ABSTRACT
Prompt on-site diagnosis of SARS-CoV-2 with other respiratory infections would have minimized the global impact of the COVID-19 pandemic through rapid, effective management. However, no such multiplex point-of-care (POC) chip has satisfied a suitable sensitivity of gold-standard nucleic acid amplification tests (NAATs). Here, we present a rapid multiplexed ultrasensitive sample-to-answer LAMP (MUSAL) chip operated by simple LED-driven photothermal amplification to detect six targets from single-swab sampling. First, our MUSAL chip allows ultrafast on-chip sample preparation with â¼500-fold preconcentration at a rate of 1.2 mL min-1 . Second, our chip enables contamination-free amplification using autonomous target elution into on-chip reagents by photothermal activation. Finally, our chip accomplishes multiplexed on-chip diagnostics of SARS-CoV-2 and influenza viruses with a limit of detection (LoD) of 0.5 copies µL-1 . Our rapid, ultra-sensitive, cost-effective sample-to-answer chip with a multiplex capability will allow timely management of various pandemics situations we may face shortly. This article is protected by copyright. All rights reserved.
ABSTRACT
SARS-CoV-2 precipitates respiratory distress by infection of airway epithelial cells and is often accompanied by acute kidney injury. We report that Kidney Injury Molecule-1/T cell immunoglobulin mucin domain 1 (KIM-1/TIM-1) is expressed in lung and kidney epithelial cells in COVID-19 patients and is a receptor for SARS-CoV-2. Human and mouse lung and kidney epithelial cells express KIM-1 and endocytose nanoparticles displaying the SARS-CoV-2 spike protein (virosomes). Uptake was inhibited by anti-KIM-1 antibodies and TW-37, a newly discovered inhibitor of KIM-1-mediated endocytosis. Enhanced KIM-1 expression by human kidney tubuloids increased uptake of virosomes. KIM-1 binds to the SARS-CoV-2 Spike protein in vitro . KIM-1 expressing cells, not expressing angiotensin-converting enzyme 2 (ACE2), are permissive to SARS-CoV-2 infection. Thus, KIM-1 is an alternative receptor to ACE2 for SARS-CoV-2. KIM-1 targeted therapeutics may prevent and/or treat COVID-19.