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Biology subjects

Martin-Alonso, C.

Publications and source records attributed to Martin-Alonso, C..

2 recordsLinked to original sources

Inhalable point-of-care urinary diagnostic platform

The late-stage detection of lung cancer leads to a high global mortality rate. Although low-dose computed tomography screening improves lung cancer survival in at-risk groups, this test still suffers from high rates of false positive results. In addition, inequality remains in the diagnosis of lung cancer as access to medical imaging infrastructure is limited. Here, we designed a needleless and imaging-free platform, termed PATROL (point-of-care aerosolizable nanosensors with tumor-responsive oligonucleotide barcodes), to increase detection accuracy, to reduce resource disparities for early detection of lung cancer, and to enable timely interception. PATROL formulates a set of DNA-barcoded, activity-based nanosensors (ABNs) into inhalable formats that can be delivered using clinical nebulizers or inhalers. Lung cancer-associated proteases in the tumor microenvironment selectively cleave the ABNs, releasing synthetic DNA reporters that are eventually excreted via the urine. The barcoded nanosensor signatures present in urine samples are quantified within 20 minutes using a multiplexable paper-based lateral flow assay at room temperature. PATROL detects early-stage tumors in an autochthonous lung adenocarcinoma mouse model with high sensitivity and specificity. Tailoring the library of ABNs may enable the modular PATROL platform to not only lower the resource thresholds required for early detection of lung cancer, but also enable rapid detection of chronic pulmonary disorders and infections.

bioengineering↗

An intravenous DNA-binding priming agent protects cell-free DNA and improves the sensitivity of liquid biopsies

Blood-based, or "liquid," biopsies enable minimally invasive diagnostics but have limits on sensitivity due to scarce cell-free DNA (cfDNA). Improvements to sensitivity have primarily relied on enhancing sequencing technology ex vivo. Here, we sought to augment the level of circulating tumor DNA (ctDNA) detected in a blood draw by attenuating the clearance of cfDNA in vivo. We report a first-in-class intravenous DNA-binding priming agent given 2 hours prior to a blood draw to recover more cfDNA. The DNA-binding antibody minimizes nuclease digestion and organ uptake of cfDNA, decreasing its clearance at 1 hour by over 150-fold. To improve plasma persistence and limit potential immune interactions, we abrogated its Fc-effector function. We found that it protects GC-rich sequences and DNase-hypersensitive sites, which are ordinarily underrepresented in cfDNA. In tumor-bearing mice, priming improved tumor DNA recovery by 19-fold and sensitivity for detecting cancer from 6% to 84%. These results suggest a novel method to enhance the sensitivity of existing DNA-based cancer testing using blood biopsies.

genomics↗