A diverse T cell receptor (TCR) repertoire is essential for adaptive immune responses and is generated by somatic recombination of TCRα and TCRβ gene segments in the thymus. Previous estimates of the total TCR diversity have studied the circulating mature repertoire, identifying 1 to 3×10(6) unique TCRβ and 0.5×10(6) TCRα sequences. Here we provide the first estimate of the total TCR diversity generated in the human thymus, an organ which in principle can be sampled in its entirety. High-throughput sequencing of samples from four pediatric donors detected up to 10.3×10(6) unique TCRβ sequences and 3.7×10(6) TCRα sequences, the highest directly observed diversity so far for either chain. To obtain an estimate of the total diversity we then used three different estimators, preseq and DivE, which measure the saturation of rarefaction curves, and Chao2, which measures the size of the overlap between samples. Our results provide an estimate of a thymic repertoire consisting of 40 to 70×10(6) unique TCRβ sequences and 60 to 100×10(6) TCRα sequences. The thymic repertoire is thus extremely diverse. Moreover, extrapolation of the data and comparison with earlier estimates of peripheral diversity also suggest that the thymic repertoire is transient, with different clones produced at different times.
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Sleep
January 2025
UR2NF-Neuropsychology and Functional Neuroimaging Research Unit affiliated at CRCN - Centre for Research in Cognition and Neurosciences and UNI - ULB Neuroscience Institute, Université Libre de Bruxelles (ULB), Brussels, Belgium.
Enhancing the retention of recent memory traces through sleep reactivation is possible via Targeted Memory Reactivation (TMR), involving cueing learned material during post-training sleep. Evidence indicates detectable short-term microstructural changes in the brain within an hour after motor sequence learning, and post-training sleep is believed to contribute to the consolidation of these motor memories, potentially leading to enduring microstructural changes. In this study, we explored how TMR during post-training sleep affects performance gains and delayed microstructural remodeling, using both standard Diffusion Tensor Imaging (DTI) and advanced Neurite Orientation Dispersion & Density Imaging (NODDI).
View Article and Find Full Text PDFExpert Opin Biol Ther
January 2025
OU Stephenson Cancer Center, Oklahoma City.
Introduction: Antibody-drug conjugates (ADCs) are a rapidly evolving class of anti-cancer drugs with a significant impact on management of hematological malignancies including diffuse large B-cell lymphoma (DLBCL). ADCs combine a cytotoxic drug (a.k.
View Article and Find Full Text PDFNeuroinformatics
January 2025
Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, 760 Westwood Plaza, Los Angeles, CA, 90024, USA.
A reader of the peer-reviewed neuroscience literature will often encounter expressions like the following: 'the brain is a dynamic system', 'the brain is a complex network', or 'the brain is a highly metabolic organ'. These expressions attempt to define the essential functions and properties of the mammalian or human brain in a simple phrase or sentence, sometimes using metaphors or analogies. We sought to survey the most common phrases of the form 'the brain is…' in the biomedical literature to provide insights into current conceptualizations of the brain.
View Article and Find Full Text PDFBiochem Genet
January 2025
Wildlife Institute of India, Chandrabani, Dehradun, Uttarakhand, 248001, India.
Indian Himalayan Region (IHR) supports a plethora of biodiversity with a unique assemblage of many charismatic and endemic species. We assessed the genetic diversity, demographic history, and habitat suitability of blue sheep (Pseudois nayaur) in the IHR through the analysis of the mitochondrial DNA (mtDNA) control region (CR) and Cytochrome b gene, and 14 ecological predictor variables. We observed high genetic divergence and designated them into two genetic lineage groups, i.
View Article and Find Full Text PDFCurr Obes Rep
January 2025
Metabolism and Body Composition, Pennington Biomedical Research Center, Baton Rouge, LA, 70808, USA.
Background: Recent technological advances have introduced novel methods for measuring body composition, each with unique benefits and limitations. The choice of method often depends on the trade-offs between accuracy, cost, participant burden, and the ability to measure specific body composition compartments.
Objective: To review the considerations of cost, accuracy, portability, and participant burden in reference and emerging body composition assessment methods, and to evaluate their clinical applicability.
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