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Biology subjects

De Vlaminck, I.

Publications and source records attributed to De Vlaminck, I..

4 recordsLinked to original sources

Simultaneous multiplexed amplicon sequencing and transcriptome profiling in single cells

We describe Droplet Assisted RNA Targeting by single cell sequencing (DART-seq), a versatile technology that enables multiplexed amplicon sequencing and transcriptome profiling in single cells. We applied DART-seq to simultaneously characterize the non-A-tailed transcripts of a segmented dsRNA virus and the transcriptome of the infected cell. In addition, we used DART-seq to simultaneously determine the natively paired, variable region heavy and light chain amplicons and the transcriptome of B lymphocytes.

genomics

Host-pathogen interactions in urinary tract infection from the structure and diversity of urinary cell-free DNA

Infections of the urinary tract are the most common form of infection in the human population. Here, we tested the utility of urinary cell-free DNA (cfDNA) to comprehensively monitor host and pathogen dynamics in the scope of bacterial and viral urinary tract infections. We assayed cfDNA isolated from 141 urine samples obtained from a cohort of 82 kidney transplant recipients by next-generation sequencing. We find that urinary cfDNA simultaneously informs about the composition of the bacterial and viral components of the microbiome, antimicrobial susceptibility, bacterial growth dynamics, kidney allograft injury, and the host response to infection. These different layers of information are accessible from a single assay and individually agree with corresponding clinical tests based on quantitative PCR, conventional bacterial culture, and urinalysis. In addition, cfDNA reveals the frequent occurrence of pathologies that remain undiagnosed in conventional diagnostic workups. Our work identifies urinary cfDNA as a highly versatile tool to monitor infections of the urinary tract.

genomics

Vast population genetic diversity underlies the treatment dynamics of ETV6-RUNX1 ALL

Ensemble-averaged genome profiling of diagnostic samples suggests that acute leukemias harbor few somatic genetic alterations. We used single-cell exome and error-corrected sequencing to survey the genetic diversity underlying ETV6-RUNX1 acute lymphoblastic leukemia (ALL) at high resolution. The survey uncovered a vast range of low-frequency genetic variants that were undetected in conventional bulk assays, including additional clone-specific \"driver\" RAS mutations. Single-cell exome sequencing revealed APOBEC mutagenesis to be important in disease initiation but not in progression and identified many more mutations per cell than previously found. Using this data, we created a branching model of ETV6-RUNX1 ALL development that recapitulates the genetic features of patients. Exposure of leukemic populations to chemotherapy selected for specific clones in a dose-dependent manner. Together, these data have important implications for understanding the development and treatment response of childhood leukemia, and they provide a framework for using population genetics to deeply interrogate cancer clonal evolution.\n\nOne-Sentence SummaryAPOBEC and replication-associated mutagenesis contribute to the development of ETV6-RUNX1 ALL, creating massive leukemic population genetic diversity that results in clonal differences in susceptibilities to chemotherapy.

cancer biology

Humans are colonized by many uncharacterized and highly divergent microbes

Blood circulates throughout the entire body and contains molecules drawn from virtually every tissue, including the microbes and viruses which colonize the body. Through massive shotgun sequencing of circulating cell-free DNA from the blood, we identified hundreds of new bacteria and viruses which represent previously unidentified members of the human microbiome. Analysing cumulative sequence data from 1,351 blood samples collected from 188 patients enabled us to assemble 7,190 contiguous regions (contigs) larger than 1 kbp, of which 3,761 are novel with little or no sequence homology in any existing databases. The vast majority of these novel contigs possess coding sequences, and we have validated their existence both by finding their presence in independent experiments and by performing direct PCR amplification. When their nearest neighbors are located in the tree of life, many of the organisms represent entirely novel taxa, showing that microbial diversity within the human body is substantially broader than previously appreciated.

microbiology