Biology subjects

Delley, C. L.

Publications and source records attributed to Delley, C. L..

7 recordsLinked to original sources

bioRxiv2025

The Immunophenotype and Proviral Landscape of HIV-infected CD4 T Cells During Antiretroviral Therapy

In individuals on effective antiretroviral therapy, integrated HIV proviruses persist within CD4 T cells, forming a viral reservoir that rebounds if treatment is stopped. Identifying and targeting these rare, infected cells is critical for advancing therapies, but methods to study reservoir cells are limited and their unique properties remain largely unknown. We applied DAb-seq, a high-throughput method that combines single-cell DNA and surface protein sequencing, to profile over five hundred and twenty thousand CD4 T cells from the blood of six individuals on ART. Infected cells were unequally distributed in T cell subsets, and differential protein expression between infected and uninfected cells revealed significant heterogeneity across cell subsets. Attempts to identify surface markers that differentiate infected from uninfected cells found antigens that mirrored the enrichment of HIV in central memory subsets. However, while central memory T cells harbored the majority of HIV, cells with intact provirus were enriched relative to their defective counterparts in Naive and Regulatory T cell subsets, suggesting that they differentially maintain intact proviruses. In summary, we developed DAb-seq as an open-source platform for linking the proviral landscape to diverse cellular phenotypes, revealing heterogeneity in surface protein expression and provirus maintenance across infected subsets.

genomics↗

bioRxiv2025

High-Throughput Antibody Neutralization Screening in Massively Parallel Droplet Arrays

Neutralizing antibodies provide rapid immune defense against infectious diseases, but are difficult to discover at scale because neutralization assays require live reporter cells and soluble monoclonal antibodies. Here we report Droplet Reporter Cell Testing for Neutralization (DrReCT-Neutralization) to screen antibody gene libraries for their ability to neutralize viral infections. We established the necessary engineered cell lines and validated the DrReCT screening platform using synthetic oligoclonal libraries, followed by an example discovery campaign that demonstrated scalable functional antibody data collection against viral diseases.

immunology↗

bioRxiv2023

Multiomic Single Cell Sequencing Identifies Stemlike Nature of Mixed Phenotype Acute Leukemia and Provides Novel Risk Stratification

Mixed phenotype acute leukemia (MPAL) is a leukemia whose biologic drivers are poorly understood, therapeutic strategy remains unclear, and prognosis is poor. We performed multiomic single cell (SC) profiling of 14 newly diagnosed adult MPAL patients to characterize the immunophenotypic, genetic, and transcriptional landscapes of MPAL. We show that neither genetic profile nor transcriptome reliably correlate with specific MPAL immunophenotypes. However, progressive acquisition of mutations is associated with increased expression of immunophenotypic markers of immaturity. Using SC transcriptional profiling, we find that MPAL blasts express a stem cell-like transcriptional profile distinct from other acute leukemias and indicative of high differentiation potential. Further, patients with the highest differentiation potential demonstrated inferior survival in our dataset. A gene set score, MPAL95, derived from genes highly enriched in this cohort, is applicable to bulk RNA sequencing data and was predictive of survival in an independent patient cohort, suggesting utility for clinical risk stratification.

cancer biology↗

bioRxiv2022

Microfluidics-free single-cell genomics with templated emulsification

Single-cell RNA sequencing is now a standard method used to reveal the molecular details of cellular heterogeneity, but current approaches have limitations on speed, scale, and ease of use that stem from the complex microfluidic devices or fluid handling steps required for sample processing. We, therefore, developed a method that does not require specialized microfluidic devices, expertise, or hardware. Our approach is based on particle-templated emulsification, which allows single-cell encapsulation and barcoding of cDNA in uniform droplet emulsions with only a vortexer. PIP-seq accommodates a wide range of emulsification formats, including microwell plates and large-volume conical tubes, enabling thousands of samples or millions of cells to be processed in minutes. We demonstrate that PIP-seq produces high-purity transcriptomes in mouse-human mixing studies, is compatible with multi-omics measurements, and can accurately characterize cell types in human breast tissue when compared to a commercial microfluidic platform. Single-cell transcriptional profiling of mixed phenotype acute leukemia using PIP-seq revealed the emergence of heterogeneity within chemotherapy-resistant cell subsets that were hidden by standard immunophenotyping. PIP-seq is a simple, flexible, and scalable next-generation workflow that extends single-cell sequencing to new applications, including screening, diagnostics, and disease monitoring.

genomics↗

bioRxiv2020

Modular barcode beads for microfluidic single cell genomics

Barcode beads allow efficient nucleic acid tagging in single cell genomics. Current barcode designs, however, are fabricated with a particular application in mind. Repurposing to novel targets, or altering to add additional targets as information is obtained is possible but the result is suboptimal. Here, we describe a modular framework that simplifies generation of multifunctional beads and allows their easy extension to new targets. One Sentence SummaryWe describe an optimized design for barcoding beads which are useful for single cell RNA and DNA sequencing.

cell biology↗

bioRxiv2020

Joint profiling of proteins and DNA in single cells reveals extensive proteogenomic decoupling in leukemia

Studies of acute myeloid leukemia rely on DNA sequencing and immunophenotyping by flow cytometry as primary tools for disease characterization. However, leukemia tumor heterogeneity complicates integration of DNA variants and immunophenotypes from separate measurements. Here we introduce DAb-seq, a novel technology for simultaneous capture of DNA genotype and cell surface phenotype from single cells at high throughput, enabling direct profiling of proteogenomic states in tens of thousands of cells. To demonstrate the approach, we analyze the disease of three patients with leukemia over multiple treatment timepoints and disease recurrences. We observe complex genotype-phenotype dynamics that illustrate the subtlety of the disease process and the degree of incongruity between blast cell genotype and phenotype in different clinical scenarios. Our results highlight the importance of combined single-cell DNA and protein measurements to fully characterize the heterogeneity of leukemia.

cancer biology↗

bioRxiv2017

Combined aptamer and transcriptome sequencing of single cells

The transcriptome and proteome encode distinct information that is important for characterizing heterogeneous biological systems. We demonstrate a method to simultaneously characterize the transcriptomes and proteomes of single cells at high throughput using aptamer probes and droplet-based single cell sequencing. With our method, we differentiate distinct cell types based on aptamer surface binding and gene expression patterns. Aptamers provide advantages over antibodies for single cell protein characterization, including rapid, in vitro, and high-purity generation via SELEX, and the ability to amplify and detect them with PCR and sequencing.

cell biology↗