where resistance was first reported. Controlled crosses corroborated these findings and showed significant differences of progeny survival on Bt plants depending on the origin of the resistant parent. Last, our study suggests diverse resistance mutations, which would explain the widespread occurrence of resistant larvae in Bt fields across the main area of maize production in South Africa

    Deficient anterior pituitary with common variable immune deficiency (DAVID syndrome): a new case and literature reports

    No full text
    Deficient anterior pituitary with common variable immune deficiency (DAVID) syndrome is a rare condition characterized by adrenocorticotropic hormone (ACTH) deficiency and primary hypogammaglobulinemia. It is due to heterozygous mutations of the nuclear factor kappa-B subunit 2 (NFKB2) gene. Only a few isolated cases have been reported since its first description by our team. Through the international multicenter GENHYPOPIT network, we identified a new case of DAVID syndrome. We then conducted an extensive review of the DAVID syndrome cases published from 2012 to 2022. A 7-year-old boy was diagnosed with symptomatic hypoglycemia revealing ACTH deficiency. Laboratory tests showed asymptomatic hypogammaglobulinemia. He harbored a heterozygous point mutation in NFKB2 gene (c.2600C > T, p.Ala867Val). His management included hydrocortisone replacement treatment, and he also received subcutaneous immunoglobulins during the Covid-19 pandemic. We analyzed 28 cases of DAVID syndrome with ACTH deficiency. ACTH deficiency was the only hormone deficiency in 79% of patients, but some patients harbored growth hormone (GH) and thyroid stimulating hormone (TSH) deficiencies. The first presenting symptoms were sinus/pulmonary infections (82%, mean age of 3 years) and alopecia (mean age of 4.7 years). ACTH deficiency was the third presenting condition (mean age at diagnosis of 8.6 years). All patients had hypogammaglobulinemia (decreased IgA and IgM levels), and 57% of patients had at least one autoimmune manifestation. Heterozygous mutations at the 3′end of the NFKB2 gene, coding for the C-terminal domain of the protein, were identified in all cases. Better knowledge of DAVID syndrome will help clinicians make an early diagnosis to avoid life-threatening complications

    non-outlier-loci

    No full text
    The columns of the table correspond to the non-outlier loci presented in Campagne et al. 2016 (Heredity). Rows, correspond to individuals (described in the file sample-info.txt)

    Acute megakaryoblastic leukemia (excluding Down syndrome) remains an acute myeloid subgroup with inferior outcome in the French ELAM02 trial

    No full text
    International audienceWe report the outcome of 27 children with de novo acute megakaryoblastic leukemia (AMKL) (excluding Down syndrome) enrolled in the French multicenter prospective study ELAM02 (2005-2011). There was no difference in gender, initial leukocyte count, CNS involvement, and complete remission rate (88.9%), as compared to other acute myeloid leukemia (AML) subtypes. AMKL patients had a significantly poorer outcome (5-year overall survival 54% [CI 95% 33%-71%] than children with other AML subtypes (5-year overall survival 73% [CI 95% 68%-77%] p = 0.02). Gender, age, CNS leukemia, hyperleukocytosis, complete remission or cytogenetic subgroups were not significant prognostic factors of disease-free survival. AMKL (excluding Down syndrom) remains an AML subgroup with inferior outcome

    sample information

    No full text
    'Field.ID' corresponds to the field numbers/IDs in which a larvae was sampled; 'Type.of.field', describes whether the field sampled was Bt maize (i.e., Bt) or a non-Bt crop (maize or sorghum, i.e., nBt)
    corecore